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SCLEROTHERAPY TREATMENT INSIGHTS David Green, MD
Injection sclerotherapy is the procedure in which a sterile solution is deposited into the intraluminal space of an ectatic vein to effect its permanent eradication. This requires the production of full mural denaturation for the entire length of the unwanted vein.’ Incomplete mural denaturation is associated with persistence of the vein; destruction beyond the confines of the vein wall may result in extravascular tissue necrosis (Fig. , ) . I 3 Achieving the appropriate extent of mural denaturation, while minimizing the incidence of adverse effects, minimizing patient discomfort, and treating the maximal number of veins during each session, are goals of sclerotherapy. Accomplishing these goals requires more than skill at cannulation and injection into a vein. In addition, the physician should have a thorough understanding of the mechanism of action of sclerotherapy and knowledge of lower extremity venous anatomy and hemodynamics-within competent veins as well as in the presence of venous insufficiency. Insuring a satisfactory outcome, from the patient’s perspective, also requires realistic expectations and an awareness of, and willingness to accept, the possibility of adverse effects associated with treatment. Therefore, the patient should be thoroughly informed about the procedure and its possible risks. After a brief review of the venous anatomy
of the lower extremity and the most common vascular ectasias for which patients present for treatment, this article provides some of the author’s treatment techniques and guidelines for injection sclerotherapy of venous telangiectases and varicose veins. The salient aspects of the author’s pretreatment consultation, posttreatment recommendations, and documentation suggestions are also provided.
VENOUS SYSTEM ANATOMY OF THE LOWER EXTREMITY The veins of the lower extremity can be divided into 3 components: the superficial venous system; deep venous system; and perforating veins.7
Superficial Venous System The superficial venous system includes veins that are superficial to the deep fascia. These veins, for the most part, reside in the cutaneous and subcutaneous tissue. Any visible vein of the lower extremity, whether normal or abnormally dilated, will be part of this system.
Private Practice, Bethesda, Maryland
DERMATOLOGIC CLINICS ~
VOLUME 16 * NUMBER 1 *JANUARY 1998
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Figure 1. The fate of a vein after injection sclerotherapy. A, Incomplete mural denaturation and the damaged segments of vein reconstitute and the lumen recanalizes. B, Full mural denaturation results in the complete and permanent eradication of the vein. C and 0, The course after there has been not only full mural denaturation, but extravascular destruction of tissue. C,Although the vein disappears there will be damage to the surrounding dermis. 0, If this dermal destruction extends to the overlying epidermis, an ulcer will develop that is likely to result in textural change. Figure 2. Dilated blue-green veins demonstrate incompetent reticular varicose veins. They reside in the subcutaneous fat and are clinically dilated and hemodynarnically incompetent. Figure 3. Tortuous, protruding veins demonstrate varicose veins. They reside within or deep to the subcutaneous fat and are clinically dilated and hernodynamically incompetent. Figure 4. These photographs juxtapose a 33 gauge needle next to capillaty telangiectases (A) and venous telangiectases (B). It is apparent that capillary telangiectases are more narrow than the cannula of even a 33 gauge needle, making it impossible to properly cannulate the vessel.
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A
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D Figure 1.
Figure 2.
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Figure 3.
6 Figure 4.
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Figure 5.
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Figure 8.
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B Figure 11.
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B Figure 12.
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Figure 5. Retrograde venous blood flow into the hub of the needle indicating proper intraluminal cannulation of the vein. Figure 8. Before and after sclerotherapy. Figure 10. Before and after sclerotherapy. Figure 11. Before and after sclerotherapy. Figure 12. Before and after sclerotherapy.
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Deep Venous System This system includes all veins that are located within and around muscles and are surrounded by the deep fascia. These veins are the primary course through which at least 90% of the venous blood from the lower extremity is transported pr0ximal1y.l~
Perforating Veins This component includes veins that course transversely in the lower extremity (the veins of the superficial and deep venous system are primarily axially oriented). They directly connect the above two venous systems and normally transport blood from the superficial to the deep veins.
VENOUS SYSTEM HEMODYNAMICS OF THE LOWER EXTREMITY All competent veins have valves to insure the centripetal flow of blood. The known exceptions in the lower extremity include veins less than 1 mm in diameter; the perforating veins of the foot; and so-called oscillating reticular veins.l8 These oscillating reticular veins are valveless veins that link adjacent valved venous tributaries and are surmised to allow equilibration of blood flow and pressure in the tissue and may also play a role in thermoregulation. They have been identified especially on the thigh but may be a ybiquitous component of the cutaneous vasculature. Under normal circumstances axially oriented veins transport blood proximally, and transversely oriented veins transport blood from the superficial to the deep venous system. When veins become incompetent their normal unidirectional, centripetal flow of blood is disturbed and they then permit blood to flow in a retrograde direction, depending upon the gravitational force to which intraluminal blood is subjected. This retrograde flow produces elevated intravascular pressure that progressively promotes vein distension, dilatation, and tortuosity. If elevated venous pressure is transmitted more proximally in the vascular circuit (i.e., in a retrograde direction) it may result in elevated intracapillary hydrostatic pressure. When elevated intracapillary hydrostatic pressure is transmitted to the surrounding tissue it may result in what is referred to as the cutaneous changes of venous insufficiency.
TYPES OF VASCULAR ECTASIAS OF THE LOWER EXTREMITY All visibly and palpably dilated veins of the lower extremity are part of the superficial venous system. That is, these are veins superficial to the deep fascia, and are usually located in the dermis or subcutaneous fat. Most superficial venous insufficiency (i.e., varicose veins or venous telangiectases) is present without clinically apparent deep venous insufficiency. Even if veins of the deep venous system should become dilated and incompetent they do not become clinically apparent, visually or by palpation. However, their incompetence may be manifest by the resulting cutaneous changes of venous insufficiency (i.e., venous stasis dermatitis, venous ulceration, dermatoliposclerosis). There are arbitrarily 3 types of clinically ectatic, functioning incompetent blood vessels of the lower extremity for which patients seek treatment. These include varicose veins, telangiectatic veins, and telangietatic capillaries. Knowledge of the differences between these dilated blood vessels is necessary in order to appropriately and effectively treat them.
Varicose Veins This group includes the largest diversity of ectatic veins based upon their size and depth below the surface. These are ectatic veins that are greater than 2 millimeters in diameter and may exceed 2 centimeters in diameter. They may protrude above the plane of the skin and often follow a tortuous course. Those that reside in the deep dermis and subcutaneous fat often appear blue-green in color and they represent varicosities of reticular veins (Fig. 2).17When varicosities reside in the subcutaneous fat or deeper, the overlying skin may be too thick for any intraluminal blood to be visualized and, having no apparent color, they may merely protrude above the skin plane. They may represent varicosities of the saphenous veins or their larger tributaries (Fig. 3). Many physicians and patients alike incorrectly refer to large, nodular varicosities as being deep varicose veins when in fact they are constituents of the superficial, not deep, venous system.
Telangiectatic Veins These are ectatic veins that are up to 2 millimeters in diameter. They usually appear
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reddish-blue or blue in color and they reside in the dermis. Many people commonly refer to them as spider veins. Telangiectatic Capillaries These are ectatic capillaries that are usually less than 0.2 millimeter in diameter. They appear red or pink in color and reside in the papillary dermis. Many people commonly refer to them as broken blood vessels. It is important to be able to distinguish capillary telangiectases from venous telangiectases. While varicose veins and venous telangiectases respond to sclerotherapy, capillary telangiectases usually do not. Not only are capillary telangiectases relatively unresponsive to sclerotherapy, but the development of telangiectatic capillary matting is commonly observed as an adverse effect when one attempts to treat them by sclerotherapy. With experience it becomes quite easy to distinguish capillary from venous telangiectases (Fig. 4). Since capillary telangiectases are usually less than 0.2 millimeter in diameter, they are more narrow than the cannula of a #33 gauge needle (which has an outer diameter of 0.2 millimeter). However, as a general rule, any telangiectasia with a diameter more narrow than a #30 gauge needle (which has an outer diameter of 0.3 millimeter) is probably a capillary telangiectasia-not a venous telangiectasia-and treatment should proceed with caution since they are unlikely to respond and their treatment is associated with a greater incidence of adverse effects. The treatment of telangiectatic capillaries can be attempted by photothermal coagulation with a vascular laser, i.e., a laser in which hemoglobin is the chromophore. Needles can be used to estimate the diameter of ectatic vessels. The cannula of a needle is described in terms of its gauge. The corresponding outer diameter, in millimeters, is given in the following chart: gauge: 33 30 27 25 21 18 width (mm): 0.20 0.30 0.41 0.51 0.90 1.27 INITIAL CONSULTATION An initial consultation is scheduled prior to any treatment visits. The purpose of this consultation is to determine the nature of a patient’s venous disease (i.e., superficial venous system insufficiency, deep venous system insufficiency, or both); the type of ectatic
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superficial vessels present (i.e., varicose veins, venous telangiectases, or capillary telangiectases); the extent of the problem (i.e., few or numerous; localized or widespread; discrete or grouped); and whether the patient is an acceptable candidate for treatment. It is also an opportunity to understand the patient’s expectations from treatment, inform her of results that can realistically be achieved from treatment, and insure that she has an understanding of, and willingness to accept, the possibility of adverse effects. The following exchange of information transpires during this pretreatment consultation. History The patient is queried regarding the age of onset of her ectatic veins; whether there were any associated events around the time of their development, i.e., pregnancy or trauma; the presence of any symptoms that she attributes to these veins; family history of venous disease; history of deep venous thrombophlebitis; and any other relevant information. The development of hyperpigmentation after even mild trauma is of interest as is the tendency towards bruising. Patients who bruise easily tend to be somewhat more inclined to linear postsclerotherapy hyperpigmentation (see Minimizing Complications: Hyperpigmentation later in text). The author always inquires as to which ectatic veins the patient wants removed. Often patients are only interested in removing ectatic veins at a particular site, i.e., below the knees, or of a particular size, i.e., only varicose veins and not venous telangiectases. It is important to know which ectatic veins the patient wants removed so that an estimate of the total number of treatment sessions can be provided at the conclusion of the consultation. Clinical Examination The lower extremities are examined to determine the extent of venous disease and the type of ectatic blood vessels that are present (see Types of Vascular Ectasias of the Lower Extremity earlier in text). The skin is examined to determine not only the presence of any cutaneous changes of chronic venous insufficiency but also any other skin lesionswhether or not they may be secondary to venous disease.
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All skin changes and lesions are noted including, for example, the presence of actinic damage, melanocytic nevi, lentigines, dermatofibromas, and pigmentary alteration. After treatment has been initiated, most patients have a heightened awareness of their treated veins and the adjacent skin. Many have a tendency to attribute pre-existing lesions (which they never previously noticed) to sclerotherapy . Varicose veins are palpated and balloted to clinically determine if they are being subjected to significantly elevated venous pressure. Significantly elevated venous pressure in varicose veins is an indication of reflux from the deep venous system. Noninvasive Vascular Testing
A thorough discussion of noninvasive vascular testing is beyond the scope of this article. However, this diagnostic testing can be valuable in the evaluation of the extent of venous insufficiency, and in determining if surgical intervention will be beneficial, i.e., in the presence of venous reflux from the deep into the superficial venous system. Noninvasive vascular testing is indicated to confirm a clinical suspicion of deep venous system incompetence and in determining the presence and location of venous reflux from the deep venous system into the superficial venous system (i.e., at a saphenofemoral or saphenopopliteal junction or through perforating veins). Routine duplex ultrasound scanning and plethysmographic testing of patients with uncomplicated venous telangiectases and varicose veins, i.e., without any clinical evidence of deep venous insufficiency nor of any clinically significant reflux from the deep venous system into the superficial venous system, are unnecessary. Explanation of the Procedure
All aspects of sclerotherapy are thoroughly explained including a brief discussion of the mechanism of action of sclerotherapy. It is emphasized that sclerotherapy irreversibly alters the vein by dissolving the mural layers. This is followed by the resorption of the unwanted veins-they are not merely being collapsed or plugged by the solution. The patient is informed of the postsclerotherapy course
and the requirement for compression, after the treatment of either varicose veins or prominent venous telangiectases. It is made clear to the patient that it can take several weeks to several months for the body to resorb treated veins. If she expects her veins to be gone after just a few days or weeks, she may be quite disappointed with the treatment. Potential adverse effects such as postsclerotherapy hyperpigmentation and telangiectatic capillary matting are discussed and photographs are shown. Although less common, the patient is informed of the possibility of cutaneous necrosis and subsequent scarring. Patients who are pregnant or breast feeding are never treated even though no teratogenic nor mutagenic effects of sclerosing agents have ever been demonstrated.
Discussion of Treatment Plan
The estimated number of treatment sessions is outlined as is the interval between them. If a patient is concerned about the development of postsclerotherapy hyperpigmentation she may wish to wait 1 month-to observe if this develops-before pursuing additional treatment. However, if this is not a concern, in this author’s experience a safe interval between treatment sessions is 48 hours if the maximal recommended dose of a sclerosing agent is administered during each treatment. The pharmacokinetics of the two FDA approved sclerosing agents is unknown (ESI-Lederle, Inc., Philadelphia, PA, 1997 and Glenwood-Palisades, Tenafly, NJ, 1997, personal communication). In those instances when postsclerotherapy compression is required, i.e., for varicose veins and prominent venous telangiectases, the patient is informed of the duration that gradient compression hose is recommended. This may range from several days to 2 months, and rarely longer. Written postsclerotherapy instructions and a sclerotherapy consent form are reviewed with the patient and copies are given for her to review at home. This consent form includes information on the nature of the procedure and possible adverse effects. If she decides to undergo treatment, she is requested to bring the signed consent form with her to the office at the time of her first treatment session.
SCLEROTHERAPY TREATMENT INSIGHTS
DOCUMENTATION Chart Notes All pertinent positive and negative history and clinical findings should be included. These notes should document the appearance, distribution, and extent of ectatic veins. For larger varicose veins this author always includes a subjective estimate of the degree of elevated intravascular pressure, i.e., mild, moderate, or firm, as is discerned on palpation and ballottement of the veins. Also noted is the presence of pre-existing capillary telangiectases, alteration in pigmentation, and any nearby cutaneous lesions (as noted in Initial Consultation: Clinical examination earlier in text). These changes are shown to the patient prior Zo treatment and this is noted as well. The records should indicate that the procedure and the possible adverse effects were thoroughly explained to the patient. If the patient seems to be at increased risk of developing adverse effects, she should be told of this in advance and this should be included in the notes.
Photodocumentation Pretreatment photographs are invaluable and should be taken of every treatment site. We all have very short memories and most patients rarely remember the pretreatment appearance of their veins. Pre-existing skin lesions, which were never noticed by the patient, are often first observed after, and incorrectly attributed to, treatment.
Informed Consent A signed copy of the informed consent form that had been reviewed with the patient at the time of the initial consultation, and which she has had an opportunity to review at home, should be part of the records.
PRETREATMENT PREPARATION After the initial consultation, the patient may schedule an appointment for a treatment session. The patient should not have applied any cream, lotion, or bath oil to her lower extremities after her last bath or shower. These products make piercing the skin diffi-
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cult when attempting to cannulate the vein. In addition, no coverup makeup should be applied over any veins that the patient wants treated. Makeup makes it difficult to visualize the veins and estimate their depth. There is no need to discontinue any drug with anticoagulant or antithrombotic activity. These agents do not increase vessel fragility and should not affect treatment technique nor the concentration of the sclerosant to be injected.” There will only be increased ecchymoses if blood inadvertently extravasates from the vein during treatment.
INITIAL TREATMENT VISIT If she has not already done so, the patient is asked to sign the sclerotherapy consent form. Pretreatment photographs are taken. If gradient compression hosiery will be required, the patient is measured. An inventory of these stockings is maintained in the office so that they can be applied immediately after treatment. If more than one treatment session will be required, this author usually begins with the most prominent and unsightly of veins that the patient wants removed. As a general rule, larger veins are treated initially and smaller veins are treated during subsequent sessions in decreasing order of size. At the end of the treatment session the postsclerotherapy instructions are reviewed.
SCLEROTHERAPY TECHNIQUE Sclerotherapy is an exquisitely techniquesensitive procedure. If veins do not respond to treatment, it is usually a result of inadequate technique and not any inherent limitation of the procedure. Treatment of varicose veins is similar to that of venous telangiectases. However, the application of external compression is usually vital after the injection of varicose veins while it is often unnecessary after treating venous telangiectases. (See Sclerotherapy Technique: Postsclerotherapy compression, later in text).
lntravascular Injection It is mandatory that the sclerosant is injected intravascularly. Extravascular injection can produce necrosis with almost every
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available sclerosant (hydroxypolyethoxydodecane is the e~ception).~ Even if necrosis is unlikely to develop, there is an increased incidence of adverse effects, i.e., hyperpigmentation and telangiectatic capillary matting, after extravascular deposition of a sclerosant. The intravascular deposition of sclerosant requires the intravascular localization of the needle cannula and needle tip. This is confirmed by observing passive retrograde flow of blood into the needle hub or syringe barrel (Fig. 5). Once this is established, injection can proceed. Volume of lnjectate
The volume of sclerosant to inject into a vein depends upon the vein's volume. If there are numerous tributaries, injection can continue until all of the veins have been exposed to the solution. For large varicose veins, often the maximum quantity of sclerosant that can be safely administered during any one treatment session is given into one puncture site. Additional varicosities can be treated during subsequent sessions. More important than the volume or rate of injection is the duration of direct contact the sclerosant has with the luminal surface of the vein. Concentration of lnjectate
The concentration of the injected sclerosant should depend upon the mural thickness of the vein. Mural thickness is directly correlated with the lumen diameter. That is, the wider the diameter of the vein the greater is its wall thickness and the higher should be the concentration of the injected sclerosant. The appropriate concentration of sclerosant will also depend upon whether the sclerosant is being diluted by any intravascular blood (see Sclerotherapy Technique: Empty vein technique, later in text). Even if the sclerosant is too dilute to effect full mural destruction it may nonetheless produce enough mural disruption to be thrombogenic. However, ultimately the vein walls will be reconstituted, the lumen will be recanalized, and the vein will reappear. Cannulation of the Vein
Cannulation of a vein should always be brisk to insure minimal trauma to the vein.
This minimizes the chance of extravasation of both sclerosant and blood. Prior to inserting the needle into the skin, the cannula should be bent at the hub so that the syringe can be comfortably held while the cannula remains parallel to the skin (Fig. 6). The bevel of the needle should always be up and not to the side. If the vein cannot be cannulated, or if the needle tip is no longer intravascular, injection should not proceed or cease, respectively. If a telangiectatic vessel is too small to be cannulated by a #30 gauge needle, it is likely a telangiectatic capillary and not a telangiectatic vein. In this author's experience, telangiectatic capillaries respond poorly to sclerotherapy and their injection is associated with a high incidence of telangiectatic capillary matting and necrosis, compared to the treatment of venous telangiectases. Empty Vein Technique
When treating varicose veins, the empty vein technique should be employed.'j,l5 That is, the leg should be elevated to at least a horizontal level to minimize the volume of blood within the intraluminal space. Blood only dilutes the sclerosant, rendering it less potent. If the sclerosant is diluted, it may not produce sufficient mural destruction to result in vein resorption and the vein will persist. In addition to employing this empty vein technique, postsclerotherapy compression is important to minimize the volume of any thrombus that develops within the intraluminal space after treatment. Even if full mural destruction is achieved, without significant compression, blood will seep into the intraluminal space, become coagulated, and prolong the time for the complete resorption of the vein. Postsclerotherapy Compression
Immediate application of external compression after injection is important to minimize the return of blood into the treated vein. This minimizes the volume of the formed thrombus. Thrombosis not only prolongs resorption time, but predisposes to symptomatic superficial thrombophlebitis. In this author's experience, ectatic veins less than two millimeters in diameter usually do not benefit from postsclerotherapy compression. That is, gradient
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Figure 6. A depicts how the cannula of the needle should be bent so that it remains parallel to the plane of the skin and veins during injection. 6, If the cannula is not bent, it is difficult to impossible to maintain plane of the skin and veins, while trying to comfortably hold the syringe.
compression hosiery does not diminish the volume of interluminal thrombus that develops after treatment of these smaller veins. However, it is indicated for those treated veins greater than 3 millimeters in diameter, and significantly reduces the volume of the intraluminal thrombus that develops after treatment of larger veins. For those veins that are 2 to 3 millimeters in diameter, the need for compression is determined on an individual basis. Compression is most effectively achieved with gradient compression hosiery and is well tolerated by almost all patients. Most patients will achieve adequate compression with Class 2 (30 mmHg to 40 mmHg) hosiery. For very high pressure varicosities Class 3 (40 mmHg to 50 mmHg) hosiery may be required. The location of the varicosities will determine whether the hosiery must extend as high as the knee, mid-thigh, full-thigh or be pantyhose. The pressure that describes gradient compression hosiery (in millimeters of mercury) is the pressure exerted at the level of the ankle. The pressure exerted at the level of the calf would be 70%, along the mid thigh 50%, and along the upper thigh only 40% of that at the ankle. For example, a stocking with a
pressure of 30 mmHg to 40 mmHg will exert a pressure of 21 mmHg to 28 mmHg at the calf (70%), 15 mmHg to 20 mmHg at the mid thigh (50%) and 12 mmHg to 16 mmHg at the upper thigh (Fig. 7). If compression hosiery is recommended, the patient must be cautioned that foot discomfort (i.e., pain, cramping, numbness) may be experienced, especially with leg elevation. When it occurs, it is usually at bedtime and the patient may be awakened from sleep. These symptoms are readily ameliorated when the leg is dependent, as with standing and walking. This pain represents tissue hypoxia, i.e., iatrogenic claudication. It results from external compression and diminished arterial flow at the ankle. While standing, this reduction in arterial pressure to the foot is insignificant. However, in the elevated position, when the arterial pressure at the ankle is no longer augmented by the gravitational hydrostatic force exerted on this long column of blood, this reduction in arterial blood pressure can become significant. If pain is experienced when the patient stands, either the stocking is too tight or the patient’s arterial supply is diminished, i.e., arteriosclerosis is present, and external compression should not be applied.
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maximum 40%
maximum 50%
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ized examination table will be comfortable for the patient and will also make it easy to move the patient so that all veins will be easily accessible without the need for the physician to contort while injecting. A stool with wheels will make it easier for the physician to be seated and comfortably positioned while treating the patient. Adequate overhead lighting is invaluable for visualizing veins. It is much easier to visualize veins under fluorescent lighting compared to incandescent lighting. Specifically, cool white fluorescent light (rated at 4100" Kelvin or cooler) highlights the blue-green color of veins.
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Syringes Figure 7. The progressive proximal decrease in exerted pressure with gradient compression stockings. At point d, just below the knee, the external pressure is 70% of that at the ankle; at point f, along the mid thigh, it is 50% of that at the ankle; at point g, along the upper thigh, it is 40% of that at the ankle. (Courtesy of MediUSA, Arlington Heights, IL.)
Contrary to some recommendations, the application of gauze pads or cotton taped to the overlying skin provides no significant external compression. Although elastic bandages can be applied, they have disadvantages compared to gradient compression hosiery: Elastic bandages loosen considerably and the adequacy of compression is unpredictable; once removed by the patient, i.e., to bathe, they are not usually reapplied as tightly by the patient; if the patient does keep the elastic bandage wrapped tightly enough, it may act like a tourniquet, and distal swelling (especially of the foot and ankle) should be expected. SUPPLIES
Injection sclerotherapy requires few supplies and rarely any high technology instrumentation. However, carefully selecting those supplies and equipment will make treatment less tedious and laborious and may enhance treatment techniques. Treatment Environment
A well-lit treatment environment is most conducive to a successful outcome. A motor-
Three-milliliter syringes are most practical. They hold an adequate volume of solution to treat many small veins or a larger varicose vein. They fit comfortably in a hand compared to smaller and larger volume syringes. Fine control of the plunger is usually easier than with a 1 milliliter syringe. Choosing the best syringe will require testing of several different brands. A syringe in which there is consistent and acceptable plunger resistance through the entire length of the barrel is the syringe that should be used. Most syringes have rubber or latex stoppers at the end of the plunger. Some sclerosants or their preservatives can dissolve latex and the physician can feel an increase in the resistance of the plunger as it travels through barrel. This is most commonly observed with those solutions of polidocanol (hydroxypolyethoxydodecane) that contain chlorobutanol (trichloroisobutyl alcohol) as a preservative. If this occurs, it will be necessary to discard the syringe after each 3 milliliters is injected or to use glass syringes. This author does not find glass syringes helpful since the plunger resistance is usually not as constant and consistent as it courses through the barrel, compared to plastic syringes. Needles
These serve as a conduit for the sclerosing solution. They should be sharp to minimize pain, penetrate tissue easily, and minimize trauma to the vein. Unfortunately, needles dull easily. If a dull needle is used to cannulate a vein, it may tear rather than pierce the
SCLEROTHERAPY TREATMENT INSIGHTS
vein wall. This can lead to leakage of sclerosant or blood into the surrounding tissue. For optimal vein penetration, a needle should be discarded after 1 to 2 injections. There is a great disparity in the quality of different brands of needles. The finest needles have very sharp tips with no burrs. Needles with burrs on their tips d o not permit a smooth entrance into the skin and vein. It will be necessary to experiment with different brands of needles to determine which manufacturer consistently produces the highest quality needle. This author has found that the most expensive needles are not necessarily of the highest quality. The vast majority of veins that will be injected-no matter how large or small-can be treated with needles that are either 27 gauge or 30 gauge X 1/2 inch.
Magnification Cannulation and injection of a vein require careful visualization. Magnification greatly aids in the process of vein cannulation and confirmation of the intraluminal localization of the needle tip. This author usually uses 3.0 diopters of magnification, or greater, which provides a working distance of 30 centimeters to 40 centimeters.
Sclerosant The sclerosant of choice is usually the one with which the physician has the greatest experience. However, if this author was to choose only one sclerosant to use it would be polidocanol (hydroxypolyethoxydodecane). This is a nonionic surfactant that is commercially available in several concentrations including 0.5'10, LO%, 2.0%, 3.0°/o, and 5.0%. Polidocanol may be diluted to any concentration that the physician feels is appropriate using a sterile solution of 0.9% sodium chloride. It can be used to treat any ectatic vein encountered on the lower extremity-from the smallest venous telangiectasia to the largest varicose vein. The 5.0% solution is quite potent and will easily be able to destroy the full mural thickness of even the largest varicosity. When diluted to as low as 0.1%, it can be used to treat the smallest and most fragile of venous telangiectases. It is painless to inject.* And, unlike all other sclerosants, polidocanol will not produce ulceration or necrosis if ex-
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travascular tissue is exposed to this agent. However, like every other sclerosant, it may be associated with extravascular necrosis and ulceration in spite of appropriate intravascular injection. The underlying cause of ulceration after intravascular injection is still not established but there are several possible explanations (see Minimizing Complications: Cutaneous necrosis later in the text). Polidocanol is not an FDA approved sclerosant. Another commonly used sclerosant is sodium tetradecyl sulfate, which is an anionic surfactant. At an equal concentration it is somewhat more potent than polidocanol. Sodium morrhuate, also an anionic surfactant, has been used for more than 60 years. It is quite a potent sclerosant and is recommended for treating only varicose veins, but not recommended for treating venous telangiectases. Sodium tetradecyl sulfate and sodium morrhuate are the only FDA approved sclerosants for treating vascular ectasias of the lower extremity. Hyperosmotic sclerosants, such as hyperosmotic sodium chloride, have been used for many decades. It is commercially available as a 23.4% solution (4 milliequivalents/milliliter). Although not FDA approved as a sclerosant, it is an FDA approved abortifacient. Hyperosmotic solutions have several disadvantages: they are weaker than the surfactant sclerosants and therefore are less effective for larger, thicker-walled, veins; they are usually quite painful to the patient during intravascular infusion; they are likely to produce necrosis in extravascular tissue; their range of effective concentrations is much more limited compared to the surfactant sclerosants, i.e., hyperosmotic sodium chloride is useful over a less than 3-fold range in concentration (from 12% to 30%) compared to a 50-fold range for sodium tetradecyl sulfate or polidocanol (0.1% to 5.0%).
POSTSCLEROTHERAPY ACTIVITY Immediately after treatment, patients may resume all normal activities including walking and standing. In those patients treated for venous telangiectases this includes even strenuous activity, (i.e., jogging, aerobic exercise, and swimming) may resume. It has been this author's experience that the level of the patient's activity after treatment does not affect the volume of postsclerotherapy intravas-
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cular thrombosis within the treated venous telangiectases. After treating larger channel varicosities, i.e., greater than 3 millimeters in diameter, this author has found that limiting strenuous activity, i.e., jogging and aerobic exercise, for the first 24 to 48 hours (depending upon the size of the varicosities and their intraluminal pressure) limits the degree of postsclerotherapy intravascular thromboses within the treated varicose vein. After this initial 24 to 48 hour period as long as the gradient compression hosiery is worn, the patient may resume all activities. It has been recommended in the past that patients walk an arbitrary distance, i.e., 3 miles, immediately after treatment and daily for some time thereafter.12 Many physicians continue to promote this posttreatment regimen. The rationale for this recommendation is that walking reduces the volume and pressure of blood in the treated vein and stimulates fibrosis. In addition, it has been thought that immediate ambulation following injection prevents any intimal damage within deep veins from becoming a site for propagation of thromb~sis.'~ There has never been any scientific evidence nor any controlled studies to justify this recommendation. This author has not found any differences in the rates of vein resorption whether or not the patient walks for an arbitrary time or distance each day. Neither has this author ever seen a patient who has developed any clinical indications of deep vein thrombosis in the absence of any specific postinjection regimen of ambulation or activity.
MINIMIZING COMPLICATIONS Employing scrupulous injection techniques will insure minimal risk of adverse effects. However, even the most dexterous and meticulous sclerotherapist will have patients who sustain adverse effects. Commonly occurring adverse effects include the development of hyperpigmentation, telangiectatic capillary matting, and superficial cutaneous necrosis resulting in scar formation. Complications can be expected when less than optimal techniques are employed. For example, complications are common if there is inadvertent extravascular injection or if too concentrated a solution is injected than is required for the vein being treated. Both circumstances may be associated with develop-
ment of excessive inflammation or necrosis at the treatment site or along the course of the treated vein. In general, complications can be minimized by injecting: the lowest appropriate concentration of solution; the lowest appropriate volume of solution; at the slowest rate; and at the lowest pressure. In those patients predisposed to the 2 most commonly occurring adverse effects, i.e., hyperpigmentation and telangiectatic capillary matting, following these guidelines will minimize but not prevent them from developing. Patients who are predisposed to these adverse effects should be forewarned that if such side effects are sustained after one treatment, they are likely to occur after each subsequent treatment.
Hyperpigmentation An incidence of postsclerotherapy hyperpigmentation of 30% is not uncommon, even with the most scrupulous of techniq~es.'~ It appears as linear tan to brown pigmentation along the course of the treated vein and is the result of hemosiderin deposition? Sometimes melanin contributes to this pigmentation due to its incontinence from the overlying epidermis resulting from underlining dermal inflammation surrounding the treated vein. Minimizing the amount of blood in the treated vein, i.e., the empty vein technique, and minimizing venous return after injection will help reduce the incidence of this problem. For larger veins, this requires postsclerotherapy compression for an adequate period of time. For venous telangiectases, postsclerotherapy compression is not as effective in reducing the incidence of this problem as it is for larger veins. Hyperpigmented patches at injection sites are usually due to extravasation of blood. Such extravasation commonly occurs with poor technique and is usually preventable. Fortunately, hyperpigmentation resolves in almost all patients but can take months and sometimes years before it completely disappears.
Telangiectatic Capillary Matting An incidence of telangiectatic capillary matting of 16% to more than 50% has been reported even when the procedure is carefully and properly performed.', In those pre-
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disposed, it is impossible to prevent this problem. It seems to be more common in those who are fair complected, especially those who have telangiectatic matting, or at least capillary telangiectases, in the vicinity of the treatment site. It will commonly develop if excessive inflammation develops at the treatment site. Although some authors have not found this adverse effect to occur in men; this author has observed telangiectatic capillary matting as an adverse effect in men as well as in women. Such excessive inflammation frequently develops if too concentrated of a sclerosant is injected for the caliber of the telangiectatic veins being treated. If a patient seems predisposed to this problem it is wise to inject a solution that is somewhat more dilute than would otherwise be injected into similar caliber veins in a nonpredisposed person. Certain locations, such as the distal medial thigh, seem especially prone to this adverse effect. Unlike hyperpigmentation, which eventually completely resolves in almost all patients, telangiectatic capillary matting may persist.'O It is difficult to know the incidence of capillary telangiectatic matting and the rate at which it spontaneously involutes since the frequency with which this is observed is dependent upon the vigilance of the observer.
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If telangiectatic matting does persist, treatment can be attempted through photothermal coagulation using a laser that treats vascular ectasias.
Cutaneous Necrosis There are several mechanisms that can account for the development of this adverse effect. It may be seen not only with inadvertent extravascular injection but after correct intravascular injection. If a sclerosant (other than polidocanol) seeps into the extravascular tissue, necrosis may occur. The likelihood of necrosis will depend upon the particular sclerosant injected and the volume and concentration that extravasates. Meticulous technique should minimize the incidence of extravasation. However, necrosis seems to occur even more commonly in the absence of extravasation of sclerosant, i.e., after proper intravuscuZar injection. Intense blanching of the surrounding skin or at a distant site during injection is a warning that this problem is likely to develop. The pathophysiology of this complication is not certain but is most likely from either intense vasoconstriction or retro-
Figure 9. Before and after sclerotherapy.
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Figure 13. Before and after sclerotherapy.
grade flow of sclerosant, which damages the more proximal end arterioles. Either mechanism will cause tissue hypoxia and subsequent necrosis. Any sclerosant can be implicated, including polidocanol. If blanching is noted at the time of treatment, injection should immediately cease and the involved skin gently massaged. Some have claimed that the application of a cutaneous vasodilator, such as nitroglycerin ointment, reduces the development or extent of subsequent necrosis.1° Well controlled studies have never been performed so it is unclear if this can really reduce the incidence or extent of ulceration. However, it is worthwhile applying this ointment if cutaneous blanching appears and is sustained, i.e., persists even though injection has ceased. If devitalization of tissue seems likely, or has developed, the area should be treated with a wound dressing material or the application of an occlusive ointment to prevent desiccation of tissue and promote wound healing by secondary intention. These ulcers often take two months or longer before they have re-epithelialized. There is usually alteration in skin texture, i.e., scarring. Patients require reassurance regarding the eventual healing of these sites and should be told at the onset that healing will be prolonged so that they do not lose confidence in
the appropriateness of the care the physician is recommending. Sclerotherapy remains a safe and effective procedure to permanently eradicate ectatic veins as is demonstrated in the clinical examples in Figures 8 to 13. References 1. Davis LT, Duffy DM: Determination of incidence and risk factors for postsclerotherapy telangiectatic matting of the lower extremity: A retrospective analysis. J Dermatol Surg Oncol 16:327-330, 1990 2. Duffy D M Small vessel sclerotherapy: An overview. Adv Dermatol3221-242, 1988 3. Duffy DM: Understanding sclerotherapy. In Lask GP, Moy RL (eds): Principles and Techniques of Cutaneous Surgery. New York, McGraw-Hill, 1996, pp 403417 4. Fegan G: Varicose Veins: Compression Sclerotherapy. Hereford, Berrington Press, 1990, p vii 5. Fegan G: Varicose Veins: Compression Sclerotherapy. Hereford, Berrington Press, 1990, p 89 6 . Fegan WG: Continuous compression technique of injecting veins. Lancet ii:109-112, 1963 . 7. Goldman MP: Sclerotherapy: Treatment of Varicose and Telangiectatic Leg Veins. St. Louis, MosbyYearBook, 1991, p 61 8. Goldman MP, Bennett RG: Treatment of telangiectasias: A review. J Am Acad Dermatol17167-182,1987 9. Goldman MP, Kaplan RP, Duffy DM: Post-sclerotherapy hyperpigmentation: A histologic evaluation. J Dermatol Surg Oncol 13:547-550, 1987
SCLEROTHERAPY TREATMENT INSIGHTS 10. Goldman MP, Sadick NS, Weiss RA: Cutaneous necrosis, telangiectatic matting, and hyperpigmentation following sclerotherapy: Etiology, prevention and treatment. Dermatol Surg 21:19-29, 1995 11. Green D Compression sclerotherapy techniques. Dermatol Clin 7137-146, 1989 12. Green D: Mechanism of action of sclerotherapy. Semin Dermatol 12:8%97, 1993 13. Green D: Sclerotherapy for the peramanent eradication of varicose veins: Theorectical and practical considerations. J Am Acad Dermatol (to be published) 14. Kosinski C: Observations on the superficial venous system of the lower extremity. J Anat 60131-142, 1926
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15. Linser K: Die behandlung der krampfadem mit intravarikosen kochsalzinjektionen (The treatment of varicose veins with intravenous injections of tabIe salt). Dermatologische Wochenschrift 81:1345-1351, 1925 16. Norris MJ, Carlin MC, Ratz JL: Treatment of essential telangiectasia: Effects of increasing concentrations of polidocanol. J Am Acad Dermatol 20:643-649, 1989 17. Somjen GM: Anatomy of the superficial venous system. Dermatol Surg 21:3545, 1995 18. Taylor GI, Caddy CM, Watterson PA, et al: The venous territories (venosomes) of the human body: Experimental study and clinical implications. Plast Reconstr Surg 86:185-213, 1990
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SCLEROTHERAPY TREATMENT INSIGHTS David Green, MD
Injection sclerotherapy is the procedure in which a sterile solution is deposited into the intraluminal space of an ectatic vein to effect its permanent eradication. This requires the production of full mural denaturation for the entire length of the unwanted vein.’ Incomplete mural denaturation is associated with persistence of the vein; destruction beyond the confines of the vein wall may result in extravascular tissue necrosis (Fig. , ) . I 3 Achieving the appropriate extent of mural denaturation, while minimizing the incidence of adverse effects, minimizing patient discomfort, and treating the maximal number of veins during each session, are goals of sclerotherapy. Accomplishing these goals requires more than skill at cannulation and injection into a vein. In addition, the physician should have a thorough understanding of the mechanism of action of sclerotherapy and knowledge of lower extremity venous anatomy and hemodynamics-within competent veins as well as in the presence of venous insufficiency. Insuring a satisfactory outcome, from the patient’s perspective, also requires realistic expectations and an awareness of, and willingness to accept, the possibility of adverse effects associated with treatment. Therefore, the patient should be thoroughly informed about the procedure and its possible risks. After a brief review of the venous anatomy
of the lower extremity and the most common vascular ectasias for which patients present for treatment, this article provides some of the author’s treatment techniques and guidelines for injection sclerotherapy of venous telangiectases and varicose veins. The salient aspects of the author’s pretreatment consultation, posttreatment recommendations, and documentation suggestions are also provided.
VENOUS SYSTEM ANATOMY OF THE LOWER EXTREMITY The veins of the lower extremity can be divided into 3 components: the superficial venous system; deep venous system; and perforating veins.7
Superficial Venous System The superficial venous system includes veins that are superficial to the deep fascia. These veins, for the most part, reside in the cutaneous and subcutaneous tissue. Any visible vein of the lower extremity, whether normal or abnormally dilated, will be part of this system.
Private Practice, Bethesda, Maryland
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Figure 1. The fate of a vein after injection sclerotherapy. A, Incomplete mural denaturation and the damaged segments of vein reconstitute and the lumen recanalizes. B, Full mural denaturation results in the complete and permanent eradication of the vein. C and 0, The course after there has been not only full mural denaturation, but extravascular destruction of tissue. C,Although the vein disappears there will be damage to the surrounding dermis. 0, If this dermal destruction extends to the overlying epidermis, an ulcer will develop that is likely to result in textural change. Figure 2. Dilated blue-green veins demonstrate incompetent reticular varicose veins. They reside in the subcutaneous fat and are clinically dilated and hemodynarnically incompetent. Figure 3. Tortuous, protruding veins demonstrate varicose veins. They reside within or deep to the subcutaneous fat and are clinically dilated and hernodynamically incompetent. Figure 4. These photographs juxtapose a 33 gauge needle next to capillaty telangiectases (A) and venous telangiectases (B). It is apparent that capillary telangiectases are more narrow than the cannula of even a 33 gauge needle, making it impossible to properly cannulate the vessel.
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A
B
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D Figure 1.
Figure 2.
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Figure 3.
6 Figure 4.
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Figure 5.
B
A
Figure 8.
A
6 Figure 10.
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B Figure 11.
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B Figure 12.
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Figure 5. Retrograde venous blood flow into the hub of the needle indicating proper intraluminal cannulation of the vein. Figure 8. Before and after sclerotherapy. Figure 10. Before and after sclerotherapy. Figure 11. Before and after sclerotherapy. Figure 12. Before and after sclerotherapy.
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Deep Venous System This system includes all veins that are located within and around muscles and are surrounded by the deep fascia. These veins are the primary course through which at least 90% of the venous blood from the lower extremity is transported pr0ximal1y.l~
Perforating Veins This component includes veins that course transversely in the lower extremity (the veins of the superficial and deep venous system are primarily axially oriented). They directly connect the above two venous systems and normally transport blood from the superficial to the deep veins.
VENOUS SYSTEM HEMODYNAMICS OF THE LOWER EXTREMITY All competent veins have valves to insure the centripetal flow of blood. The known exceptions in the lower extremity include veins less than 1 mm in diameter; the perforating veins of the foot; and so-called oscillating reticular veins.l8 These oscillating reticular veins are valveless veins that link adjacent valved venous tributaries and are surmised to allow equilibration of blood flow and pressure in the tissue and may also play a role in thermoregulation. They have been identified especially on the thigh but may be a ybiquitous component of the cutaneous vasculature. Under normal circumstances axially oriented veins transport blood proximally, and transversely oriented veins transport blood from the superficial to the deep venous system. When veins become incompetent their normal unidirectional, centripetal flow of blood is disturbed and they then permit blood to flow in a retrograde direction, depending upon the gravitational force to which intraluminal blood is subjected. This retrograde flow produces elevated intravascular pressure that progressively promotes vein distension, dilatation, and tortuosity. If elevated venous pressure is transmitted more proximally in the vascular circuit (i.e., in a retrograde direction) it may result in elevated intracapillary hydrostatic pressure. When elevated intracapillary hydrostatic pressure is transmitted to the surrounding tissue it may result in what is referred to as the cutaneous changes of venous insufficiency.
TYPES OF VASCULAR ECTASIAS OF THE LOWER EXTREMITY All visibly and palpably dilated veins of the lower extremity are part of the superficial venous system. That is, these are veins superficial to the deep fascia, and are usually located in the dermis or subcutaneous fat. Most superficial venous insufficiency (i.e., varicose veins or venous telangiectases) is present without clinically apparent deep venous insufficiency. Even if veins of the deep venous system should become dilated and incompetent they do not become clinically apparent, visually or by palpation. However, their incompetence may be manifest by the resulting cutaneous changes of venous insufficiency (i.e., venous stasis dermatitis, venous ulceration, dermatoliposclerosis). There are arbitrarily 3 types of clinically ectatic, functioning incompetent blood vessels of the lower extremity for which patients seek treatment. These include varicose veins, telangiectatic veins, and telangietatic capillaries. Knowledge of the differences between these dilated blood vessels is necessary in order to appropriately and effectively treat them.
Varicose Veins This group includes the largest diversity of ectatic veins based upon their size and depth below the surface. These are ectatic veins that are greater than 2 millimeters in diameter and may exceed 2 centimeters in diameter. They may protrude above the plane of the skin and often follow a tortuous course. Those that reside in the deep dermis and subcutaneous fat often appear blue-green in color and they represent varicosities of reticular veins (Fig. 2).17When varicosities reside in the subcutaneous fat or deeper, the overlying skin may be too thick for any intraluminal blood to be visualized and, having no apparent color, they may merely protrude above the skin plane. They may represent varicosities of the saphenous veins or their larger tributaries (Fig. 3). Many physicians and patients alike incorrectly refer to large, nodular varicosities as being deep varicose veins when in fact they are constituents of the superficial, not deep, venous system.
Telangiectatic Veins These are ectatic veins that are up to 2 millimeters in diameter. They usually appear
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reddish-blue or blue in color and they reside in the dermis. Many people commonly refer to them as spider veins. Telangiectatic Capillaries These are ectatic capillaries that are usually less than 0.2 millimeter in diameter. They appear red or pink in color and reside in the papillary dermis. Many people commonly refer to them as broken blood vessels. It is important to be able to distinguish capillary telangiectases from venous telangiectases. While varicose veins and venous telangiectases respond to sclerotherapy, capillary telangiectases usually do not. Not only are capillary telangiectases relatively unresponsive to sclerotherapy, but the development of telangiectatic capillary matting is commonly observed as an adverse effect when one attempts to treat them by sclerotherapy. With experience it becomes quite easy to distinguish capillary from venous telangiectases (Fig. 4). Since capillary telangiectases are usually less than 0.2 millimeter in diameter, they are more narrow than the cannula of a #33 gauge needle (which has an outer diameter of 0.2 millimeter). However, as a general rule, any telangiectasia with a diameter more narrow than a #30 gauge needle (which has an outer diameter of 0.3 millimeter) is probably a capillary telangiectasia-not a venous telangiectasia-and treatment should proceed with caution since they are unlikely to respond and their treatment is associated with a greater incidence of adverse effects. The treatment of telangiectatic capillaries can be attempted by photothermal coagulation with a vascular laser, i.e., a laser in which hemoglobin is the chromophore. Needles can be used to estimate the diameter of ectatic vessels. The cannula of a needle is described in terms of its gauge. The corresponding outer diameter, in millimeters, is given in the following chart: gauge: 33 30 27 25 21 18 width (mm): 0.20 0.30 0.41 0.51 0.90 1.27 INITIAL CONSULTATION An initial consultation is scheduled prior to any treatment visits. The purpose of this consultation is to determine the nature of a patient’s venous disease (i.e., superficial venous system insufficiency, deep venous system insufficiency, or both); the type of ectatic
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superficial vessels present (i.e., varicose veins, venous telangiectases, or capillary telangiectases); the extent of the problem (i.e., few or numerous; localized or widespread; discrete or grouped); and whether the patient is an acceptable candidate for treatment. It is also an opportunity to understand the patient’s expectations from treatment, inform her of results that can realistically be achieved from treatment, and insure that she has an understanding of, and willingness to accept, the possibility of adverse effects. The following exchange of information transpires during this pretreatment consultation. History The patient is queried regarding the age of onset of her ectatic veins; whether there were any associated events around the time of their development, i.e., pregnancy or trauma; the presence of any symptoms that she attributes to these veins; family history of venous disease; history of deep venous thrombophlebitis; and any other relevant information. The development of hyperpigmentation after even mild trauma is of interest as is the tendency towards bruising. Patients who bruise easily tend to be somewhat more inclined to linear postsclerotherapy hyperpigmentation (see Minimizing Complications: Hyperpigmentation later in text). The author always inquires as to which ectatic veins the patient wants removed. Often patients are only interested in removing ectatic veins at a particular site, i.e., below the knees, or of a particular size, i.e., only varicose veins and not venous telangiectases. It is important to know which ectatic veins the patient wants removed so that an estimate of the total number of treatment sessions can be provided at the conclusion of the consultation. Clinical Examination The lower extremities are examined to determine the extent of venous disease and the type of ectatic blood vessels that are present (see Types of Vascular Ectasias of the Lower Extremity earlier in text). The skin is examined to determine not only the presence of any cutaneous changes of chronic venous insufficiency but also any other skin lesionswhether or not they may be secondary to venous disease.
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All skin changes and lesions are noted including, for example, the presence of actinic damage, melanocytic nevi, lentigines, dermatofibromas, and pigmentary alteration. After treatment has been initiated, most patients have a heightened awareness of their treated veins and the adjacent skin. Many have a tendency to attribute pre-existing lesions (which they never previously noticed) to sclerotherapy . Varicose veins are palpated and balloted to clinically determine if they are being subjected to significantly elevated venous pressure. Significantly elevated venous pressure in varicose veins is an indication of reflux from the deep venous system. Noninvasive Vascular Testing
A thorough discussion of noninvasive vascular testing is beyond the scope of this article. However, this diagnostic testing can be valuable in the evaluation of the extent of venous insufficiency, and in determining if surgical intervention will be beneficial, i.e., in the presence of venous reflux from the deep into the superficial venous system. Noninvasive vascular testing is indicated to confirm a clinical suspicion of deep venous system incompetence and in determining the presence and location of venous reflux from the deep venous system into the superficial venous system (i.e., at a saphenofemoral or saphenopopliteal junction or through perforating veins). Routine duplex ultrasound scanning and plethysmographic testing of patients with uncomplicated venous telangiectases and varicose veins, i.e., without any clinical evidence of deep venous insufficiency nor of any clinically significant reflux from the deep venous system into the superficial venous system, are unnecessary. Explanation of the Procedure
All aspects of sclerotherapy are thoroughly explained including a brief discussion of the mechanism of action of sclerotherapy. It is emphasized that sclerotherapy irreversibly alters the vein by dissolving the mural layers. This is followed by the resorption of the unwanted veins-they are not merely being collapsed or plugged by the solution. The patient is informed of the postsclerotherapy course
and the requirement for compression, after the treatment of either varicose veins or prominent venous telangiectases. It is made clear to the patient that it can take several weeks to several months for the body to resorb treated veins. If she expects her veins to be gone after just a few days or weeks, she may be quite disappointed with the treatment. Potential adverse effects such as postsclerotherapy hyperpigmentation and telangiectatic capillary matting are discussed and photographs are shown. Although less common, the patient is informed of the possibility of cutaneous necrosis and subsequent scarring. Patients who are pregnant or breast feeding are never treated even though no teratogenic nor mutagenic effects of sclerosing agents have ever been demonstrated.
Discussion of Treatment Plan
The estimated number of treatment sessions is outlined as is the interval between them. If a patient is concerned about the development of postsclerotherapy hyperpigmentation she may wish to wait 1 month-to observe if this develops-before pursuing additional treatment. However, if this is not a concern, in this author’s experience a safe interval between treatment sessions is 48 hours if the maximal recommended dose of a sclerosing agent is administered during each treatment. The pharmacokinetics of the two FDA approved sclerosing agents is unknown (ESI-Lederle, Inc., Philadelphia, PA, 1997 and Glenwood-Palisades, Tenafly, NJ, 1997, personal communication). In those instances when postsclerotherapy compression is required, i.e., for varicose veins and prominent venous telangiectases, the patient is informed of the duration that gradient compression hose is recommended. This may range from several days to 2 months, and rarely longer. Written postsclerotherapy instructions and a sclerotherapy consent form are reviewed with the patient and copies are given for her to review at home. This consent form includes information on the nature of the procedure and possible adverse effects. If she decides to undergo treatment, she is requested to bring the signed consent form with her to the office at the time of her first treatment session.
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DOCUMENTATION Chart Notes All pertinent positive and negative history and clinical findings should be included. These notes should document the appearance, distribution, and extent of ectatic veins. For larger varicose veins this author always includes a subjective estimate of the degree of elevated intravascular pressure, i.e., mild, moderate, or firm, as is discerned on palpation and ballottement of the veins. Also noted is the presence of pre-existing capillary telangiectases, alteration in pigmentation, and any nearby cutaneous lesions (as noted in Initial Consultation: Clinical examination earlier in text). These changes are shown to the patient prior Zo treatment and this is noted as well. The records should indicate that the procedure and the possible adverse effects were thoroughly explained to the patient. If the patient seems to be at increased risk of developing adverse effects, she should be told of this in advance and this should be included in the notes.
Photodocumentation Pretreatment photographs are invaluable and should be taken of every treatment site. We all have very short memories and most patients rarely remember the pretreatment appearance of their veins. Pre-existing skin lesions, which were never noticed by the patient, are often first observed after, and incorrectly attributed to, treatment.
Informed Consent A signed copy of the informed consent form that had been reviewed with the patient at the time of the initial consultation, and which she has had an opportunity to review at home, should be part of the records.
PRETREATMENT PREPARATION After the initial consultation, the patient may schedule an appointment for a treatment session. The patient should not have applied any cream, lotion, or bath oil to her lower extremities after her last bath or shower. These products make piercing the skin diffi-
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cult when attempting to cannulate the vein. In addition, no coverup makeup should be applied over any veins that the patient wants treated. Makeup makes it difficult to visualize the veins and estimate their depth. There is no need to discontinue any drug with anticoagulant or antithrombotic activity. These agents do not increase vessel fragility and should not affect treatment technique nor the concentration of the sclerosant to be injected.” There will only be increased ecchymoses if blood inadvertently extravasates from the vein during treatment.
INITIAL TREATMENT VISIT If she has not already done so, the patient is asked to sign the sclerotherapy consent form. Pretreatment photographs are taken. If gradient compression hosiery will be required, the patient is measured. An inventory of these stockings is maintained in the office so that they can be applied immediately after treatment. If more than one treatment session will be required, this author usually begins with the most prominent and unsightly of veins that the patient wants removed. As a general rule, larger veins are treated initially and smaller veins are treated during subsequent sessions in decreasing order of size. At the end of the treatment session the postsclerotherapy instructions are reviewed.
SCLEROTHERAPY TECHNIQUE Sclerotherapy is an exquisitely techniquesensitive procedure. If veins do not respond to treatment, it is usually a result of inadequate technique and not any inherent limitation of the procedure. Treatment of varicose veins is similar to that of venous telangiectases. However, the application of external compression is usually vital after the injection of varicose veins while it is often unnecessary after treating venous telangiectases. (See Sclerotherapy Technique: Postsclerotherapy compression, later in text).
lntravascular Injection It is mandatory that the sclerosant is injected intravascularly. Extravascular injection can produce necrosis with almost every
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available sclerosant (hydroxypolyethoxydodecane is the e~ception).~ Even if necrosis is unlikely to develop, there is an increased incidence of adverse effects, i.e., hyperpigmentation and telangiectatic capillary matting, after extravascular deposition of a sclerosant. The intravascular deposition of sclerosant requires the intravascular localization of the needle cannula and needle tip. This is confirmed by observing passive retrograde flow of blood into the needle hub or syringe barrel (Fig. 5). Once this is established, injection can proceed. Volume of lnjectate
The volume of sclerosant to inject into a vein depends upon the vein's volume. If there are numerous tributaries, injection can continue until all of the veins have been exposed to the solution. For large varicose veins, often the maximum quantity of sclerosant that can be safely administered during any one treatment session is given into one puncture site. Additional varicosities can be treated during subsequent sessions. More important than the volume or rate of injection is the duration of direct contact the sclerosant has with the luminal surface of the vein. Concentration of lnjectate
The concentration of the injected sclerosant should depend upon the mural thickness of the vein. Mural thickness is directly correlated with the lumen diameter. That is, the wider the diameter of the vein the greater is its wall thickness and the higher should be the concentration of the injected sclerosant. The appropriate concentration of sclerosant will also depend upon whether the sclerosant is being diluted by any intravascular blood (see Sclerotherapy Technique: Empty vein technique, later in text). Even if the sclerosant is too dilute to effect full mural destruction it may nonetheless produce enough mural disruption to be thrombogenic. However, ultimately the vein walls will be reconstituted, the lumen will be recanalized, and the vein will reappear. Cannulation of the Vein
Cannulation of a vein should always be brisk to insure minimal trauma to the vein.
This minimizes the chance of extravasation of both sclerosant and blood. Prior to inserting the needle into the skin, the cannula should be bent at the hub so that the syringe can be comfortably held while the cannula remains parallel to the skin (Fig. 6). The bevel of the needle should always be up and not to the side. If the vein cannot be cannulated, or if the needle tip is no longer intravascular, injection should not proceed or cease, respectively. If a telangiectatic vessel is too small to be cannulated by a #30 gauge needle, it is likely a telangiectatic capillary and not a telangiectatic vein. In this author's experience, telangiectatic capillaries respond poorly to sclerotherapy and their injection is associated with a high incidence of telangiectatic capillary matting and necrosis, compared to the treatment of venous telangiectases. Empty Vein Technique
When treating varicose veins, the empty vein technique should be employed.'j,l5 That is, the leg should be elevated to at least a horizontal level to minimize the volume of blood within the intraluminal space. Blood only dilutes the sclerosant, rendering it less potent. If the sclerosant is diluted, it may not produce sufficient mural destruction to result in vein resorption and the vein will persist. In addition to employing this empty vein technique, postsclerotherapy compression is important to minimize the volume of any thrombus that develops within the intraluminal space after treatment. Even if full mural destruction is achieved, without significant compression, blood will seep into the intraluminal space, become coagulated, and prolong the time for the complete resorption of the vein. Postsclerotherapy Compression
Immediate application of external compression after injection is important to minimize the return of blood into the treated vein. This minimizes the volume of the formed thrombus. Thrombosis not only prolongs resorption time, but predisposes to symptomatic superficial thrombophlebitis. In this author's experience, ectatic veins less than two millimeters in diameter usually do not benefit from postsclerotherapy compression. That is, gradient
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Figure 6. A depicts how the cannula of the needle should be bent so that it remains parallel to the plane of the skin and veins during injection. 6, If the cannula is not bent, it is difficult to impossible to maintain plane of the skin and veins, while trying to comfortably hold the syringe.
compression hosiery does not diminish the volume of interluminal thrombus that develops after treatment of these smaller veins. However, it is indicated for those treated veins greater than 3 millimeters in diameter, and significantly reduces the volume of the intraluminal thrombus that develops after treatment of larger veins. For those veins that are 2 to 3 millimeters in diameter, the need for compression is determined on an individual basis. Compression is most effectively achieved with gradient compression hosiery and is well tolerated by almost all patients. Most patients will achieve adequate compression with Class 2 (30 mmHg to 40 mmHg) hosiery. For very high pressure varicosities Class 3 (40 mmHg to 50 mmHg) hosiery may be required. The location of the varicosities will determine whether the hosiery must extend as high as the knee, mid-thigh, full-thigh or be pantyhose. The pressure that describes gradient compression hosiery (in millimeters of mercury) is the pressure exerted at the level of the ankle. The pressure exerted at the level of the calf would be 70%, along the mid thigh 50%, and along the upper thigh only 40% of that at the ankle. For example, a stocking with a
pressure of 30 mmHg to 40 mmHg will exert a pressure of 21 mmHg to 28 mmHg at the calf (70%), 15 mmHg to 20 mmHg at the mid thigh (50%) and 12 mmHg to 16 mmHg at the upper thigh (Fig. 7). If compression hosiery is recommended, the patient must be cautioned that foot discomfort (i.e., pain, cramping, numbness) may be experienced, especially with leg elevation. When it occurs, it is usually at bedtime and the patient may be awakened from sleep. These symptoms are readily ameliorated when the leg is dependent, as with standing and walking. This pain represents tissue hypoxia, i.e., iatrogenic claudication. It results from external compression and diminished arterial flow at the ankle. While standing, this reduction in arterial pressure to the foot is insignificant. However, in the elevated position, when the arterial pressure at the ankle is no longer augmented by the gravitational hydrostatic force exerted on this long column of blood, this reduction in arterial blood pressure can become significant. If pain is experienced when the patient stands, either the stocking is too tight or the patient’s arterial supply is diminished, i.e., arteriosclerosis is present, and external compression should not be applied.
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maximum 40%
maximum 50%
cn
ized examination table will be comfortable for the patient and will also make it easy to move the patient so that all veins will be easily accessible without the need for the physician to contort while injecting. A stool with wheels will make it easier for the physician to be seated and comfortably positioned while treating the patient. Adequate overhead lighting is invaluable for visualizing veins. It is much easier to visualize veins under fluorescent lighting compared to incandescent lighting. Specifically, cool white fluorescent light (rated at 4100" Kelvin or cooler) highlights the blue-green color of veins.
00%
Syringes Figure 7. The progressive proximal decrease in exerted pressure with gradient compression stockings. At point d, just below the knee, the external pressure is 70% of that at the ankle; at point f, along the mid thigh, it is 50% of that at the ankle; at point g, along the upper thigh, it is 40% of that at the ankle. (Courtesy of MediUSA, Arlington Heights, IL.)
Contrary to some recommendations, the application of gauze pads or cotton taped to the overlying skin provides no significant external compression. Although elastic bandages can be applied, they have disadvantages compared to gradient compression hosiery: Elastic bandages loosen considerably and the adequacy of compression is unpredictable; once removed by the patient, i.e., to bathe, they are not usually reapplied as tightly by the patient; if the patient does keep the elastic bandage wrapped tightly enough, it may act like a tourniquet, and distal swelling (especially of the foot and ankle) should be expected. SUPPLIES
Injection sclerotherapy requires few supplies and rarely any high technology instrumentation. However, carefully selecting those supplies and equipment will make treatment less tedious and laborious and may enhance treatment techniques. Treatment Environment
A well-lit treatment environment is most conducive to a successful outcome. A motor-
Three-milliliter syringes are most practical. They hold an adequate volume of solution to treat many small veins or a larger varicose vein. They fit comfortably in a hand compared to smaller and larger volume syringes. Fine control of the plunger is usually easier than with a 1 milliliter syringe. Choosing the best syringe will require testing of several different brands. A syringe in which there is consistent and acceptable plunger resistance through the entire length of the barrel is the syringe that should be used. Most syringes have rubber or latex stoppers at the end of the plunger. Some sclerosants or their preservatives can dissolve latex and the physician can feel an increase in the resistance of the plunger as it travels through barrel. This is most commonly observed with those solutions of polidocanol (hydroxypolyethoxydodecane) that contain chlorobutanol (trichloroisobutyl alcohol) as a preservative. If this occurs, it will be necessary to discard the syringe after each 3 milliliters is injected or to use glass syringes. This author does not find glass syringes helpful since the plunger resistance is usually not as constant and consistent as it courses through the barrel, compared to plastic syringes. Needles
These serve as a conduit for the sclerosing solution. They should be sharp to minimize pain, penetrate tissue easily, and minimize trauma to the vein. Unfortunately, needles dull easily. If a dull needle is used to cannulate a vein, it may tear rather than pierce the
SCLEROTHERAPY TREATMENT INSIGHTS
vein wall. This can lead to leakage of sclerosant or blood into the surrounding tissue. For optimal vein penetration, a needle should be discarded after 1 to 2 injections. There is a great disparity in the quality of different brands of needles. The finest needles have very sharp tips with no burrs. Needles with burrs on their tips d o not permit a smooth entrance into the skin and vein. It will be necessary to experiment with different brands of needles to determine which manufacturer consistently produces the highest quality needle. This author has found that the most expensive needles are not necessarily of the highest quality. The vast majority of veins that will be injected-no matter how large or small-can be treated with needles that are either 27 gauge or 30 gauge X 1/2 inch.
Magnification Cannulation and injection of a vein require careful visualization. Magnification greatly aids in the process of vein cannulation and confirmation of the intraluminal localization of the needle tip. This author usually uses 3.0 diopters of magnification, or greater, which provides a working distance of 30 centimeters to 40 centimeters.
Sclerosant The sclerosant of choice is usually the one with which the physician has the greatest experience. However, if this author was to choose only one sclerosant to use it would be polidocanol (hydroxypolyethoxydodecane). This is a nonionic surfactant that is commercially available in several concentrations including 0.5'10, LO%, 2.0%, 3.0°/o, and 5.0%. Polidocanol may be diluted to any concentration that the physician feels is appropriate using a sterile solution of 0.9% sodium chloride. It can be used to treat any ectatic vein encountered on the lower extremity-from the smallest venous telangiectasia to the largest varicose vein. The 5.0% solution is quite potent and will easily be able to destroy the full mural thickness of even the largest varicosity. When diluted to as low as 0.1%, it can be used to treat the smallest and most fragile of venous telangiectases. It is painless to inject.* And, unlike all other sclerosants, polidocanol will not produce ulceration or necrosis if ex-
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travascular tissue is exposed to this agent. However, like every other sclerosant, it may be associated with extravascular necrosis and ulceration in spite of appropriate intravascular injection. The underlying cause of ulceration after intravascular injection is still not established but there are several possible explanations (see Minimizing Complications: Cutaneous necrosis later in the text). Polidocanol is not an FDA approved sclerosant. Another commonly used sclerosant is sodium tetradecyl sulfate, which is an anionic surfactant. At an equal concentration it is somewhat more potent than polidocanol. Sodium morrhuate, also an anionic surfactant, has been used for more than 60 years. It is quite a potent sclerosant and is recommended for treating only varicose veins, but not recommended for treating venous telangiectases. Sodium tetradecyl sulfate and sodium morrhuate are the only FDA approved sclerosants for treating vascular ectasias of the lower extremity. Hyperosmotic sclerosants, such as hyperosmotic sodium chloride, have been used for many decades. It is commercially available as a 23.4% solution (4 milliequivalents/milliliter). Although not FDA approved as a sclerosant, it is an FDA approved abortifacient. Hyperosmotic solutions have several disadvantages: they are weaker than the surfactant sclerosants and therefore are less effective for larger, thicker-walled, veins; they are usually quite painful to the patient during intravascular infusion; they are likely to produce necrosis in extravascular tissue; their range of effective concentrations is much more limited compared to the surfactant sclerosants, i.e., hyperosmotic sodium chloride is useful over a less than 3-fold range in concentration (from 12% to 30%) compared to a 50-fold range for sodium tetradecyl sulfate or polidocanol (0.1% to 5.0%).
POSTSCLEROTHERAPY ACTIVITY Immediately after treatment, patients may resume all normal activities including walking and standing. In those patients treated for venous telangiectases this includes even strenuous activity, (i.e., jogging, aerobic exercise, and swimming) may resume. It has been this author's experience that the level of the patient's activity after treatment does not affect the volume of postsclerotherapy intravas-
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cular thrombosis within the treated venous telangiectases. After treating larger channel varicosities, i.e., greater than 3 millimeters in diameter, this author has found that limiting strenuous activity, i.e., jogging and aerobic exercise, for the first 24 to 48 hours (depending upon the size of the varicosities and their intraluminal pressure) limits the degree of postsclerotherapy intravascular thromboses within the treated varicose vein. After this initial 24 to 48 hour period as long as the gradient compression hosiery is worn, the patient may resume all activities. It has been recommended in the past that patients walk an arbitrary distance, i.e., 3 miles, immediately after treatment and daily for some time thereafter.12 Many physicians continue to promote this posttreatment regimen. The rationale for this recommendation is that walking reduces the volume and pressure of blood in the treated vein and stimulates fibrosis. In addition, it has been thought that immediate ambulation following injection prevents any intimal damage within deep veins from becoming a site for propagation of thromb~sis.'~ There has never been any scientific evidence nor any controlled studies to justify this recommendation. This author has not found any differences in the rates of vein resorption whether or not the patient walks for an arbitrary time or distance each day. Neither has this author ever seen a patient who has developed any clinical indications of deep vein thrombosis in the absence of any specific postinjection regimen of ambulation or activity.
MINIMIZING COMPLICATIONS Employing scrupulous injection techniques will insure minimal risk of adverse effects. However, even the most dexterous and meticulous sclerotherapist will have patients who sustain adverse effects. Commonly occurring adverse effects include the development of hyperpigmentation, telangiectatic capillary matting, and superficial cutaneous necrosis resulting in scar formation. Complications can be expected when less than optimal techniques are employed. For example, complications are common if there is inadvertent extravascular injection or if too concentrated a solution is injected than is required for the vein being treated. Both circumstances may be associated with develop-
ment of excessive inflammation or necrosis at the treatment site or along the course of the treated vein. In general, complications can be minimized by injecting: the lowest appropriate concentration of solution; the lowest appropriate volume of solution; at the slowest rate; and at the lowest pressure. In those patients predisposed to the 2 most commonly occurring adverse effects, i.e., hyperpigmentation and telangiectatic capillary matting, following these guidelines will minimize but not prevent them from developing. Patients who are predisposed to these adverse effects should be forewarned that if such side effects are sustained after one treatment, they are likely to occur after each subsequent treatment.
Hyperpigmentation An incidence of postsclerotherapy hyperpigmentation of 30% is not uncommon, even with the most scrupulous of techniq~es.'~ It appears as linear tan to brown pigmentation along the course of the treated vein and is the result of hemosiderin deposition? Sometimes melanin contributes to this pigmentation due to its incontinence from the overlying epidermis resulting from underlining dermal inflammation surrounding the treated vein. Minimizing the amount of blood in the treated vein, i.e., the empty vein technique, and minimizing venous return after injection will help reduce the incidence of this problem. For larger veins, this requires postsclerotherapy compression for an adequate period of time. For venous telangiectases, postsclerotherapy compression is not as effective in reducing the incidence of this problem as it is for larger veins. Hyperpigmented patches at injection sites are usually due to extravasation of blood. Such extravasation commonly occurs with poor technique and is usually preventable. Fortunately, hyperpigmentation resolves in almost all patients but can take months and sometimes years before it completely disappears.
Telangiectatic Capillary Matting An incidence of telangiectatic capillary matting of 16% to more than 50% has been reported even when the procedure is carefully and properly performed.', In those pre-
SCLEROTHERAPY TREATMENT INSIGHTS
disposed, it is impossible to prevent this problem. It seems to be more common in those who are fair complected, especially those who have telangiectatic matting, or at least capillary telangiectases, in the vicinity of the treatment site. It will commonly develop if excessive inflammation develops at the treatment site. Although some authors have not found this adverse effect to occur in men; this author has observed telangiectatic capillary matting as an adverse effect in men as well as in women. Such excessive inflammation frequently develops if too concentrated of a sclerosant is injected for the caliber of the telangiectatic veins being treated. If a patient seems predisposed to this problem it is wise to inject a solution that is somewhat more dilute than would otherwise be injected into similar caliber veins in a nonpredisposed person. Certain locations, such as the distal medial thigh, seem especially prone to this adverse effect. Unlike hyperpigmentation, which eventually completely resolves in almost all patients, telangiectatic capillary matting may persist.'O It is difficult to know the incidence of capillary telangiectatic matting and the rate at which it spontaneously involutes since the frequency with which this is observed is dependent upon the vigilance of the observer.
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If telangiectatic matting does persist, treatment can be attempted through photothermal coagulation using a laser that treats vascular ectasias.
Cutaneous Necrosis There are several mechanisms that can account for the development of this adverse effect. It may be seen not only with inadvertent extravascular injection but after correct intravascular injection. If a sclerosant (other than polidocanol) seeps into the extravascular tissue, necrosis may occur. The likelihood of necrosis will depend upon the particular sclerosant injected and the volume and concentration that extravasates. Meticulous technique should minimize the incidence of extravasation. However, necrosis seems to occur even more commonly in the absence of extravasation of sclerosant, i.e., after proper intravuscuZar injection. Intense blanching of the surrounding skin or at a distant site during injection is a warning that this problem is likely to develop. The pathophysiology of this complication is not certain but is most likely from either intense vasoconstriction or retro-
Figure 9. Before and after sclerotherapy.
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Figure 13. Before and after sclerotherapy.
grade flow of sclerosant, which damages the more proximal end arterioles. Either mechanism will cause tissue hypoxia and subsequent necrosis. Any sclerosant can be implicated, including polidocanol. If blanching is noted at the time of treatment, injection should immediately cease and the involved skin gently massaged. Some have claimed that the application of a cutaneous vasodilator, such as nitroglycerin ointment, reduces the development or extent of subsequent necrosis.1° Well controlled studies have never been performed so it is unclear if this can really reduce the incidence or extent of ulceration. However, it is worthwhile applying this ointment if cutaneous blanching appears and is sustained, i.e., persists even though injection has ceased. If devitalization of tissue seems likely, or has developed, the area should be treated with a wound dressing material or the application of an occlusive ointment to prevent desiccation of tissue and promote wound healing by secondary intention. These ulcers often take two months or longer before they have re-epithelialized. There is usually alteration in skin texture, i.e., scarring. Patients require reassurance regarding the eventual healing of these sites and should be told at the onset that healing will be prolonged so that they do not lose confidence in
the appropriateness of the care the physician is recommending. Sclerotherapy remains a safe and effective procedure to permanently eradicate ectatic veins as is demonstrated in the clinical examples in Figures 8 to 13. References 1. Davis LT, Duffy DM: Determination of incidence and risk factors for postsclerotherapy telangiectatic matting of the lower extremity: A retrospective analysis. J Dermatol Surg Oncol 16:327-330, 1990 2. Duffy D M Small vessel sclerotherapy: An overview. Adv Dermatol3221-242, 1988 3. Duffy DM: Understanding sclerotherapy. In Lask GP, Moy RL (eds): Principles and Techniques of Cutaneous Surgery. New York, McGraw-Hill, 1996, pp 403417 4. Fegan G: Varicose Veins: Compression Sclerotherapy. Hereford, Berrington Press, 1990, p vii 5. Fegan G: Varicose Veins: Compression Sclerotherapy. Hereford, Berrington Press, 1990, p 89 6 . Fegan WG: Continuous compression technique of injecting veins. Lancet ii:109-112, 1963 . 7. Goldman MP: Sclerotherapy: Treatment of Varicose and Telangiectatic Leg Veins. St. Louis, MosbyYearBook, 1991, p 61 8. Goldman MP, Bennett RG: Treatment of telangiectasias: A review. J Am Acad Dermatol17167-182,1987 9. Goldman MP, Kaplan RP, Duffy DM: Post-sclerotherapy hyperpigmentation: A histologic evaluation. J Dermatol Surg Oncol 13:547-550, 1987
SCLEROTHERAPY TREATMENT INSIGHTS 10. Goldman MP, Sadick NS, Weiss RA: Cutaneous necrosis, telangiectatic matting, and hyperpigmentation following sclerotherapy: Etiology, prevention and treatment. Dermatol Surg 21:19-29, 1995 11. Green D Compression sclerotherapy techniques. Dermatol Clin 7137-146, 1989 12. Green D: Mechanism of action of sclerotherapy. Semin Dermatol 12:8%97, 1993 13. Green D: Sclerotherapy for the peramanent eradication of varicose veins: Theorectical and practical considerations. J Am Acad Dermatol (to be published) 14. Kosinski C: Observations on the superficial venous system of the lower extremity. J Anat 60131-142, 1926
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15. Linser K: Die behandlung der krampfadem mit intravarikosen kochsalzinjektionen (The treatment of varicose veins with intravenous injections of tabIe salt). Dermatologische Wochenschrift 81:1345-1351, 1925 16. Norris MJ, Carlin MC, Ratz JL: Treatment of essential telangiectasia: Effects of increasing concentrations of polidocanol. J Am Acad Dermatol 20:643-649, 1989 17. Somjen GM: Anatomy of the superficial venous system. Dermatol Surg 21:3545, 1995 18. Taylor GI, Caddy CM, Watterson PA, et al: The venous territories (venosomes) of the human body: Experimental study and clinical implications. Plast Reconstr Surg 86:185-213, 1990
Address reprint requests to David Green, MD 4800 Montgomery Lane, #M50 Bethesda, MD 20814