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Venous malformation of the pediatric airway
lHTE.RNATKlNN
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Venous malformation Laurie A. Ohlm+*,
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of the pediatric airway’
James Forsen”, Patricia E. Burrowsb
“Department of Otolaryngology, Children’s Hospital, Harvard Medical School, Boston MA, USA bDepartment qf Radiology, Children 5 Hospital, Harvard Medical School, Boston MA, USA Received 29 February 1996; revised 29 April 1996; accepted 1 May 1996
Abstract Objective: To evaluate the management of venous malformations of the pediatric airway, including diagnostic criteria and response to sclerotherapy and laser photocoagulation. Design: Case series analysis of eight patients diagnosed with venous malformations of the upper airway. Setting: Academic, tertiary care, children’s hospital. Patients: Eight patients (3 female, 5 male) with congenital venous malformations of the upper airway. Intervention: Each patient underwent an individualized treatment regimen of sclerotherapy, laser photocoagulation and/or surgery. Results: The combination of sclerotherdpy and laser photocoagulation appears to cause gradual regression of the malformation. Five of the eight patients will require further therapy; two patients remain tracheotomy dependent. Conclusions: Extensive venous malformations of the pediatric airway require staged therapy, with a combination of sclerotherapy and photocoagulation. Long-term follow-up is essential because of the natural history of these lesions. Keywords:
Airway;
Pediatric;
Venous malformation
* Corresponding author, Department of Otolaryngology, Texas Children’s Hospital, 6621 Fannin St., Houston, TX 77030, USA. Tel.: + 1 713 770 3268; fax: + 1 713 770 3251. ’ Presented at the American Society of Pediatric Otolaryngology, Durango, Colorado, 28 May 1995. 01655876/96/$15.00 8 1996 Elsevier Science Ireland Ltd. All rights reserved PII SO165-5876(96)01382-l
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1. Introduction Vascular birthmarks are common in the head and neck. Most cause no interference with cosmesis or function and require no treatment. Other vascular lesions are larger and create significant problems, depending on location and size. Confusing terminology exists in the literature to describe these vascular anomalies in children. In 1982, Mulliken and Glowacki detailed a classification based upon clinical behavior and endothelial cell characteristics. Their system will be used in this paper to distinguish between the two main classes of vascular lesions, hemangiomas and vascular malformations [lo]. A vascular malformation is a collection of abnormal vessels forming a lesion that is present at birth and grows with the child. The malformation may be classified as capillary, venous, arterial or lymphatic. Combined channel anomalies are common, such as the arterio-venous malformation. Capillary, venous and lymphatic malformations are low-flow lesions, while the arterio-venous malformation is a high-flow entity. The malformation may enlarge by expansion of existing vessels, after trauma or hormonal changes; spontaneous resolution does not occur. There is no sexual predilection. In contrast, a hemangioma is a vascular tumor that enlarges by rapid endothelial cell proliferation. The hemangioma is usually not present at birth, but grows rapidly during the first year of life. The proliferative phase is followed by slow involution over the next 5-7 years. Females are more commonly affected than males. This report will focus on venous malformations of the pediatric airway. Although rare, these lesions may cause significant airway obstruction and thus require careful evaluation and treatment.
2. Materials
and methods
2.1. Technique All sclerotherapy procedures were performed in the radiology suite, under the direction of a pediatric interventional radiologist. All patients received general anesthesia, via either an endotracheal or tracheotomy tube. Cutaneous venous malformations were prepared in a sterile fashion for percutaneous injection. Airway malformations were visualized using a mouthgag or direct laryngoscopy when necessary. Direct puncture into the venous malformation was performed with a Teflon-sheathed needle (Angiocath 20-gauge, 2 inch; Becton Dickinson Vascular Access, Sandy, UT) and free flow of blood was obtained. Radiographic contrast material was then injected and the lesion was visualized with digital-subtraction serial imaging. The sclerosing agent was injected while occluding venous outflow. Sclerosing agents included 100% ethanol and 3% sodium tetradecyl sulfate (STS). The amount of agent injected was based upon the size and location of the malformation and the patient’s weight. The maximum dose of ethanol injected per
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sclerotherapy session was 1 ml/kg body weight; STS was injected to a maximum of 10 ml/session. Patients without a tracheotomy remained intubated until resolution of airway edema. All patients received dexamethasone and intravenous hydration for 24-48 h post-sclerotherapy. The neodymium yttrium aluminum garnet (Nd:YAG) laser was used to photocoagulate airway venous malformations in three patients in this series, following the technique described by Rebeiz et al. [13]. Direct laryngoscopy and the fiberoptic delivery system allowed treatment of upper airway malformations. The Nd:YAG laser was used at a power setting of 20 to 30 W, with a 0.5-1.0 s pulse duration. All procedures were performed under general anesthesia; two patients had a tracheotomy tube in place.
3. Case reports 3.1. Case # 1
This 9-year-old girl presented with a large cervical and mediastinal mass. The lesion was first noted at the age of 2 years, when a diagnosis of hemangioma was made. She was treated with steroids, with no change in the lesion. At the age of 7 years, the lesion suddenly increased in size. She developed increased shortness of breath with exertion that limited physical activity and had to sleep on several pillows. Physical examination revealed a large mass in the anterior left neck and supraclavicular areas. The mass was easily compressible and distended with a Valsalva maneuver. She had biphasic stridor in the supine position Magnetic resonance imaging (MRI) confirmed a venous malformation extending anterior and posterior to the trachea in the neck and mediastinum. The lesion surrounded the carotid, vertebral and subclavian arteries and pushed the trachea to the right (Fig. 1). Initial sclerotherapy of the anterior neck and supraclavicular region was carried out percutaneously, to place platinum coils and inject ethanol and STS. She remained intubated for several days until resolution of airway edema. Post-extubation, a mild left Horner’s syndrome and left vocal cord paresis were noted. MRI scan demonstrated thrombosis of the anterior and supraclavicular malformation, with residual lesion in the posterior mediastinum. Two months later, the remaining mediastinal malformation was treated, with placement of platinum coils and injection of ethanol. Post-treatment, a left phrenic nerve palsy was noted; hemoglobinuria resolved with hydration. Follow-up fluoroscopy 2 days later showed bilateral diaphragmatic movement. Repeat ethanol and STS injection was performed 4 months later. At last follow-up, the patient notes decreased shortness- of breath and increased activity level. 3.2. Case # 2
This 22-month-old
girl developed obstructive
sleep apnea early in life. Physical,
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examination revealed venous malformation involving the left cervicofacial region, oral cavity, anterior tongue and the base of tongue. Endoscopy demonstrated venous malformation of supraglottis (Fig. 2). The true vocal cords and trachea were clear. MRI scan confirmed the presence of a large cervicofacial venous malformation with upper airway obstruction (Fig. 3). Staged therapy was planned. Management began with oral intubation, followed by sclerotherapy. Intralesional injection of the anterior cervical malformation was performed using ethanol; the lower lip was injected with STS. Platinum microcoils were also placed in the left cervical malformation. Moder-
Fig. 1. (Patient artery (arrow).
1) Extensive
cervical
and mediastinal
venous
malformation,
surrounding
the carotid
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(arrow).
ate airway edema was observed; she was extubated 2 days later. Two months later, the midline cervical malformation had thrombosed and regressed significantly. Endoscopy revealed no change in the supraglottic lesion. Tracheotomy was performed, in preparation for further therapy. Using direct laryngoscopy for exposure, the soft palate, floor of mouth, base of tongue and left supraglottis were treated with ethanol. Three days later, the lower lip and anterior tongue were injected with ethanol. Five months later, she returned for repeat treatment. Direct laryngoscopy showed slight regression of the supraglottic venous malformation. The left supraglottis and left posterior pharynx were injected with ethanol. Three months later, tonsillectomy and adenoidectomy were performed, followed by injection of the supraglottis, anterior tongue, lower lip and submental region. Two sessions of Nd:YAG laser photocoagulation followed. The supraglottic malformation has regressed and she has been successfully decannulated. 3.3. Case # 3
This male infant was the product of a 31-week gestation, and demonstrated inspiratory stridor and difficulty feeding shortly after birth. Physicals examination revealed vascular lesions involving the right cervicofacial region, bropharupper back, penis and right lower ,extremity. Direct ynx, hypopharynx, laryngoscopy and bronchoscopy demonstrated vascular lesions of the anterior and base of tongue, lateral pharyngeal walls and soft palate. The epiglottis,
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true vocal cords and trachea were normal. MRI scan confirmed the presence of an enhancing lesion in the right cervicofacial region, with mediastinal extension (Fig. 4). The lesions were initially diagnosed as hemangiomas, and the patient received interferon cl-2a. His airway remained stable, but the lesions continued to slowly grow. After 8 months on interferon, the medication was discontinued. Biopsy of a right postauricular vascular lesion revealed venous malformation. Conservative management continued; the patient remained stable. He has some mild developmental delay, but at last follow-up (age 3.5 years) he has no respiratory or feeding problems.
3.4. Case # 4 This 4-year-old boy had a right cervicofacial and upper airway venous malformation, present since birth. After two intralesional injections, he had persistent obstructive sleep apnea. Physical examination showed venous malformation of the right face, soft palate, base of tongue and right lateral pharyngeal wall.
Fig. 3. (Patient 2) MRI demonstrates extensive left cervicofacial venous malformation.
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Fig. 4. (Patient 3) MRI scan of right cervicofacial venous malformation
(arrow).
MRI confirmed a large venous malformation with extension into the nasopharynx, floor of mouth and base of tongue (Fig. 5). A tracheotomy was performed, and he is now undergoing further sclerotherapy. 3.5. Case # 5
This 21-year-old female had undergone multiple previous treatments for an extensive left cervicofacial venous malformation, present since birth. Airway involvement included the floor of mouth, tongue, soft palate, nasopharynx and supraglottis. Prior treatment included surgical resection, sclerotherapy and tracheotomy. She was decannulated 1 year prior to referral to our institution; upon referral, she noted increasing shortness of breath. Examination and MRI scan revealed residual left cervicofacial venous malformation (Fig. 6). Flexible laryngoscopy demonstrated malformation at the base of the tongue and supraglottis, obstructing the larynx (Fig. 7). A long-standing left vocal cord paresis
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was documented. Because of increasing respiratory obstruction, a revision tracheotomy was performed. Three months later, sclerotherapy was performed using ethanol to inject the tongue, palate, left lateral pharyngeal wall and left face. Post-treatment she developed transient hemoglobinuria that resolved with hydration. Repeat ethanol injections of the oral cavity and supraglottic venous malformations were performed twice over the next 6 months. Staged surgical resection followed. Maxillary and mandibular osteotomies were performed, followed by partial excision of the malformation in the left cheek and tongue. Two months after surgery, the Nd:YAG laser was used to photocoagulate the supraglottic malformation. Three laser sessions have been performed thus far, with gradual regression of the lesion. Serial laryngoscopy with laser photocoagulation is planned over the next several months. Her tracheotomy remains in place.
Fig. 5. (Patient 4) MRI demonstrates right cervicofacial and nasopharyngeal venous malformation.
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Fig. 6. (Patient 5) MRI scan of left facial and upper airway venous malformation.
3.6. Case # 6
This 26-year-old male was diagnosed at the age of 2 years with a venous malformation extending from the right nasopharynx to the upper chest. The majority of the lesion .involved the right neck and he had undergone two prior surgical debulkings. He presented with a recent complaint of snoring and upper airway obstruction while sleeping. Physical examination, including flexible fiberoptic endoscopy, revealed an exophytic lesion involving the soft palate, right tonsillar region, right pharynx and right aryepiglottic fold. There was a large compressible mass involving the right lateral and anterior cervical regions with extension to the right chest wall. MRI revealed venous malformation anterior to the trachea, with tracheal deviation to the left. Direct laryngoscopy and bronchoscopy revealed engorgement of the lesion with the patient supine such that it nearly reached the midline of the oropharynx and hypopharynx. There was also mucosal involvement of the proximal one-third of the trachea. A polysomnogram documented moderately severe obstructive sleep apnea. The patient refused CPAP and standard tracheotomy was undesirable because of the location of the malformation.
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The patient underwent transoral injection of ethanol and STS to the right hypopharynx, oropharynx and soft palate. The cervical lesion was injected percutaneously. He remained intubated for 2 days and was extubated without difficulty. Two months post-operatively, the patient and his wife noted a much improved airway and sleep pattern, without snoring or apnea. He demonstrated mild hoarseness; laryngoscopy showed an immobile right true vocal cord in the paramedian position. Intraorally, the lesion was dramatically decreased in size. Six months post-operatively, he developed recurrent snoring, without apnea. A repeat sleep study revealed mild obstructive apnea. Further treatment is being considered. 3.7. Case # 7
This 34-year-old male had a large venous malformation involving the left face and neck, present since birth. Beginning at age 29 years, he underwent a series of fifteen sclerotherapy injections at an outside institution. A tracheotomy was placed prior to the first injection; he was decannulated several weeks later. The patient presented to our institution with a primary complaint of chronic throat and tongue pain. He also noted intermittent upper airway obstruction, especially at night. Examination revealed a large, bulky malformation involving the left face and neck, left tongue, uvula, left palate, left pharynx and laryngeal surface of the epiglottis.
Fig. 7. (Patient epiglottis (open
5) Endoscopic arrow).
view
of supraglottic
venous
malformation
(solid
arrow),
distorting
the
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He underwent two sclerotherapy injections with ethanol and STS, along with laser resection of the uvula. He remained intubated for 3 days after each treatment. After therapy, he reported general improvement in his pain and resolution of airway obstruction. He did suffer a full-thickness lower lip ulcer after ethanol injection which was treated conservatively with dressing changes. 3.8. Case # 8
This 23-month-old male presented with a 2 month history of increasing fullness in the right buccal region, without airway or feeding difficulty. Examination showed a soft, compressible mass in the buccal space. Computed tomography (CT) and MRI scans revealed a large, well-circumscribed enhancing lesion of the right masticator space. Transoral biopsy confirmed the diagnosis of venous malformation. He underwent percutaneous injection with ethanol and STS. Two months later, marked reduction in size of the mass was noted, with no residual facial asymmetry.
4. Discussion The venous malformation is a member of the family of vascular malformations. Usually a single vessel type predominates - lymphatic, capillary, venous or arterio-venous. The venous malformation is a slow-flow lesion that is present at birth and grows commensurately with the child. On physical examination, the venous malformation is a soft, compressible, non-pulsatile mass that expands with a Valsalva maneuver. Mucosal or airway lesions may demonstrate purplish discoloration and lie adjacent to normal airway structures. Rapid enlargement may occur after trauma (injury, surgery) or with hormonal changes (puberty, pregnancy). Phlebothrombosis is common and may be associated with recurrent localized pain [91.
Most venous malformations can be diagnosed after a careful history and physical examination. A venous malformation must be distinguished from another common pediatric vascular lesion, the hemangioma, which has a very different clinical course and requires other forms of treatment. In contrast to the hemangioma, the venous malformation is present at birth and will grow with the child. Spontaneous resolution is virtually non-existent. Histologic examination reveals dilated or ectatic vascular channels lined by normal endothelium; the venous malformation enlarges as these abnormal vessels undergo progressive dilatation. 4.1. Radiographic
evaluation
Radiographic studies provide further diagnostic information and are an integral part of treatment. Plain films may demonstrate the phleboliths that are commonly found in venous malformations. Secondary bony distortion may also be seen, with change in shape and increase in size of the underlying skeletal structures [7].
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Ultrasound is a simple, non-invasive modality that can identify the venous malformation as a slow-flow lesion. CT has been used in the past to delineate the extent of the lesion and map its relationship to surrounding structures. More recently, the MRI scan has added valuable information, With the use of intravenous contrast (gadolinium) and T2-weighted sequences, the radiologist can distinguish vascular malformation subtypes [2,8]. MRI evaluation of a venous malformation will demonstrate abnormal vessels of varying caliber, without intervening parenchyma. Angiography can also demonstrate the extent of vascular involvement, identify the feeding and draining vessels and document treatment response. The venous malformation is characterized by ectatic, dilated vascular spaces that fill in the venous phase and demonstrate prolonged pooling of contrast material. The malformation is a diffuse lesion consisting entirely of abnormal vessels without intervening tissue stain [3]. 4.2. Treatment Many venous malformations of the head and neck are small and asymptomatic. Supportive care and reassurance may be adequate, along with education about the natural history of these lesions. The patients should be counseled to avoid trauma and be prepared for possible hormonal changes. Other venous malformations, such as those described in this series, are much larger and cause significant airway obstruction. Lesions that impair function (airway obstruction, pain, bleeding, infection, serious cosmetic deformity) require more aggressive therapy. The goal of treatment for these malformations should be control of symptoms with conservation of normal tissues whenever possible [5]. A variety of treatment modalities have been tried throughout the years, with varying results. These include irradiation, electrocoagulation, cryotherapy, corticosteroids and compression techniques. Well-localized venous malformations may be suitable for surgical excision [l 1,121. However, resection of larger lesions is usually associated with significant blood loss and morbidity. In some cases, the venous malformation may be treated pre-operatively to decrease the size or vascularity prior to resection. Other malformations are not amenable to excision because of size and location. In these instances, alternative therapy is required. 4.3. Sclerotherapy Sclerotherapy has long been used to treat vascular lesions. This technique involves direct injection of a sclerosing solution into the center of the venous malformation, while occluding both the arterial inflow and venous outflow [9]. Many agents have been injected into venous malformations in an attempt to generate thrombosis and lead to a decrease in size and vascularity [4]. The assistance of a skilled interventional radiologist is essential. The sclerosing agent causes an intense inflammatory reaction, induces thrombosis and subsequently leads to fibrosis of the malformation [14]. Progressive fibrosis is expected to continue for 2-3 months.
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Sclerosing agents currently in use in the US include STS and absolute ethanol. STS is a synthetic anionic detergent that was originally used to treat varicose veins in the extremities [17]. Ethanol is a low viscosity agent useful for localized thrombosis. Choice of a particular sclerosing agent is based upon the location of the lesion. Ethanol is a cytotoxic agent that necroses endothelial cells quickly, and is often chosen to treat large, deep venous malformations. STS is a slightly milder agent and is used to treat more superficial malformations to decrease the risk of skin necrosis [14]. Multiple injections may be required, depending on the treatment response. If indicated, sclerosed venous malformations can be excised lo- 14 days after injection. The inflammatory response associated with sclerotherapy is intense, and significant airway edema results, resolving over 24448 h. It is crucial to protect the airway in such cases. Prolonged intubation is appropriate for some patients, while tracheotomy may be indicated for the patient who will require multiple sclerosing procedures. Sclerotherapy results in hemolysis of red blood cells within the venous malformation, with subsequent hemoglobinuria in 50% of children [2,4]. To prevent renal toxicity, intravenous fluids are administered at twice normal rates during the procedure and the recovery period [2]. Complications of sclerotherapy may occur if the sclerosing agent passes into the normal adjacent vasculature. Absolute ethanol is a potent intravascular embolic agent that can cause neuropathy and tissue necrosis [4]. Three of our patients developed post-injection nerve paresis. One (patient # 5) had long-term left vocal cord paralysis after multiple surgical and sclerotherapy procedures. Another patient ( # 6) developed ipsilateral vocal cord paralysis after transoral and percutaneous injections. The other patient ( # 1) developed a transient left phrenic nerve palsy that resolved over several days and a left true vocal cord paresis. One patient ( # 7) sustained a lip ulcer after ethanol injection that resolved with conservative therapy; none of our patients experienced permanent skin necrosis. The inflammatory response after sclerotherapy may also lead to fibrosis and scar formation. Sclerotherapy should be performed very carefully in delicate areas like the larynx. Controlled injection is essential, with superselective catheter techniques or direct percutaneous embolization [18]. 4.4. Embolization
An adjunct to sclerotherapy is the placement of intravascular embolization coils. These coils have a high thrombogenicity and create long-term vascular blockage in selected lesions. Choice of the type of coil may depend on plans for follow-up radiographic imaging. Steel and platinum coils cause significant imaging artifact on CT scans. Steel, which is ferromagnetic, also creates an artifact on MRI. Platinum is non-ferromagnetic and causes fewer problems on MRI scan; platinum coils should be used when follow-up MRI scans are anticipated [16]. 4.5. Laser therapy
Another therapeutic technique involves laser photocoagulation of the venous malformation. Several laser wavelengths have been reported for the treatment of
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vascular malformations. The carbon dioxide (CO,) laser (wavelength - 10 600 nm) is absorbed by tissues with a high water content, resulting in cell vaporization [l]. The CO, laser has been used to treat vascular mucosal lesions of the oral cavity, with coagulation of capillary-sized blood vessels [15]. The argon laser (wavelength - 488-515 nm) penetrates skin or mucosal surfaces, and is useful in the treatment of port-wine stains or superficial telangiectasias [5]. The Nd:YAG laser (wavelength - 1060 nm) has deep soft tissue penetration (up to 1 cm) and scatter, creating deep photocoagulation of vessels up to 7 mm in diameter [15]. The Nd:YAG wavelength is absorbed best by hemoglobin and dark pigmented tissues, making it an obvious choice in the treatment of lowflow venous malformations. Several authors report good results with the Nd:YAG laser in the treatment of oral cavity and airway venous malformations [5,13,15]. The laser is set at low power (20 W), with intermittent energy exposure. Complications of Nd:YAG laser photocoagulation include edema, mucosal sloughing and fibrosis. Significant airway edema may result after laser treatment of a venous malformation; intubation or tracheotomy should be considered on an individual basis. 4.6. Treatment
response
The goal of treatment of an airway venous malformation is to stabilize the airway, while preserving normal anatomy. Treatment response is based upon clinical and radiographic findings. Regression of the lesion may be documented on physical examination, endoscopy or MRI scan. Airway status can be assessed in several ways; exercise tolerance, stridor or apnea are noted. In the patient with a tracheotomy, decannulation may be the therapeutic goal. Long-term follow-up is essential because of the natural history of venous malformations. Successful therapy results in long-term control of the malformation and the airway. Isolated case reports and small series exist in the literature, and treatment results vary [1,4,6,11- 13,15,17]. Obviously, choice of therapeutic modality and treatment results will depend on the size of the venous malformation and its location. A localized venous malformation of the tongue may regress after photocoagulation, sclerotherapy or surgical excision. A large, diffuse malformation involving the upper airway is more difficult. An individual treatment plan for such a lesion may require multiple sessions of sclerotherapy combined with laser photocoagulation. The patients in our series represent a spectrum of disease. One patient had mild airway and feeding difficulties that improved with growth and development. One young boy with a localized buccal venous malformation was treated successfully with a single injection. The other six patients had more extensive airway lesions with persistent symptoms of obstruction, All six underwent multiple sclerotherapy procedures; four of these patients required tracheotomy for airway control. Laser photocoagulation was performed in three patients; two also underwent surgical excision. Further treatment is planned for five of the eight patients. Large airway venous malformations should be approached in a careful, staged fashion to avoid tissue necrosis and scar formation. A combination of therapeutic modalities may be
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required to achieve a successful result. The combination of sclerotherapy and Nd:YAG laser photocoagulation appears to cause gradual regression of the malformation. Long-term follow-up is essential to assess overall treatment success. The treatment modalities discussed here - surgical excision, sclerotherapy and laser photocoagulation - may remove the lesion or cause thrombosis and regression of the malformation, but none alter the underlying vascular pathology [5]. The defect in vessel structure that created the venous malformation remains unchanged. The malformation persists as a dilated, ectatic venous structure that has normal endothelium, but lacks smooth muscle. Rather than thrombosing the dilated vessel, a more direct treatment approach would be to correct the smooth muscle defect. Some have suggested injecting a mitogenic agent directly into the malformation to stimulate smooth muscle proliferation (Folkman J, personal communication, 1995). Such a maneuver might create a stronger mural structure, with subsequent resolution of the malformation. Further study in this area may lead to a more sophisticated approach to the treatment of venous malformations. References [l] Apfelberg, D.B., Maser, M.R., Lash, H. and White, D.N. (1984) Benefits of the CO2 laser in oral hemangioma excision. Plast. Reconstr. Surg. 75, 46-50. [2] Burrows, P.E. and Fellows, K.E. (1995) Techniques for management of pediatric vascular anomalies. In: Cope, C. (Ed.), Current Techniques in Interventional Radiology, Current Medicine, Philadelphia, pp. 12-27. [3] Burrows, P.E., Mulliken, J.B., Fellows, K.E. and Strand, R.D. (1983) Childhood hemangiomas and vascular malformations: angiographic differentiation. Am. J. Radiol. 141, 483-488. [4] delorimier, A.A. (1995) Sclerotherapy for venous malformations. J. Pediatr. Surg. 30, 188-194. [5] Dixon, J.A., Davis, R.K. and Gilbertson, J.J. (1986) Laser photocoagulation of vascular malformations of the tongue. Laryngoscope 96, 537-541. [6] Fradis, M., Podoshin, L., Simon, J., Lazarov, N., Shagrawi, I. and Boss, J.H. (1989) Combined treatment of large head and neck capillaro-venous malformation by a fibrosing agent. J. Laryngol. Otol. 103, 390-398. [7] Kaban, L.B. and Mulliken, J.B. (1986) Vascular anomalies of the maxillofacial region. J. Oral Maxillofac. Surg. 44, 203-213. [8] Meyer, J.S., Hoffer, F.A., Barnes, P.D. and Mulliken, J.B. (1991) Biological classification of soft-tissue vascular anomalies: MR correlation. Am. J. Radiol. 157, 559-564. [9] Mulliken, J.B. and Young, A.E. (1988) Vascular birthmarks, hemangiomas and malformations. WB Saunders, Philadelphia. [lo] Mulliken, J.B. and Glowacki, J. (1982) Hemangiomas and vascular malformations in infants and children: a classification based on endothelial characteristics. Plast. Reconstr. Surg. 69, 412-420. [ll] Persky, M.S. (1986) Congenital vascular lesions of the head and neck. Laryngoscope 96, 10021015. [12] Persky, M.S., Berenstein, A. and Cohen, N.L. (1984) Combined treatment of head and neck vascular masses with pre-operative embolization. Laryngoscope 94, 20-27. [13] Rebeiz, E., April, M.M., Bohigian, R.K. and Shapshay, S.M. (1991) Nd-YAG laser treatment of venous malformations of the head and neck: an update. Otolaryngol. Head Neck Surg. 105, 6555661.
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[14] Roberts, J.T., Pile-Spellman, J., Joseph, M., Glinski, E., Chin, J. and Hacein-Bey, L. (1991) A patient with massive oral-facial venous malformation. J. Clin. Anesth. 3, 76-79. [15] Shapshay, S.M., David, L.M. and Zeitels, S. (1984) Neodymium-YAG laser photocoagulation of hemangiomas of the head and neck. Laryngoscope 97, 323-330. [16] Teitelbaum, G.P., Halbach, V.V., Fraser, K.W. et al. (1994) Direct-puncture coil embolization of maxillofacial high-flow vascular malformations. Laryngoscope 104, 1397-1400. [17] Woods, J.E. (1987) Extended use of sodium tetradecyl sulfate in treatment of hemangiomas and other related conditions. Plast. Reconstr. Surg. 79, 542-549. [18] Yakes, W.F., Luethke, J.M., Parker, S.H. et al. (1990) Ethanol embolization of vascular malformations. Radiographics 10, 7877796.
JOURNAL
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International Journal of Pediatric Otorhinolaryngology
ELSEVIER
37 (1996)
Venous malformation Laurie A. Ohlm+*,
99-114
of the pediatric airway’
James Forsen”, Patricia E. Burrowsb
“Department of Otolaryngology, Children’s Hospital, Harvard Medical School, Boston MA, USA bDepartment qf Radiology, Children 5 Hospital, Harvard Medical School, Boston MA, USA Received 29 February 1996; revised 29 April 1996; accepted 1 May 1996
Abstract Objective: To evaluate the management of venous malformations of the pediatric airway, including diagnostic criteria and response to sclerotherapy and laser photocoagulation. Design: Case series analysis of eight patients diagnosed with venous malformations of the upper airway. Setting: Academic, tertiary care, children’s hospital. Patients: Eight patients (3 female, 5 male) with congenital venous malformations of the upper airway. Intervention: Each patient underwent an individualized treatment regimen of sclerotherapy, laser photocoagulation and/or surgery. Results: The combination of sclerotherdpy and laser photocoagulation appears to cause gradual regression of the malformation. Five of the eight patients will require further therapy; two patients remain tracheotomy dependent. Conclusions: Extensive venous malformations of the pediatric airway require staged therapy, with a combination of sclerotherapy and photocoagulation. Long-term follow-up is essential because of the natural history of these lesions. Keywords:
Airway;
Pediatric;
Venous malformation
* Corresponding author, Department of Otolaryngology, Texas Children’s Hospital, 6621 Fannin St., Houston, TX 77030, USA. Tel.: + 1 713 770 3268; fax: + 1 713 770 3251. ’ Presented at the American Society of Pediatric Otolaryngology, Durango, Colorado, 28 May 1995. 01655876/96/$15.00 8 1996 Elsevier Science Ireland Ltd. All rights reserved PII SO165-5876(96)01382-l
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1. Introduction Vascular birthmarks are common in the head and neck. Most cause no interference with cosmesis or function and require no treatment. Other vascular lesions are larger and create significant problems, depending on location and size. Confusing terminology exists in the literature to describe these vascular anomalies in children. In 1982, Mulliken and Glowacki detailed a classification based upon clinical behavior and endothelial cell characteristics. Their system will be used in this paper to distinguish between the two main classes of vascular lesions, hemangiomas and vascular malformations [lo]. A vascular malformation is a collection of abnormal vessels forming a lesion that is present at birth and grows with the child. The malformation may be classified as capillary, venous, arterial or lymphatic. Combined channel anomalies are common, such as the arterio-venous malformation. Capillary, venous and lymphatic malformations are low-flow lesions, while the arterio-venous malformation is a high-flow entity. The malformation may enlarge by expansion of existing vessels, after trauma or hormonal changes; spontaneous resolution does not occur. There is no sexual predilection. In contrast, a hemangioma is a vascular tumor that enlarges by rapid endothelial cell proliferation. The hemangioma is usually not present at birth, but grows rapidly during the first year of life. The proliferative phase is followed by slow involution over the next 5-7 years. Females are more commonly affected than males. This report will focus on venous malformations of the pediatric airway. Although rare, these lesions may cause significant airway obstruction and thus require careful evaluation and treatment.
2. Materials
and methods
2.1. Technique All sclerotherapy procedures were performed in the radiology suite, under the direction of a pediatric interventional radiologist. All patients received general anesthesia, via either an endotracheal or tracheotomy tube. Cutaneous venous malformations were prepared in a sterile fashion for percutaneous injection. Airway malformations were visualized using a mouthgag or direct laryngoscopy when necessary. Direct puncture into the venous malformation was performed with a Teflon-sheathed needle (Angiocath 20-gauge, 2 inch; Becton Dickinson Vascular Access, Sandy, UT) and free flow of blood was obtained. Radiographic contrast material was then injected and the lesion was visualized with digital-subtraction serial imaging. The sclerosing agent was injected while occluding venous outflow. Sclerosing agents included 100% ethanol and 3% sodium tetradecyl sulfate (STS). The amount of agent injected was based upon the size and location of the malformation and the patient’s weight. The maximum dose of ethanol injected per
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sclerotherapy session was 1 ml/kg body weight; STS was injected to a maximum of 10 ml/session. Patients without a tracheotomy remained intubated until resolution of airway edema. All patients received dexamethasone and intravenous hydration for 24-48 h post-sclerotherapy. The neodymium yttrium aluminum garnet (Nd:YAG) laser was used to photocoagulate airway venous malformations in three patients in this series, following the technique described by Rebeiz et al. [13]. Direct laryngoscopy and the fiberoptic delivery system allowed treatment of upper airway malformations. The Nd:YAG laser was used at a power setting of 20 to 30 W, with a 0.5-1.0 s pulse duration. All procedures were performed under general anesthesia; two patients had a tracheotomy tube in place.
3. Case reports 3.1. Case # 1
This 9-year-old girl presented with a large cervical and mediastinal mass. The lesion was first noted at the age of 2 years, when a diagnosis of hemangioma was made. She was treated with steroids, with no change in the lesion. At the age of 7 years, the lesion suddenly increased in size. She developed increased shortness of breath with exertion that limited physical activity and had to sleep on several pillows. Physical examination revealed a large mass in the anterior left neck and supraclavicular areas. The mass was easily compressible and distended with a Valsalva maneuver. She had biphasic stridor in the supine position Magnetic resonance imaging (MRI) confirmed a venous malformation extending anterior and posterior to the trachea in the neck and mediastinum. The lesion surrounded the carotid, vertebral and subclavian arteries and pushed the trachea to the right (Fig. 1). Initial sclerotherapy of the anterior neck and supraclavicular region was carried out percutaneously, to place platinum coils and inject ethanol and STS. She remained intubated for several days until resolution of airway edema. Post-extubation, a mild left Horner’s syndrome and left vocal cord paresis were noted. MRI scan demonstrated thrombosis of the anterior and supraclavicular malformation, with residual lesion in the posterior mediastinum. Two months later, the remaining mediastinal malformation was treated, with placement of platinum coils and injection of ethanol. Post-treatment, a left phrenic nerve palsy was noted; hemoglobinuria resolved with hydration. Follow-up fluoroscopy 2 days later showed bilateral diaphragmatic movement. Repeat ethanol and STS injection was performed 4 months later. At last follow-up, the patient notes decreased shortness- of breath and increased activity level. 3.2. Case # 2
This 22-month-old
girl developed obstructive
sleep apnea early in life. Physical,
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examination revealed venous malformation involving the left cervicofacial region, oral cavity, anterior tongue and the base of tongue. Endoscopy demonstrated venous malformation of supraglottis (Fig. 2). The true vocal cords and trachea were clear. MRI scan confirmed the presence of a large cervicofacial venous malformation with upper airway obstruction (Fig. 3). Staged therapy was planned. Management began with oral intubation, followed by sclerotherapy. Intralesional injection of the anterior cervical malformation was performed using ethanol; the lower lip was injected with STS. Platinum microcoils were also placed in the left cervical malformation. Moder-
Fig. 1. (Patient artery (arrow).
1) Extensive
cervical
and mediastinal
venous
malformation,
surrounding
the carotid
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(arrow).
ate airway edema was observed; she was extubated 2 days later. Two months later, the midline cervical malformation had thrombosed and regressed significantly. Endoscopy revealed no change in the supraglottic lesion. Tracheotomy was performed, in preparation for further therapy. Using direct laryngoscopy for exposure, the soft palate, floor of mouth, base of tongue and left supraglottis were treated with ethanol. Three days later, the lower lip and anterior tongue were injected with ethanol. Five months later, she returned for repeat treatment. Direct laryngoscopy showed slight regression of the supraglottic venous malformation. The left supraglottis and left posterior pharynx were injected with ethanol. Three months later, tonsillectomy and adenoidectomy were performed, followed by injection of the supraglottis, anterior tongue, lower lip and submental region. Two sessions of Nd:YAG laser photocoagulation followed. The supraglottic malformation has regressed and she has been successfully decannulated. 3.3. Case # 3
This male infant was the product of a 31-week gestation, and demonstrated inspiratory stridor and difficulty feeding shortly after birth. Physicals examination revealed vascular lesions involving the right cervicofacial region, bropharupper back, penis and right lower ,extremity. Direct ynx, hypopharynx, laryngoscopy and bronchoscopy demonstrated vascular lesions of the anterior and base of tongue, lateral pharyngeal walls and soft palate. The epiglottis,
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true vocal cords and trachea were normal. MRI scan confirmed the presence of an enhancing lesion in the right cervicofacial region, with mediastinal extension (Fig. 4). The lesions were initially diagnosed as hemangiomas, and the patient received interferon cl-2a. His airway remained stable, but the lesions continued to slowly grow. After 8 months on interferon, the medication was discontinued. Biopsy of a right postauricular vascular lesion revealed venous malformation. Conservative management continued; the patient remained stable. He has some mild developmental delay, but at last follow-up (age 3.5 years) he has no respiratory or feeding problems.
3.4. Case # 4 This 4-year-old boy had a right cervicofacial and upper airway venous malformation, present since birth. After two intralesional injections, he had persistent obstructive sleep apnea. Physical examination showed venous malformation of the right face, soft palate, base of tongue and right lateral pharyngeal wall.
Fig. 3. (Patient 2) MRI demonstrates extensive left cervicofacial venous malformation.
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Fig. 4. (Patient 3) MRI scan of right cervicofacial venous malformation
(arrow).
MRI confirmed a large venous malformation with extension into the nasopharynx, floor of mouth and base of tongue (Fig. 5). A tracheotomy was performed, and he is now undergoing further sclerotherapy. 3.5. Case # 5
This 21-year-old female had undergone multiple previous treatments for an extensive left cervicofacial venous malformation, present since birth. Airway involvement included the floor of mouth, tongue, soft palate, nasopharynx and supraglottis. Prior treatment included surgical resection, sclerotherapy and tracheotomy. She was decannulated 1 year prior to referral to our institution; upon referral, she noted increasing shortness of breath. Examination and MRI scan revealed residual left cervicofacial venous malformation (Fig. 6). Flexible laryngoscopy demonstrated malformation at the base of the tongue and supraglottis, obstructing the larynx (Fig. 7). A long-standing left vocal cord paresis
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was documented. Because of increasing respiratory obstruction, a revision tracheotomy was performed. Three months later, sclerotherapy was performed using ethanol to inject the tongue, palate, left lateral pharyngeal wall and left face. Post-treatment she developed transient hemoglobinuria that resolved with hydration. Repeat ethanol injections of the oral cavity and supraglottic venous malformations were performed twice over the next 6 months. Staged surgical resection followed. Maxillary and mandibular osteotomies were performed, followed by partial excision of the malformation in the left cheek and tongue. Two months after surgery, the Nd:YAG laser was used to photocoagulate the supraglottic malformation. Three laser sessions have been performed thus far, with gradual regression of the lesion. Serial laryngoscopy with laser photocoagulation is planned over the next several months. Her tracheotomy remains in place.
Fig. 5. (Patient 4) MRI demonstrates right cervicofacial and nasopharyngeal venous malformation.
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Fig. 6. (Patient 5) MRI scan of left facial and upper airway venous malformation.
3.6. Case # 6
This 26-year-old male was diagnosed at the age of 2 years with a venous malformation extending from the right nasopharynx to the upper chest. The majority of the lesion .involved the right neck and he had undergone two prior surgical debulkings. He presented with a recent complaint of snoring and upper airway obstruction while sleeping. Physical examination, including flexible fiberoptic endoscopy, revealed an exophytic lesion involving the soft palate, right tonsillar region, right pharynx and right aryepiglottic fold. There was a large compressible mass involving the right lateral and anterior cervical regions with extension to the right chest wall. MRI revealed venous malformation anterior to the trachea, with tracheal deviation to the left. Direct laryngoscopy and bronchoscopy revealed engorgement of the lesion with the patient supine such that it nearly reached the midline of the oropharynx and hypopharynx. There was also mucosal involvement of the proximal one-third of the trachea. A polysomnogram documented moderately severe obstructive sleep apnea. The patient refused CPAP and standard tracheotomy was undesirable because of the location of the malformation.
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The patient underwent transoral injection of ethanol and STS to the right hypopharynx, oropharynx and soft palate. The cervical lesion was injected percutaneously. He remained intubated for 2 days and was extubated without difficulty. Two months post-operatively, the patient and his wife noted a much improved airway and sleep pattern, without snoring or apnea. He demonstrated mild hoarseness; laryngoscopy showed an immobile right true vocal cord in the paramedian position. Intraorally, the lesion was dramatically decreased in size. Six months post-operatively, he developed recurrent snoring, without apnea. A repeat sleep study revealed mild obstructive apnea. Further treatment is being considered. 3.7. Case # 7
This 34-year-old male had a large venous malformation involving the left face and neck, present since birth. Beginning at age 29 years, he underwent a series of fifteen sclerotherapy injections at an outside institution. A tracheotomy was placed prior to the first injection; he was decannulated several weeks later. The patient presented to our institution with a primary complaint of chronic throat and tongue pain. He also noted intermittent upper airway obstruction, especially at night. Examination revealed a large, bulky malformation involving the left face and neck, left tongue, uvula, left palate, left pharynx and laryngeal surface of the epiglottis.
Fig. 7. (Patient epiglottis (open
5) Endoscopic arrow).
view
of supraglottic
venous
malformation
(solid
arrow),
distorting
the
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He underwent two sclerotherapy injections with ethanol and STS, along with laser resection of the uvula. He remained intubated for 3 days after each treatment. After therapy, he reported general improvement in his pain and resolution of airway obstruction. He did suffer a full-thickness lower lip ulcer after ethanol injection which was treated conservatively with dressing changes. 3.8. Case # 8
This 23-month-old male presented with a 2 month history of increasing fullness in the right buccal region, without airway or feeding difficulty. Examination showed a soft, compressible mass in the buccal space. Computed tomography (CT) and MRI scans revealed a large, well-circumscribed enhancing lesion of the right masticator space. Transoral biopsy confirmed the diagnosis of venous malformation. He underwent percutaneous injection with ethanol and STS. Two months later, marked reduction in size of the mass was noted, with no residual facial asymmetry.
4. Discussion The venous malformation is a member of the family of vascular malformations. Usually a single vessel type predominates - lymphatic, capillary, venous or arterio-venous. The venous malformation is a slow-flow lesion that is present at birth and grows commensurately with the child. On physical examination, the venous malformation is a soft, compressible, non-pulsatile mass that expands with a Valsalva maneuver. Mucosal or airway lesions may demonstrate purplish discoloration and lie adjacent to normal airway structures. Rapid enlargement may occur after trauma (injury, surgery) or with hormonal changes (puberty, pregnancy). Phlebothrombosis is common and may be associated with recurrent localized pain [91.
Most venous malformations can be diagnosed after a careful history and physical examination. A venous malformation must be distinguished from another common pediatric vascular lesion, the hemangioma, which has a very different clinical course and requires other forms of treatment. In contrast to the hemangioma, the venous malformation is present at birth and will grow with the child. Spontaneous resolution is virtually non-existent. Histologic examination reveals dilated or ectatic vascular channels lined by normal endothelium; the venous malformation enlarges as these abnormal vessels undergo progressive dilatation. 4.1. Radiographic
evaluation
Radiographic studies provide further diagnostic information and are an integral part of treatment. Plain films may demonstrate the phleboliths that are commonly found in venous malformations. Secondary bony distortion may also be seen, with change in shape and increase in size of the underlying skeletal structures [7].
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Ultrasound is a simple, non-invasive modality that can identify the venous malformation as a slow-flow lesion. CT has been used in the past to delineate the extent of the lesion and map its relationship to surrounding structures. More recently, the MRI scan has added valuable information, With the use of intravenous contrast (gadolinium) and T2-weighted sequences, the radiologist can distinguish vascular malformation subtypes [2,8]. MRI evaluation of a venous malformation will demonstrate abnormal vessels of varying caliber, without intervening parenchyma. Angiography can also demonstrate the extent of vascular involvement, identify the feeding and draining vessels and document treatment response. The venous malformation is characterized by ectatic, dilated vascular spaces that fill in the venous phase and demonstrate prolonged pooling of contrast material. The malformation is a diffuse lesion consisting entirely of abnormal vessels without intervening tissue stain [3]. 4.2. Treatment Many venous malformations of the head and neck are small and asymptomatic. Supportive care and reassurance may be adequate, along with education about the natural history of these lesions. The patients should be counseled to avoid trauma and be prepared for possible hormonal changes. Other venous malformations, such as those described in this series, are much larger and cause significant airway obstruction. Lesions that impair function (airway obstruction, pain, bleeding, infection, serious cosmetic deformity) require more aggressive therapy. The goal of treatment for these malformations should be control of symptoms with conservation of normal tissues whenever possible [5]. A variety of treatment modalities have been tried throughout the years, with varying results. These include irradiation, electrocoagulation, cryotherapy, corticosteroids and compression techniques. Well-localized venous malformations may be suitable for surgical excision [l 1,121. However, resection of larger lesions is usually associated with significant blood loss and morbidity. In some cases, the venous malformation may be treated pre-operatively to decrease the size or vascularity prior to resection. Other malformations are not amenable to excision because of size and location. In these instances, alternative therapy is required. 4.3. Sclerotherapy Sclerotherapy has long been used to treat vascular lesions. This technique involves direct injection of a sclerosing solution into the center of the venous malformation, while occluding both the arterial inflow and venous outflow [9]. Many agents have been injected into venous malformations in an attempt to generate thrombosis and lead to a decrease in size and vascularity [4]. The assistance of a skilled interventional radiologist is essential. The sclerosing agent causes an intense inflammatory reaction, induces thrombosis and subsequently leads to fibrosis of the malformation [14]. Progressive fibrosis is expected to continue for 2-3 months.
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Sclerosing agents currently in use in the US include STS and absolute ethanol. STS is a synthetic anionic detergent that was originally used to treat varicose veins in the extremities [17]. Ethanol is a low viscosity agent useful for localized thrombosis. Choice of a particular sclerosing agent is based upon the location of the lesion. Ethanol is a cytotoxic agent that necroses endothelial cells quickly, and is often chosen to treat large, deep venous malformations. STS is a slightly milder agent and is used to treat more superficial malformations to decrease the risk of skin necrosis [14]. Multiple injections may be required, depending on the treatment response. If indicated, sclerosed venous malformations can be excised lo- 14 days after injection. The inflammatory response associated with sclerotherapy is intense, and significant airway edema results, resolving over 24448 h. It is crucial to protect the airway in such cases. Prolonged intubation is appropriate for some patients, while tracheotomy may be indicated for the patient who will require multiple sclerosing procedures. Sclerotherapy results in hemolysis of red blood cells within the venous malformation, with subsequent hemoglobinuria in 50% of children [2,4]. To prevent renal toxicity, intravenous fluids are administered at twice normal rates during the procedure and the recovery period [2]. Complications of sclerotherapy may occur if the sclerosing agent passes into the normal adjacent vasculature. Absolute ethanol is a potent intravascular embolic agent that can cause neuropathy and tissue necrosis [4]. Three of our patients developed post-injection nerve paresis. One (patient # 5) had long-term left vocal cord paralysis after multiple surgical and sclerotherapy procedures. Another patient ( # 6) developed ipsilateral vocal cord paralysis after transoral and percutaneous injections. The other patient ( # 1) developed a transient left phrenic nerve palsy that resolved over several days and a left true vocal cord paresis. One patient ( # 7) sustained a lip ulcer after ethanol injection that resolved with conservative therapy; none of our patients experienced permanent skin necrosis. The inflammatory response after sclerotherapy may also lead to fibrosis and scar formation. Sclerotherapy should be performed very carefully in delicate areas like the larynx. Controlled injection is essential, with superselective catheter techniques or direct percutaneous embolization [18]. 4.4. Embolization
An adjunct to sclerotherapy is the placement of intravascular embolization coils. These coils have a high thrombogenicity and create long-term vascular blockage in selected lesions. Choice of the type of coil may depend on plans for follow-up radiographic imaging. Steel and platinum coils cause significant imaging artifact on CT scans. Steel, which is ferromagnetic, also creates an artifact on MRI. Platinum is non-ferromagnetic and causes fewer problems on MRI scan; platinum coils should be used when follow-up MRI scans are anticipated [16]. 4.5. Laser therapy
Another therapeutic technique involves laser photocoagulation of the venous malformation. Several laser wavelengths have been reported for the treatment of
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vascular malformations. The carbon dioxide (CO,) laser (wavelength - 10 600 nm) is absorbed by tissues with a high water content, resulting in cell vaporization [l]. The CO, laser has been used to treat vascular mucosal lesions of the oral cavity, with coagulation of capillary-sized blood vessels [15]. The argon laser (wavelength - 488-515 nm) penetrates skin or mucosal surfaces, and is useful in the treatment of port-wine stains or superficial telangiectasias [5]. The Nd:YAG laser (wavelength - 1060 nm) has deep soft tissue penetration (up to 1 cm) and scatter, creating deep photocoagulation of vessels up to 7 mm in diameter [15]. The Nd:YAG wavelength is absorbed best by hemoglobin and dark pigmented tissues, making it an obvious choice in the treatment of lowflow venous malformations. Several authors report good results with the Nd:YAG laser in the treatment of oral cavity and airway venous malformations [5,13,15]. The laser is set at low power (20 W), with intermittent energy exposure. Complications of Nd:YAG laser photocoagulation include edema, mucosal sloughing and fibrosis. Significant airway edema may result after laser treatment of a venous malformation; intubation or tracheotomy should be considered on an individual basis. 4.6. Treatment
response
The goal of treatment of an airway venous malformation is to stabilize the airway, while preserving normal anatomy. Treatment response is based upon clinical and radiographic findings. Regression of the lesion may be documented on physical examination, endoscopy or MRI scan. Airway status can be assessed in several ways; exercise tolerance, stridor or apnea are noted. In the patient with a tracheotomy, decannulation may be the therapeutic goal. Long-term follow-up is essential because of the natural history of venous malformations. Successful therapy results in long-term control of the malformation and the airway. Isolated case reports and small series exist in the literature, and treatment results vary [1,4,6,11- 13,15,17]. Obviously, choice of therapeutic modality and treatment results will depend on the size of the venous malformation and its location. A localized venous malformation of the tongue may regress after photocoagulation, sclerotherapy or surgical excision. A large, diffuse malformation involving the upper airway is more difficult. An individual treatment plan for such a lesion may require multiple sessions of sclerotherapy combined with laser photocoagulation. The patients in our series represent a spectrum of disease. One patient had mild airway and feeding difficulties that improved with growth and development. One young boy with a localized buccal venous malformation was treated successfully with a single injection. The other six patients had more extensive airway lesions with persistent symptoms of obstruction, All six underwent multiple sclerotherapy procedures; four of these patients required tracheotomy for airway control. Laser photocoagulation was performed in three patients; two also underwent surgical excision. Further treatment is planned for five of the eight patients. Large airway venous malformations should be approached in a careful, staged fashion to avoid tissue necrosis and scar formation. A combination of therapeutic modalities may be
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required to achieve a successful result. The combination of sclerotherapy and Nd:YAG laser photocoagulation appears to cause gradual regression of the malformation. Long-term follow-up is essential to assess overall treatment success. The treatment modalities discussed here - surgical excision, sclerotherapy and laser photocoagulation - may remove the lesion or cause thrombosis and regression of the malformation, but none alter the underlying vascular pathology [5]. The defect in vessel structure that created the venous malformation remains unchanged. The malformation persists as a dilated, ectatic venous structure that has normal endothelium, but lacks smooth muscle. Rather than thrombosing the dilated vessel, a more direct treatment approach would be to correct the smooth muscle defect. Some have suggested injecting a mitogenic agent directly into the malformation to stimulate smooth muscle proliferation (Folkman J, personal communication, 1995). Such a maneuver might create a stronger mural structure, with subsequent resolution of the malformation. Further study in this area may lead to a more sophisticated approach to the treatment of venous malformations. References [l] Apfelberg, D.B., Maser, M.R., Lash, H. and White, D.N. (1984) Benefits of the CO2 laser in oral hemangioma excision. Plast. Reconstr. Surg. 75, 46-50. [2] Burrows, P.E. and Fellows, K.E. (1995) Techniques for management of pediatric vascular anomalies. In: Cope, C. (Ed.), Current Techniques in Interventional Radiology, Current Medicine, Philadelphia, pp. 12-27. [3] Burrows, P.E., Mulliken, J.B., Fellows, K.E. and Strand, R.D. (1983) Childhood hemangiomas and vascular malformations: angiographic differentiation. Am. J. Radiol. 141, 483-488. [4] delorimier, A.A. (1995) Sclerotherapy for venous malformations. J. Pediatr. Surg. 30, 188-194. [5] Dixon, J.A., Davis, R.K. and Gilbertson, J.J. (1986) Laser photocoagulation of vascular malformations of the tongue. Laryngoscope 96, 537-541. [6] Fradis, M., Podoshin, L., Simon, J., Lazarov, N., Shagrawi, I. and Boss, J.H. (1989) Combined treatment of large head and neck capillaro-venous malformation by a fibrosing agent. J. Laryngol. Otol. 103, 390-398. [7] Kaban, L.B. and Mulliken, J.B. (1986) Vascular anomalies of the maxillofacial region. J. Oral Maxillofac. Surg. 44, 203-213. [8] Meyer, J.S., Hoffer, F.A., Barnes, P.D. and Mulliken, J.B. (1991) Biological classification of soft-tissue vascular anomalies: MR correlation. Am. J. Radiol. 157, 559-564. [9] Mulliken, J.B. and Young, A.E. (1988) Vascular birthmarks, hemangiomas and malformations. WB Saunders, Philadelphia. [lo] Mulliken, J.B. and Glowacki, J. (1982) Hemangiomas and vascular malformations in infants and children: a classification based on endothelial characteristics. Plast. Reconstr. Surg. 69, 412-420. [ll] Persky, M.S. (1986) Congenital vascular lesions of the head and neck. Laryngoscope 96, 10021015. [12] Persky, M.S., Berenstein, A. and Cohen, N.L. (1984) Combined treatment of head and neck vascular masses with pre-operative embolization. Laryngoscope 94, 20-27. [13] Rebeiz, E., April, M.M., Bohigian, R.K. and Shapshay, S.M. (1991) Nd-YAG laser treatment of venous malformations of the head and neck: an update. Otolaryngol. Head Neck Surg. 105, 6555661.
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[14] Roberts, J.T., Pile-Spellman, J., Joseph, M., Glinski, E., Chin, J. and Hacein-Bey, L. (1991) A patient with massive oral-facial venous malformation. J. Clin. Anesth. 3, 76-79. [15] Shapshay, S.M., David, L.M. and Zeitels, S. (1984) Neodymium-YAG laser photocoagulation of hemangiomas of the head and neck. Laryngoscope 97, 323-330. [16] Teitelbaum, G.P., Halbach, V.V., Fraser, K.W. et al. (1994) Direct-puncture coil embolization of maxillofacial high-flow vascular malformations. Laryngoscope 104, 1397-1400. [17] Woods, J.E. (1987) Extended use of sodium tetradecyl sulfate in treatment of hemangiomas and other related conditions. Plast. Reconstr. Surg. 79, 542-549. [18] Yakes, W.F., Luethke, J.M., Parker, S.H. et al. (1990) Ethanol embolization of vascular malformations. Radiographics 10, 7877796.