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Handling the Forehead Donor — the Basics, Old Scars, Previous Forehead Flaps, Delay and Expansion
Handling the Forehead Donor — the Basics, Old Scars, Previous Forehead Flaps, Delay and Expansion
8
C H A P T E R
Treat the primary defect first. Do not let concern for the secondary defect endanger the final results. Sir Harold Gillies
It takes courage to harvest forehead skin from an already anxious and fearful patient. But the deformed face requires correction. Fortunately, knowledge, experience, and proper technique build confidence. The nose can be repaired with little injury to the donor site. The final result necessitates doing the ‘right thing’. Take whatever you need from the forehead to make the nose!
The Basics The size, vascularity and quality of forehead skin make it the first choice for major nasal repair. Its expansive surface is perfused from multiple arcades of axial vessels which enter along its periphery. The paramedian forehead flap design, based inferiorly on the supratrochlear vessels, seems best. It harvests skin high under the hairline — away from the central and most visibly important facial landmarks. Its narrow pedicle — 1.2 to 1.5 cm in width — allows primary closure of the inferior forehead, leaving a single-line scar above the brow, which is minimally intrusive. The eyebrow is not distorted or medialized on return of the proximal pedicle base to the eyebrow. The flap is elevated and transferred in two or three stages. At the time of transfer, the residual forehead is undermined bluntly in the subfrontalis plane over the periosteum, superiorly and laterally into each temple. Bleeding is modest and postoperative hematoma does not occur. Under moderate tension, several key tacking sutures are placed, exiting one to two millimeters from the wound edge. Although they remain for 10 days, because they are so close to the wound edge, a significant suture mark does not follow. Then a layered closure, using 4-0 and 5-0 permanent or slowly absorbing sutures, is performed to approximate the frontalis muscle and then the subcuticular skin, followed by 6-0 silk or plain gut suture for the skin. A superior dog-ear is excised within the scalp. If the forehead cannot be closed primarily, the gap remains superiorly positioned. It is allowed to heal secondarily. A petrolatum impregnated fine gauze is applied to cover the raw periosteum and fixed temporarily with 5-0 chromic suture. The patient can shampoo the following day and wash the nose and forehead. The impregnated gauze dressing is removed in 7 to 10 days. Healthy granulation tissue slowly fills the open gap. It is protected with a light nonadherent dressing, if desired. Daily washing
Chapter • 8 • The Basics, Old Scars, Previous Forehead Flaps, Delay and Expansion
continues. The wound fills with granulation tissue, contracts and spontaneously reepithelializes. Intraoperatively and postoperatively, the frontal periosteum should be protected from trauma and desiccation. But it will heal satisfactorily, even if large areas of periosteum are denuded and frontal bone exposed. Wait and let nature heal itself. Depending on elasticity of the tissue, the presence of old scars, or the harvesting of a past forehead flap, the donor site can often be closed primarily. This applies if the area that requires resurfacing is limited to the width of a single subunit — the ala, the ala and sidewall, the tip or the tip and dorsum. Note, however, the expanse of forehead required to resurface the convex tip or multiple units is frequently underestimated. In such cases, a gap may remain superiorly and should be allowed to heal secondarily. The open area may vary from a few millimeters to several centimeters. The adjacent normal forehead tissues stretch by autoexpansion. Frequently, a small gap heals spontaneously within 3 to 6 weeks. If desired, the resultant forehead scar can be excised, the wound edges undermined for 1 to 2 cm and the incision reclosed, in layers, at the time of pedicle division. Larger forehead defects heal spontaneously over 4 to 10 weeks. The gap granulates, re-epithelializes and contracts — an almost 4-cm defect may shrink to 1.5–2 cm. Although the scar will be red and raised for 2 to 6 months, it will not be depressed. The final forehead contour is excellent. Depending on scar quality, it can be excised and the adjacent forehead re-advanced in one to two stages, 4 to 6 months after pedicle division. In most cases, it can be completely excised or nearly completely excised during a late revision. Often, although present, the scar is unobtrusive and is not revised. In the typical repair, no revision is performed. The nose looks good and the forehead does not appear injured. In more difficult reconstructions, refining the reconstructed nose by sculpting the alar crease, recreating the nasolabial fold or thinning the nostril will be helpful. Revision of the forehead scar is easily combined with these procedures. Forehead scar revisions are primarily performed only in complex repairs which required a large flap. A forehead allowed to heal secondarily will always have a more aesthetic appearance than one closed with a skin graft or one distorted and denervated by extensive scalp or forehead advancements. If a gap remains in the superior forehead which cannot be closed, let it heal secondarily. Examination of the many cases illustrated in the text should put the surgeon at ease. When I ask myself the question — ‘Is the scar worth it?’ — my answer is always ‘yes!’ For example, this 14-year-old girl (Figure 8–1) underwent a three-stage forehead flap and support replacement to reconstruct her nose destroyed by an infantile hemangioma. A large flap was harvested to resurface the unit. The gap in the superior forehead was allowed to heal secondarily. Each week, the residual defect became smaller. At 8 weeks, prior to pedicle division, the wound was nearly healed. Months later, during a revision, the forehead scar was excised and the adjacent skin advanced and reapproximated. A small remaining gap was left to heal spontaneously.
Delay and Forehead Expansion Foreheads vary in height and width (which are determined by hairline position), laxity, the presence of scars, prior injury or past forehead flap harvest. 240
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Figure 8–1
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Figure 8–1, Continued
Practically speaking, when faced with a nasal defect, the surgeon must ask two questions: Is skin available to resurface the nose? Can it be transferred with a reliable blood supply? Perhaps reflecting a lack of confidence, surgeons become misdirected away from the important problems — recreating outline, symmetry, and contour. Often they look to unnecessary maneuvers or technology to lessen their anxiety. Most often, delay of the flap or expansion of the donor site is undertaken — not because it ‘should be’ but because it ‘can be’. Unless specifically indicated, neither method improves the final result of nasal repair. Both delay its completion and both add their own inherent disadvantages and risks of complications to an already complex situation. Do not waste time or energy on the forehead unless it will contribute to the final result. The forehead is a very forgiving donor site — expansive, highly vascular, self-healing and lending itself to secondary revision. Employ delay or expansion only when appropriate. Such cases are the exception. Nature blessed the reconstructive surgeon with the forehead to repair a nose. The fear of late forehead deformity is a misdirected priority. Ask yourself: Is this maneuver going to help build a better nose or will it divert attention away from the truly difficult aspects of repair? — taking bits and pieces of expendable tissue and recreating a facsimile that looks and breathes like a nose. 242
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Surgical delay Under most circumstances, delay of a forehead flap prior to transfer is neither helpful nor required. It is almost never needed when harvesting tissue from a previously uninjured and virgin forehead. In occasional cases, a surgical delay of the flap is employed, prior to transfer, to enlarge the available flap territory or to augment its blood supply and improve vascular safety. Consider surgical delay of a forehead flap when: 1. 2.
3.
4.
5. 6.
A significant old scar, which may interfere with its axial vessels, lies within the proposed flap territory. The pedicle’s named blood supply is suspect due to previous injury (prior trauma, history of a previous overly aggressive browlift, multiple past forehead flaps). Unusually complex extensions of flap design are required (very uncommon). The perfusion of a paramedian forehead flap is excellent especially if it has not been thinned. The flap design extends across one vascular territory into the territory of another flap. For example, the axial blood supply of the Sickle flap is based on the superficial temporal artery of the scalp. This scalp vessel collateralizes with the supraorbital and supratrochlear systems which are the primary blood supply to the lateral forehead. Surgical delay of a Sickle flap ensures the safe transfer of skin within the secondary forehead angiosome. Because the supratrochlear vessels reliably perfuse the forehead, high into the hairline, a paramedian flap of almost any size can be transferred without delay. The patient is an end stage smoker or has a history of radiation. During a complementary procedure, the surgeon is in doubt and a preliminary operation is required for other reasons (a prefabrication, a delay of lining hingeover flaps, etc.).
To delay a flap, the dimension and outline of the defect, which requires resurfacing, are determined. The template is positioned on the forehead donor site over the territory of the planned pedicle and marked with ink. This will routinely be the supratrochlear vessels. The proposed flap edges are incised to periosteum. In many cases, a few millimeters of the peripheral outline are left intact at the flap’s columellar and alar tips, to ensure that the flap can initially handle the intervention. These minor tissue connections may be transected in the office prior to formal flap transfer. Because all significant contributions to the forehead blood supply arise from peripheral axial vessels and not from the areolar connections to the underlying periosteum, the flap does not need to be elevated to stimulate the increased vascularization associated with surgical delay. The diffuse sources of blood supply, which normally contribute to the forehead survival, are eliminated, ‘training’ the flap to survive on a single source at the pedicle’s base. One month later, vessels at the base of the flap are enlarged. Overall vascularity is increased, the territory available for transfer is enlarged, and perfusion across an old scar supplemented, if needed. Always consider the many disadvantages of delay. 243
Chapter • 8 • The Basics, Old Scars, Previous Forehead Flaps, Delay and Expansion
1. 2.
3.
Additional stages, added cost, and prolongation of the overall reconstruction. The inability to alter flap dimensions at the time of transfer — length, width and border outline. Although it may be possible to create a template which will accurately define the recipient requirements, it is difficult to precisely determine the dimensions and outline of a forehead flap before recreating the defect, returning normal to normal and placing support grafts over reconstructed lining. Possible flap induration and loss of pliability. This should not be a significant problem as long as the flap itself is not undermined during the delay. It should be incised along its borders, but not elevated, during the preliminary operation to improve its blood supply.
For instance in this patient (Figure 8–2), significant facial scarring followed smallpox in infancy. During his teenage years, the cheeks were resurfaced with split-thickness skin grafts, and the nose with a left lateral horizontal forehead flap, pedicled on the superficial temporal artery. After pedicle division, the residual flap was returned to the forehead and the remaining right temple defect was skin grafted. When seen many years later, he desired improvement. Lengthy horizontal scars lay across the forehead both beneath the hairline and above the brow within the territory of a planned left paramedian forehead flap. Survival of the skin distal (superior) to two transverse scars was unlikely without surgical delay. Prior to nasal repair, the left supratrochlear vessels were identified and a full-thickness paramedian forehead flap was outlined. It was incised through the skin to the periosteum except for a few millimeters at the tip of the columella and both alar bases. Four weeks later, nasal lining was restored with hingeover flaps to lengthen the nose. Primary cartilage batten grafts were positioned to support the alae. The flap was elevated with all its layers and transferred without incident. Note that two transverse scars cross the flap’s territory. But the flap was well vascularized and healed without incident. The large gap in the forehead was allowed to heal primarily.
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Figure 8–2
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One month later, the first of two intermediate operations was performed (Figure 8–3). The defect extended from high on the radix to the nasal base. Total re-elevation and
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Figure 8–3
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Figure 8–3, Continued
debulking of frontalis muscle and subcutaneous fat over such a large area, crossed by full-thickness scars, would put the flap at risk. So initially, forehead skin with 2 to 3 mm of subcutaneous fat was re-elevated over the inferior two thirds of the nose. The transverse scar which crosses the proximal aspect of the flap is visible, crosshatched with ink. For vascular safety, the columella inset was not re-elevated. However, extensive subcutaneous sculpturing of excess frontalis and subcutaneous fat as well as placement of a delayed primary tip graft was performed. The flap was reapproximated to the recipient site with peripheral and quilting sutures. Despite profuse vascularity at the time of initial transfer to the nose 4 weeks before, the tip of the right ala became superficially ischemic, over several days. Fortunately this healed without significant incident, although the alar base became slightly malpositioned. Six weeks later, a second intermediate operation was performed to further sculpt the proximal dorsum and nasal root. The flap was re-elevated from the superior inset to expose the midnose and radix, the excess soft tissues excised and the flap returned to the sculpted recipient site. The forehead flap was divided one month later. Vascularity remained excellent during the later procedures. 247
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Seen, just 6 weeks later, in this early postoperative photograph (Figure 8–4), his nasal appearance is significantly improved. Despite the harvest of a horizontal flap with skin grafting of the donor site and a later paramedian forehead flap, with secondary healing of the second new donor gap, the appearance of the forehead has not been impaired.
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Scars within the Forehead
Significant scarring within the paramedian territory necessitated technique modification in this patient. To maintain maximal vascularity, the flap was delayed. A full-thickness forehead flap was employed to include all vascular layers. During the intermediate operation, the flap was re-elevated in stages, maintaining a partial distal inset to augment the blood supply coming from the brow. Interestingly, the flap tolerated initial transfer without incident. Superficial necrosis developed only during the first intermediate operation, suggesting this may have been a technical error due to too superficial re-elevation or tension on closure. Fortunately, the borderline vascularity of the right alar tip did not significantly limit the result.
Scars within the Forehead Determine the recipient requirements and outline the available surface area of the forehead. If a scar lies within the proposed flap territory the surgeon must determine the site, direction, depth, and length of the scar. A transverse scar puts the flap at greater risk. A review of old operative reports may clarify whether the injury extended only superficially, injuring only the random cutaneous blood supply, deeper through the galeal frontalis or directly to the vascular pedicle at the flap’s base. Doppler examination of the supratrochlear artery and its ascending vertical branches may confirm their presence or absence. If the vessels can be followed up the forehead, the surgeon can be reassured that they are intact. This would also apply if history suggests that the pedicle may have been injured by past injury or surgery.
Options when a scar lies within the flap territory 1.
2.
3. 4.
5.
6.
In many cases, it is possible to quickly determine that a visible scar is of little consequence. A scar can be disregarded if it is short, vertical, superficial, or the presence of flap’s named vessel can be verified by Doppler. The surgeon may avoid the scarred area entirely. The opposite contralateral pedicle can be used to transfer skin from the opposite side of the forehead, if it is adequate in size and vascularity. This has the disadvantage of increasing the distance to the defect and the need for a longer flap to reach the defect on the opposite side of the nose. The flap territory can be surgically delayed to augment its blood supply. This is useful when the surgeon has special concern. The flap can be elevated as a full-thickness flap to maintain its maximal blood supply. Under such circumstances, the full-thickness forehead flap is thinned later during the intermediate operation. It is re-elevated as a bipedicle extending from the brow to the columella and nostril rims. Because the flap remains well vascularized from both the proximal pedicle and distal inset during the second stage, the scar should be of significantly less concern because it lies within the middle of the flap’s surface. Even if the forehead is scarred, an area of virgin skin may be available to expand. An area of the forehead is transferred that avoids the area of concern. In rare instances when both supratrochlear arteries have been ablated and extensive scarring may exist within the inferior forehead, available forehead skin can be transferred on other vascular pedicles — e.g. use a scalping flap or sickle flap, rather than a paramedian flap based on the supratrochlear vessels. 249
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For example, this patient presented after a repair of an extensive midfacial nasal, canthal, and cheek defect (Figure 8–5). Bilateral cheek, eyelid, and scalp advancement and rotation flaps dragged the borders of the wound medially to close the holes. The nasal dorsum was flat and the tip pulled superiorly. A plan was outlined. A fullthickness release of her nasal tip would reposition it to its normal position. A septal composite flap would be pulled out of the pyriform aperture to restore a septal partition and provide lining. Multiple dorsal, sidewall and columellar rib cartilage grafts would support the repair and forehead skin would resurface the midvault and nasal sidewalls. Unfortunately the prior repair complicated future reconstruction. Both supratrochlear and supraorbital arteries had been transected. An oblique scar extended superiorly from the left medial brow into the right temple. Incisions lay within both upper lids, along the lower lids, and lateral to both nasolabial folds. However, skin was available in the left upper forehead and could be transferred based on superficial temporal vessels. This is the Sickle flap, as described by New.
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Scars within the Forehead
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Skin within the forehead receives its primary blood supply from the supratrochlear and supraorbital vessels and a secondary perfusion from the lateral scalp. During an initial operation (Figure 8–6), a forehead flap, based on the left superficial temporal and postauricular vessels, was delayed by incising its periphery. This skin was too valuable to risk and the superficial temporal vessels may not reliably perfuse this secondary angiosome without delay. At the same time, the residual normal tip was repositioned by incising the nose transversely into the nasal cavity. This reopened the significant full-thickness defect of the midvault. A composite septal flap was swung out of the nasal cavity to fix the position of the nasal tip. It also provided lining for the future nasal vault. At a later procedure, mucoperichondrium of the composite flap was hinged laterally bilaterally. Rib grafts were placed for dorsal, columellar, and sidewall support. And the Sickle flap was transferred to resurface the upper and middle nose. During an intermediate sculpting operation to improve the nasal contour, an expander was placed under the intact right forehead (Figure 8–7).
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Scars within the Forehead
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Figure 8–7
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After expansion, the forehead flap pedicle was divided and the residual flap was returned to the scalp. The expanded right forehead skin was elevated and pulled laterally to resurface the remaining donor defect within the left forehead. Postoperatively (Figure 8–8), a normal nasal contour has been re-established. The paramedian forehead flap should be the surgeon’s first choice. However, scars within its territory or injury to the supratrochlear vessels do not preclude the use of forehead skin, based on other named vessels. Historically, although more morbid, the Converse Scalping flap has been used most often.
The Technique of Forehead Flap Delay 1.
2.
A Figure 8–8
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Design a flap template with the required dimension, outline and length to supply the defect. Remember that it cannot be altered or extended at the time of transfer. Transfer the template to the donor site and mark with ink. Then stop and check the measurements a second time and reconfirm your requirements. Reconfirm adequate flap length, the position of the pivot point and flap reach. Mark twice or more and cut once.
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Expansion of the Forehead
3.
4. 5.
6.
Delay the flap, making peripheral incisions through the skin, subcutaneous tissues and frontalis down to the areolar layer over the frontal bone. Because little blood supply enters from the frontal bone, no undermining is required to stimulate vascularization of the flap by delay. Undermining causes unnecessary induration and edema and has no advantage. Frequently the entire border outline will be incised in one stage, leaving just a few millimeters of intact skin at the columella or alar tips. If the flap seems at greater risk, it may be delayed in one or two stages, leaving 4 mm bridges of intact skin along its peripheral border and at the tip and at each alar extension. These are incised at two week intervals until its border is completely incised. At transfer one month later, elevate the flap with all its layers as a full-thickness forehead flap. Thin the flap’s excess soft tissue during the intermediate operation to ensure vascular safety. Consider re-elevating the flap incompletely or in multiple stages. It can be re-elevated while maintaining a distal inset during the intermediate stage or, if the recipient site and its required flap is large and its vascularity in question, it can be debulked in stages during a second intermediate operation. Occasionally, in the tight and scarred forehead, both tissue expansion and delay are required to provide an adequate surface area for repair and to ensure vascularity. First, expansion is completed. Then the expanded skin is delayed, in stages. The required defect pattern is applied over the surface of the expander and border incisions are made through the skin, subcutaneous tissue and frontalis muscle to the underlying capsule. When performed using loupe magnification, the risk of injury to the underlying implant is real, but injury is avoidable. After incision of the skin with a scalpel, the underlying soft tissue can be safely divided with the blunt tip of a cautery. Frequently, the capsule space will be entered but this can occur without incident. The wound edges are reapproximated and a layered closure performed. The outline of the flap may be delayed in stages, if needed.
Expansion of the Forehead In special circumstances, pre-expansion of the forehead will improve the surgeon’s ability to reconstruct a nose. It can increase the amount of tissue available for transfer. In unusual circumstances, it is useful. However, it is rarely necessary. The surgeon must measure the dimension of the needed cover skin and compare it to the size of forehead available for nasal resurfacing. A ‘virgin’ forehead can supply enough skin to resurface any nasal defect. Most defects are relatively small. The forehead is easily closed primarily. When total nasal resurfacing is required, a gap may remain which cannot be closed. However, secondary healing heals the wound. Autoexpansion and contraction decrease the size of the late scar. A scar revision can be performed later, if desired. Occasionally, the donor site is limited by old scars or past harvest. In these unusual circumstances, pre-expansion can enlarge the excess available for nasal repair. It is not employed, however, to make closure of the forehead easier. Preliminary forehead expansion has many disadvantages. 255
Chapter • 8 • The Basics, Old Scars, Previous Forehead Flaps, Delay and Expansion
1. 2. 3. 4. 5. 6.
7.
8. 9.
It delays the nasal repair, increases the number of operative stages and adds additional expense. It necessitates multiple office visits and additional supplies. It subjects the patient to a lengthy period of social isolation due to its unusual, but temporary, deformity. It risks infection and extrusion. It causes frontal bone erosion and callus formation. Unexpected flap recoil may occur after transfer, if the stretched expanded skin is not rigidly braced with a hard tissue framework to maintain its proper dimension. It is difficult to outline the flap template on the globelike surface of the expander, especially where the expanded skin joins the normal adjacent unexpanded skin. An expander makes surgical delay of the flap more complicated. Expansion does not reliably improve the blood supply of the flap.
Forehead expansion should be considered: 1.
2.
In an especially tight forehead with limited available skin — one with extensive forehead scarring or prior forehead flap harvest. Expansion can increase the length and width of available skin by expanding any remaining useful skin territory. The surgeon may expand the proposed flap, prior to its transfer, or expand the residual forehead adjacent to a planned flap, using the expanded skin for secondary closure of the primary forehead defect. Very rarely, in an especially short forehead (less than 3–4 cm in height), pre-expansion can be used to increase flap length and minimize the amount of hair transferred to the nose.
However in most instances, expansion is not employed. The pedicle is simply incised, more inferiorly, across the brow. This lowers the pivot point and brings the base of the flap closer to the defect. Or the flap can be lengthened by extending the design into the hairline, accepting some hair on the distal aspect of the flap. In the following example, this delightful lady, born with congenital syphilis (Figure 8–9), had been subjected to multiple attempts to repair nasal maldevelopment and collapse since youth. Bilateral nasolabial flaps, a widely based forehead flap, ear, rib and cranial bone grafts, and multiple local flaps had been used over the years. The nose was short, irregular and shapeless. A transverse scar, about 1 cm below the hairline, traveled across the superior forehead from one temple to the other. Two vertical scars also extended, superiorly, from the left medial brow and the mid right brow. They joined the superior transverse scar. These scars were the sequelae of the old forehead flap. The unused portion of the old flap had been returned to the forehead some years before. The residual donor defect was then closed by advancing the scalp, inferiorly. Unfortunately, it also shortened the forehead and created a scar which completely transversed the forehead several centimeters under the hairline. Presumably, the past surgeon utilized a wide pedicle to ‘preserve flap vascularity’. This is unnecessary. To close the donor site, the residual flap was returned to the forehead. If you design a flap with such a wide pedicle, its wide base must be replaced to repair the forehead. 256
Expansion of the Forehead
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Figure 8–9
Unfortunately to ‘minimize donor deformity,’ and close any remaining open gap, the forehead was incised transversely and the scalp advanced, inferiorly. Both maneuvers significantly limited the harvest of another flap. A plan was formulated. The nose would be lengthened with hingeover lining flaps, supported and shaped with a dorsal rib graft, rib alar battens, a columellar strut and an ear cartilage tip graft. The forehead would be expanded within the territory of the previous forehead flap, which was less than 5 × 5 centimeters in all dimensions — too narrow to resurface a nose and too short to reach the defect.
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During a preliminary procedure (Figure 8–10), a skin expander was placed under the old forehead flap territory. It was positioned through a midline scalp incision. Two
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Figure 8–10
Expansion of the Forehead
months later, after expansion, support grafts were placed over hingeover lining flaps and an expanded full-thickness paramedian forehead flap was harvested and transferred for cover. The donor site was approximated. The gap which remained in the forehead was allowed to heal secondarily. An intermediate operation was performed to thin the flap excess and sculpt the soft tissues. The pedicle was subsequently divided. No revision has been performed (Figure 8–11).
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Figure 8–11
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This nose is collapsed and foreshortened after several rhinoplasties and subsequent destruction from Wegener granulomatosis (Figure 8–12). Many years before, a classic Millard Seagull forehead flap was performed to reconstruct the nose. The retracted tip elements were released, allowing the inferior nose to fall back to its normal position. The resultant midvault defect was later lined with delayed hingeover flaps and covered with a two-stage forehead flap; its gull wing scar criss-crosses her central forehead. In the interval, the result deteriorated. However, the Wegener granulomatosis remained inactive. The patient requested further reconstruction.
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Expansion of the Forehead
The size of the donor site was increased by preliminary expansion (Figure 8–13). But the reliability of the skin, distal to the old transverse scar, was still in question. Fortunately, by increasing the ‘width’ of forehead, the flap could now be designed to the side of the vertical component, avoiding it completely. The transverse component of the old scar remained within the flap’s territory. Once the dimensions of the available tissues were adequate, the flap was outlined and delayed by staged incisions about its periphery. Partial implant extrusion is visible at the time of transfer. Local lining hingeover and random nasolabial flaps were delayed and shifted into position, at the same time. Then a second delayed expanded and now full-thickness forehead flap was transferred in three stages to resurface primary rib grafts and lining flaps. Much of the donor site was closed primarily. A small gap healed secondarily. The repair was otherwise uneventful.
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Figure 8–13
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Two months after division, her appearance and function are improved (Figure 8–14). Scars will mature.
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The Technique of Forehead Expansion
The Technique of Forehead Expansion 1. 2.
Determine the correct site for expander placement, above the desired pedicle. Create a subfrontalis pocket slightly larger than a 4-cm rectangle smooth expander by blunt dissection. The expander is placed through a radial incision within the scalp. An old scar can also be employed. 3. Position the expander. Minimize folds by injecting several cubic centimeters of saline into the expander but avoid excessive tension. Close the scalp incision in layers. Prophylactic antibiotics are used. A drain may be placed. 4. Some weeks later, the expander is injected weekly over 6 to 10 weeks until the overlying skin is stretched to the proper dimensions. Wound tension, blanching and patient discomfort are useful parameters to avoid overfilling at each injection. 5. Measure over the dome of the implant, until adequate length and width of the proposed flap is achieved and sufficient tissue is available to resurface the defect. The goal is to enlarge available forehead skin for transfer to the nose. The goal is not to assure primary closure of the residual forehead defect — any gap can be allowed to heal secondarily. 6. Beware of visible or palpable knuckles, thinning or a bluish color visible through the overlying skin, which may presage extrusion. Often the surgeon can continue filling the expander and work through a temporary knuckle. Fortunately, if a minor exposure occurs, it is often late in the expansion. Occasionally, the expansion can cautiously continue. Most often even if expansion must stop a limited wound breakdown will not preclude using the flap. Beware infection. Sterile technique is important. If infection is noted, it can sometimes be controlled with antibiotics and closed drainage but expander removal may be necessary. 7. If the vascularity of the flap’s territory is in doubt due to past scars, the proposed flap can be surgically delayed, in stages. Once the expansion is completed, the flap is outlined over the dome. The skin is incised with a scalpel. Then the dissection is carried to the capsule with the blunt tip of a cautery. If the capsule is entered, it is repaired. The skin incision is closed in layers. 8. At the time of flap transfer, the template is positioned over the expander to determine the correct dimension, border outline and length of the required flap. When using expanded skin, it may be safer to design the flap a few millimeters larger than the template to make up for recoil. 9. When ready for transfer, the flap is incised. The expander is removed with its port and a full thickness flap moved to the donor site. The fibrous rind which forms over the frontal bone, along the periphery of the capsule, will spontaneously resolve. It is often recontoured by excising the excess scar with an electrocautery to smooth the bony forehead. To allow easy transposition of the flap and proper length, the flap must be elevated across the supraorbital rim, opening and transecting the capsule at the flap’s base. The dissection is continued over the supraorbital rim towards the medial canthus. The entire expander capsule, with its contracting myofibroblasts, is routinely excised. 10. Frightening elastic shrinkage of the flap occurs on elevation of the expanded skin from the surface of the expander. Fortunately, the flap stretches back to its initial expanded dimensions when sutured to the nasal inset. However, a strong support framework is needed to prevent late flap recoil and skin contraction. 11. During the intermediate operation, if a significant scar lies within the expanded flap’s territory, the skin can be elevated as a bipedicle, extending from the brow
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to the nasal columellar and rim. This maintains the maximum blood supply when contouring the underlying soft tissue or modifying the cartilage support.
General Guidelines to Protect and Repair the Forehead Donor Site 1. 2. 3. 4.
5.
A Figure 8–15
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Routinely use the vertical paramedian forehead flap design. Allow any gap within the superior forehead, which cannot be closed primarily, to heal secondarily. Revise the forehead scar secondarily, if necessary. In most circumstances after flap harvest, the defect which remains after harvest lies within the superior forehead. The inferior forehead donor, after transposition of its narrow 1.2–1.5 cm pedicle, can be closed primarily at transfer. Later, at pedicle division, most of the excess proximal pedicle is discarded. Only its most inferior aspect is replaced as a small inverted ‘V’ to restore the medial eyebrow. The remnant will simulate the frown crease. Occasionally, if the defect extends high onto the radix or its width extends laterally towards each medial canthus, the inferior forehead cannot be closed at the time of initial flap transfer. A gap remains in the inferior forehead (as well as the superior forehead) which cannot be closed primarily, even after advancement of the residual adjacent forehead skin. It is left open or temporarily skin grafted. At pedicle division, the unused proximal pedicle is returned to the donor site. An
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General Guidelines to Protect and Repair the Forehead Donor Site
area of secondary healing (or a temporary skin graft) is excised and the unused proximal skin base, with medial eyebrow hair, is returned to the inferior forehead. The superior gap higher under the hairline is allowed to heal secondarily. After multiple failed repairs, a third forehead flap was harvested in this patient (Figure 8–15). The size and height of the defect and donor availability precluded primary
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Figure 8–15, Continued
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Chapter • 8 • The Basics, Old Scars, Previous Forehead Flaps, Delay and Expansion
closure of the inferior forehead at transfer. The donor site was left open, initially. At pedicle division, the unused proximal portion of the flap was returned to the donor site to facilitate closure and restore the medial brow. The residual superior aspect of the defect was left to heal secondarily. 6.
7.
8. 9.
Consider pre-expansion of the flap but only when needed to increase the length or width of the available forehead. This is performed to construct a nose. It is not done to ease donor closure. Consider expansion of the forehead skin adjacent to the forehead flap. This is ordinarily performed after flap transfer to ease repair of the forehead defect which remains after flap harvest. This is rarely needed but remains an option. The nose must come first and the forehead second! Build the nose. Later expand the residual forehead to improve the donor site. Rarely, skin graft the residual gap which remains after forehead flap transfer. Rarely, resurface the entire forehead unit with a full-thickness skin graft. A tight shiny skin graft can simulate the expected tight shiny forehead unit. The skin graft border scars lay hidden in the junction between units and are not distracting.
In this patient (Figure 8–16), extensive recurrent basal cell carcinoma necessitated a total nasal amputation after a prior reconstruction which had resurfaced the nose with an oblique median forehead flap. The old donor site had been closed with a thigh skin graft. A second nasal repair was planned using a free radial forearm flap for lining, rib grafts for support, and a right paramedian forehead flap for total nasal resurfacing. Complica-
A Figure 8–16
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B
General Guidelines to Protect and Repair the Forehead Donor Site
tions, discussed in chapter 21, required the harvest of a third forehead flap. At the time of pedicle division, the forehead was significantly distorted by the old thigh split thickness skin graft and extensive areas of secondary healing. Supra-clavicular skin was pre-expanded. Scar and old skin graft were excised within the forehead unit. The forehead donor site was grafted with full-thickness skin as a complete unit (Figure 8–17).
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Figure 8–17
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E
Figure 8–17, Continued
The appearance of the forehead is relatively good after total unit grafting. The expected tight shiny and relatively uniform character of the skin graft replicates the smooth shiny tight character of the normal forehead. The graft’s border scars lay relatively hidden along the periphery of the unit adjacent to the hair line, the eyebrows, and the junction of the medial and lateral forehead subunits along the temporal creast. The forehead is a peripheral unit of lesser priority.
Guidelines for the Excessively Short Forehead (Less Than Three to Four Centimeters) 1.
2. 3.
Extend the design into the hairline. Accept hair on the nose. Shave, pluck, depilate, laser, or destroy the subdermal hair bulbs by excision and coagulation, secondarily. Lower the flap pivot point by extending its base across the eyebrow towards the medial canthus. This effectively lengthens the flap and improves its reach. Rarely, expand the available height of forehead tissues by pre-expansion of the donor site.
Remember the nose is the primary concern. A good nose with a few hairs is acceptable to patients — a bad nose without hair is a failure. 268
Guidelines for Harvesting Multiple Forehead Flaps
Guidelines for Harvesting Multiple Forehead Flaps 1. 2. 3. 4.
Check the position and length of old scars. Determine the available forehead surface versus the recipient requirement. Consider use of the contralateral pedicle. Use a full-thickness forehead flap to increase vascular safety when old scars or past dissection may have interfered with the normal blood supply. 5. Delay the flap across an old scar, if one is present or if the pedicle is suspected of having been injured during previous surgery. 6. Consider tissue expansion, if the available forehead surface seems inadequate. 7. Consider using a non-paramedian forehead flap design based on other intact axial vessels (Scalping or Sickle flap). 8. If the donor site cannot be closed primarily under the hairline, allow any residual gap to heal secondarily. 9. If the inferior forehead cannot be closed primarily due to the size and location of the nasal defect, return the unused proximal pedicle to the forehead at its division to facilitate its closure and the appearance of the eyebrow. 10. In extreme circumstances, when the forehead has been extensively destroyed by previous injury or multiple forehead flap harvests, excise scar and residual skin within the unit and resurface the entire forehead with a one-piece full-thickness skin graft, obtained after expansion of supraclavicular skin.
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C H A P T E R
Treat the primary defect first. Do not let concern for the secondary defect endanger the final results. Sir Harold Gillies
It takes courage to harvest forehead skin from an already anxious and fearful patient. But the deformed face requires correction. Fortunately, knowledge, experience, and proper technique build confidence. The nose can be repaired with little injury to the donor site. The final result necessitates doing the ‘right thing’. Take whatever you need from the forehead to make the nose!
The Basics The size, vascularity and quality of forehead skin make it the first choice for major nasal repair. Its expansive surface is perfused from multiple arcades of axial vessels which enter along its periphery. The paramedian forehead flap design, based inferiorly on the supratrochlear vessels, seems best. It harvests skin high under the hairline — away from the central and most visibly important facial landmarks. Its narrow pedicle — 1.2 to 1.5 cm in width — allows primary closure of the inferior forehead, leaving a single-line scar above the brow, which is minimally intrusive. The eyebrow is not distorted or medialized on return of the proximal pedicle base to the eyebrow. The flap is elevated and transferred in two or three stages. At the time of transfer, the residual forehead is undermined bluntly in the subfrontalis plane over the periosteum, superiorly and laterally into each temple. Bleeding is modest and postoperative hematoma does not occur. Under moderate tension, several key tacking sutures are placed, exiting one to two millimeters from the wound edge. Although they remain for 10 days, because they are so close to the wound edge, a significant suture mark does not follow. Then a layered closure, using 4-0 and 5-0 permanent or slowly absorbing sutures, is performed to approximate the frontalis muscle and then the subcuticular skin, followed by 6-0 silk or plain gut suture for the skin. A superior dog-ear is excised within the scalp. If the forehead cannot be closed primarily, the gap remains superiorly positioned. It is allowed to heal secondarily. A petrolatum impregnated fine gauze is applied to cover the raw periosteum and fixed temporarily with 5-0 chromic suture. The patient can shampoo the following day and wash the nose and forehead. The impregnated gauze dressing is removed in 7 to 10 days. Healthy granulation tissue slowly fills the open gap. It is protected with a light nonadherent dressing, if desired. Daily washing
Chapter • 8 • The Basics, Old Scars, Previous Forehead Flaps, Delay and Expansion
continues. The wound fills with granulation tissue, contracts and spontaneously reepithelializes. Intraoperatively and postoperatively, the frontal periosteum should be protected from trauma and desiccation. But it will heal satisfactorily, even if large areas of periosteum are denuded and frontal bone exposed. Wait and let nature heal itself. Depending on elasticity of the tissue, the presence of old scars, or the harvesting of a past forehead flap, the donor site can often be closed primarily. This applies if the area that requires resurfacing is limited to the width of a single subunit — the ala, the ala and sidewall, the tip or the tip and dorsum. Note, however, the expanse of forehead required to resurface the convex tip or multiple units is frequently underestimated. In such cases, a gap may remain superiorly and should be allowed to heal secondarily. The open area may vary from a few millimeters to several centimeters. The adjacent normal forehead tissues stretch by autoexpansion. Frequently, a small gap heals spontaneously within 3 to 6 weeks. If desired, the resultant forehead scar can be excised, the wound edges undermined for 1 to 2 cm and the incision reclosed, in layers, at the time of pedicle division. Larger forehead defects heal spontaneously over 4 to 10 weeks. The gap granulates, re-epithelializes and contracts — an almost 4-cm defect may shrink to 1.5–2 cm. Although the scar will be red and raised for 2 to 6 months, it will not be depressed. The final forehead contour is excellent. Depending on scar quality, it can be excised and the adjacent forehead re-advanced in one to two stages, 4 to 6 months after pedicle division. In most cases, it can be completely excised or nearly completely excised during a late revision. Often, although present, the scar is unobtrusive and is not revised. In the typical repair, no revision is performed. The nose looks good and the forehead does not appear injured. In more difficult reconstructions, refining the reconstructed nose by sculpting the alar crease, recreating the nasolabial fold or thinning the nostril will be helpful. Revision of the forehead scar is easily combined with these procedures. Forehead scar revisions are primarily performed only in complex repairs which required a large flap. A forehead allowed to heal secondarily will always have a more aesthetic appearance than one closed with a skin graft or one distorted and denervated by extensive scalp or forehead advancements. If a gap remains in the superior forehead which cannot be closed, let it heal secondarily. Examination of the many cases illustrated in the text should put the surgeon at ease. When I ask myself the question — ‘Is the scar worth it?’ — my answer is always ‘yes!’ For example, this 14-year-old girl (Figure 8–1) underwent a three-stage forehead flap and support replacement to reconstruct her nose destroyed by an infantile hemangioma. A large flap was harvested to resurface the unit. The gap in the superior forehead was allowed to heal secondarily. Each week, the residual defect became smaller. At 8 weeks, prior to pedicle division, the wound was nearly healed. Months later, during a revision, the forehead scar was excised and the adjacent skin advanced and reapproximated. A small remaining gap was left to heal spontaneously.
Delay and Forehead Expansion Foreheads vary in height and width (which are determined by hairline position), laxity, the presence of scars, prior injury or past forehead flap harvest. 240
Delay and Forehead Expansion
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Figure 8–1
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Chapter • 8 • The Basics, Old Scars, Previous Forehead Flaps, Delay and Expansion
E
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Figure 8–1, Continued
Practically speaking, when faced with a nasal defect, the surgeon must ask two questions: Is skin available to resurface the nose? Can it be transferred with a reliable blood supply? Perhaps reflecting a lack of confidence, surgeons become misdirected away from the important problems — recreating outline, symmetry, and contour. Often they look to unnecessary maneuvers or technology to lessen their anxiety. Most often, delay of the flap or expansion of the donor site is undertaken — not because it ‘should be’ but because it ‘can be’. Unless specifically indicated, neither method improves the final result of nasal repair. Both delay its completion and both add their own inherent disadvantages and risks of complications to an already complex situation. Do not waste time or energy on the forehead unless it will contribute to the final result. The forehead is a very forgiving donor site — expansive, highly vascular, self-healing and lending itself to secondary revision. Employ delay or expansion only when appropriate. Such cases are the exception. Nature blessed the reconstructive surgeon with the forehead to repair a nose. The fear of late forehead deformity is a misdirected priority. Ask yourself: Is this maneuver going to help build a better nose or will it divert attention away from the truly difficult aspects of repair? — taking bits and pieces of expendable tissue and recreating a facsimile that looks and breathes like a nose. 242
Delay and Forehead Expansion
Surgical delay Under most circumstances, delay of a forehead flap prior to transfer is neither helpful nor required. It is almost never needed when harvesting tissue from a previously uninjured and virgin forehead. In occasional cases, a surgical delay of the flap is employed, prior to transfer, to enlarge the available flap territory or to augment its blood supply and improve vascular safety. Consider surgical delay of a forehead flap when: 1. 2.
3.
4.
5. 6.
A significant old scar, which may interfere with its axial vessels, lies within the proposed flap territory. The pedicle’s named blood supply is suspect due to previous injury (prior trauma, history of a previous overly aggressive browlift, multiple past forehead flaps). Unusually complex extensions of flap design are required (very uncommon). The perfusion of a paramedian forehead flap is excellent especially if it has not been thinned. The flap design extends across one vascular territory into the territory of another flap. For example, the axial blood supply of the Sickle flap is based on the superficial temporal artery of the scalp. This scalp vessel collateralizes with the supraorbital and supratrochlear systems which are the primary blood supply to the lateral forehead. Surgical delay of a Sickle flap ensures the safe transfer of skin within the secondary forehead angiosome. Because the supratrochlear vessels reliably perfuse the forehead, high into the hairline, a paramedian flap of almost any size can be transferred without delay. The patient is an end stage smoker or has a history of radiation. During a complementary procedure, the surgeon is in doubt and a preliminary operation is required for other reasons (a prefabrication, a delay of lining hingeover flaps, etc.).
To delay a flap, the dimension and outline of the defect, which requires resurfacing, are determined. The template is positioned on the forehead donor site over the territory of the planned pedicle and marked with ink. This will routinely be the supratrochlear vessels. The proposed flap edges are incised to periosteum. In many cases, a few millimeters of the peripheral outline are left intact at the flap’s columellar and alar tips, to ensure that the flap can initially handle the intervention. These minor tissue connections may be transected in the office prior to formal flap transfer. Because all significant contributions to the forehead blood supply arise from peripheral axial vessels and not from the areolar connections to the underlying periosteum, the flap does not need to be elevated to stimulate the increased vascularization associated with surgical delay. The diffuse sources of blood supply, which normally contribute to the forehead survival, are eliminated, ‘training’ the flap to survive on a single source at the pedicle’s base. One month later, vessels at the base of the flap are enlarged. Overall vascularity is increased, the territory available for transfer is enlarged, and perfusion across an old scar supplemented, if needed. Always consider the many disadvantages of delay. 243
Chapter • 8 • The Basics, Old Scars, Previous Forehead Flaps, Delay and Expansion
1. 2.
3.
Additional stages, added cost, and prolongation of the overall reconstruction. The inability to alter flap dimensions at the time of transfer — length, width and border outline. Although it may be possible to create a template which will accurately define the recipient requirements, it is difficult to precisely determine the dimensions and outline of a forehead flap before recreating the defect, returning normal to normal and placing support grafts over reconstructed lining. Possible flap induration and loss of pliability. This should not be a significant problem as long as the flap itself is not undermined during the delay. It should be incised along its borders, but not elevated, during the preliminary operation to improve its blood supply.
For instance in this patient (Figure 8–2), significant facial scarring followed smallpox in infancy. During his teenage years, the cheeks were resurfaced with split-thickness skin grafts, and the nose with a left lateral horizontal forehead flap, pedicled on the superficial temporal artery. After pedicle division, the residual flap was returned to the forehead and the remaining right temple defect was skin grafted. When seen many years later, he desired improvement. Lengthy horizontal scars lay across the forehead both beneath the hairline and above the brow within the territory of a planned left paramedian forehead flap. Survival of the skin distal (superior) to two transverse scars was unlikely without surgical delay. Prior to nasal repair, the left supratrochlear vessels were identified and a full-thickness paramedian forehead flap was outlined. It was incised through the skin to the periosteum except for a few millimeters at the tip of the columella and both alar bases. Four weeks later, nasal lining was restored with hingeover flaps to lengthen the nose. Primary cartilage batten grafts were positioned to support the alae. The flap was elevated with all its layers and transferred without incident. Note that two transverse scars cross the flap’s territory. But the flap was well vascularized and healed without incident. The large gap in the forehead was allowed to heal primarily.
244
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D
E
Figure 8–2
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Chapter • 8 • The Basics, Old Scars, Previous Forehead Flaps, Delay and Expansion
One month later, the first of two intermediate operations was performed (Figure 8–3). The defect extended from high on the radix to the nasal base. Total re-elevation and
A
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Figure 8–3
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Delay and Forehead Expansion
E
F
Figure 8–3, Continued
debulking of frontalis muscle and subcutaneous fat over such a large area, crossed by full-thickness scars, would put the flap at risk. So initially, forehead skin with 2 to 3 mm of subcutaneous fat was re-elevated over the inferior two thirds of the nose. The transverse scar which crosses the proximal aspect of the flap is visible, crosshatched with ink. For vascular safety, the columella inset was not re-elevated. However, extensive subcutaneous sculpturing of excess frontalis and subcutaneous fat as well as placement of a delayed primary tip graft was performed. The flap was reapproximated to the recipient site with peripheral and quilting sutures. Despite profuse vascularity at the time of initial transfer to the nose 4 weeks before, the tip of the right ala became superficially ischemic, over several days. Fortunately this healed without significant incident, although the alar base became slightly malpositioned. Six weeks later, a second intermediate operation was performed to further sculpt the proximal dorsum and nasal root. The flap was re-elevated from the superior inset to expose the midnose and radix, the excess soft tissues excised and the flap returned to the sculpted recipient site. The forehead flap was divided one month later. Vascularity remained excellent during the later procedures. 247
Chapter • 8 • The Basics, Old Scars, Previous Forehead Flaps, Delay and Expansion
Seen, just 6 weeks later, in this early postoperative photograph (Figure 8–4), his nasal appearance is significantly improved. Despite the harvest of a horizontal flap with skin grafting of the donor site and a later paramedian forehead flap, with secondary healing of the second new donor gap, the appearance of the forehead has not been impaired.
A
C Figure 8–4
248
B
Scars within the Forehead
Significant scarring within the paramedian territory necessitated technique modification in this patient. To maintain maximal vascularity, the flap was delayed. A full-thickness forehead flap was employed to include all vascular layers. During the intermediate operation, the flap was re-elevated in stages, maintaining a partial distal inset to augment the blood supply coming from the brow. Interestingly, the flap tolerated initial transfer without incident. Superficial necrosis developed only during the first intermediate operation, suggesting this may have been a technical error due to too superficial re-elevation or tension on closure. Fortunately, the borderline vascularity of the right alar tip did not significantly limit the result.
Scars within the Forehead Determine the recipient requirements and outline the available surface area of the forehead. If a scar lies within the proposed flap territory the surgeon must determine the site, direction, depth, and length of the scar. A transverse scar puts the flap at greater risk. A review of old operative reports may clarify whether the injury extended only superficially, injuring only the random cutaneous blood supply, deeper through the galeal frontalis or directly to the vascular pedicle at the flap’s base. Doppler examination of the supratrochlear artery and its ascending vertical branches may confirm their presence or absence. If the vessels can be followed up the forehead, the surgeon can be reassured that they are intact. This would also apply if history suggests that the pedicle may have been injured by past injury or surgery.
Options when a scar lies within the flap territory 1.
2.
3. 4.
5.
6.
In many cases, it is possible to quickly determine that a visible scar is of little consequence. A scar can be disregarded if it is short, vertical, superficial, or the presence of flap’s named vessel can be verified by Doppler. The surgeon may avoid the scarred area entirely. The opposite contralateral pedicle can be used to transfer skin from the opposite side of the forehead, if it is adequate in size and vascularity. This has the disadvantage of increasing the distance to the defect and the need for a longer flap to reach the defect on the opposite side of the nose. The flap territory can be surgically delayed to augment its blood supply. This is useful when the surgeon has special concern. The flap can be elevated as a full-thickness flap to maintain its maximal blood supply. Under such circumstances, the full-thickness forehead flap is thinned later during the intermediate operation. It is re-elevated as a bipedicle extending from the brow to the columella and nostril rims. Because the flap remains well vascularized from both the proximal pedicle and distal inset during the second stage, the scar should be of significantly less concern because it lies within the middle of the flap’s surface. Even if the forehead is scarred, an area of virgin skin may be available to expand. An area of the forehead is transferred that avoids the area of concern. In rare instances when both supratrochlear arteries have been ablated and extensive scarring may exist within the inferior forehead, available forehead skin can be transferred on other vascular pedicles — e.g. use a scalping flap or sickle flap, rather than a paramedian flap based on the supratrochlear vessels. 249
Chapter • 8 • The Basics, Old Scars, Previous Forehead Flaps, Delay and Expansion
For example, this patient presented after a repair of an extensive midfacial nasal, canthal, and cheek defect (Figure 8–5). Bilateral cheek, eyelid, and scalp advancement and rotation flaps dragged the borders of the wound medially to close the holes. The nasal dorsum was flat and the tip pulled superiorly. A plan was outlined. A fullthickness release of her nasal tip would reposition it to its normal position. A septal composite flap would be pulled out of the pyriform aperture to restore a septal partition and provide lining. Multiple dorsal, sidewall and columellar rib cartilage grafts would support the repair and forehead skin would resurface the midvault and nasal sidewalls. Unfortunately the prior repair complicated future reconstruction. Both supratrochlear and supraorbital arteries had been transected. An oblique scar extended superiorly from the left medial brow into the right temple. Incisions lay within both upper lids, along the lower lids, and lateral to both nasolabial folds. However, skin was available in the left upper forehead and could be transferred based on superficial temporal vessels. This is the Sickle flap, as described by New.
250
Scars within the Forehead
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C Figure 8–5
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Skin within the forehead receives its primary blood supply from the supratrochlear and supraorbital vessels and a secondary perfusion from the lateral scalp. During an initial operation (Figure 8–6), a forehead flap, based on the left superficial temporal and postauricular vessels, was delayed by incising its periphery. This skin was too valuable to risk and the superficial temporal vessels may not reliably perfuse this secondary angiosome without delay. At the same time, the residual normal tip was repositioned by incising the nose transversely into the nasal cavity. This reopened the significant full-thickness defect of the midvault. A composite septal flap was swung out of the nasal cavity to fix the position of the nasal tip. It also provided lining for the future nasal vault. At a later procedure, mucoperichondrium of the composite flap was hinged laterally bilaterally. Rib grafts were placed for dorsal, columellar, and sidewall support. And the Sickle flap was transferred to resurface the upper and middle nose. During an intermediate sculpting operation to improve the nasal contour, an expander was placed under the intact right forehead (Figure 8–7).
A Figure 8–6
252
B
Scars within the Forehead
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B
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D
Figure 8–7
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After expansion, the forehead flap pedicle was divided and the residual flap was returned to the scalp. The expanded right forehead skin was elevated and pulled laterally to resurface the remaining donor defect within the left forehead. Postoperatively (Figure 8–8), a normal nasal contour has been re-established. The paramedian forehead flap should be the surgeon’s first choice. However, scars within its territory or injury to the supratrochlear vessels do not preclude the use of forehead skin, based on other named vessels. Historically, although more morbid, the Converse Scalping flap has been used most often.
The Technique of Forehead Flap Delay 1.
2.
A Figure 8–8
254
Design a flap template with the required dimension, outline and length to supply the defect. Remember that it cannot be altered or extended at the time of transfer. Transfer the template to the donor site and mark with ink. Then stop and check the measurements a second time and reconfirm your requirements. Reconfirm adequate flap length, the position of the pivot point and flap reach. Mark twice or more and cut once.
B
Expansion of the Forehead
3.
4. 5.
6.
Delay the flap, making peripheral incisions through the skin, subcutaneous tissues and frontalis down to the areolar layer over the frontal bone. Because little blood supply enters from the frontal bone, no undermining is required to stimulate vascularization of the flap by delay. Undermining causes unnecessary induration and edema and has no advantage. Frequently the entire border outline will be incised in one stage, leaving just a few millimeters of intact skin at the columella or alar tips. If the flap seems at greater risk, it may be delayed in one or two stages, leaving 4 mm bridges of intact skin along its peripheral border and at the tip and at each alar extension. These are incised at two week intervals until its border is completely incised. At transfer one month later, elevate the flap with all its layers as a full-thickness forehead flap. Thin the flap’s excess soft tissue during the intermediate operation to ensure vascular safety. Consider re-elevating the flap incompletely or in multiple stages. It can be re-elevated while maintaining a distal inset during the intermediate stage or, if the recipient site and its required flap is large and its vascularity in question, it can be debulked in stages during a second intermediate operation. Occasionally, in the tight and scarred forehead, both tissue expansion and delay are required to provide an adequate surface area for repair and to ensure vascularity. First, expansion is completed. Then the expanded skin is delayed, in stages. The required defect pattern is applied over the surface of the expander and border incisions are made through the skin, subcutaneous tissue and frontalis muscle to the underlying capsule. When performed using loupe magnification, the risk of injury to the underlying implant is real, but injury is avoidable. After incision of the skin with a scalpel, the underlying soft tissue can be safely divided with the blunt tip of a cautery. Frequently, the capsule space will be entered but this can occur without incident. The wound edges are reapproximated and a layered closure performed. The outline of the flap may be delayed in stages, if needed.
Expansion of the Forehead In special circumstances, pre-expansion of the forehead will improve the surgeon’s ability to reconstruct a nose. It can increase the amount of tissue available for transfer. In unusual circumstances, it is useful. However, it is rarely necessary. The surgeon must measure the dimension of the needed cover skin and compare it to the size of forehead available for nasal resurfacing. A ‘virgin’ forehead can supply enough skin to resurface any nasal defect. Most defects are relatively small. The forehead is easily closed primarily. When total nasal resurfacing is required, a gap may remain which cannot be closed. However, secondary healing heals the wound. Autoexpansion and contraction decrease the size of the late scar. A scar revision can be performed later, if desired. Occasionally, the donor site is limited by old scars or past harvest. In these unusual circumstances, pre-expansion can enlarge the excess available for nasal repair. It is not employed, however, to make closure of the forehead easier. Preliminary forehead expansion has many disadvantages. 255
Chapter • 8 • The Basics, Old Scars, Previous Forehead Flaps, Delay and Expansion
1. 2. 3. 4. 5. 6.
7.
8. 9.
It delays the nasal repair, increases the number of operative stages and adds additional expense. It necessitates multiple office visits and additional supplies. It subjects the patient to a lengthy period of social isolation due to its unusual, but temporary, deformity. It risks infection and extrusion. It causes frontal bone erosion and callus formation. Unexpected flap recoil may occur after transfer, if the stretched expanded skin is not rigidly braced with a hard tissue framework to maintain its proper dimension. It is difficult to outline the flap template on the globelike surface of the expander, especially where the expanded skin joins the normal adjacent unexpanded skin. An expander makes surgical delay of the flap more complicated. Expansion does not reliably improve the blood supply of the flap.
Forehead expansion should be considered: 1.
2.
In an especially tight forehead with limited available skin — one with extensive forehead scarring or prior forehead flap harvest. Expansion can increase the length and width of available skin by expanding any remaining useful skin territory. The surgeon may expand the proposed flap, prior to its transfer, or expand the residual forehead adjacent to a planned flap, using the expanded skin for secondary closure of the primary forehead defect. Very rarely, in an especially short forehead (less than 3–4 cm in height), pre-expansion can be used to increase flap length and minimize the amount of hair transferred to the nose.
However in most instances, expansion is not employed. The pedicle is simply incised, more inferiorly, across the brow. This lowers the pivot point and brings the base of the flap closer to the defect. Or the flap can be lengthened by extending the design into the hairline, accepting some hair on the distal aspect of the flap. In the following example, this delightful lady, born with congenital syphilis (Figure 8–9), had been subjected to multiple attempts to repair nasal maldevelopment and collapse since youth. Bilateral nasolabial flaps, a widely based forehead flap, ear, rib and cranial bone grafts, and multiple local flaps had been used over the years. The nose was short, irregular and shapeless. A transverse scar, about 1 cm below the hairline, traveled across the superior forehead from one temple to the other. Two vertical scars also extended, superiorly, from the left medial brow and the mid right brow. They joined the superior transverse scar. These scars were the sequelae of the old forehead flap. The unused portion of the old flap had been returned to the forehead some years before. The residual donor defect was then closed by advancing the scalp, inferiorly. Unfortunately, it also shortened the forehead and created a scar which completely transversed the forehead several centimeters under the hairline. Presumably, the past surgeon utilized a wide pedicle to ‘preserve flap vascularity’. This is unnecessary. To close the donor site, the residual flap was returned to the forehead. If you design a flap with such a wide pedicle, its wide base must be replaced to repair the forehead. 256
Expansion of the Forehead
A
B
Figure 8–9
Unfortunately to ‘minimize donor deformity,’ and close any remaining open gap, the forehead was incised transversely and the scalp advanced, inferiorly. Both maneuvers significantly limited the harvest of another flap. A plan was formulated. The nose would be lengthened with hingeover lining flaps, supported and shaped with a dorsal rib graft, rib alar battens, a columellar strut and an ear cartilage tip graft. The forehead would be expanded within the territory of the previous forehead flap, which was less than 5 × 5 centimeters in all dimensions — too narrow to resurface a nose and too short to reach the defect.
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During a preliminary procedure (Figure 8–10), a skin expander was placed under the old forehead flap territory. It was positioned through a midline scalp incision. Two
A
C 258
B
Figure 8–10
Expansion of the Forehead
months later, after expansion, support grafts were placed over hingeover lining flaps and an expanded full-thickness paramedian forehead flap was harvested and transferred for cover. The donor site was approximated. The gap which remained in the forehead was allowed to heal secondarily. An intermediate operation was performed to thin the flap excess and sculpt the soft tissues. The pedicle was subsequently divided. No revision has been performed (Figure 8–11).
A
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Figure 8–11
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Chapter • 8 • The Basics, Old Scars, Previous Forehead Flaps, Delay and Expansion
This nose is collapsed and foreshortened after several rhinoplasties and subsequent destruction from Wegener granulomatosis (Figure 8–12). Many years before, a classic Millard Seagull forehead flap was performed to reconstruct the nose. The retracted tip elements were released, allowing the inferior nose to fall back to its normal position. The resultant midvault defect was later lined with delayed hingeover flaps and covered with a two-stage forehead flap; its gull wing scar criss-crosses her central forehead. In the interval, the result deteriorated. However, the Wegener granulomatosis remained inactive. The patient requested further reconstruction.
A
B Figure 8–12
260
C
Expansion of the Forehead
The size of the donor site was increased by preliminary expansion (Figure 8–13). But the reliability of the skin, distal to the old transverse scar, was still in question. Fortunately, by increasing the ‘width’ of forehead, the flap could now be designed to the side of the vertical component, avoiding it completely. The transverse component of the old scar remained within the flap’s territory. Once the dimensions of the available tissues were adequate, the flap was outlined and delayed by staged incisions about its periphery. Partial implant extrusion is visible at the time of transfer. Local lining hingeover and random nasolabial flaps were delayed and shifted into position, at the same time. Then a second delayed expanded and now full-thickness forehead flap was transferred in three stages to resurface primary rib grafts and lining flaps. Much of the donor site was closed primarily. A small gap healed secondarily. The repair was otherwise uneventful.
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Figure 8–13
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Chapter • 8 • The Basics, Old Scars, Previous Forehead Flaps, Delay and Expansion
Two months after division, her appearance and function are improved (Figure 8–14). Scars will mature.
A
C Figure 8–14
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The Technique of Forehead Expansion
The Technique of Forehead Expansion 1. 2.
Determine the correct site for expander placement, above the desired pedicle. Create a subfrontalis pocket slightly larger than a 4-cm rectangle smooth expander by blunt dissection. The expander is placed through a radial incision within the scalp. An old scar can also be employed. 3. Position the expander. Minimize folds by injecting several cubic centimeters of saline into the expander but avoid excessive tension. Close the scalp incision in layers. Prophylactic antibiotics are used. A drain may be placed. 4. Some weeks later, the expander is injected weekly over 6 to 10 weeks until the overlying skin is stretched to the proper dimensions. Wound tension, blanching and patient discomfort are useful parameters to avoid overfilling at each injection. 5. Measure over the dome of the implant, until adequate length and width of the proposed flap is achieved and sufficient tissue is available to resurface the defect. The goal is to enlarge available forehead skin for transfer to the nose. The goal is not to assure primary closure of the residual forehead defect — any gap can be allowed to heal secondarily. 6. Beware of visible or palpable knuckles, thinning or a bluish color visible through the overlying skin, which may presage extrusion. Often the surgeon can continue filling the expander and work through a temporary knuckle. Fortunately, if a minor exposure occurs, it is often late in the expansion. Occasionally, the expansion can cautiously continue. Most often even if expansion must stop a limited wound breakdown will not preclude using the flap. Beware infection. Sterile technique is important. If infection is noted, it can sometimes be controlled with antibiotics and closed drainage but expander removal may be necessary. 7. If the vascularity of the flap’s territory is in doubt due to past scars, the proposed flap can be surgically delayed, in stages. Once the expansion is completed, the flap is outlined over the dome. The skin is incised with a scalpel. Then the dissection is carried to the capsule with the blunt tip of a cautery. If the capsule is entered, it is repaired. The skin incision is closed in layers. 8. At the time of flap transfer, the template is positioned over the expander to determine the correct dimension, border outline and length of the required flap. When using expanded skin, it may be safer to design the flap a few millimeters larger than the template to make up for recoil. 9. When ready for transfer, the flap is incised. The expander is removed with its port and a full thickness flap moved to the donor site. The fibrous rind which forms over the frontal bone, along the periphery of the capsule, will spontaneously resolve. It is often recontoured by excising the excess scar with an electrocautery to smooth the bony forehead. To allow easy transposition of the flap and proper length, the flap must be elevated across the supraorbital rim, opening and transecting the capsule at the flap’s base. The dissection is continued over the supraorbital rim towards the medial canthus. The entire expander capsule, with its contracting myofibroblasts, is routinely excised. 10. Frightening elastic shrinkage of the flap occurs on elevation of the expanded skin from the surface of the expander. Fortunately, the flap stretches back to its initial expanded dimensions when sutured to the nasal inset. However, a strong support framework is needed to prevent late flap recoil and skin contraction. 11. During the intermediate operation, if a significant scar lies within the expanded flap’s territory, the skin can be elevated as a bipedicle, extending from the brow
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Chapter • 8 • The Basics, Old Scars, Previous Forehead Flaps, Delay and Expansion
to the nasal columellar and rim. This maintains the maximum blood supply when contouring the underlying soft tissue or modifying the cartilage support.
General Guidelines to Protect and Repair the Forehead Donor Site 1. 2. 3. 4.
5.
A Figure 8–15
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Routinely use the vertical paramedian forehead flap design. Allow any gap within the superior forehead, which cannot be closed primarily, to heal secondarily. Revise the forehead scar secondarily, if necessary. In most circumstances after flap harvest, the defect which remains after harvest lies within the superior forehead. The inferior forehead donor, after transposition of its narrow 1.2–1.5 cm pedicle, can be closed primarily at transfer. Later, at pedicle division, most of the excess proximal pedicle is discarded. Only its most inferior aspect is replaced as a small inverted ‘V’ to restore the medial eyebrow. The remnant will simulate the frown crease. Occasionally, if the defect extends high onto the radix or its width extends laterally towards each medial canthus, the inferior forehead cannot be closed at the time of initial flap transfer. A gap remains in the inferior forehead (as well as the superior forehead) which cannot be closed primarily, even after advancement of the residual adjacent forehead skin. It is left open or temporarily skin grafted. At pedicle division, the unused proximal pedicle is returned to the donor site. An
B
General Guidelines to Protect and Repair the Forehead Donor Site
area of secondary healing (or a temporary skin graft) is excised and the unused proximal skin base, with medial eyebrow hair, is returned to the inferior forehead. The superior gap higher under the hairline is allowed to heal secondarily. After multiple failed repairs, a third forehead flap was harvested in this patient (Figure 8–15). The size and height of the defect and donor availability precluded primary
C
D
E
F
Figure 8–15, Continued
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Chapter • 8 • The Basics, Old Scars, Previous Forehead Flaps, Delay and Expansion
closure of the inferior forehead at transfer. The donor site was left open, initially. At pedicle division, the unused proximal portion of the flap was returned to the donor site to facilitate closure and restore the medial brow. The residual superior aspect of the defect was left to heal secondarily. 6.
7.
8. 9.
Consider pre-expansion of the flap but only when needed to increase the length or width of the available forehead. This is performed to construct a nose. It is not done to ease donor closure. Consider expansion of the forehead skin adjacent to the forehead flap. This is ordinarily performed after flap transfer to ease repair of the forehead defect which remains after flap harvest. This is rarely needed but remains an option. The nose must come first and the forehead second! Build the nose. Later expand the residual forehead to improve the donor site. Rarely, skin graft the residual gap which remains after forehead flap transfer. Rarely, resurface the entire forehead unit with a full-thickness skin graft. A tight shiny skin graft can simulate the expected tight shiny forehead unit. The skin graft border scars lay hidden in the junction between units and are not distracting.
In this patient (Figure 8–16), extensive recurrent basal cell carcinoma necessitated a total nasal amputation after a prior reconstruction which had resurfaced the nose with an oblique median forehead flap. The old donor site had been closed with a thigh skin graft. A second nasal repair was planned using a free radial forearm flap for lining, rib grafts for support, and a right paramedian forehead flap for total nasal resurfacing. Complica-
A Figure 8–16
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B
General Guidelines to Protect and Repair the Forehead Donor Site
tions, discussed in chapter 21, required the harvest of a third forehead flap. At the time of pedicle division, the forehead was significantly distorted by the old thigh split thickness skin graft and extensive areas of secondary healing. Supra-clavicular skin was pre-expanded. Scar and old skin graft were excised within the forehead unit. The forehead donor site was grafted with full-thickness skin as a complete unit (Figure 8–17).
A
B
C
D
Figure 8–17
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Chapter • 8 • The Basics, Old Scars, Previous Forehead Flaps, Delay and Expansion
E
Figure 8–17, Continued
The appearance of the forehead is relatively good after total unit grafting. The expected tight shiny and relatively uniform character of the skin graft replicates the smooth shiny tight character of the normal forehead. The graft’s border scars lay relatively hidden along the periphery of the unit adjacent to the hair line, the eyebrows, and the junction of the medial and lateral forehead subunits along the temporal creast. The forehead is a peripheral unit of lesser priority.
Guidelines for the Excessively Short Forehead (Less Than Three to Four Centimeters) 1.
2. 3.
Extend the design into the hairline. Accept hair on the nose. Shave, pluck, depilate, laser, or destroy the subdermal hair bulbs by excision and coagulation, secondarily. Lower the flap pivot point by extending its base across the eyebrow towards the medial canthus. This effectively lengthens the flap and improves its reach. Rarely, expand the available height of forehead tissues by pre-expansion of the donor site.
Remember the nose is the primary concern. A good nose with a few hairs is acceptable to patients — a bad nose without hair is a failure. 268
Guidelines for Harvesting Multiple Forehead Flaps
Guidelines for Harvesting Multiple Forehead Flaps 1. 2. 3. 4.
Check the position and length of old scars. Determine the available forehead surface versus the recipient requirement. Consider use of the contralateral pedicle. Use a full-thickness forehead flap to increase vascular safety when old scars or past dissection may have interfered with the normal blood supply. 5. Delay the flap across an old scar, if one is present or if the pedicle is suspected of having been injured during previous surgery. 6. Consider tissue expansion, if the available forehead surface seems inadequate. 7. Consider using a non-paramedian forehead flap design based on other intact axial vessels (Scalping or Sickle flap). 8. If the donor site cannot be closed primarily under the hairline, allow any residual gap to heal secondarily. 9. If the inferior forehead cannot be closed primarily due to the size and location of the nasal defect, return the unused proximal pedicle to the forehead at its division to facilitate its closure and the appearance of the eyebrow. 10. In extreme circumstances, when the forehead has been extensively destroyed by previous injury or multiple forehead flap harvests, excise scar and residual skin within the unit and resurface the entire forehead with a one-piece full-thickness skin graft, obtained after expansion of supraclavicular skin.
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