World J. Surg. 13, 454--464, 1989

World Journal of Surgery 9 1989 by ~he Soci~t~ lntemadonaie de Chirurgie

The Contribution of Microsurgical Reconstruction to Craniofacial Surgery Neil Ford Jones, M.A., F.R.C.S. Division of Plastic and Reconstructive Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania, U.S.A.

Craniofacial surgery has revolutionized the surgical treatment of congenital anomalies affecting the facial and cranial skeleton. Similar techniques have since been used in the reconstruction of patients with extensive craniofacial injuries and following craniofacial resection of tumors involving the midface. The application of microsurgical free flaps to some of these craniofacial problems is another significant advance. Microsurgical transfer of deepithelialized skin flaps or omentum will allow the augmentation of soft tissue contour defects of the face in patients with hemifacial microsomia and Romberg's progressive facial hemiatrophy. Following craniofacial resection of extensive tumors of the midface, microsurgical free flaps and vascularized bone grafts will provide soft tissue coverage and, occasionally, both bone and soft tissue composite reconstruction of the resultant defect. Finally, iotracranial infection, following craniofacial surgery and neurosurgical excision of tumors involving the skull base, may be effectively prevented by separation of the dura from the nasopharynx by microsurgical transfer of free muscle flaps and omentum.

Craniofacial surgery originated to reconstruct rare congenital deformities affecting the cranial and facial bone skeleton. After extensive exposure of the facial skeleton from below and the cranial base from above, intracranial, extracranial, and facial osteotomies allow 3-dimensional (3-D) repositioning of the cranial and facial skeleton. With progressive refinements in technique, the exposures and osteotomies developed in the treatment of congenital craniofacial deformities have been applied to the reconstruction of patients with severe craniofacial injuries and to resection of extensive tumors involving the face and skull. Microsurgery, another subspecialty of plastic and reconstructive surgery, is a technique in which a segment of skin, muscle, bone, or composite tissue is isolated on a pedicle consisting of an inflow artery and outflow vein. After completely detaching the tissue from its donor site, it may be transferred to a recipient site with immediate restoration of its nutrient blood supply by mierovascular anastomoses of the vascular pedicle to recipient vessels in the vicinity of the defect to be reconstructed. With the introduction of more reliable donor flaps, the success rate of microsurgical free tissue transfers is approximately 95% in centers undertaking a large volume of this surgery. The technique allows the transfer of large areas of single or composite Reprint requests: Neil Ford Jones, M.A., F.R.C.S., Division of Plastic and Reconstructive Surgery, University of Pittsburgh, 1117 Scaife Hall, Pittsburgh, Pennsylvania 15261, U.S.A.

tissues for reconstruction without being restricted by the pedicle of an axial pattern flap or myocutaneous flap. In the case of patients undergoing tumor resection, it allows early administration of radiation therapy. The obvious disadvantages of microsurgery are the prolonged operating time and the potential total loss of the transferred tissue should thrombosis of either the arterial or venous anastomosis occur. Microsurgical free tissue transfer does have some definite applications for some of the patients undergoing craniofacial bony repositioning or craniofacial tumor resections, either during the same procedure as the craniofacial surgery or at a separate second stage. Some of these applications of microsurgery to craniofacial surgery are already well-established, others continue to evolve with progress in the 2 subspecialties: (a) Augmentation of the soft tissue facial contour deformity or hypoplasia in Romberg's hemifacial atrophy and hemifacial microsomia; (b) Soft tissue coverage and composite reconstruction of patients undergoing craniofacial resection of extensive tumors involving the face and skull; (c) Prevention of intracranial infection in patients undergoing extensive craniofacial surgery or following resection of tumors involving the skull base. Augmentation of Soft Tissue Contour Defects and Hypoplasia of the Face

Underdevelopment or hypoplasia of the soft tissues of the face may be a component of some congenital anomalies such as hemifacial microsomia or occur later in childhood and adolescence due to Romberg's progressive facial hemiatrophy or due to the late sequelae of radiation. Hemifacial microsomia is a congenital anomaly in which varying degrees of hypoplasia affect the structures derived from the first and second branchial arches. Consequently, these patients may exhibit unilateral or bilateral underdevelopment of the external ear, middle ear, mandible, zygoma, maxilla, temporal bone, facial muscles, muscles of mastication and palatal muscles, tongue, and parotid gland. The underlying facial bony skeleton can be successfully corrected by varying combinations of mandibular, maxillary, and orbital osteotomies and onlay rib grafting; however, even though satisfactory skeletal symmetry can be achieved by these craniofacial techniques, the facial soft tissues may still remain hypoplastic with a contour concavity on

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Fig. IA. Twenty-three-year-old man with Romberg's hemifacial atrophy affecting the right side of his face, which had not progressed for the previous 2 years. B, C. Facial moulage of the soft tissue contour defect of the right side of the face. D, E. Operative markings of a right scapular skin flap based on the circumflex scapular artery and vein. The isolated scapular flap is shown prior to deepithelialization. (Fig. 1 continued on next page.)

the affected side. This soft tissue hypoplasia has been conventionally addressed by implantation of alloplastic materials or by cartilage and dermal fat grafts. These procedures may be

associated with infection, secondary scarring, changes in position of the implant, and an unpredictable rate of resorption. Microsurgical transfer of a segment of vascularized omentum

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Fig. 1. Continued. F. Same patient as in A two years following free deepithelialized scapular flap augmentation of the right side of the face with anastomosis of the circumflex scapular artery and vein to the facial artery and vein. or a deepithelialized skin flap has now become the method of choice for secondary augmentation of the facial soft tissue deformity following primary craniofacial correction of the bony abnormalities in hemifacial microsomia. In addition to correcting the soft tissue deficiency, primary microsurgery may also facilitate mandibular bony repositioning when soft tissue cover is considered to be inadequate. Occasionally, therefore, both the craniofacial bony repositioning and the microsurgical augmentation are performed at the same procedure. Progressive facial hemiatrophy or Romberg's disease is a condition of unknown etiology that results in atrophy of the skin and subcutaneous tissues of the face, usually occurring in adolescents or young adults (Fig. IA). The overlying skin, the underlying facial muscles, and, occasionally, the bones of the face and skull may all become atrophied, producing the characteristic "coup de sabre" appearance. The atrophy is usually unilateral and progressive but may stop at any age. Just as in hemifacial microsomia, conventional treatment of progressive hemifacial atrophy has been performed using liquid silicone injections or by bone, cartilage, and dermal fat grafts, but with unpredictable degrees of resorption. Microsurgical reconstruction using free omentum or free deepithelialized skin flaps has evolved as the most effective form of reconstruction for these patients, Microsurgical transfer of a dermal-fat flap from the lower abdomen based on the superficial epigastric artery and vein was first advocated by Antia and Buch in 1971 [1, 2]. With the development of axial pattern skin flaps, the deltopectoral flap and groin flap, these 2 flaps were then used as deepithelialized free flaps for filling out the contour deformity in patients with hemifacial microsomia and progressive facial hemiatrophy [3-

13]. Both the free deltopectoral flap based on perforating branches from the internal mammary artery and the free groin flap based on the superficial circumflex lilac artery have short, sometimes inconsistent, vascular pedicles and these donor sites were eventually superceded by more reliable flaps. Microsurgical transfer of a segment of omentum based on the right gastroepiploic artery and vein was first described by Harii in 1978 for treatment of progressive facial hemiatrophy [14]. Many other authors have since reported the advantages of using omentum as the donor tissue [15-20]. The omentum may be layered upon itself to build up its thickness. Separate tongues of omentum may be dissected based on the multiple arteriovenous arcades and positioned in separate pockets in the periorbital area, cheek and chin regions. These separate pockets filled by vascularized omentum may prevent subsequent downward migration of the transferred tissue due to the effects of gravity. Obviously, harvesting of the omentum requires an intraabdominal procedure, but these patients are usually young and have not had previous abdominal procedures that may have resulted in intraabdominal adhesions. Other donor sites have also been used including a deepithelialized dorsalis pedis flap [11] based on the dorsalis pedis artery and vein, the deepithelialized tensor fascia lata flap [21] based on the lateral circumflex femoral artery and vein, free muscle flaps such as the rectus abdominis muscle [22] supplied by the deep inferior epigastric artery and vein, and the latissimus dorsi muscle flap [10J based on the thoracodorsal artery and vein (Table 1). Free muscle flaps have not gained acceptance as preferred donor sites for reconstruction of soft tissue contour defects of the face since, after division of their motor nerves, the rate of atrophy is unpredictable. Consequently, even with overcorrection, the subsequent

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Table 1. Microsurgical donor sites for soft tissue augmentation in hemifacial microsomia and progressive hemifacial atropy. Deepithelialized skin flap Deltopectoral flap Groin flap Scapular/parascapular flap Superficial inferior epigastric artery flap Deepithelialized myocutaneous flap Tenor fascia lata MuscLe flaps Rectus abdominis Latissimus dorsi Vascularized omental transfer

muscle atrophy may eventually result in undercorrection of the soft tissue defect. The deepithelialized scapular/parascapular flap has also evolved to rival the vascularized omentum as the flap of choice for patients with hemifacial microsomia and progressive facial hemiatrophy requiring soft tissue augmentation. The scapular and parascapular flaps provide large areas of skin and soft tissue from the upper back supplied by the circumflex scapular artery and 2 venae commitantes [10, 23]. The donor site can usually be closed primarily, leaving a widened scar running transversely or obliquely across the upper back. In patients with Romberg's progressive facial hemiatrophy, timing of soft tissue augmentation by microsurgery remains controversial. It is usually preferable to wait until the soft tissue deformity has stopped progressing and the facial deformity has been stable for 2 years. Obviously, psychological factors may induce the surgeon to consider microsurgical augmentation at an earlier stage and there is some anecdotal evidence that transfer of tissue with its own independent blood supply into the area affected by Romberg's disease may retard the further degeneration of the soft tissues. In hemifacial microsomia, bony repositioning is carried out if necessary by the craniofacial team at the appropriate age and this is then followed by a soft tissue augmentation procedure by the microsurgical team 3-6 months later [4, 7, 10, 18, 21]. In patients with hemifacial microsomia or progressive facial hemiatrophy, a moulage of the soft tissue defect can be made by the facial prosthetist or it can be reformatted from 3-D computed tomography scans. This allows the surgeon to estimate the volume and areas of the face that require augmentation (Fig. 1B, C). This preoperative planning and the patient's own preference obviously dictate whether omentum or deepithelialized scapular skin provides the donor tissue. In either case, surgery is usually performed with 2 teams, 1 team isolating and harvesting the omentum or free scapular flap, and 1 team isolating recipient vessels in the head and neck suitable for microsurgical anastomoses--usually the superficial temporal artery and vein or the facial artery and vein. The skin of the involved side of the face is elevated by a preauricular incision extending into one of the neck skin creases paralleling the body of the mandible. In progressive facial hemiatrophy, the skin is very thin, but once elevated from the underlying facial muscles, there have been no problems with subsequent necrosis unless excessive tension is used during closure of the incisions. If omentum is to be used as the donor tissue, distinct pockets can be separated by fibrous septa to prevent future downward shift of the transferred tissue due to the effects of gravity. Both the

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omentum, based on the right gastroepiploic vessels, and the scapular or parascapular flap, based on the circumflex scapular vessels (Fig. 1D, E), have long pedicles allowing the microsurgical anastomoses to be easily performed to the superficial temporal or facial vessels. After transfer of the omentum or scapular tissue, the tissue can be partially divided into 3 separate tongues, one to augment the area above a line drawn from the tragus to the lateral canthus of the eye, one to augment the cheek, and one to augment the area beneath a line drawn from the tragus to the lateral oral commissure. If the scapular flap is used, the skin is deepithelialized using either a drum dermatome or a scalpel. The flap is positioned with its dermal surface deep so that sculpturing and feathering of the subcutaneous fat can be performed using the sterilized moulage as a template. Microsurgical anastomoses are then completed using either 10/0 or 9/0 sutures in an end-to-end fashion. Once the viability of the revascularized omentum or scapular flap has been confirmed, the transferred tissue is placed in its desired position. The omentum can be layered upon itself to build up bulk. Gravitational descent can be prevented either by placing islands of omentum into separate skin pockets or by multiple suture fixation of the omentum to the underlying facial muscle fascia. With the deepithelialized scapular flap, the deepithelialized surface is placed deep and nonabsorbable sutures used to fix this dermal layer to the periosteum overlying the zygomatic arch, again to prevent subsequent inferior displacement. The skin is closed over the transferred tissue, leaving a small elliptical area of the free omentum or free scapular flap exposed in the region of the angle of the mandible. This is done for several reasons. Primary closure, especially in cases of progressive facial hemiatrophy, may lead to necrosis of the thin atrophic cheek skin, but even more importantly, primary closure may sometimes produce excessive compression, especially of the outflow vein, and lead to subsequent thrombosis and loss of the transferred tissue. A small skin graft can be placed over the exposed tissue to allow postoperative monitoring of the free tissue transfer which would otherwise be very difficult since these microsurgically transferred tissues are completely "buried" once the incisions are closed. If a deepithelialized scapular flap has been used and the dermal surface has been placed superficial immediately beneath the skin of the cheek, a small ellipse of skin of the scapular flap can be used in this same area to act as an external monitor of the vascularity of the underlying fat tissue. The skin graft or skin ellipse can then be excised in a very minor procedure several months later and this is sometimes combined with any revisions that are necessary to reduce minor degrees of overcorrection of the deformity. In long-term follow-up, resorption of the transferred omentum or deepithelialized skin flaps has not been a problem (Fig. IF). Gravitational migration of the tissue does sometimes lead to a bulge over the body of the mandible and may require minor repositioning procedures. Microsurgical Reconstruction following Craniofacial Resection of Extensive Tumors of the Midface

Patients occasionally present with extensive basal cell or squamous cell carcinomas involving the middle third of the face which, in addition to their peripheral extension, may also invade the ethmoid sinuses, cribriform plate, and dura and

458 frontal lobes [24]. Carcinomas of the maxillary sinus may also invade superiorly and externally. These tumors usually grow to this extensive size because of patient neglect or failure and delay in seeking medical attention. Recurrent tumors may also attain large proportions following failure of primary surgical or radiotherapy treatment. Based on experience gained from craniofacial surgery, a simultaneous facial and intracranial approach to these tumors by a multidisciplinary team of neurosurgeons, ENT (ear, nose, throat) surgeons, and plastic surgeons allows direct assessment of the extent of these tumors and permits an en bloc resection [25, 26]. Craniofacial resection of such tumors results in complex 3-D defects that involve both an intraoral palatal defect combined with a soft tissue defect of the middle third of the face with a maxillectomy and orbital exenteration. Hemimaxillectomy defects are traditionally reconstructed using a split thickness skin graft held in position by a stent. After healing of the skin grafts has been achieved, an obturator prosthesis is fitted; however, with more radical resection of the orbital roof and floor of the anterior cranial fossa, the dura or dural graft overlying the frontal lobe communicates directly with the nasopharynx and oral cavity. Consequently, it becomes imperative to separate the dura from the nasopharynx and oral cavity by well-vascularized tissue to prevent cerebrospinal fluid leakage, ascending infection, and resultant meningitis. Local flaps such as the glabellar flap and the galeal-frontalis myofascial flap [27, 28] can be reliably used to separate small areas of communication, but in patients with extensive communication between the dura and nasopharynx and oral cavity, a galeal flap in conjunction with a split thickness skin graft and obturator prosthesis may be less reliable. The area of tissue available and limited arc of rotation restricts the use of pedicled deltopectoral skin flaps and pectorails major and latissimus dorsi myocutaneous flaps. Furthermore, multistage operations may delay postoperative radiotherapy. Microsurgical free flap reconstruction of these complex 3-D defects may be the ideal solution in these circumstances. The obvious danger inherent with immediate microsurgical reconstruction following craniofacial tumor resection is that, first, positive margins may be discovered several days later when permanent histological sections become available, despite clear margins on initial frozen sections. Second, depending on the biological behavior of the tumor, the incidence of local recurrences may be relatively high. Such a recurrence developing underneath a free flap may be difficult to detect compared with a recurrence becoming readily apparent beneath a split thickness skin graft. With delay in diagnosis, such recurrences may become inoperable and, for these reasons, primary closure Of the wound using a simple skin graft remains the standard management [28]. Complex flap reconstruction can then be performed secondarily when the chances of recurrence have receded. Immediate microsurgical reconstruction may be indicated for several reasons. Preoperative evaluation of these tumors has been revolutionized by progress in compute d tomography and magnetic resonance imaging (MRI), which have allowed improved anatomical definition of the extracranial and intracranial extension of these tumors. Three-dimensional reformatting can be used to produce a spatial display of the excision required to encompass the tumor. Multiple frozen sections of every margin of the resection can be examined by a pathologist present

World J. Surg. Vo|. 13, No. 4, July/Aug. 1989 during the operation. Immediate reconstruction is only performed if all the margins can be confidently assessed as being free of tumor. Finally, many patients have previously undergone multiple attempts at surgical excision and a final radical resection may result in such an extensive defect or communication between the dura and the nasopharynx and oral cavity that split thickness skin grafts and other simpler methods of reconstruction cannot be utilized (Fig. 2A, B). Immediate microsurgical reconstruction [29] may, in these circumstances, allow a final attempt at curative resection or, in some cases, allow palliative resection to preclude further intractable pain. Various donor sites have been advocated for free flap reconstruction following craniofacial tumor resection, including the tensor fascia lata [30], rectus abdominis [31-33] and latissimus dorsi musculocutaneous flaps [29, 34], and vascu!arized omental transfer [35]. The latissimus dorsi musculocutaneous flap has become our preferred flap for these defects. Two or even 3 separate skin paddles can be precisely located overlying the latissimus dorsi muscle after first measuring the dimensions of the palatal and external facial skin defects and the distance of these defects from the recipient vessels. One skin paddle is used to reconstruct the hemipalatal or total palatal defect, a second paddle is used to close the defect in the external facial skin, and a third smaller paddle is used to recreate the lateral mucosal wall of the nasopharynx if necessary. The latissimus dorsi muscle may be draped along the undersurface of the dura of the anterior cranial fossa and packed into the hemimaxillectomy or bilateral maxillectomy cavities. Because of the relatively high incidence of tumor recurrence, we have not attempted to perform primary bony reconstruction, but have utilized the free flaps to separate the nasal, oral, and cranial cavities to allow rapid restoration of oral feeding, intelligible speech, and early fitting of an external prosthesis (Fig. 2C, D). Patients have been followed with frequent CT or MRI scans to detect any early evidence of tumor recurrence. With increasing experience of the radiologist, it appears that it is possible to differentiate between tumor recurrence and the transferred muscle and subcutaneous tissues, thereby ameliorating the criticisms of immediate microsurgical reconstruction. Microsurgical Vascularized Bone Transfers for Craniofacial Reconstruction

Patients with severe craniofacial injuries usually due to highvelocity gunshot wounds or blast injuries and patients undergoing resection of extensive tumors involving the orbit and skull occasionally require simultaneous reconstruction of both the underlying facial bony skeleton and the overlying soft tissues. Traditionally, this has been achieved in multiple stages by first obtaining soft tissue coverage with pedicled axial pattern skin flaps or pedicled myocutaneous flaps followed by secondary conventional bone grafting using the rib or lilac crest as the donor site. Microsurgery has obvious applications in such patients with craniofacial injuries and following craniofacial tumor resections in 2 distinct ways. First, the incorporation of conventional rib and lilac crest bone grafts used to restore bony continuity of the craniofacial skeleton can be enhanced by coverage of these bone grafts by a microsurgical skin flap, muscle flap, or vascularized omental transfer. The improved vascularity of the soft tissue envelope provided by the micro-

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Fig. 2A, B. Radical resection of a recurrent squam0us cell carcinoma of the left maxillary sinus that had extended superiorly into the orbit and anterior and middle cranial fossa resulting in a defect consisting Of a dural graft overlying the left frontal and temporal lobes (D), an open sphen0id sinus (S) and lateral wall of the nasopharynx (N); and a defect in the oral mucosa and left hemiPalate (P). A free latissimus dorsi musculocutaneous flap was used for reconstruction. One skin paddle was used to close the defect in the oral mucosa and palate and a very small second paddle of skin was used to close the lateral wall of the nasopharynx. Sheets of split thickness skin graft were used to cover the external surface of the latissimus dorsi muscle. C, D. The patient showed no radiological signs of local recurrence 3 years postoperatively and has been fitted with a facial prosthesis held in position by glasses. Reprinted with permission of publisher [29]. surgical free flap should allow m o r e rapid revascularization of the b o n e grafts and so allow a single Stage reconstruction. This c o n c e p t is o b v i o u s l y important in those patients undergoing

craniofacial tumor resection following p r e o p e r a t i v e radiotherapy. The highly vascularized soft tissue c o v e r a g e provided by microvascular free flaps also allows postoperative adjuvant

460 Table 2. Microsurgical donor sites for vascularized bone transfers.

Rib Latissimus dorsi and serratus anterior muscle flaps Iliac Crest Deep circumflex lilac artery flap Scapula Scapular osteocutaneous flap Vascularized metatarsophalangeal joint transfer

radiotherapy to be utilized once incorporation of the bone grafts has occurred. Since the soft tissue defects associated with craniofacial injuries and craniofacial tumor resections are usually extensive, the 2 microsurgical flaps employed for cover of conventional bone grafts are either a free latissimus dorsi muscle flap surfaced with a split thickness skin graft or a free omental transfer, again surfaced with a split thickness skin graft [36]. Second, a segment of vascularized bone may be transferred by microsurgical techniques either alone or together with an overlying skin flap or musculocutaneous flap as a composite transfer (Table 2). Vascularized bone grafts have been proven to maintain the viability of the osteoblasts and osteocytes, resulting in rapid osteosynthesis and minimal resorption. It is especially indicated in devascularized areas due to trauma or previous irradiation, for extensive segments of bone loss due to trauma and osteomyelitis, and for the salvage of patients in whom conventional bone grafting has repeatedly failed due to resorption. Composite microsurgical transfer of the latissimus dorsi muscle, the serratus anterior muscle, and one or more underlying ribs all vascularized by the thoracodorsal artery and vein has been used to reconstruct bone and Soft tissue defects involving the orbits, zygoma, and maxilla [37]. The deep circumflex iliac artery flap described by Taylor and associates [38], providing a length of up to 14 cm of vascuiarized bone from the iliac crest together with an overlying paddle of groin skin, has revolutionized mandibular reconstruction following hemimandibulectomy for tumors involving the floor of the mouth and retromolar trigone or mandibular bone loss due to 0steoradionecrosis; however, mandibular reconstruction by vascularized bone grafting cannot reallY be considered to be craniofacial surgery. Iliac crest bone grafts vascularized by the deep circumflex iliac artery may, however, have occasional applications for reconstruction of bony defects of the maxilla [7], orbit, and frontal bones and for secondary reconstruction of patients with craniofacial injuries. The scapular flap may also be dissected as an osteocutaneous flap incorporating a t0-12 cm segment of the lateral border of the scapula and we have used this osteocutaneOus scapular flap to reconstruct composite defects of the orbit and maxilla [39] in secondary reconstruction following radical maxiliectomies. Finally, microvascular bone transfers are occasionally indicated for patients with congenital craniofacial anomalies such as hemifacial microsomia and acquired deformities of the ascending ramus of the mandible and temporomandibular joint secondary to trauma. A Vascularized iiiac crest bone transfer can be performed simultaneously with mandibular osteotomies to elongate the ascending ramus Of the mandible in patients with hemifacial microsomia. We have utilized a composite microvascular transfer of both vascularized bone and vascularized joint to reconstruct the ascending ramus and restore mobility to the

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temporomandibular joint of patients with hemifacial microsomia and ankylosis of the temporomandibular joint due to previous trauma or infection (Fig. 3A) [40, 41]. The metatarsal a n d proximal phalanx of the second toe together with the intervening metatarsophalangeal joint can be transferred as a composite microvascular transfer based on the dorsalis pedis artery and its continuation as the first dorsal metatarsal artery and the saphenous vein (Fig, 3B-D). The vascularized metatarsophalangeal joint has a greater axis of hyperextension than flexion and may be used to reconstitute the temporomandibular joint as a pure hinge joint with the vascularized bone of the second metatarsal used to elongate the ascending ramus of the mandible. Unlike conventional nonvascularized joint transfers, these vascularized joints maintain the viability of the chondrocytes in the articular cartilage and allow preservation of motion in the transferred joint (Fig. 3E, F). Prevention of Intracranial Infection by Microsurgical Free Tissue Transfer

In specialized craniofacial units performing a high volume of craniofacial surgery, the incidence of postoperative meningitis is very low [42-44]. Intracranial infection in congenital cases is due to a communication between the nasopharynx and an unrecognized tear in the dura of the anterior cranial fossa or a cerebrospinal fluid leak through a dural graft in this same area. This may be prevented by avoiding entry into the nasal cavity by stripping the mucoperiosteum of the nasal bones and displacing it inferiorly to allow the bony osteotomies to be performed or by transposition of a local flap of galea and frontalis fascia beneath the dura of the anterior cranial fossa to serve as a barrier between the contaminated nasopharynx and the dura [27]. In the frontofacial advancement procedure for craniofacial dysostoses, in addition to the potential contamination from the nasopharynx, the large area of dead space behind the frontal advancement segment also contributes to the higher incidence of infection in this procedure [45]. In young children, the expanding brain rapidly fills the extra-dural dead space, but in older Children and adults, contamination of this extra-dural dead space may result in an extra-dural abscess and possible osteomyelitis of the overlying frontal bone segment. The galeal frontalis myofascial flap elevated off the bicoronal scalp flap and vascularized by the supraorbital and supratrochlear arteries may be used both to obliterate the extra-dural dead space and also to separate the nasopharynx from the dura. Very infrequently, if the galeaI frontalis myofascial flap is not available or inadequate in size and volume, microsurgieal transfer of vascularized tissue has been used to obliterate the extra-dural dead space following frontofacial advancement. In such cases, microsurgical free tissue transfer is perfo/'med immediately following completion of the craniofacial bony repositioning. The latissimus dorsi muscle vascularized by the thoracodorsal vessels or a free omental transfer [44, 45] have been used very effectively in these circumstances with microsurgical anastomoses to the superficial temporal vessels. Vascularized omental transfers have also been utilized in established cases of frontal bone osteomyelitis after debridement of the necrotic bone sequestrum [46]. With refinements in surgical exposure and bony osteotomies, neurosurgeons and head and neck surgeons have increasingly

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Fig. 3A. Tomogram of a 21-year-old girl with ankylosis of her left temporomandibular joint due to severe trauma. There is complete loss of the temporomandibularjoint and collapse of the ascending ramus of the left hemimandible (arrows). Seven prior attempts at reconstruction had all been unsuccessful. B-D. A vascularized metatarsophalangeal joint transfer of her right second toe is shown isolated on the dorsalis pedis artery and its continuation, the first dorsal metatarsal artery, and the sapbenous vein. With the vascularized joint in hyperextension, the short proximal phalanx (P) was positioned in a drilled-out fossa in the temporal bone and the metatarsal (M) was used to reconstruct and elongate the ascending ramus of the mandible. E. Four years postoperatively, tomograms confirm that there has been no resorption of the vascularized bone of the proximal phalanx (P) or metatarsal (M) with a viable intercalated joint space (TMJ). F. The patient has satisfactory mobility of her reconstructed left temporomandibular joint without pain.

extended the applications of craniofacial surgery to permit exposure and resection of tumors involving the skull base. Just as with craniofacial anomalies, the major problem following surgical resection of skull base tumors is the close proximity of the paranasal sinuses and the nasopharynx to the exposed dura of the anterior and middle cranial fossae. Cerebrospinal fluid leakage through the site of a tenuous dural repair or a dural graft may allow infection to ascend from the nasopharynx or paranasal sinuses into the intradural space to produce fulminant

meningitis. This has been one of the main reasons why these skull base tumors have been previously deemed inoperable, Following resection of tumors involving the anterior and middle cranial base, small areas of communication between the nasopharynx and dura may be effectively separated using local flaps such as the galeal frontalis myofascial flap [27], the temporalis muscle flap, or the sternomastoid muscle flap; however, when there is wide-open communication between the nasopharynx, paranasal sinuses, and the dura, microsurgery

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art.

Fig. 4A, B. Following resection of a squamous cell carcinoma which eroded superiorly into the middle cranial fossa, a dural graft (D) overlying the temporal lobe freely communicates with a large defect in the lateral wall of the nasopharynx (N) and an open sphenoid sinus. C, D. Intraoperative photograph and diagramatic representation show a free rectus abdominis muscle flap anastomosed to a branch of the external carotid artery and to the stump of the internal jugular vein, being used to separate the dural graft overlying the temporal lobe from the nasopharynx and sphenoid sinus to prevent intracranial infection. provides a method for transferring vascularized tissue to act as a barrier between the nasopharynx and the cranial contents to prevent intracranial infection. We have used the free rectus abdominis muscle flap vascularized by the deep inferior epigastric artery and vein as the donor flap to prevent ascending infection following resection of

tumors involving the middle and posterior skull base [47]. Following resection of these tumors, the resultant defect usually consists of an opening in the posterior and lateral walls of the nasopharynx and an exposed sphenoid sinus, both of which are immediately adjacent to either a dural repair or a dural graft overlying the temporal lobe (Fig. 4A, B). The lower half of the

N.F. Jones: Microsurgical Reconstruction

rectus abdominis muscle may be harvested through a transverse or paramedian lower abdominal incision by a separate microsurgical team. The rectus muscle can then be sutured to the posterior and lateral borders of the defect in the nasopharynx and tongues of muscle used to obliterate the open sphenoid sinus. The remainder of the muscle is draped to cover any exposed dural repair or dural graft overlying the temporal lobe and posterior fossa or used to cover an exposed saphenous vein graft reconstruction of the internal carotid artery should this have required resection because of tumor involvement. The deep inferior epigastric artery is anastomosed end-to-end to one of the branches of the external carotid artery and the deep inferior epigastric veins are anastomosed end-to-side to the stump of the internal jugular vein (Fig. 4C, D). Obviously, such microsurgical reconstructions do require microsurgical expertise and prolong the operating time; however, in a series of over 30 patients, microsurgical free flaps have been extremely effective in preventing cerebrospinal fluid leakage and meningitis following resection of tumors involving the middle and posterior skull base, especially when these resections have resulted in extensive communication between the dura and the nasopharynx and paranasal sinuses. R~sum~

La chirurgie craniofaciale a rdvolutionn~ le traitement des malformations cong6nitales du squelette facial et crfinien. Des techniques semblables ont 6t6 utilis6es pour la reconstruction apr~s traumatismes 6tendus craniofaciaux et apr6s trisection de tumeurs craniofaciales de l'6tage moyen. Les techniques microchirurgicales constituent 6galement un important progr6s. Les techniques de la microchirurgie permettent de transf6rer des lambeaux cutan6s dds6pith~lialisEs ou des lambeaux d'dpiploon pour combler des d~fauts de parties molles chez les patients qui prdsentent une microsomie de l'h6miface et un syndrome de Romberg. Apr6s r6section 6tendue des tumeurs de l'6tage moyen de la face, les lambeaux libres composites ostdocutands et les lambeaux osseux vascularis6s permettent le reeouvrement cutan6, et 6ventuellement la reconstruction simultan6e du ddfect osseux et cutan6. Enfin, l'infection intracrgtnienne apr~s chirurgie cr~niofaciale et ex6r~se neurochirurgicale des tumeurs de la base du crane peut fitre pr6venue en s6parant la dure-m~re de l'oropharynx grgtce au transfert microchirurgical de lambeaux libres rnusculaires et d'6piploon. Resumen

La cirugfa craneofacial ha revolucionado el tratamiento quirtirgico de las anomalias cong6nitas que afectan al esqueleto facial y craneano. Tdcnicas quirtirgicas similares ban sido utilizadas para la reconstrucci6n en pacientes con lesiones craneofaciales extensas y e n aquellos con defectos consecutivos a la resecci6n de tumores de la parte media de la cara. La aplicaci6n de colgajos libres obtenidos por microcirugfa a la soluci6n de este tipo de problemas es otro avance significativo. La transferencia microquirtirgica de colgajos desepiteliolizados de piel o de epipl6n permite corregir defectos de contorno de los tejidos blandos de la cara en pacientes con microsomia hemifacial y con hemiatrofia facial progresiva de Romberg. Despu6s de extensas resecciones craneofaciales de tumores de

463

la parte media de la cara, los colgajos libres microquirtirgicos y los injertos 6seos vascularizados proveen cubrimiento de tejidos blandos y, ocasionalmente, permiten la reconstrucci6n compuesta, 6sea y de tejidos blandos, del defecto resultante. Pot tiltimo, la infecci6n intracraneana que ocurre como consecuencia de cirugia craneofacial y de la resecci6n neuroquirtirgica de tumores de la base del crrlneo, puede set prevenida en forma efectiva mediante la separaci6n de la dura de la nasofaringe con la transferencia microquirtirgica de colgajos libres de mtisculo y de epipl6n. References

1. Antia, N.H., Buch, V.I.: Transfer of an abdominal dermo-fat graft by direct anastomosis of blood vessels. Br. J. Plast. Surg. 24:15, 1971 2. Wells, J.H., Edgerton, M.T.: Correction of severe hemifacial atrophy with a free dermis fat flap from the lower abdomen. Plast. Reconst. Surg. 59:223, 1977 3. Fujino, T., Tanino, R., Sugimoto, C.: Microvascular transfer of free deltopectoral dermal fat flap. Plast. Reconst. Surg. 55:428, 1975 4. Fujino, T., Tanino, R., Sugimoto, C., Nakajima, H., Kiyoizumi, T.: An l l-year follow-up case of facial hemiatrophy treated by combined approaches of craniofacial and microvascular surgeries. Keio J. Med. 34:123, 1985 5. Anderl, H.: Free vascularized groin fat flap in hypoplasia and hemiatrophy of the face. J. Maxillofac. Surg. 7:327, 1979 6. David, D.J., Tan, E.: A de-epithelialized free groin flap for facial contour restoration. J. Maxillofac. Surg. 6:249, 1978 7. David, D.J., Tan, E.: Microvascular surgery in maxillofacial reconstruction. Ann. Acad. Med. 8:481, 1979 8. Harashina, T., Nakajima, T., Yoshimura, Y.: A free groin flap reconstruction in progressive facial hemiatrophy. Br. J. Plast. Surg. 30:14, 1977 9. Harashina, T., Fujino, T.: Reconstruction in Romberg's disease with free groin flap. Ann. Plast. Surg. 7:289, 1981 10. Hemmer, K.M., Marsh, J.L., Clement, R.W.: Pediatric facial free flaps. J. Reconstr. Microsurg. 3:221, 1987 11. O'Brien, B.M.C., Russell, R.C., Morrison, W.A., Sully, L.: Buried microvascular free flaps for reconstruction of soft tissue defects. Plast. Reconstr. Surg. 68:712, 1981 12. Shintomi, Y., Ohura, T., Honda, K., Iida, K.: The reconstruction of progressive facial hemiatrophy by free vascularized dermis-fat flaps. Br. J. Plast. Surg. 34:398, 1981 13. Williams, H.B., Crepeau, R.J.: Free dermal fat flaps to the face. Ann. Plast. Surg. 3:1, 1979 14. Harii, K.: Free omental transfer. Trans. Sixth Int. Congr. Plast. Reconstr. Surg., Paris, 1976, p. 61 15. Harii, K.: Clinical application of free omental flap transfer. Clin. Plast. Surg. 5:273, 1978 16. Jurkiewicz, M.J., Nahai, F.M.: The omentum: Its use as a free vascularized graft for reconstruction of the head and neck. Ann. Surg. 195:756, 1982 17. Jurkiewicz, M.J., Nahai, F.M.: The use of free revascularized grafts in the amelioration of hemifacial atrophy. Plast. Reconstr. Surg. 76:44, 1985 18. Upton, J., Mulliken, J.B., Hicks, P.D., Murray, J.E.: Restoration of facial contour using free vascularized omental transfer. Plast. Reconstr. Surg. 66:560, 1980 19. Wallace, J.G., Schneider, W.J., Brown, R.G., Nahai, F.M.: Reconstruction of hemifacial atrophy with a free flap of omentum. Br. J. Plast. Surg. 32:15, 1979 20. Walkinshaw, M., Caffee, H.H., Wolfe, S.A.: Vascularized omenturn for facial contour restoration. Ann. Plast. Surg. 10:292, 1983 21. LaRossa, D., Whitaker, L., Dabb, R., Mellissinos, E.: The use of microvascular free flaps for soft tissue augmentation of the face in children with hemifacial microsomia. Cleft Palate J. 17:138, 1980 22. Fisher~ J.: Microvascular reconstruction in the head and neck. Mayo Clin. Proc. 61:451, 1986

464 23. Serra, J.M., Muirragui, A., Tadjalli, H.: The circumflex scapular flap for reconstruction of mandibulofacial atrophy. J. Reconstr. Microsurg. 1:263, 1985 24. Savage, R.C.: Orbital exenteration and reconstruction for massive basal cell and squamous cell carcinoma of cutaneous origin. Ann. Plast. Surg. 10:458, 1983 25. Jackson, I.T., Laws, E.R., Martin, R.D.: A craniofacial approach to advanced recurrent cancer of the central face. Head Neck Surg. 5:474, 1983 26. Sypert, G.W., Habal, M.B.: Combined cranio-orbital surgery for extensive malignant neoplasms of the orbit. Neurosurg. 2:8, 1978 27. Jackson, I.T., Adham, M.N., Marsh, W.R.: Use of the galeal frontalis myofascial flap in craniofacial surgery. Plast. Reconstr. Surg. 77:905, 1986 28. Jackson, I.T.: Invited discussion of "Free rectus abdominis muscle flap reconstruction of the middle and posterior cranial base." Plast. Reconstr. Surg. 78:478, 1986 29. Jones, N.F., Swartz, W.M., Hardesty, R.A., Ramasastry, S.S., Heckler, F . R , Newton, E.D.: Extensive and complex defects of the scalp, middle third of the face and palate: The role of microsurgical reconstruction. Plast. Reconstr. Surg. 82:937, 1988 30. Bridger, G.P., Baldwin, M., Gonski, A.: Craniofacial resection for paranasal sinus with free flap repair. Aust. N . Z . J . Surg. 56:843, 1986 31. Chicarilli, Z.N., Davey, L.M.: Rectus abdominis myocutaneous free flap reconstruction following a cranio-orbital-maxillary resection for neurofibrosarcoma. Plast. Reconstr. Surg. 80:726, 1987 32. Maruyama, Y., Osafune, H.: Free vertical abdominal fasciocutaneous flap. Br. J. Plast. Surg. 40:27, 1987 33. Miyamoto, Y., Harada, K., Kodama, Y., Takahashi, H., Okano, S.: Cranial coverage involving scalp, bone and dura using free inferior epigastric flap. Br. J. Plast. Surg. 39:483, 1986 34. Baker, S.R.: Closure of large orbital-maxillary defects with free latissimus dorsi myocutaneous flaps. Head Neck Surg. 6:828, 1984

World J. Surg. Vol. 13, No. 4, July/Aug. 1989 35. Arnold, P.G., Irons, G.B.: The greater omentum: Extensions in transposition and free transfer. Plast. Reconstr. Surg. 67:169, 1981 36. Arnold, P.G., Irons, G.B.: One-stage reconstruction of massive craniofaciai defect with gastro-omentaI free flap. Ann. Plast. Surg. 6:26, 1981 37. Richards, M.A.: Free composite reconstruction of a complex craniofacial defect. Aust. N.Z.J. Surg. 57:129, 1987 38. Taylor, G.I., Townsend, P., Corlett, R.: Superiority of the deep circumflex iliac vessels as the supply for free groin flaps. Plast. Reconstr. Surg. 64:745, 1979 39. Swartz, W.M., Banis, J.C., Newton, E.D., Ramasastry, S.S., Jones, N.F,. Acland, R.: The osteocutaneous scapular flap for mandibular and maxillary reconstruction. Plast. Reconstr. Surg. 77:530, 1986 40. Dattilo, D.J., Granick, M.S., Sotereanos, G.S.: Free vascularized whole joint transplant for reconstruction of the temporomandibular joint. J. Oral Maxillofac. Surg. 44:227, 1986 41. Ting, Z., Chang, T., Wang, T., Wang, W., Feng, S.: Vascular metatarsophalangeal to ankylosed temporomandibular joint replacement. Ann. Plast. Surg. 15:497, 1985 42. Whitaker, L.A., Broennle, A.M., Kerr, L.P., Herlich, A.: Improvements in craniofacial reconstruction: Methods evolved in 235 consecutive patients. Plast. Reconstr. Surg. 65:561, 1980 43. Jackson, I.T.: Advances and innovations in craniofacial surgery. Plast. Surgical Nursing 5:22, 1985 44. David, D.J., Cooter, R.D.: Craniofacial infection in 10 years of transcranial surgery. Plast. Reconstr. Surg. 18:213, 1987 45. Jackson, I.T.: Infection following fronto-supraorbital advancement. Perspec. Plast. Surg. 1:93, 1987 46. Barrow, D.L., Nahai, F., Tindall, G.: The use of greater omentum vascularized free flaps for neurosurgical disorders requiring reconstruction. J. Neurosurg. 60:305, 1984 47. Jones, N.F., Sekhar, L.M., Schramm, V.L.: Free rectus abdominis muscle flap reconstruction of the middle and posterior cranial base. Plast. Reconstr. Surg. 78:471, 1986