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Recent refinements of magnetic resonance angiography (MRA) allow imaging vessels as small as the septocutaneous perforators (< or = 1 to 2 mm diameter), but a Medline review reveals no report of septocutaneous vessel imaging for free flap surgery. Challenges in fibula free flap preparation include knowledge of: (1) tibioperoneal anatomy, (2) the positions of the perforator vessels on the peroneal artery and their course in the posterolateral intermuscular septum, and (3) the cutaneous distribution of the perforators. Questioning whether high-resolution MRA could image these, we studied the lower extremities of nine healthy volunteers. MRA demonstrated tibioperoneal anatomy in sufficient detail to exclude anatomic variants and significant peripheral vascular disease and showed septocutaneous perforators arising from the peroneal artery and coursing in the posterolateral intermuscular septum to the skin. High-resolution MRA provided anatomic and clinical information that conventionally has been impossible to obtain preoperatively or has required multiple tests, often of an invasive nature.

Five patterns of muscle circulation, based on studies of the vascular anatomy of muscle, are described. Clinical and experimental correlation of this classification is determined by the predictive value of the vascular pattern of each muscle currently useful in reconstructive surgery in regard to the following parameters: arc of rotation, skin territory, distally based flaps, microvascular composite tissue transplantation, and design of muscle-delay experimental models. This classification is designed to assist the surgeon both in choice and design of the muscle and musculocutaneous flap for its use in reconstructive surgery.

Background Although prolonged composite tissue allograft (CTA) survival is achievable in animals using immunosuppressive drugs, long-term immunosuppression of CTAs in the clinical setting may be unacceptable for most patients. The purpose of this study was to develop a model for reliable CTA tolerance induction in the adult rat across a major MHC mismatch without the need for long-term immunosuppression. Methods Mixed allogeneic chimeras were prepared by using rat strains with strong MHC incompatibility [WF (RT1Au), ACI (RT1Aa)] WF + ACI-->WF, n=23. The bone marrow (BM) of recipient animals was pretreated with low-dose irradiation (500-700 cGy), followed by reconstitution with a mixture of T cell-depleted syngeneic (WF) and allogeneic (ACI) cells. Additionally, the recipient animals received a single dose of anti-lymphocyte serum (10 mg) 5 days before bone marrow transplantation (BMT) and tacrolimus (1 mg/kg/day) from the day before BMT to 10 days post-BMT. Hindlimb transplants were performed 12 months after BMT. Five animals received a limb allograft irradiated (1000 cGy) just before transplantation. Rat chimeras were characterized (percentage of donor cells present within the bloodstream) by flow cytometry at 3 and 12 months after BM reconstitution and after hindlimb transplantation. Results Peripheral blood lymphocyte chimerism (WF/ACI) remained stable >12 months after BM reconstitution in 18/23 animals. Multi-lineage chimerism of both lymphoid and myeloid lineages was present, suggesting that engraftment of the pluripotent rat stem cell had occurred. In animals with donor chimerism >60% (n=18) no sign of limb rejection was present for the duration of the study. All animals with chimerism 60 days in 14/21 rats. Postoperative flow cytometry studies demonstrated stable chimerism in all animals studied (n=10). Five out of five animals with irradiated limb transplants showed no sign of GVHD at >100 days. Conclusions Stable mixed allogeneic chimerism can be achieved in a rat hindlimb model of composite tissue allotransplantation. Hindlimb allografts to mixed allogeneic chimeras exhibit prolonged, rejection-free survival. Partial functional return should be expected. The BM transplanted as part of the hindlimb allograft plays a role in the etiology of GVHD. Manipulating that BM before transplantation may influence the incidence of GVHD. This represents the first reliable rat hindlimb model demonstrating rejection-free CTA survival in an adult animal across a major MHC mismatch without the long-term need for immunosuppressive agents.

Patients with a giant congenital melanocytic nevus can develop melanotic tumors characterized by central nervous system involvement, termed leptomeningeal melanocytosis or neurocutaneous melanosis. Although symptomatic neurocutaneous melanosis is rare, we previously reported distinct magnetic resonance (MR) findings of T1 shortening, strongly suggestive of neurocutaneous melanosis, in 30 percent (6 of 20) of children with giant congenital melanocytic nevi who presented initially without neurological symptoms. The purpose of this study was to determine the incidence of neurocutaneous melanosis in high-risk patients and its long-term clinical significance. Magnetic resonance imaging was recommended for all 46 patients with "at-risk" giant congenital melanocytic nevi involving the skin overlying the dorsal spine or scalp. The clinical histories and follow-up of these patients were evaluated by retrospective chart review. Forty-two underwent MR imaging of the brain and 11 underwent additional MR scanning of the spinal cord. Abnormalities were identified in 14 of 43 MR studies, and 23 percent (n = 10) had T1 shortening indicative of melanotic rests within the brain or meninges. None had associated masses or leptomeningeal thickening. The most common areas of involvement in these 10 included the amygdala (n = 8), cerebellum (n = 5), and pons (n = 3). In the group of 11 patients with spinal MR scans, a tethered spinal cord was demonstrated in one. Additional abnormalities were detected by MR scanning, including a middle cranial fossa arachnoid cyst, a Chiari type I malformation, and a crescentic enhancement that subsequently resolved. Clinical follow-up averaging 5 years (range, 2 to 8 years) revealed that only one of the 46 patients evaluated developed neurological symptoms, manifested as developmental delay, hypotonia, and questionable seizures but no other signs of neurocutaneous melanosis. No patient has developed a cutaneous or central nervous system melanoma. Magnetic resonance findings of neurocutaneous melanosis are relatively common, even in asymptomatic children with giant congenital melanocytic nevi. Although these findings suggest an increased lifetime risk of central nervous system melanoma, they do not signify the eventual development of symptomatic neurocutaneous melanosis during childhood.

Objective To analyze a series of patients treated for recurrent or chronic abdominal wall hernias and determine a treatment protocol for defect reconstruction. Background Data Complex or recurrent abdominal wall defects may be the result of a failed prior attempt at closure, trauma, infection, radiation necrosis, or tumor resection. The use of prosthetic mesh as a fascial substitute or reinforcement has been widely reported. In wounds with unstable soft tissue coverage, however, the use of prosthetic mesh poses an increased risk for extrusion or infection, and vascularized autogenous tissue may be required to achieve herniorrhaphy and stable coverage. Methods Patients undergoing abdominal wall reconstruction for 106 recurrent or complex defects (104 patients) were retrospectively analyzed. For each patient, hernia etiology, size and location, average time present, technique of reconstruction, and postoperative results, including recurrence and complication rates, were reviewed. Patients were divided into two groups based on defect components: Type I defects with intact or stable skin coverage over hernia defect, and Type II defects with unstable or absent skin coverage over hernia defect. The defects were also assigned to one of the following zones based on primary defect location to assist in the selection and evaluation of their treatment: Zone 1A, upper midline; Zone IB, lower midline; Zone 2, upper quadrant; Zone 3, lower quadrant. Results A majority of the defects (68%) were incisional hernias. Of 50 Type I defects, 10 (20%) were repaired directly, 28 (56%) were repaired with mesh only, and 12 (24%) required flap reconstruction. For the 56 Type II defects reconstructed, flaps were used in the majority of patients (n = 48; 80%). The overall complication and recurrence rates for the series were 29% and 8%, respectively. Conclusions For Type I hernias with stable skin coverage, intraperitoneal placement of Prolene mesh is preferred, and has not been associated with visceral complications or failure of hernia repair. For Type II defects, the use of flaps is advisable, with tensor fascia lata representing the flap of choice, particularly in the lower abdomen. Rectus advancement procedures may be used for well-selected midline defects of either type. The concept of tissue expansion to increase both the fascial dimensions of the flap and zones safely reached by flap transposition is introduced. Overall failure is often is due to primary closure under tension, extraperitoneal placement of mesh, flap use for inappropriate zone, or technical error in flap use. With use of the proposed algorithm based on defect analysis and location, abdominal wall reconstruction has been achieved in 92% of patients with complex abdominal defects.

Results of earlier investigations have demonstrated impaired function of polymorph-nuclear cells (PMN) in previously irradiated tissue. This study was designed to examine the effect of local oxygen pressure (pO2) on neutrophil function in irradiated tissue. By choosing a pig model of irradiated and non-irradiated high perfusion wound environment (i.e. musculo-cutaneous (MC) flap) vs. a poor perfusion wound environment (i.e. random pattern (RP) skin flap), the effect of different pO2 levels on neutrophil phagocytosis and respiratory burst (H2O2 production) were measured at 6, 12, and 16 weeks after irradiation. In both kinds of irradiated flaps, pO2 levels and neutrophil function were significantly lower (RP

The role of wound debridement and flap coverage in treating pressure sores is clearly established. However, criteria and supportive clinical data for specific flap selection and the sequence of flaps for coverage of the ischium remain ill-defined. From 1979-1995, 114 consecutive patients underwent flap coverage of 139 ischial pressure sores. Preoperative risk factors, prior flap history, defect size, flap success, complication rates, and the length of hospitalization were retrospectively evaluated and compared for 112 flaps in 87 patients. Flap success was defined as a completely healed wound. Average follow-up was 10 months (range: 1 month-9 years). Overall, 83% (93/112) of the flaps healed. In the majority of cases (75%, 84/112), wound debridement and flap reconstruction was achieved in a single stage. However, there were significant differences in the healing rates among the various flaps used. The inferior gluteus maximus island flap and the inferior gluteal thigh flap had the highest success rates, 94% (32/34) and 93% (25/27), respectively, while the V-Y hamstring flap and the tensor fascia lata flap had the poorest healing rates, 58% (7/12) and 50% (6/12), respectively. Flap success was not significantly affected by the age of the patient or the prior number of flaps used and preoperative risk factors were equally distributed across all types of flaps. The overall complication rate was 37% (41/112), most commonly from a slight wound edge dehiscence (n = 16) that healed with local wound care within one month postoperatively. Results of this study show that proper flap selection and the appropriate sequence of flap use significantly improve success rates for ischial pressure sore coverage in both the short- and long-term. Based upon flap reliability (successful healing rates), reusability, and the need to preserve as many future flap options as possible, a rationale for flap selection is presented which can be individualized to any patient.

Modern treatment of complex midfacial defects has evolved over the past 5 years, primarily with the advent of reliable vascularized bone flaps and osseointegrated implants. To determine the effectiveness of these advances, 26 consecutive patients with complex midfacial defects treated from 1991 through 1995 with immediate muscle-flap coverage were evaluated. The etiology of the defect included neoplasm (n = 23) and trauma (n = 3). Seventy-eight percent of the patients received adjuvant radiation therapy. Follow-up ranged from 3 months to 4 years, with a mean of 18 months. Twenty-three patients (88 percent) were reconstructed with a single major procedure. All patients had free-flap reconstruction, and 100 percent of the flaps survived. Late tumor recurrence was seen in 5 of 23 patients (22 percent) and was detected promptly. Aesthetic and functional results were rated good or excellent in 77 and 88 percent of the patients, respectively, as determined by patient questionnaires and physical examinations. Fourteen of 18 patients (78 percent) undergoing partial or complete alveolar ridge resection received dental rehabilitation, 43 percent of whom received osseointegrated implants into either a bone flap or remaining native bone. Osseointegrated implants were inset during the initial reconstruction 50 percent of the time. A treatment algorithm for free-flap selection based on the size of the defect and the bony requirement for reconstruction is presented. Bony restoration is only required in those areas where osseointegrated implants need to be placed. In such cases, the fibula osteocutaneous free flap is the flap of choice. Otherwise, soft-tissue flaps are selected based on wound size. Immediate free-flap coverage provides effective, single-stage treatment, both aesthetically and functionally, for complex midfacial defects.

Despite technical feasibility, composite tissue allotransplantation has not been applied clinically because of immunosuppressive toxicity associated with these highly antigenic allografts. Combination immunosuppression therapy can help overcome this obstacle by allowing lower doses of individual drugs and minimizing toxicity. RS-61443 (mycophenolate mofetil), an effective immunosuppressant that inhibits lymphocyte proliferation, was tested at subtherapeutic doses in combination with cyclosporine (CsA) in a rat hindlimb allotransplantation model with a major antigenic mismatch at the MHC. Five groups were studied: untreated autograft controls (n=4), untreated allograft controls (n=6), allografts receiving low-dose CsA 1.5 mg/kg/day (n=11), allografts receiving low-dose RS-61443 15 mg/kg/day (n=17), and allografts receiving combination low-dose CsA 1.5 mg/kg/day + RS-61443 15 mg/kg/day (n=18). The autograft controls survived indefinitely, while untreated allograft control animals developed severe rejection within 12 days. Subtherapeutic CsA and RS-61443 monotherapy groups developed acute rejection in 64% and 100% of rats, respectively. In contrast, only 11% of rats receiving combination therapy with CsA + RS-61443 at these same subtherapeutic doses developed acute rejection (P < or = 0.0013). Bone marrow toxicity, manifested primarily by anemia and measured objectively by hematocrits, was reduced significantly (P=0.04) in animals receiving low-dose RS-61443 therapy when compared with high-dose controls. These results confirm that subtherapeutic RS-61443 + CsA combination therapy is efficacious in preventing rejection while minimizing toxicity.

Advances in immunosuppression and selective reinnervation may soon make laryngeal transplantation a potential therapy for patients undergoing total laryngectomy. Successful transplantation requires a clear delineation of those vessels necessary to completely revascularize the larynx. Our hypothesis is that the arterial inflow provided by a single superior thyroid artery is sufficient to revascularize the entire larynx. To test this hypothesis, 8 cadavers were studied via either barium latex injection (n = 4) to assess contralateral tissue perfusion or India ink (n = 4), to determine the degree of mucosal perfusion. Following injection via a single superior thyroid artery, all larynges demonstrated either complete, bilateral tissue perfusion evidenced by x-ray visualization of the barium latex injected specimen or bilateral mucosal staining with India ink. We conclude that bilateral perfusion of the entire larynx transplant, including laryngeal and epiglottic mucosa, would occur after revascularization of a single superior thyroid artery. These findings suggest that reliable revascularization of a larynx transplant is technically possible using modern microsurgical techniques.

Complications of irradiated tissue include infections and impaired healing. Although fibrosis and hypovascularity contribute, a cellular mechanism has not been identified. This study examines the effect of radiation (10 to 30 Gy) on neutrophil function in a rabbit wound cylinder model. At 3 to 12 weeks after radiation, subcutaneous wound cylinders were implanted in both irradiated and control fields in 19 rabbits. Wound neutrophils were subsequently assayed for phagocytosis ( 3 H-labeled Staphylococcus aureus assay), superoxide production (cytochrome c reduction assay), and surface Mac-1 expression (flow cytometric assay using MHM 23 monoclonal antibody). Phagocytosis of 3 H-labeled S. aureus was significantly lower in neutrophils from irradiated fields compared with controls at 6 and 12 weeks after radiation (6.5 versus 18.9 bacteria per neutrophil at 12 weeks ; p = 0.027). Stimulated neutrophils from irradiated tissue could not increase superoxide production or Mac-1 expression as much as controls, with differences increasing as postirradiation time increased. The diminished phagocytosis, superoxide production, and Mac-1 expression provide a cellular mechanism that may account for susceptibility to infection and poor healing in irradiated tissues.

Reconstruction of the chest wall requires a thorough knowledge of both the anatomy of the defect and regional tissue with potential for use in defect coverage. The combination of preoperative defect assessment with selection of a reliable reconstructive technique gives the surgeon the ability to provide stable chest wall reconstruction with preservation of form and function.

Patients undergoing laryngopharyngectomy require the restoration of both deglutition and voice. The tubed radial forearm flap offers the combined advantages of rapid harvest, minimal morbidity, long flap pedicle, extraordinary reliability, and the possibility of customizing the flap to fit virtually any defect. Most importantly, this technique provides superior restoration of speech and deglutition.

The history of flap surgery originated several thousands of years ago. As each era of humans learned to apply the principles of anatomy, progress was made in the coverage of difficult and complex wounds. A classification scheme is important not only to organize our thinking, but also to logically plan an operation based on reconstructive requirements. The most important factor in the safe design of flaps is a fundamental understanding of the anatomy based on the arterial supply.

Muscle flap transposition requires a precise knowledge of the vascular and functional anatomy of the muscles used. Safe, effective, one-stage transpositions can be performed in many body regions, as demonstrated in the brief review of our recent experience with this procedure. Our suggestions for further uses of these include distally-based muscle flaps, island muscle flaps, and myocutaneous flaps.

Aeromonas hydrophila infections are a recognized complication of postoperative leech application, and can occur with measurable frequency in populations of patients treated with leeches. We review 11 previously reported leech-related Aeromonas infections and analyze seven unreported cases. These infections range from minor wound complications to extensive tissue loss and sepsis. Often, these infections followed leech application to tissue with questionable arterial perfusion. Onset of clinical infection in these patients ranged from within 24 hours of leech application to 10 days or more after leech application. Late infections may represent bacterial invasion from colonized necrotic tissue. Based on these observations, we recommend that leech applications be restricted to tissue with arterial perfusion to minimize contamination of necrotic tissue. We also recommend that patients treated with leeches receive antibiotics effective against Aeromonas hydrophila before leech application. Patients treated with leeches and discharged with eschars or open wounds might benefit from oral antibiotic therapy until wound closure. These precautions may minimize or eliminate this complication of leech use.

The anterior course of the inferior alveolar neurovascular canal was determined in 52 hemimandibles using high-resolution radiographs. Significant variability was found in its course. It was noted that if the osteotomies for sliding genioplasty were performed at least 6 mm below the inferior border of the mental foramen, injury to the mental nerve would be reduced.

Preliminary reports have indicated that debridement of the bony sequestrum followed by muscle-flap coverage allows successful treatment of chronic osteomyelitis. To determine the long-term effectiveness of this procedure, 34 consecutive patients with chronic osteomyelitis of the distal lower extremity treated with debridement, a 10- to 14-day course of culture-specific antibiotics, and immediate muscle-flap coverage were evaluated. Patients were treated from 1979 through 1984, and long-term (greater than 5 years) follow-up was available for 27 (79 percent). Twenty-three (85 percent) of these patients underwent microvascular muscle transplantation (gracilis or latissimus dorsi), and four underwent local muscle flaps (gastrocnemius or soleus) for immediate wound coverage. Twenty-four patients (89 percent) healed and were without recurrence over long-term (greater than 5 years, mean 7.4 years) follow-up. Of the three with recurrence, two were cured (greater than 5 years follow-up) after additional muscle-flap procedures. Thus the overall success rate was 96 percent, with a minimum 5-year follow-up. Guidelines for muscle-flap selection and treatment techniques in current use are presented. Debridement and immediate muscle-flap coverage provide effective, single-stage treatment of chronic osteomyelitic wounds and allow antibiotics to be restricted to short-term use. Furthermore, muscle flaps covered with skin grafts provide durable coverage while allowing subsequent ancillary procedures (i.e., bone grafts) to be performed under the flaps.

Recent advances in the understanding of the pathophysiology and treatment of osteomyelitis have been discussed. Some of the advances (in either knowledge or technology) that we have found particularly useful include the following: The discovery of additional prognostic factors, which allow more reliable preoperative assessment. The development of the Ilizarov device, which allows bone fixation and later limb lengthening. Confirmation of the effectiveness of single-staged debridement and muscle flap closure. Confirmation that a brief (10 to 14 day) course of antibiotics is as effective as more prolonged therapy. The development of several new free muscle donor sites and a greater appreciation of the need for careful insetting of the muscle. The development of local antibiotic delivery systems, especially continuous antibiotic irrigation catheters. The development of newer oral and intravenous antibiotics that allow outpatient therapy following surgery. The recognition that patients require extended follow-up, and that any recurrences can be successfully treated with a second debridement and muscle flap closure.

Two aspects of the inflammatory response to infection--blood flow alteration and leukocyte mobilization--are investigated in the canine model. The elevation of paired musculocutaneous (MC) and random pattern (RP) flaps allowed comparison of healing flaps with significant differences in blood flow (lower in random pattern flaps) and resistance to infection (greater in musculocutaneous flaps). Blood flow changes as determined by radioactive xenon washout were compared in normal skin and distal flap skin both after elevation and following bacterial inoculation. Simultaneous use of In-111 labeled leukocytes allowed determination of leukocyte mobilization and subsequent localization in response to flap infection. Blood flow significantly improved in the musculocutaneous flap in response to infection. Although total leukocyte mobilization in the random pattern flap was greater, the leukocytes in the musculocutaneous flap were localized around the site of bacterial inoculation within the dermis. Differences in the dynamic blood flow and leukocyte mobilization may, in part, explain the greater reliability of musculocutaneous flaps when transposed in the presence of infection.

Treatment results were compared between mandibular fractures repaired with vitallium miniplates versus intermaxillary fixation (IMF) and wire osteosynthesis in 79 patients treated over a 4-year period. The postoperative courses of 35 patients treated with 46 plates were compared to those of 44 individuals treated with traditional reduction techniques. The plated group contained nine complications (26%) versus ten (23%) in the non-plated group. This difference was not statistically significant, despite the presence of more severe fractures in the plated group. Major complications (nonunions, malocclusions) were noted in only three (8%) of the plated group; there were six complications (14%) in the non-plated group. We conclude that the plating of mandibular fractures incurs no greater overall risk of complications than traditional methods of fixation, and a lower risk of major complications, and that the advantages of plate fixation, including decreased time of intermaxillary fixation and cost effectiveness, make this the method of choice in complex mandibular fractures, even in a high-risk population.

Although free flap transfer is commonly performed to reconstruct defects of the upper two-thirds of the face and scalp, the superficial temporal artery and vein have historically not been considered adequate for microsurgical reconstruction and have rarely been described as recipient vessels. The purpose of this study was to determine the indications for and effectiveness of using the superficial temporal vessels for scalp and face reconstruction.Retrospective chart review on all patients undergoing microsurgical reconstruction for defects of the upper two-thirds of the face between 1996 and 2003 revealed 45 free tissue transfers in which the superficial temporal artery and vein were considered for use as recipient vessels. Flap success rates and postoperative course were evaluated.Forty-three patients underwent 45 free flap transfers. The superficial temporal artery was used as the recipient artery in every case. In three cases, the superficial temporal vein was not suitable as the recipient vein and required use of a vein in the neck. The median length of follow-up was 4 years. Flap survival was 96 percent. Five patients required reoperation for vascular compromise. One of these patients ultimately had flap failure. In that patient, a subsequent attempt at microvascular flap reconstruction was successful using the same superficial temporal artery and vein as recipient vessels.Use of the superficial temporal artery and vein for scalp and face reconstruction is reliable and safe. The superficial temporal artery and vein should be considered as primary recipient vessels in microsurgical reconstruction of the upper two-thirds of the face and/or scalp.

An endoscopic method of mandibular subcondylar fracture repair has been described recently. To determine the effectiveness of this new technique, we longitudinally studied functional, aesthetic, and radiographic parameters following endoscopic repair of 22 subcondylar frac-tures in 20 patients. Restoration of mandibular function was achieved without postoperative maxillomandibular fixation. Premorbid occlusion was restored. Clinical jaw motion was found to progressively increase with a mean interincisal jaw opening of 43 mm achieved after the eighth postoperative week. Patients were pleased with the aesthetic restoration of their chin projection, jaw line, and the symmetric midline movement of the chin point on jaw opening. Anatomic fracture reduction with rigid plate fixation was confirmed on early postsurgical radiographs. Late radiographs showed fracture union without remodeling of the condylar head. Endoscopic subcondylar fracture repair was efficacious at functional, aesthetic, and radiographic restoration of the mandible.

Objective: To establish a treatment algorithm for the long-term surgical management of pressure sores. Design: Retrospective case series. Setting: University-based teaching hospital. Patients: From March 1979 to July 1995, 280 unselected pressure sore reconstructions (113 ischial, 94 sacral, and 73 trochanteric sores) were performed in 201 patients (130 men and 71 women; age range, 16-90 years; mean, 50 years). Of the patients, 90% had severe spinal cord injuries (paraplegia or quadriplegia). Forty-one percent of the wounds were chronic (present longer than 3 months). Main Outcome Measures: Length of stay, postoperative morbidity and mortality, and flap success (defined as a completely healed wound). Results: Overall, 89% of the flaps healed primarily (ischium, 83% [94/113]; sacrum, 91% [86/94]; trochanter, 93% [68/73]). Three fourths of cases were treated in a single stage (debridement and reconstruction). The inferior gluteus maximus island flap (ischium) (94% [32/34]), the V-Y gluteus maximus advancement flap (sacrum) (97% [36/37]), and the tensor fascia lata flap (trochanter) (95% [42/44]) had the highest success rates. Flap success was not significantly affected by the size of the pressure sore or the number of previous flaps used. Postoperative hospital stays averaged 20 days. The overall complication rate was 28%, most commonly from a slight wound edge dehiscence. Conclusions: Flap selection and the appropriate short-and long-term sequence of flap use significantly improve success rates for pressure sore coverage. Reconstruction can be reliably performed in a single stage with a relatively short hospitalization. Arch Surg. 1997;132:868-873

Objective: To establish a treatment algorithm for reconstructing complex midfacial defects. Design: Retrospective case series. Setting: University-based teaching hospital. Patients: Thirty-one consecutive patients were treated from 1991 through 1995. The 18 males and 13 females were aged 15 to 90 years (mean age, 58 years). The cause of the defect included neoplasm (n=27) and trauma (n=4). Reconstruction consisted of 1 of 4 free flaps: rectus abdominis, radial forearm, fibula, or latissimus dorsi. Aesthetic and functional results were determined by patient questionnaires and physical examinations. Main Outcome Measures: Length of stay, postoperative morbidity and mortality, degree of aesthetic and functional restoration, and detection of tumor recurrence. Results: Twenty-seven (87%) of the 31 patients underwent reconstruction with a single major procedure. All of the flaps survived. Postoperative hospital stays averaged 14 days. Late tumor recurrence occurred in 7 (23%) of the 31 patients and was promptly detected. Aesthetic and functional results were rated good or excellent in 77% (24/31) and 87% (27/31) of patients, respectively. Of the 20 patients who underwent alveolar ridge resection, 16 (80%) received dental rehabilitation, 44% of whom received osseointegrated implants into either a bone flap or remaining native bone. Osseointegrated implants were inset during the initial reconstruction 57% (4/7 patients) of the time. Conclusions: For complex midfacial defects, free-flap transfer can be performed with a high degree of success, restoring both appearance and function in most patients. The only instance in which bone is necessary to reconstruct the midface involves those areas in which osseointegrated implants are needed, ie, alveolar ridge (dental implant) and/or orbit (ocular prosthesis). In such cases, the fibula osteocutaneous free flap is the flap of choice. Otherwise, soft-tissue flaps are selected based on wound size. Arch Surg. 1996;131:960-966

While transplantation of the larynx may eventually be useful in post-laryngectomy reconstruction, three criteria must first be met before human transplants can be attempted: transplant viability must be high, immunosuppression must be safe and effective and functional recovery of the larynx must occur. To study these first two criteria, a total of 11 canine larynx transplants were performed: 3 autografts, 6 orthotopic allografts and 2 heterotopic allografts. The rationale and technical performance of these different transplant procedures are reviewed in detail. Orthotopic transplant recipients received cyclosporin A (CsA) while the heterotopic allograft recipients received RS-61443 and methylprednisolone in addition to CsA. Overall, 9 of 11 of the transplants remained viable. In contrast, all 3 autografted animals developed esophageal-cutaneous fistulas; 2 developed sepsis and were sacrificed on post-operative days (POD) 5 and 28, respectively. The third survived for 91 days and demonstrated a high degree of regeneration in the recurrent and superior laryngeal nerves of the transplant. Orthotopically transplanted dogs also had a high morbidity and perioperative mortality (5 of 6 animals). The single “long-term” survivor was treated with CsA alone, but developed complete transplant rejection on POD 33. The two heterotopic transplant recipients had no perioperative morbidity and the combination of CsA, RS-61443 and methylprednisolone given these latter animals was effective in the longterm prevention of rejection. One of these heterotopic recipients died of sepsis on POD 68 while the other remained alive and well on POD 168. Our present findings show that currently available microsurgical techniques allow experimental canine laryngeal transplantation to be done with significantly high transplant viability rates. In the dog, CsA alone is inadequate for the long-term prevention of transplant rejection while combined therapy with CsA, RS-61443 and methylprednisolone can provide long-term rejection-free larynx transplant survival. The newly developed heterotopic larynx transplant model allows studies of transplant viability, rejection mechanisms and neural regeneration and functional recovery to be performed with minimal animal morbidity and lowered research costs.

Gossypol is present in antiinflammatory poultices made from the medicinal tree Thespesia populnea. Isolated human neutrophils exposed to 3-20 microM gossypol for 15-90 min were assayed in vitro for superoxide production and surface expression of Mac-1 (CD11b/CD18). Gossypol increased superoxide production in a time- and concentration-dependent fashion consistent with a moderate, delayed respiratory burst. Surface Mac-1 expression was increased within 15 min by 3-5 microM gossypol, resulting in a 14-fold increase over controls and a threefold greater increase over that produced by PMA. Staurosporine failed to block gossypol induction of superoxide and Mac-1, while EDTA inhibited induction of Mac-1 only, implicating a calcium-dependent mechanism. Gossypol increased intracellular calcium to peak levels, but in a delayed fashion as compared to FMLP. These findings demonstrate that gossypol is a highly potent stimulant of Mac-1 expression and suggest at least two protein kinase C-independent pathways of neutrophil activation. The resultant exhaustion of neutrophils may account for the antiinflammatory properties of plants containing gossypol.

The requirement for effective, minimally toxic immunosuppression remains a major obstacle to performing human composite tissue allotransplantation. The skin component of composite tissue (e.g., limb) allografts is especially antigenic, necessitating toxic immunosuppressant doses to prevent or reverse acute rejection. In previous experiments, RS-61443, an experimental mycophenolic acid ester that inhibits lymphocyte proliferation with minimal toxicity, prevented acute limb allograft rejection in rats for more than 8 months when started on the day of transplantation. In this study, the ability of RS-61443 to reverse established acute rejection was tested in a rat model of hindlimb allotransplantation. Brown-Norway donors and Fischer 344 recipients provided a MHC mismatch for orthotopic midfemur limb transplants that were performed with microsurgical repair of femoral vessels and sciatic nerve. Three groups were studied: untreated allografts (n = 6); allografts receiving RS-61443 at 30 mg/kg/day, started on postoperative day 7 (n = 11); and allografts receiving RS-61443 at 30 mg/kg/day, started on postoperative day 9 (n = 9). Skin and soft tissues were biopsied periodically to assess rejection. Untreated allografts had complete acute rejection within 12-13 days. Animals in both the 7- and 9-day groups developed moderate to severe rejection clinically and histologically before initiation of immunosuppressive therapy. In both groups, RS-61443 was able to reverse rejection completely in all animals from which biopsies were obtained at the time of death at 9-16 weeks after transplantation (P < 0.007). RS-61443 was highly effective as a primary immunosuppressant for reversing established acute rejection in rat hindlimb allografts.

Although technically possible, limb allotransplantation has not been applied clinically. The skin component is especially antigenic, requiring high immunosuppressant doses with an unacceptable toxicity profile. RS-61443, an experimental mycophenolic acid ester that inhibits lymphocyte proliferation without major systemic toxicity, was tested as an immunosuppressant to prevent rejection of rat hindlimb allotransplants. Utilizing Brown-Norway donors and F344 recipients to provide a major mismatch at the MHC, midfemur orthotopic limb transfer was performed with microsurgical repair of femoral vessels and sciatic nerve. Four primary groups were studied: autografts (n = 4); untreated allografts (n = 6); allografts receiving CsA 10 mg/kg for 20 days, then twice per week (n = 6); and allografts receiving RS-61443 30 mg/kg/day (n = 6). Skin and soft tissues were biopsied to assess rejection. Autografts had indefinite limb survival, while untreated allografts had complete acute rejection within 10-12 days. Five of the six CsA rats developed delayed mild-moderate acute rejection within 6 months. In contrast, 5 of the 6 RS-61443 rats had no rejection after at least 32 weeks, while the sixth rat developed only slight rejection on skin biopsy. All animals regained full sensation and partial functional return. RS-61443 is highly effective as a primary immunosuppressant for hindlimb allotransplantation. The disturbing moderate rejection observed in CsA animals, which was absent with RS-61443, may significantly hamper function of transplanted limbs.

There is a need in plastic and reconstructive surgery for a method of monitoring flaps and replants pre- and postoperatively. This study evaluates color flow Doppler done as a monitoring technique for microvascular vessels. The capability of color flow ultrasound to monitor venous and arterial insufficiency and occlusion was studied by means of an experimental system in the Yucatan miniature swine model. A circulatory circuit in line with a magnetic flow probe is created. Measurements are made on the isolated hind limb of the animal. Color flow ultrasound is demonstrated to be a technique that is sensitive to venous and arterial insufficiency at flow rates as low as 3.0 ml/min. Characteristic waveform patterns are shown to predict arterial and venous insufficiency before they actually progress to occlusion. A clinical series of 25 postoperative patients is presented, consisting of volunteer studies as well as pre- and postoperative examinations of free flaps and replantations. Color flow ultrasound is shown to visualize a spectrum of pre- and postoperative microvascular conduits encountered in plastic and reconstructive surgery.

Little is known about the differences in behavior of leukocytes of specific types of wounds. It has been observed clinically that certain tissue types are considerably more able to resist bacterial inoculation, and some experimental evidence points to differences in leukocyte function. How is leukocyte activation affected by its immediate wound milieu, and what is it about a wound that causes a leukocyte to activate?

Over a 5-year period at the University of California San Francisco, 42 patients who required microvascular reconstruction for abnormalities in the head and neck area were identified. Twenty-four patients (Group I) underwent reconstruction for a variety of neoplastic and non-neoplastic conditions and did not receive radiotherapy. Eighteen patients (Group II) had undergone previous radiotherapy averaging 6,090 rads. The mean ages for Group I and II patients were 40.7 and 55.5 years, respectively. In Group I, 13 muscle, 7 fasciocutaneous, 4 osteocutaneous, and 2 jejunal transfers were performed. In Group II, 11 muscle, 5 fasciocutaneous, 3 osteocutaneous, and 2 jejunal transfers were performed. Flap survival at 3 months was 88% in Group I and 95% in Group II. Wound complication rates were similar in both groups (15% Group I, 19% Group II), as was donor site morbidity (15% Group I, 29% Group II). Operative times (10.9 hours Group I, 10.6 hours Group II) and median postoprative hospitalization (14 days Group I, 16 days Group II) were comparable as well. Four of the five patients in whom the flap procedures failed were subsequently treated by a second microvascular reconstruction. Previous irradiation of the recipient bed did not appear to affect the success of subsequent microvascular reconstruction or the difficulty of such reconstruction as judged by operative time.

Progressive tissue expansion induces significant gross, histologic, and bony changes in skulls and long bones of neonatal miniature swine. These bony changes consist of erosion underlying tissue expanders, with bony lipping and bone deposition at the periphery of the expander. Cranial suture lines underneath expanders appear effaced and convoluted. Serial CT scans reveal decreased bone thickness and volume (p less than 0.02) but identical bone density (p = 0.60) beneath expanders. Increased bone volume and thickness occur at the periphery of expanders (p less than 0.02). Bone density (CT number) is unaffected by tissue expansion in both cranial and long bones. These findings have histomorphometric correlates: Osteoclastic bone resorption occurs underneath expanders with periosteal reaction at the periphery of expanders. Cranial sutures are similarly affected, but no cranial synostosis results. No changes to the inner table of the skull or stigmata of increased intracranial pressure were observed either in CT scans or in behavioral changes in long-term animals. The pathophysiology of bony changes is a remodeling effect, not one of simple pressure deformation. Increased bone resorption and complete inhibition of bone formation occur until the pressure is removed. Cranial bone is significantly more affected than long bone. After removal of the expanders, reparative bone remodeling begins within 5 days and nearly complete healing of the cranial defects occurs within 2 months (p less than 0.02). No plagiocephaly results despite early coronal suture changes. On the basis of this study, we conclude that tissue expansion causes significant but reversible effects, readily monitored by high-resolution CT scans, on neonatal and infant cranial and long bones.

• Perineal wounds developing after abdominoperineal resection result in chronic purulent drainage and intermittent episodes of sepsis and are generally unresponsive to conservative medical and surgical treatment. Thirteen consecutive patients (aged 27 to 74 years; mean, 48 years) who underwent debridement and immediate muscle flap closure of these wounds were analyzed to identify risk factors for delayed healing and to evaluate the effectiveness of muscle flap coverage. Three risk factors were identified: preoperative or postoperative radiation therapy, resection for recurrent carcinoma, and inflammatory bowel disease. A total of 19 muscle flaps (11 gracilis, five gluteal thigh, two gluteus maximus, and one rectus abdominis) were used to close these wounds. During an average 3.5-year follow-up, four (31%) minor complications and one (8%) recurrence were noted to occur. Muscle flaps provide safe, effective, single-stage procedures for the closure of chronic perineal wounds. ( Arch Surg. 1990;125:1371-1377)

The in vivo physiologic response to gram-negative bacterial inoculation within wound cylinder spaces enclosed by the deep surface of paired musculocutaneous and random-pattern flaps was studied in the canine model. Leukocyte function was assessed by calculating the following values: leukocyte counts, bacterial counts, phagocytic indices, and intracellular bacterial killing ratios. The following results were observed in the wound cylinder spaces after bacterial inoculation with 5 X 10(7) of Pseudomonas aeruginosa bacteria: (1) the numbers of mobilized leukocytes within each wound cylinder space flap were not statistically different, (2) the bacterial counts were significantly lower in the musculocutaneous flap wound cylinder space at both 24 and 48 hours, (3) the phagocytic activity of the leukocytes within musculocutaneous flap wound cylinder space was 1.5 times greater than the leukocytes in the random-pattern flap wound cylinder space, and (4) the intracellular bacterial killing ratio of the musculocutaneous flap leukocyte was 83 percent versus 26 percent in the random-pattern flap leukocyte, a significant difference.

Breast implantation is performed primarily for three indications: breast augmentation, reconstruction after mastectomy for cancer, and reconstruction after prophylactic mastectomy. Outcome is judged by the safety of the surgery and the quality of results in terms of breast shape, size, and consistency and patient satisfaction. Since the introduction of the silicone-gel–filled elastomer-envelope prosthesis in the 1960s,1 implant design and surgical technique have been extensively modified in response to local complications and concern about implant safety.2 Implant failure — either rupture or leakage of implant contents — has received considerable attention because of concern that the release of silicone gel into . . .