Faculty Bibliography

The potential widespread use of tissue-engineered matrices in soft-tissue reconstruction has been limited by the difficulty in fabricating and confirming a functional microcirculation. Acellular dermal matrix placed in a soft-tissue pocket acts as a scaffold to be incorporated by the host's fibrovascular tissue. A new method for noninvasive real-time observation of functional microvascular networks using orthogonal polarization spectral (OPS) imaging has recently been reported. Arterioles, venules, and capillaries can be directly visualized, and the movement of individual blood cells through them can be observed. The present study was performed to investigate the use of prefabricated acellular dermal matrix with an arteriovenous unit for the repair of abdominal muscle defects. OPS imaging was used to determine the presence of a functional microcirculation in the neovascularized matrix. In Sprague-Dawley rats, vascularized matrix was prefabricated by placing the superficial epigastric artery and vein on a 2-cm x 2-cm implant-type acellular dermal matrix in the thigh. Three weeks after implantation, the matrix-arteriovenous unit was elevated as an axial-type flap and a 2-cm x 2-cm full-thickness block of abdominal muscle immediately superior to the inguinal ligament was resected. Additional procedures were performed according to group: no repair (group 1, = 20); repair with nonvascularized acellular dermal matrix (group 2, = 20); repair with devascularized acellular dermal matrix (group 3, = 20); and repair with vascularized acellular dermal matrix (group 4, = 20). OPS imaging (field of view, 1 mm in diameter; scan depth range, 0.2 mm) was performed on both sides of each flap on a total of 10 random distal regions before and after pedicle transection in group 3 and with the pedicle preserved in group 4. Hernia rate and duration of survival were compared for 21 days. OPS imaging showed directional blood cell movement through the capillary network in all areas scanned in group 4. No microvascular perfusion was observed after pedicle transection in group 3. Hernia rates of 100, 80, 90, and 0 percent were seen in groups 1, 2, 3, and 4, respectively. Median survival times of 9, 11.5, 9, and 21 postoperative days were noted in groups 1, 2, 3, and 4, respectively. Histopathologic analysis with factor VIII revealed full-thickness infiltration of the matrix by endothelial cells, signifying newly formed blood vessels. Repair of abdominal muscle defects using vascularized acellular dermal matrix resulted in no hernia and survival of all animals for the duration of study. However, repairs using avascular or devascularized matrix resulted in significant rates of hernia and decreased survival. Acellular dermal matrix can be prefabricated into vascularized tissue using an arteriovenous unit and used successfully to repair abdominal muscle defects. OPS imaging allowed for high-contrast direct visualization of microcirculation in previously acellular tissue following prefabrication with an arteriovenous unit

The management of primary and recurrent giant incisional hernias remains a complex and frustrating challenge even with multiple alloplastic and autogenous closure options. The purpose of this study was to develop a reconstructive technique of restoring abdominal wall integrity to a subcategory of patients, who have failed initial hernia therapy, by performing superior and lateral myofascial release. Over a 1.5-year period, 10 patients with previously unsuccessful treatment of abdominal wall hernias, using either primary repair or placement of synthetic material, were studied. The patients had either recurrence of the hernia or complications such as infections requiring removal of synthetic material. The hernias were not able to be treated with standard primary closure techniques or synthetic material. The average defect size was 19 x 9 cm. Each patient underwent wide lysis of bowel adhesions releasing the posterior abdominal wall fascia to the posterior axillary line, subcutaneous release of the anterior abdominal wall fascia to a similar level, and complete removal of any synthetic material (if present). The abdominal domain was reestablished by releasing the laterally retracted abdominal wall. The amount of available abdominal wall tissue was increased by wide release of the cephalic abdominal wall fascia overlying the costal margin and the external oblique fascia and muscle laterally. If needed, partial thickness of the internal oblique muscle and its anterior fascia were also released laterally to perform a tension-free primary closure of the defect. All repairs were closed with satisfactory functional and aesthetic results. All alloplastic material was removed. Fascial release was limited so as to close only the hernia defect without tension. No significant release of the rectus sheath and muscle was needed. Good, dynamic muscle function was noted postoperatively. All repairs have remained intact, and no further abdominal wall hernias have been noted on follow-up

Bannayan-Zonana syndrome (BZS) is a genetic disorder with autosomal dominant inheritance characterized by macrocephaly and multiple hamartomas of mesodermal origin. Here we present a patient with BZS manifested by many of the classic features, as well as a high-flow upper extremity arteriovenous malformation (AVM). Although this rare syndrome was initially described in 1971, to our knowledge, this is the first report showing an association of AVM with BZS and the first report of this syndrome in the radiologic literature

Treatment of neuroma-in-continuity involves neurolysis or resection with interposition nerve grafting of the involved segment. These techniques may be complicated by loss of remaining conduction through axons that were intact prior to surgical neurolysis or grafting. The authors have shown previously that axonal regeneration occurs in an autologous bypass graft in the rat model. They applied this technique to a neuroma-in-continuity of the peroneal nerve of a 22-year-old woman who sustained an injury to the peroneal nerve after arthroscopic surgery, with excellent results. Nerve bypass may be the procedure of choice for treatment of neuroma-in-continuity

Avoidance of complications in tissue expansion requires careful outpatient observation and consistent follow-up-two factors that are difficult to manage in a city hospital-based population. To determine the complication rate of tissue expanders in a given population, the authors reviewed retrospectively 34 tissue expanders placed in 30 patients at a New York City public hospital over a 7-year period from 1989 to 1996. The mean age of the patients at the time of insertion was 25 years (range, 11 months-65 years). The most common conditions for treatment were nevi (N = 11), burn scars (N = 8), breast reconstructions (N = 8), and spina bifida (N = 4). Complications occurred in 22 of 34 expanders (65%). Complications included deep infection (N = 11), exposure (N = 7), breakdown of the surgical wound (N = 4), cellulitis (N = 3), drainage (N = 1), and deflation (N = 1). Major complications resulted in premature removal in 13 of 34 expanders (38%). Minor complications leading to successful completion of the expansion process occurred with 9 of 34 expanders (27%). No complications were recorded in the remaining 12 of 34 expanders (35%). Although tissue expansion is a potentially safe and effective method of reconstruction, this review should alert the surgeon to the distinct challenges that may be encountered in the public hospital

We present the management challenge provided by a patient with kaposiform hemangioendothelioma associated with Kasabach-Merritt phenomenon. A female child presented at 14 months of age with an ecchymotic swelling of her right upper arm and axilla. Subsequently, she developed profound thrombocytopenia and hypofibrinogenemia (Kasabach-Merritt phenomenon). Biopsy of the lesion revealed kaposiform hemangioendothelioma, which has been reported as the predominant pathologic diagnosis associated with Kasabach-Merritt phenomenon. To achieve involution of the lesion and preserve function of the arm, the following interventions were involved: embolization, systemic interferon, cyclophosphamide, epsilon aminocaproic acid, and compression therapy. The clinical management of this patient was formidable until we arrived at the proper combination of therapies. Multimodal intervention may be required to manage fastidious hemangioendotheliomas of childhood, achieve clinical improvement, and prevent further morbidity

Thrombocytosis in patients undergoing free tissue transfer for coverage of posttraumatic lower extremity defects may be associated with an increased incidence of microvascular thrombosis. Patients with isolated lower extremity trauma have an elevated platelet count that peaks approximately 2 weeks after injury. It is our theory that a humoral component of trauma sera is responsible for the induction of this thrombocytosis. Eight patients with isolated soft-tissue and bony trauma were included in the study. Serum was collected at baseline and throughout the study period. Platelet count, leukocyte count, hemoglobin concentration, and hematocrit were determined. Immunoassay for human interleukin-3 (IL-3), IL-6, and IL-11 as well as granulocyte macrophage colony stimulating factor (GM-CSF) were performed by solid-phase enzyme-linked immunosorbent assay. Balb-C mice were then injected intraperitoneally with the human trauma sera from all time points. Blood was collected at baseline and throughout the study period for determination of platelet count, hemoglobin, and hematocrit. Mean initial platelet count in the 8 human subjects was 152,000 per cubic millimeter with an average peak to 642,000 per cubic millimeter. IL-3, IL-11, and GM-CSF were not detectable in the serum of any patient. Elevated levels of IL-6 were detected in all patients in a nonspecific pattern. In the murine model, an early and late thrombocytosis was elicited. The early peak averaged 78.6% over baseline whereas the late peak average 81.0% over baseline. The induction by human trauma sera of an early and late thrombocytosis in this mouse bioassay supports the theory of humoral mediators. The humoral mediators are yet to be determined but may include IL-6

Segmental loss of a peripheral nerve has been a challenging reconstructive problem. Management of the nerve gap has been accomplished classically with nerve grafting. However, autogenous nerve grafts are not always available for bridging large nerve gaps, and clinical results of large nerve cable grafts have been disappointing. Newer techniques concentrate on nerve lengthening with different methods. Tissue expansion of peripheral nerves has been producing promising results. Since the introduction of the Ilizarov external fixator, much attention has turned to limb-lengthening techniques and studies investigating the results of nerve and soft tissues lengthened during the course of this procedure. Primary nerve distraction may be an alternative to nerve elongation, by expansion or nerve grafting to repair the peripheral nerve gap. This study describes a device and a model for peripheral nerve distraction in a rat. Primary nerve distraction will need to be subjected to vigorous studies before clinical application

Balloon dissectors are inexpensive, disposable devices originally designed to provide rapid, atraumatic development of the work space needed for endoscopic hernia repair. We sought to evaluate the utility of these devices for endoscopic brow lift. Cadaver testing (n = 5) was followed by clinical use with assessment of flap loss, dissection time, completeness of dissection, and, more subjectively, amount of bleeding and tissue trauma. Dissection time over the forehead was less than 3 minutes in all cases; the remainder of the procedure was completed in times ranging from 20 to 35 minutes. No partial or total flap loss was experienced (n = 12). Bleeding after dissection was minimal. Dissection was possible in either the subperiosteal (n = 7) or subgaleal plane (n = 5), creating a smooth optical cavity. Dissection advanced to nearly the orbital rims, leaving only nerve identification, muscle removal, and flap elevation/fixation to complete the brow lift. Balloon dissection devices allow rapid mobilization of tissue planes with a minimum of effort. The feasibility of using balloon devices to speed and simplify endoscopic brow lift dissection has been demonstrated. Their full utility must await the results of outcome studies in a larger clinical series and must be balanced against their cost