Faculty Bibliography

Synechiae formation is a frequent occurrence after endoscopic sinus surgery and may cause symptomatic sinus outflow tract obstruction. Various means are used to reduce the incidence of synechiae formation. These include meticulous operative technique, partial middle turbinate resection, middle meatus spacers or stents, and postoperative debridement. The microdebrider is a powered rotary shaving device that precisely resects tissue, minimizing inadvertent mucosal trauma and stripping. We present 40 cases of endoscopic sinus surgery performed with the microdebrider. Patients had at least a 5-month follow-up and demonstrated rapid mucosal healing, minimal crust formation, and a low incidence of synechiae formation. These initial data suggest that the microdebrider may be advantageous in surgery for chronic sinusitis

Distraction osteogenesis is the current method of choice for bone lengthening. Despite the gain in experience, various complications are reported, among them, adverse effects on peripheral-nerve function. In order to thoroughly investigate the effect of distraction on neural tissue, a distraction osteogenesis model in the rat was established, using the femur of 30 Sprague-Dawley rats. The animals were randomized in three groups, following different rates of distraction (0.5 mm, 1.0 mm, and 1.5 mm/day) for 50, 25, and 16 days, respectively, so that the final length of distraction was the same in all groups. The mean sciatic function index ranged near normal in all groups. All groups demonstrated decrease of conduction velocity and the area under the curve of the compound action potential, while morphologic alterations consisted of decrease in the number of axons and evidence of active degeneration. Animals in Groups 1 (0.5 mm/day) and 2 (1 mm/day) displayed comparable changes, while in Group 3 animals (1.5 mm/day), changes were significantly more adversely dramatic. The safest and fastest rate of distraction in this rat model was determined to be 1 mm/day

The classic hypoglossal transfer to the facial nerve is invariably followed by complications caused by tongue atrophy. In 1984, Terzis introduced the 'baby-sitter' procedure which involved a formal cross-facial procedure, in addition to partial neurectomy of the hypoglossal nerve, and an end-to-side coaptation with the ipsilateral facial nerve. This reported study provides, for the first time, quantification of the number of hypoglossal motor fibers needed to successfully restore eye sphincter function, using an end-to-side coaptation with preservation of the tongue. Thirty adult Sprague-Dawley rats were divided into six groups: control, denervated, perineurial window, 20 percent partial neurectomy (PN), 40 percent PN, and 80 percent PN. The procedure involves interposing a nerve graft (saphenous) between the partially severed XII nerve and the upper zygomatic branch of the facial nerve. Evaluation of the behavioral data (blink reflex) revealed good-to-superb return of the blinking mechanism in the 40 percent group, without significant tongue atrophy. Electrophysiologic data in the 40 percent neurectomy group demonstrated superiority to the other groups. Quantitative axonal morphometry of the coaptation sites and graft, as well as motor end-plates of the orbicularis oculi muscle and tongue showed the 40 percent partial neurectomy group to be the optimal group

Hippocrates provided the first written description of the peripheral nervous system (PNS), as early as the 4th century B.C., and later Herophilus identified nerves as such, distinguished them from tendons; he also traced nerves to the spinal cord. The traditional Hippocratic teaching of the time, however, doubted that nerve healing occurred. Through the subsequent centuries, several papers were written about the PNS but, without sufficient understanding of anatomy, physiology, and the regenerative capacity of the PNS, it is not difficult to comprehend the frustration that might have been encountered by surgeons in dealing with nerve injuries and their subsequent repair. This was probably the reason why nerve repair was rarely actually undertaken prior to the 19th century. A plethora of studies on the PNS and its regeneration has been reported over the last 150 years and has provided us with current knowledge. It is important, before describing the most recent developments in the area of peripheral nerve regeneration, to briefly outline the major advances over the last century. Currently, the therapeutic approaches taken toward the patient with peripheral nerve injury change continuously. Sophisticated advances in technology, cellular and molecular neurobiology, and electron microscopy will doubtless optimize reconstructive strategies in treating nerve injury. A greater awareness and understanding of the nerve ultrastructure, as well as the underlying mechanisms of the regenerative process and those factors detrimental to nerve regeneration, will assist in the successful repair of nerve injury. This paper reviews the cellular, biochemical, and ultrastructural elements of nerve injury and repair, and the rationale for current reconstructive strategies and techniques

PURPOSE: This study is a retrospective chart review designed to evaluate the incidence and reasons for removal of plates and screws after Le Fort I osteotomy. PATIENTS AND METHODS: The study sample consisted of patients who underwent Le Fort I osteotomy at the University of California, San Francisco, and Northwestern University in Chicago between December 1985 and December 1994. All patients in the study were treated with internal fixation using 2.0-mm plates and screws. All data were obtained from medical records and operative reports. The following intraoperative variables were evaluated: hardware material, plate size and shape, plate location, screw size, graft material, and intraoperative complications. For patients requiring removal of hardware, the number, location and type of plates and screws removed were recorded, as well as the reasons for removal. RESULTS: A total of 738 plates were placed in 190 patients. Twenty-one of the 190 patients (11.1%) had at least a portion of the hardware removed because they either requested removal or required removal secondary to complications related to the plate or screw. This represented 70 of 738 plates (9.5%). The percentage of titanium plates removed was greater than the percentage of Vitallium plates removed. The reasons for removal included pain, palpation by the patient, sinusitis, temperature sensitivity, infection, and patient request. CONCLUSION: Only a small number of patients (10.6%) develop complications from plates or screws that required their removal. In each case, prompt removal constituted adequate management