Faculty Bibliography

Lengthening of the canine mandible using an intraoral distraction device was performed in order to study the effects of distraction on the associated muscles of mastication. Biopsies of the masseter and digastric muscles were taken after lengthening at four different time intervals to assess the temporal changes in the masticatory muscles of 10 dogs. Biopsies of the muscles on the contralateral side also were taken from 6 of these dogs before lengthening to establish a control group. Each biopsy was analyzed histologically and spectophotomerically for RNA, DNA and protein content. The digastric muscle underwent transient atrophy with initiation of distraction but regenerated completely after 48 days of fixation. The masseter muscle was unchanged initially but showed evidence of atrophy only after 20 mm of distraction it continued to exhibit evidence of atrophy during fixation. Protein synthesis was decreased significantly during periods of atrophy in the masseter; no such change was noted in the digastric. Unlike the masseter, the digastric fibers lie in a plane parallel to the vector of distraction. These findings suggest that any muscle affected by skeletal distraction in the same plane or vector (e.g., digastric) adapts with compensatory regeneration and hypertrophy. Moreover, those muscles lying in a different plane (e.g., masseter) show persistent evidence of atrophy with decreased protein synthesis

Two sisters presented to our medical center with nontraumatic cerebrospinal fluid (CSF) fistulas from left sphenoid sinocranial junction defects. One sister had recurrent meningitis over a 20-year period that prompted a skull base evaluation. Four years later, her younger sister presented with profuse CSF rhinorrhea. Transethmoid sphenoidotomy with sinus obliteration and lumbar-subarachnoid temporary CSF diversion successfully treated one sister, while the other required reoperation and permanent lumbar-peritoneal shunting. In both cases the skull base defect was identically located in the posterolateral left sphenoid sinus. Embryological considerations, evaluation and management are presented

End-to-side neurorrhaphy is a technique that may provide a solution for the problem of distal target reinnervation without injury to the original donor nerve. The technique drew extensive attention after Viterbo reported his experiments in 1992; however, to date, the animal models used to elucidate the process of lateral axon sprouting had the disadvantage of substantial injury to the donor nerve, raising questions about the origin of axons reinnervating the nerve graft. In this report, a new model in the rat is introduced, in which the donor nerve is not damaged and an additional target can be innervated via a nerve graft. The saphenous nerve represents the axonal conduit; the proximal end is coapted end-to-side to the sciatic nerve at the site of a perineurial window. The distal end is passed through the adductor muscles and coapted distally in an end-to-end fashion with the obturator nerve. In one group, a partial neurectomy was performed at the site of coaptation, which led to a lower Sciatic Functional Index (SFI). In the second group, the creation of a perineurial window yielded a normal SFI after end-to-side neurorrhaphy. Compared to the partial neurectomy group, the perineurial window end-to-side neurorrhaphy resulted in significantly less axons in the graft. The new model has the following advantages: (a) minimal injury to the donor nerve; (b) provision of a single additional target (gracilis) whose functional recovery can be assessed morphologically and behaviorally; (c) an opportunity to understand lateral sprouting by providing a non-injury model in which axonal invasion of the graft can originate from nodal axonal outgrowth; and (d) establishment of a noninjury model that can have widespread clinical applications

Free-muscle transplantation is the treatment of choice for long-standing facial paralysis. It enables the reconstructive surgeon to restore facial movement and some emotional animation. Despite all technical innovations and 20 years of experience with free-muscle transplantation, the aesthetic and functional outcomes of the surgery are still unpredictable. The present report reviews 100 free-muscle transplantations to the face by a single surgeon and analyzes various preoperative, intraoperative, and postoperative factors in relation to the functional recovery of the muscle transplants. These factors were demographic variables such as age, gender, and etiology as well as intraoperative variables such as choice of muscles, number of nerve coaptations, and ischemia time of the muscle. Additionally, four independent raters not involved in the care of these patients rated standardized preoperative and postoperative videos and judged the functional and aesthetic outcomes. From 1981 to 1993, 93 patients with facial paralysis underwent free-muscle transplantation. A total of 100 muscles were transplanted, since 7 patients received two muscle transplants. There were 33 male and 60 female patients ranging in age from 3 to 57 years, with an average of 22.2 +/- 14.9 years. The gracilis muscle was used in 63 cases of free-muscle transplantation, while the pectoralis minor was used in 34 cases. In 2 patients a segment of the rectus abdominis was transferred, and in 1 patient a small segment of the latissimus dorsi was transferred. In 89 patients the onset of muscle function was reported. The range was from 6 to 48 weeks postoperatively. The average was 21.6 +/- 9.14 weeks after muscle transplantation. The correlations showed a trend to earlier onset of function and higher aesthetic rating in young female patients. The intraoperative ischemia of the free muscle did not correlate with the onset of muscle function. Using a five-step scale of judgments, a higher postoperative rating was seen in 94 percent of the patients, and 80 percent of all patients achieved a moderate or better result

Sixteen patients (mean age, 1.9 years) underwent split-thickness calvarial bone grafting using a full-thickness craniotomy, high-speed drill, and osteotomes for bone harvesting. The minimal calvarial bone thickness for a successful graft was found to be 7 mm. All patients were diagnostically studied preoperatively with computed tomographic scans and skull films. The mean follow-up was 2.9 years (range, 0.75-7.9 years). All patients had successful graft take. There were no infections or mortalities. Continued graft growth was seen in all patients. There was one dural tear during harvesting with no cerebrospinal fluid leak or postoperative sequelae. This analysis indicates that split-thickness calvarial grafts can be safely and adequately performed in children as young as 13 months of age

The purpose of this study was to evaluate the application of bioabsorbable fixation devices in reconstructive craniofacial procedures in the pediatric population. We reviewed 22 cases in which bioabsorbable plates and screws were used in craniofacial surgery for reconstruction. The procedures were performed in a 7-month period. The patients ranged in age from 5 to 228 months at the time of surgery (mean, 76.7 months). The postoperative clinical follow-up ranged from 2 to 16 weeks. The fixation devices were evaluated with regards to satisfactory fixation at the time of procedure. The postoperative follow-up evaluated clinical wound healing, signs of infection or local inflammation, and visibility or palpability of plates through the skin. All patients except one showed satisfactory wound healing with no sign of infection or local inflammation. The plates provided satisfactory fixation and were not visible through the skin. Two patients had plates that were palpable at the 4-month follow-up period. One patient with repair of a blow-out fracture of the orbit with resorbable mesh had redness and swelling over the wound site 2 weeks postoperatively with resolution 4 weeks postoperatively. Our early experience suggests reabsorbable fixation is an attractive option in pediatric plastic and craniofacial surgery. With further experience, this technology may represent the standard of care in reconstruction of the infant calvarium