Faculty Bibliography

A model to study the blink reflex in the experimental setting has been established. The behavioral, electrophysiologic, pathologic, and surgical methods and results obtained parallel those utilized and observed in the human and simulate the problem of facial paralysis. The observation that the blink can be elicited in an animal model, with the same stimuli as in humans, strengthens the value of this model, as do the similarities seen in the electrophysiologic recordings of NCV studies. The dual innervation of the rat eye sphincter allows application of the principle of selectively neurectomizing eye branches and 'borrowing' motor-nerve fibers from the normal side, without causing eye-sphincter paralysis, a concept employed extensively in cross-facial nerve-grafting procedures in humans with facial paralysis

The accumulation of leukocytes is believed to contribute to reperfusion injury following ischemia. The purpose of this study was to determine if pentoxifylline (PTX) would ameliorate reperfusion injury by preventing activation of leukocytes. Male Wistar rats received 40 mg/kg of PTX orally in water for 6 days, and a single dose of PTX (30 mg/kg) intraarterially before experiments. Control measurements of red-cell velocity and inside diameter were made in first-through-third-order arterioles (1A-3A) of the cremaster muscle, along with the number of rolling and sticking leukocytes (WBC) in venules and the density of flowing capillaries, by intravital microscopy. The muscles were then subjected to total ischemia for 2 hr by arterial clamping, followed by a repeat of the measurements during reperfusion. The number of both rolling and sticking WBCs was not different between the two groups during the control period but, following reperfusion, there were significantly fewer WBCs rolling and sticking in the venules of the PTX group at the measured times (immediately, 1, 2, and 3 hr after reperfusion). Arteriolar blood flow was lower than initial values during the first hour of reperfusion in both groups. But while blood flow decreased further in the untreated group, it significantly improved in the PTX group. There were no significant differences in arteriolar diameter or density of flowing capillaries between the two groups at any time. Treatment with PTX prevented accumulation of rolling and sticking leukocytes following reperfusion. This may contribute to the improved arteriolar blood flow following 2 hr of ischemia

Eighty-six patients with anterior neck burn sequelae underwent scar resection up to the limits of the aesthetic unit of the neck and immediate resurfacing with a scapular-parascapular free flap (the extended scapular flap). The flap was raised in all patients above the deep fascia as a thin skin-subcutaneous tissue flap, providing an initially acceptable aesthetic result. The flap was anastomosed to the facial artery and vein. The donor area was closed directly, or a 4- to 5-cm-wide skin graft was used which could be completely removed in a secondary procedure if the patient requested it. There were four failures early in the series but no losses in the last 70 patients. In order to improve the final aesthetic result, 45 patients underwent complementary defatting procedures (average of three) and Z-plasties initiated 30 days after the initial surgery at intervals of 1 month. Analysis revealed 96 percent good aesthetic results (as determined by the cervicomental angle obtained and the subjective opinion of the patients). There were no recurrences of scar contractures, and good function of the neck was regained in the majority of the patients. Anterior neck burn sequelae thus can be safely treated with en block resection and resurfacing using this flap

The structure of the submental platysma muscle was evaluated in 20 preserved cadavers. Four distinct patterns were identified, depending on the pattern of merging of the right and left platysma bundles. Fifteen percent of cases showed a complete platysma diaphragm submentally, while in the other 85% there was some degree of midline dehiscence. In the 85% of cases where right and left fibers merged or crossed to form a V or U shape, the apex of the V or U was measured relative to the chin point. The distance between right and left fibers was measured at two locations posterior to the chin point. The width of the midline dehiscence (when present) was 6-24 mm (mean 11.8 mm) 1 cm posterior to its apex and 10-44 mm (mean 20.00 mm) 2 cm posterior to the apex. The wider and more divergent the dehiscence and the more U-shaped the dehiscence between left and right platysma bundles, the greater may be the tendency to a 'turkey gobbler' deformity with inadequate medial support for the skin and subcutaneous tissues

Available literature on penetrating trauma in the USA was reviewed to determine the prevalence, etiological factors, and societal cost of penetrating trauma. Penetrating injuries accounted for 39,888 deaths in 1989 and was the eighth leading cause of death. Etiological factors include increasing ownership of firearms, alcohol consumption, recreational drug use and trafficking, occupational risks, and socioeconomic factors. These injuries account for the fourth leading cause of estimated years of potential life lost. Corrective strategies and research are severely limited by the disproportionately low research funding.