Faculty Bibliography

Respiratory distress in premature newborns is associated with deficiency of surfactant in the bronchoalveolar lining fluid; this may be influenced by a local deficiency of antioxidants. Severe L-buthionine-S,R-sulfoximine-induced depletion of glutathione (GSH, a major antioxidant) in rodents is associated with lung type 2 cell lamellar body damage and decreased concentrations in lung and bronchoalveolar lavage fluid (BALF) of phosphatidyl choline (a major component of surfactant). At birth, prematurely born newborns (30-34 weeks) had lower peripheral venous plasma GSH concentrations than term (> 36 weeks) babies; these levels decreased further with increasing prematurity (< 27 weeks, with respiratory distress). On day 2, the peripheral venous plasma GSH concentrations reached a nadir, and the lowest levels were found in the most premature newborns. Lymphocyte GSH concentrations were lowest on day 2 and day 7, and in prematures (< 27 weeks, with respiratory distress) remained below adult lymphocyte GSH levels for at least 4 weeks. At birth, prematures (< 27 weeks, with respiratory distress) had a central plasma arterio-venous (A-V) GSH gradient across the lung (an estimate of lung uptake of GSH) of 0.72 +/- 0.15 (mean +/- SD) mumol/L; on day 2, the A-V gradient did not change significantly (0.49 +/- 0.09 mumol/L). At birth, these prematures had markedly decreased BALF GSH concentrations (compared with adult levels), and they were not significantly changed during the first 4 weeks of life. These results suggest that GSH deficiency is present in prematures and that it increases with the degree of prematurity. At birth, GSH deficiency will compromise the lungs' defense against oxidative stress injury. Oxidative stress is likely to increase if hyperoxic treatment is given for respiratory distress in these infants

Posttransplantation lymphoproliferative disorder (PTLD) is a well-described complication of the systemic immunosuppression required for successful organ transplantation. Lesions of PTLD often occur in the region of the head and neck and require otolaryngologic evaluations. Although the majority of reported cases of PTLD are associated with cyclosporine immunosuppression, recently, PTLD has been described in patients treated solely with the newer systemic immunosuppressive agent tacrolimus (FK 506). As an introduction to tacrolimus and to PTLD as one of its complications, a case of PTLD presenting as airway obstruction in a child treated solely with tacrolimus immunosuppression is described. In addition, a review of tacrolimus and PTLD in patients under tacrolimus immunosuppression is presented to familiarize the otolaryngologist with this important new immunosuppressive agent and a potential complication of its use

This article reminds the otolaryngologist of a rare but real complication of mastoid surgery. Additionally, we have offered a straightforward method to repair the resulting defect

A cochlear lubricant may facilitate the surgeon's ability to place the electrode array deep within the cochlea. Patient performance with the multichannel cochlear implant may be enhanced with a deeper electrode insertion. Theoretically, deeper insertion and stimulation will recruit and activate more surviving spiral ganglion neurons. Several studies have shown that neuron survival is a factor for cochlear implant success, especially in the postmeningitis patient. We studied the histologic and electrophysiologic effects of the intracochlear injection of three potential lubricants in the guinea pig: glycerin, hyaluronic acid, and hydroxypropyl methylcellulose. All three have approved medical uses, reduce friction, and are readily available. Results show that when compared to surgical controls (cochleostomy without injection), there is no significant reduction in the spiral ganglion neuronal count at 2 and 8 weeks postinjection, and the dendrite and axon histology is well preserved. Injection of any of the substances within the cochlea causes severe hearing loss (detected by direct round window electrocochleographic responses to auditory stimuli) that only partially recovers with time. These findings suggest that any of the three tested substances could be considered as lubricants for intracochlear electrode insertion