Faculty Bibliography

Serial measurements of blood pressure, body weight, food and water intake, and salt and water excretion were compared in two groups of spontaneously hypertensive rats (SHR) over a 12-day period: control SHR (n = 11) and a group (n = 9) which received supplementary 5-hydroxytryptophan (5-HTP; 2 mg/ml) in its drinking water. During the final 4 days of study, both groups received additional oral carbidopa (50 mg/kg twice a day) to inhibit peripheral, but not brain aromatic L-amino-acid decarboxylase (LAAD), an enzyme necessary to the formation of 5-hydroxytryptamine (5-HT, serotonin) from 5-HTP. 5-Hydroxytryptophan increased urinary 5-HT and its metabolite 5-hydroxyindoleacetic acid (5-HIAA) markedly; following carbidopa, urinary 5-HT, and to a lesser degree urinary 5-HIAA, decreased, whereas brain 5-HT and 5-HIAA increased. Spontaneously hypertensive rats treated with 5-HTP plus carbidopa had significantly lower blood pressure levels, lower pulse rates, reductions in food and water intake, salt and water excretion, and a loss of body weight, when compared with the control SHR. These data indicate that enhanced brain formation of 5-HT can give rise to metabolic and circulatory responses with a resultant lowering of blood pressure

Adult epiglottitis in patients with acquired immunodeficiency syndrome has not been previously reported. A pale, floppy epiglottis with supraglottic edema, cervical lymphadenopathy, a normal to low white blood count without a shift to the left, and rapidly progressive airway obstruction characterize this entity. In this small series of patients, conservative medical management was not successful, and aggressive airway intervention with appropriate intravenous antibiotic therapy was necessary

Indications for repair of nasal septum perforations include excessive crusting, recurrent bleeding, whistling, and pain. Large subtotal perforations usually are less symptomatic, but smaller defects (less than 1 cm) may need repair. Tragal cartilage with perichondrium autograft was used to repair these perforations. After the septal defect was debrided, this free graft was harvested and used to fill the defect. This technique was attempted in ten patients with septal perforations, none secondary to systemic illnesses. Nine of these patients had successful closure of their perforations

The hypotheses that selective formation of nerve-muscle connections depends upon intrinsic cellular properties, endowed either by the cell's rostral-caudal position in the embryo or its lineage, were tested directly in Xenopus embryonic cell cultures. The position or the lineage of embryonic cells was traced in vitro by previous injection of fluorophore-conjugated dextran molecules into individual blastomeres. Synaptic efficacy was assayed by recording synaptic currents from neurite-contacted muscle cells in the culture, and the physical affinity of neurites for muscle cells of different positional or clonal origins was assayed by counting the frequency of association between the neurites' growth cones and the muscle cells. Both assays showed no apparent preference between nerve and muscle cells of similar rostral-caudal positions or clonal origins, suggesting that there is little position- or lineage-dependent selectivity in the initial nerve-muscle interactions

During the past 10 years discrete middle ear congenital cholesteatomas have been detected with greater frequency in young children. The increased recognition of this condition is probably related to the pediatricians' greater awareness of this defect, their improved facility with pneumatic otoscopy, and effective audiometric and tympanometric screening procedures. This early detection while the lesions are small and localized facilitates their surgical removal. Clinically, it would appear that congenital cholesteatomas can be subdivided into two categories according to their anatomic locations. The anterior lesions present as an isolated pearl that arise from an area on the anterior surface of the malleus, are usually associated with normal hearing, and have pneumatized mastoids. The posterior lesions do not seem to originate from a clearly defined anatomic area, have a higher incidence of sclerotic mastoids, and erode the ossicular chain commonly producing a hearing loss. The anterior middle ear cholesteatoma probably arises from a persistent epidermoid formation, a structure that normally is present during fetal development of involutes by the 33rd week of gestation. The origin of cholesteatomas arising in the posterior middle ear space remains more controversial

MR and CT are complementary studies in evaluating inflammatory disease or neoplasms of the mastoid and middle ear cavities. CT should be performed prior to MR in the evaluation of patients with primary temporal bone pathology because of its ability to detect and delineate both soft tissue and bony abnormalities. CT should be performed whenever intratympanic or facial nerve pathology is suspected, even if the MR examination is normal. MR can be used to further characterize tympanic cavity masses as effusion, glomus tumor, hemorrhage or cholesterol granuloma. The prospect of Gd-DTPA-enhanced MR promises increased sophistication in the detection of glomus tumors and facial nerve neuromas. Noncontrast MR cannot differentiate between cholesteatoma and granulation tissue. The efficacy of Gd-DTPA in inflammatory disease of the temporal bone awaits further investigation

Airway complications following elective cricothyroidotomy were reviewed in 48 adult cardiothoracic surgery patients. A 52% incidence of airway complications was found and manifested by failed or delayed decannulation, extensive subglottic granulation tissue, stenosis, vocal cord paralysis, and aspiration pneumonia. The most common cause for decannulation difficulty was subglottic stenosis (50%). Several risk factors were specifically identified, including a period of cricothyroid cannulation exceeding 30 days, the presence of diabetes, and advanced age. These findings suggest that airway sequelae following cricothyroidotomy in cardiothoracic surgery patients is higher than previously reported. Indications and risk factors for cricothyroidotomy are discussed