Faculty Bibliography

Malformations of the arterial and venous systems often are manifested in the head and neck. Low-flow venous malformations are generally benign lesions; however, complications, such as bleeding, obstruction, pain, or cosmetic deformities, may warrant surgical intervention. Treatment of these lesions can be challenging. Laser photocoagulation, particularly with the neodymium-yttrium aluminum garnet (Nd-YAG) laser, has been successful in the majority of patients, with minimal morbidity and good results. Thirty-two patients with low-flow venous malformations of the head and neck were treated with the Nd-YAG laser using low-power density and intermittent short exposures in a punctate nonoverlapping technique. When possible, two glass slides were used to compress the lesion. There was excellent regression with minimal damage to the surrounding tissue. No major complications or morbidity, postoperative pain, or mortality occurred. Lesions occurring in some areas of the head and neck would not have been amenable to standard surgical excision. Follow-up period has ranged from 1 to 8 years. Nd-YAG laser photocoagulation has proved safe and effective for treatment of low-flow vascular malformations of the head and neck

Dizziness is often a patient's shorthand description of a variety of symptoms, many of which have nothing to do with balance. Vertigo consists of an abnormal sensation of motion, whereas dysequilibrium is a disturbance of balance without necessarily a sensation of motion. A careful history usually determines the nature of the patient's presenting symptoms, and a thorough workup will often give rise to a diagnosis. Vertigo of vestibular origin may be treated with a variety of medications or, when these fail, surgery. Surgery should preserve hearing when at all possible. Balance rehabilitation is a useful modality for the patient who does not compensate spontaneously or who does not respond to the medical or surgical treatment of imbalance

This study examined the morphological development of single inhibitory arborizations in the gerbil central auditory brain stem. Using a brain slice preparation, neurons of the medial nucleus of the trapezoid body (MNTB) were filled with horseradish peroxidase (HRP), and their complete arborizations were analyzed along the tonotopic axis of the lateral superior olive (LSO). The projections in neonatal animals displayed well-defined arbors that were ordered appropriately within the LSO. It was evident from the axonal pathways that the MNTB afferents could correct for projection errors after reaching the postsynaptic population. As development progressed, a number of arbors established diffuse or inappropriate projections within the LSO. These immature arborizations were no longer apparent by 18-25 days postnatal. The anatomical specificity of arbors at 12-13 and 18-25 days was quantified by measuring the distance that terminal boutons spread across the frequency axis. There was a significant reduction of this distance in older animals. In addition, there was a significant reduction in the mean number of boutons per arbor between 12-13 days and 18-25 days. The maximum nucleus cross-sectional area continued to increase through 15-16 days, indicating that the refined arbors occupied an even smaller fraction of the postsynaptic structure. Taken together, these observations suggest that central inhibitory arbors form exuberant contacts that must be eliminated during development

We have defined conditions permitting the in vitro growth of human laryngeal papilloma cells at the air-liquid interface. Using this model system, retinoic acid has been found to modulate the differentiation of human laryngeal papilloma cells along two different pathways. At low concentrations of retinoic acid [10(-9) mol/L and 10(-8) mol/L], the cells formed a stratified squamous epithelium with a differentiation-specific protein staining pattern identical to that found in vivo. At higher concentrations of retinoic acid [10(-7) mol/L and 10(-6) mol/L], the cells differentiated into a columnar epithelium with occasional ciliated cells, lacking the markers of squamous differentiation. Analysis of the human papillomavirus DNA content revealed that as the concentration of retinoic acid increased, the viral DNA content decreased. This system is proposed as a model to further investigate the differentiation defects of human laryngeal papilloma cells and the regulatory role of retinoic acid in the clinical expression of human laryngeal papillomatosis

Classifying soft tissue tumors of the head and neck is often difficult for both surgeon and pathologist because of the potential similarities in appearance of metastatic lesions, epithelial tumors, lymphomas, and inflammatory processes. This paper discusses four unusual soft tissue tumors of the head and neck: osteosarcoma of the mandible, biphasic synovial cell sarcoma of the hypopharynx, soft part sarcoma of the maxillary sinus/alveolus, and adult rhabdomyoma of the larynx. Precise diagnosis of these lesions requires adequate tissue sampling, immunocytochemical staining, and electron microscopy. The clinical and pathological features of these tumors, as well as a practical approach to the diagnosis, is presented

This study is a randomized clinical trial to compare the efficacy and safety of one single-channel implant (the 3M/Vienna intracochlear device) and two multichannel cochlear implants (the Nucleus 22-channel device and the Smith & Nephew Richards Ineraid device). Seven Veterans Administration centers are participating in the study. The patient population consists of 82 veterans with postlingual, bilateral profound sensorineural hearing losses who obtain no benefit from amplification. All potential subjects were screened with a battery of audiologic tests. The three device groups are balanced on baseline patient characteristics. One month after operation, the devices were stimulated and programmed and the patients evaluated. Follow-up evaluations were completed at 3 and 12 months poststimulation and then annually until the end of the study. The 12-month data indicate that performance with the multichannel devices is superior to that with the single-channel device

Since Crile's original description of neck dissection in 1906 (Crile GW: JAMA 47:1780-1786, 1906), a variety of neck incisions has been described, suggesting that none is sufficiently versatile to satisfy the criteria necessary for the ideal neck flap. Single transverse neck incisions (STNI) for complete neck dissections have been performed since the 1950s but are not as commonly used as trifurcate incisions. A criticism of the STNI is that the perceived difficulty exposing the surgical field may compromise removal of disease and impair normal surgical technique, resulting in a higher incidence of recurrent neck disease and postoperative complications. One hundred nine patients with squamous cell carcinoma of the head and neck were operated using the STNI. There was no incidence of skin necrosis or carotid artery hemorrhage. Fourteen percent developed fistulae and 12% developed wound dehiscences. Recurrence in the operated neck was not identified. Cosmesis was considered good in all patients. We conclude that STNI does not result in an increased incidence of postoperative complications or recurrent neck disease compared with standard trifurcate incisions

Composite data describing ocular pharmacokinetics are unreliable because of intersubject variation. To address this problem, an animal model was developed in which multiple aqueous samples from single subjects were obtained. Following direct anterior chamber or intravenous administration of amikacin or chloramphenicol, pharmacokinetic analysis of drug concentrations in the serum and anterior chamber was performed by using a nonlinear least-squares regression program. The number of anterior chamber paracenteses performed did not alter the beta elimination rates or percent penetration into the anterior chamber. The aqueous humor and peripheral-compartment terminal slopes were identical. These data indicate that complete ocular concentration-time curves can be obtained without altering antibiotic pharmacokinetics. Following direct injection into the anterior chamber, the elimination rates for both antibiotics followed a one-compartment model, whereas those following intravenous administration best fit an open, first-order, two-compartment model. Following intravenous administration, the anterior chamber elimination rate constants for both drugs were equal to that of the serum and significantly longer than that following direct injection. The elimination rates of both drugs following direct injection were similar. Systemic administration resulted in drug levels in aqueous humor that persisted longer than those following direct injection. Chloramphenicol, a lipophilic compound, gave higher mean concentrations in aqueous humor than did amikacin. Our model provides a new approach which rigorously examines ocular pharmacokinetics and provides data which suggest that for selected compounds the parenteral route of administration is preferable.

Although diffuse cervical lymphadenopathy is one of the earliest and most common findings in patients with AIDS, the appropriate diagnostic approach in these patients has yet to be determined. Fine-needle aspiration (FNA) was performed on 26 patients with AIDS in order to evaluate the role of FNA in patients with diffuse cervical adenopathy. Specimens were sent for cytology, bacterial culture, fungal culture, and acid-fast smear and culture. Ten patients had positive findings, including toxoplasmosis, histoplasmosis, tuberculosis, atypical mycobacterium, and methicillin-resistant staphylococcal infection. All patients with either unilateral adenopathy or lymph nodes 3 cm or larger had positive aspirates. A statistically significant difference between patients with lymph nodes smaller than 2 cm and those with nodes larger than 2 cm was found. Fine-needle aspiration of a representative node in patients with AIDS may allow prompt diagnosis of diffuse lymphadenopathy. Rapid initiation of appropriate treatment can lead to symptomatic improvement. The need for excisional biopsy of involved lymph nodes may be obviated. Fine-needle aspiration is recommended as a diagnostic tool in selected patients with diffuse cervical lymphadenopathy and AIDS.