Giant pleomorphic adenoma of the parotid gland: case report and review of the literature.

Pleomorphic adenomas account for the majority of parotid masses, typically arising in the tail of the gland and enlarging slowly over time. The vast majority are 2 to 6 cm in size when resected. We report resection of the largest benign mixed tumor recorded in the modern English language literature. An 85-year-old reclusive woman had a 20-year history of an enlarging right periauricular mass that had begun bleeding several days prior to admission. The patient ultimately underwent resection of the mass, which measured 26 cm in diameter, weighed 6.85 kg, and proved on pathologic examination to be a benign mixed tumor without malignant degeneration. The implications of this unusual case for the management of mixed tumors are discussed, and a review of the world literature on giant pleomorphic adenomas is presented.

Computer-based physician education.

Physicians are turning to computers with increasing frequency to access patients' records and laboratory values, to communicate with colleagues, and to keep current with the developments in their field. This article reviews the impact of the computers on the education of medical students and on continuing education for residents and practicing physicians. Furthermore, it emphasizes the importance and need for educating physicians about computers and the basic principles behind their development.

Internet image database: development and implementation.

The widespread acceptance of World Wide Web (WWW) hypermedia protocols allows rapid cross-platform development of database interfaces. Using the WWW as the interface promotes easy integration of databases with other publicly available Internet resources. We present our experience with an image database search program (IDBS) developed on the PC platform using freely available UNIX development tools. The database routines were written in PERL. The image database program provides a familiar user interface to a collection of clinical images stored in digital form, either on local media or on the Internet. The design goals of the project and the strategies used to meet them are presented. The source code and a demonstration database are available on the Internet at http:/(/)www.webmedix.com/idbs.

Insulin-dependent diabetic microangiopathy in the inner ear.

Thickening of the basement membrane in capillaries is implicated in the microangiopathic complications of diabetes mellitus. This study was designed to evaluate microangiopathic changes of the inner ear associated with insulin-dependent diabetes mellitus (IDDM) and concurrent moderate-intensity noise exposure. Male Sprague-Dawley rats were injected with streptozotocin (65 mg/kg) to induce IDDM. Half of the control and diabetic animals were exposed to chronic noise of 95 dB over the 6-month study period. Photomicrographs of the capillaries in the stria vascularis were obtained by transmission electron microscopy, and basement-membrane thickness was measured with an image processing system. This study quantitatively demonstrates basement-membrane thickening consistent with diabetic microangiopathy in the inner ear of IDDM rats. Noise exposure did not significantly change basement-membrane thickness in either diabetic or control animals.

Nasal cavity area in term infants determined by acoustic rhinometry.

The present study was undertaken to determine whether a modification to commercially available acoustic rhinometry (AR) instrumentation might allow equipment designed for use in adults to determine accurately the nasal cavity configuration of infants and children. The standard wave tube was replaced with a version having a narrow (0.312-cm2) internal diameter (ID). Before use with neonates, the accuracy of this instrument was evaluated using the nasal cavity of a full-term infant cadaver. Acoustic nasal area curves were compared to area measurements of polyvinylsiloxane nasal casts and direct volume measurements of the specimen. AR correlated well with nasal cast data (r = .88) for total nasal cavity area. The acoustic method underestimated the total area at the nasal valve by only 1.8 mm2 (22.1 mm2 vs. 23.9 mm2) and overestimated choanal area by 10 mm2 (56.9 mm2 vs. 46.9 mm2). In addition, AR measured total nasal volume to within 5.2% of the value obtained by direct measurement. In a cohort of 10 normal, term infants, the mean acoustic value for total nasal valve area was 19.2 +/- 0.05 mm2 and for total nasal volume was 1.76 +/- 0.53 cm3. This, the first report of nasal area and volume information in live infants, suggests that the modified AR device has utility both in airway research and as a nasal patency screening tool in the pediatric population.

Artifacts associated with acoustic rhinometric assessment of infants and young children: a model study.

The present study was undertaken to determine in model studies whether currently available acoustic rhinometry instrumentation might be used to analyze the nasal cavity configuration of infants and children. A simple nasal cavity model was constructed using eight Lucite inserts that were placed between standard nosepieces provided by the manufacturer and a 35-cm-long polyvinyl chloride pipe closed at its distal end. To simulate the nasal valve, the inserts were 12 mm in length and had apertures ranging in diameter from 2 to 9 mm. A series of experiments was conducted to evaluate the accuracy with which the acoustic rhinometer measured the size of each insert aperture and the configuration of the model system distal to that aperture. Transmission losses caused errors in the area measurement of the insert aperture and the tube distal to the insert. When the insert aperture was < 6 mm in diameter (0.28 cm2), the aperture area was overestimated by > 10%, whereas the area of the distal tube was underestimated by > 10%. As a result of response lags, the acoustic rhinometer also failed to provide an accurate indication of insert length. Finally, oscillation artifacts caused estimates of the distal pipe area to fluctuate. These three systematic errors are described, and their potential impact on acoustic rhinometry in children is discussed.