Faculty Bibliography

A considerable body of literature advocates and defines treatment of vocal cord cancer with posterior extension by hemilaryngectomy. The present study was carried out to determine the feasibility of using a newly devised pedicle flap, composed of thyroid cartilage and inferior constrictor muscle, to replace the ablated arytenoid cartilage. Animal investigation revealed satisfactory viability of the pedicle flap in canines, and in humans, five patients with T2 glottic carcinoma demonstrated excellent postoperative deglutition and return of voice. The results of the study indicate that this surgical technique merits consideration for its use in minimizing protracted glottic incompetence following hemilaryngectomy. The thyroid cartilage-inferior constrictor muscle pedicle flap may also prove useful as partial cricoid replacement in selected cases of subglottic extension and in cricoid reconstruction following trauma

Use of commercially available urea differentiation disks is a rapid and convenient means of determining the urease activity of mycobacteria. In the study performed, paper disks containing Ewing's Urea R Broth were compared with two other methods of testing for urease production. Over 1,500 tests were performed with recent patient isolates from which at least 15 different species of mycobacteria were identified. The tests were read at intervals for 72 h, and a comparison of test results as to rapidity and accuracy for each species was tabulated. The urea disks showed a faster reaction time when compared with the other two methods. They also showed a high percentage (79 to 100%) of reliability for each species on the first run, based on the expected response.

The most challenging laryngotracheal stenosis are those that exceed 5 cm in length and involve more than one area of the larynx and trachea contiguously. A successful technique for the repair of these injuries with a three-stage laryngotracheal trough was created followed by anterior tracheal wall replacement with a skin-Marlex-muscle pedicle flap.

Indirect laryngoscopy is one of the procedural methods used for achieving a histopathologic diagnosis of cancer of the larynx. A chronologic historical summary of the development of mirror laryngoscopy is presented. The details of the procedure employed for obtaining a biopsy with the aid of topical anesthesia is discussed.

Summary--The laryngeal phonatory reflex through the internal branch of the superior laryngeal nerve (SLN) was investigated by means of anesthetization of the nerve, after which acoustic signals were subjected to computer analysis to determine how anesthesia affected basic vocal parameters. Results showed that the anesthetization did not affect the abrupt cycle-to-cycle frequency changes and also did not influence the gross control of the fundamental frequency. But slower fluctuation of the fundamental frequency increased following anesthesia. From these results, it is suggested that the anesthetization of the internal branch of the SLN may derange the fine control mechanism of the larynx without affecting overall or gross performance of the phonatory apparatus.

Otocysts explanted from 12th-gestation-day mice and maintained in organ culture under went a series of developmental changes which paralleled those that occurred in vivo and which resulted in the formation of a sensory epithelium of the vestibular type. At the time of explantation presumptive vestibular sensory epithelium consisted of cells that were undifferentiated, pseudostratified and rapidly proliferating. The only microtubules present were those of the mitotic apparatus. After 4 days of in vitro development cells comprising the presumptive vestibular sensory epithelium were less pseudostratified and more elongate; their nuclei had assumed a basal orientation and there was a clear maginal velum. Longitudinally oriented cytoplasmic microtubules were present at the apices of some cells; they were often grouped around a centriole which may have served as a nucleation centre for their assembly. After 7 days of in vitro development mitosis had ceased and supporting cells had innervated hair cells were present: both types of cells were always longer than they were broad and were often highly asymmetrical. Hair cells were flask- or columnar-shaped, with a nucleus situated in the basal third of the cell. Most mitochondria in hair cells were located in the apical third of the cell. The same distribution of mitochondria and nuclei was evident in supporting cells. Microtubules occurred throughout the length of the supporting cell and were always parallel to its longitudinal axis. In hair cells microtubules were more frequent than in supporting cells: the majority were parallel to the longitudinal axis of the cell but there were two exceptions. First, at the apex of hair cells some microtubules were oriented transversely and diagnonally: these were probably involved in the development and maintenance of the constricted apex of these cells. Secondly, microtubules appeared to be randomly arranged in the narrow region of the cytoplasm between the ventral surface of the nucleus and the base of the hair cells. Microfilaments were confined to the basal third of hair cells where their orientation paralleled that of microtubules. The possible functions of microtubules and microfilaments in the development of hair cells and supporting cells of the mouse vestibular epithelium are discussed.