Androgen-induced changes in laryngeal growth patterns were studied using a sheep animal model. Forty-eight lambs were divided into eight treatment groups. Lambs in seven of the groups were castrated at birth, while lambs in the eighth group served as an intact (noncastrated) control. Six groups were then treated with varying doses of testosterone and dihydrotestosterone, while the seventh served as a castrated, nontreated control. All animals were killed and gross dissections of the larynges were performed. Thirty-four linear and angular measurements were obtained from each larynx. The mean superior thyroid horn separation showed the most dramatic androgen-induced effect (p = 0.023). Laryngeal anterior-posterior diameter, superior thyroid horn height, posterior thyroid cartilage width, thyroid cartilage angle, and vocal process to arytenoid base distances all demonstrated positive dose-response relationships. Hypoandrogenic levels appeared to have an inhibitory effect upon laryngeal growth when compared to castrated controls.
The relationships among the paratubal muscles were studied in human fetal and adult Eustachian tubes. That which has, in recent years, been labeled the tensor veli palatini muscle actually consists of two distinct groups of muscle fibers: a medial group, henceforth termed dilatator tubae, and a lateral group, called tensor veli palatini. The latter was found to have no Eustachian tube origin, but was continuous superiorly with the tensor tympani muscle. The dilatator tubae muscle was found to have a tubal attachment. The participation of this muscle system in the normal functioning of the Eustachian tube-middle ear system in man, and the problems inherent in the development of animal models simulating the physiology of the physiology of the human system, are discussed.
The primate nasopharynx-eustachian tube-middle ear complex is being used to model both the normal and pathologic functions of the human eustachian tube by several researchers. An extensive search of the literature has indicated little detailed information on the primate eustachian tube/middle ear system. This study was undertaken to define the anatomical characteristic of the system in the Rhesus monkey (Macaca mulatta) and to determine the limits on the use of the monkey as a model of human eustachian tube function. Although the direct application of morphologic data to explain the function of a system is tenuous, the data on the Rhesus monkey eustachian tube appears to be consistent with that published for other mammals. The tensor veli palatni muscle appears to be the only muscle to act directly on the tube and effect tubal dilation. The muscle is attached to the lateral membranous tubal wall along its extrabullar extension. The muscle has an inferior attachment to the posterior hard palate and thus possesses a vector directed inferolaterally; contraction would appear to pull the membranous wall inferiorly and laterally, resulting in the tubal dilation. The eustachian tube relationships of the salpingopharyngeus, levator veli palatini, and internal pterygoid muscles are described. Their possible role in primate tubal function is minimal at best.
Lesions in the substance of the cheek--the buccal space--may present diagnostic and management difficulties. The buccal space, that potential fascia space lying within the bulk of the cheek, is anatomically described. While the history and physical characteristics of the buccal mass and selected radiographic and special procedures may suggest a specific cause, the diagnosis is often elusive and requires removal of the mass for histologic evaluation. The surgical approach to a mass in the cheek is governed by its location within the buccal space and by the index of suspicion of malignancy. The preauricular, submandibular approach is the authors' choice for most buccal space lesions. Five case reports are presented to illustrate features in the diagnosis and management of a buccal space mass.
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