Expression of hypoxia inducible factor 1 alpha and Von Hippel Lindau protein in human middle ear cholesteatoma.

OBJECTIVE: To evaluate the role of hypoxia in cholesteatoma progression. STUDY DESIGN: Immunohistochemical analysis of paraffin-embedded human specimens. METHODS: Thirteen middle ear cholesteatomas and 10 samples of normal human external ear canal skin were stained immunohistochemically for the presence of hypoxia inducible factor 1 alpha (HIF 1 alpha) and Von Hippel Lindau protein. Specimens were then analyzed semiquantitatively. RESULTS: Staining for both antibodies could be detected in all cholesteatomas (perimatrix and matrix), as well as in the samples of normal human ear canal skin. Cholesteatoma specimens showed statistically significant increased staining when compared with normal human skin and mucosa. The age of patients and relapse surgery affected immunohistochemical staining of HIF 1 alpha and Von Hippel Lindau protein. CONCLUSIONS: Elevated staining intensities for HIF 1 alpha and Von Hippel Lindau protein in cholesteatoma tissue indicated that cholesteatoma may be hypoxic. In addition, our data indicated that relapse cholesteatomas yield a higher degree of hypoxia than ears without surgery.

Labyrinth anesthesia--a forgotten but practical treatment option in Ménière's disease.

The aim of this study was to determine the efficiency of labyrinth anesthesia - the intratympanic instillation of lidocaine--in the treatment of Ménière's disease and to recall a forgotten method. Twenty-four patients (15 male, 9 female), aged from 19.7 to 80.6 years (mean: 47.8 years) with the clinical diagnosis of unilateral Ménière's disease who underwent labyrinth anesthesia in our department were included in this retrospective study. After local anesthesia of the tympanic membrane, a solution of 4% lidocaine and furfuryladenine (Kinetin) was instilled into the tympanic cavity. Patient records, a questionnaire and a physical examination were used to evaluate vertigo control, hearing loss, tinnitus, and quality of life according to the AAO-HNS criteria before and after surgery. Postoperatively, 87.5% of patients reported at least a noticeable decrease of vestibular symptoms, 66.7% of these patients were free of attacks for an average of 26.5 months. Postoperative hearing was the same or even improved in 87.5% of our patients. Tinnitus was not affected in any individual. Based on the findings presented herein, we consider labyrinth anesthesia a practicable and, due to its safety, highly recommendable therapeutic option for patients suffering from Ménière's disease.

Is there a double innervation of the tensor tympani muscle in humans?

The middle ear muscles and their function have not yet been fully explored. The statement of Lawrence, for example, that the tensor tympani muscle of humans might have a dual innervation has never been proven or disproven. The question is of great interest; in our opinion, it represents one of the key questions in the putative afferent feedback loop of the middle ear muscles in humans. A light microscopic study was performed on 16 tensor tympani muscles taken from 11 cadavers. Six muscles were taken out in toto and stained according to the modified method of Sihler. The remaining 10 muscles were dehydrated and embedded in paraffin. In 5 of these muscles, complete transverse serial sections were made on a microtome at 7 microm and alternately stained by silver impregnation, S-100 protein immunohistochemistry, and ferric oxide. In the remaining 5 muscles, complete longitudinal serial sections were made at 10 microm. These sections were alternately stained by the methods of Cason and Maskar. Neither the surgical microscopic investigation nor the light microscopic investigation revealed any innervation to the human tensor tympani muscle other than the one arising from the mandibular branch of the trigeminal nerve. Our findings, apart from the fact that they clearly refute an unproven hypothesis, might represent another small step toward understanding the innervation of the tensor tympani muscle.

Intraoperative electromyography for identification of the trapezius muscle innervation: clinical proof of a new anatomical concept.

OBJECTIVE/HYPOTHESIS: There is still considerable controversy among surgeons on trapezius muscle innervation. In addition, the rate of unexpected postoperative trapezius pareses is unacceptably high. Recent anatomical findings might answer most of the questions. The objective of the present study was to clinically prove the recent anatomical findings, especially the concept of the innervation of the descending part of the trapezius muscle. STUDY DESIGN: Intraoperative electromyography of the spinal accessory nerve and its branches in the posterior triangle of the neck. SETTING: Intraoperative electromyography was performed during 17 modified radical neck dissections on 14 patients of both sexes ranging in age from 44 to 68 years (mean age, 56 y). Potentials were registered through pairs of needle electrodes placed in each of the three parts of the trapezius muscle. Intraoperatively, the spinal accessory nerve and its fine cranial branch passing toward the descending part of the muscle were identified and stimulated in the posterior triangle of the neck.RESULTS Stimulation of the fine cranial branch of the spinal accessory nerve led to a clearly visible and recordable contraction in the descending part of the trapezius muscle in all patients. Stimulation of the main trunk of the spinal accessory nerve in the posterior triangle of the neck distal to the above-mentioned branching led to a clearly visible and recordable contraction in the transverse and ascending parts of the muscle. CONCLUSIONS: The results strongly support recent anatomical findings showing that, functionally, the most important descending part of the trapezius muscle is innervated by a fine single branch arising from the spinal accessory nerve in the posterior triangle of the neck. This may help to prevent more patients undergoing modified radical neck dissections from shoulder-arm syndrome.