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The sinus tympani (ST) is a critical anatomic region of the temporal bone. It lies medial to the facial nerve, between the ponticulus and the subiculum, and therefore is not easily visualized by routine surgical approaches to the middle ear and mastoid. This limited access makes the ST a site that is notorious for residual cholesteatoma. An extensive evaluation of the anatomic dimensions of the ST was made from human temporal bones. Three hundred twenty-seven bones were examined at four standardized levels to describe the dimensions and anatomic relationships of the ST with other structures of the temporal bone. The region of the stapedial tendon was found to be the most limited anatomic substructure in the vicinity of the ST. This study demonstrates the feasibility of a retrofacial approach to the ST as an aid in eradication of otherwise hidden disease.

Lateral surgical approaches to the base of the skull through the temporal bone often result in a large cavity with exposed dura and vascular structures and no possibility of reconstruction of the middle ear conductive hearing mechanism. Subtotal petrosectomy with tympanomastoid obliteration provides a relatively safe and secure closure of the surgical defect in the temporal bone and eliminates the problems associated with an open mastoid cavity. Eradication of all accessible air cell tracts and mucosa in the petrous pyramid, obliteration of the eustachian tubal orifice, closure of the external auditory canal, and fat obliteration of the middle ear and mastoid clefts are essential in the procedure. Over the last 10 years this technique has been utilized in 372 base of skull procedures with a complication rate of less than 5%. Infection occurred only in those cases with draining cavities or contaminated wounds.

The diminishing number of cases of otosclerosis limits the training experience in stapes surgery during residency. Results are suboptimal. Closure of the preoperative air conduction to within 10 dB of bone conduction was obtained in only 64 % of resident cases Efforts to maximize experience and improve results include closer faculty supervision, use of one stapedectomy technique, and a prospective study of individual residents' performance.

Bell's palsy in children occurs infrequently and carries a good prognosis for ultimate recovery. However, results of electrical testing have been reported only sparsely. This paper details the authors' experience with five patients under age 18 who met the criteria for facial nerve decompression in adults. All underwent decompression via the middle fossa and manifested a lesion of the nerve, ie, edema and hyperemia in the geniculate ganglion, meatal foramen, and internal auditory canal. A discussion of pathogenesis and a literature review is included.

In a patient with a multichannel cochlear implant, it was possible to demonstrate stapedial reflex contraction to intracochlear electrical stimulation. Using a standard immittance measurement technique, characteristics of the electrically evoked reflex were compared to analogous characteristics of the acoustically evoked reflex. Latency-intensity functions were similar for the two modes of excitation, but reflex waveform morphology and amplitude growth functions were different. The effects of electrode position and electrode spacing were of particular interest. In our patient, neither position nor spacing affected onset latency. Both electrode position and electrode spacing did, however, affect reflex amplitude. As position moved from base to apex, reflex amplitude increased systematically and substantially. Although we have reported amplitude results in suprathreshold current level, we also found the same relationship across electrode position for stimulation at constant current level. Reflex amplitude by electrode spacing was also affected. The widest spacing (3 mm) produced the largest reflex amplitude, and the narrowest spacing (1.5 mm) produced the smallest amplitude. The spacing effect, however, showed a strong interaction with electrode position, being greatest at the apical position and least at the basal position.