Magnetic resonance imaging in the search for retrocochlear pathology.

OBJECTIVES: The purpose of this study is to evaluate the incidence of retrocochlear pathologic conditions that may be seen with full, contrast-enhanced magnetic resonance imaging of the brain, relative to more limited studies of the internal auditory canals (IACs) in patients with unilateral hearing loss or tinnitus with or without dizziness. METHODS: A retrospective study was performed on all patients who had a magnetic resonance imaging of the brain and otologic symptoms over a 7-year period. RESULTS: Abnormalities were found in 11 of 128 patients with only auditory symptoms and in 63 of 282 patients with auditory symptoms and/or dizziness (P = 0.005). Treatable lesions may not have been identified with a limited IAC study in 3 of 128 patients with only unilateral auditory symptoms, and 21 of 282 patients with dizziness (P = 0.045). CONCLUSIONS: Limited MRI of the IACs may serve as an adequate screening test for retrocochlear pathologic conditions in patients with unilateral auditory symptoms and no dizziness.

Stapedectomy vs stapedotomy. Do you really need a laser?

OBJECTIVE: To compare the effectiveness of different techniques of stapes surgery in improving the hearing of individuals with otosclerosis. METHODS AND DESIGN: Large and small fenestra techniques, as well as the instrument used to make the fenestra (drill or laser), were compared with regard to effectiveness and rate of side effects. The charts of 875 patients who underwent primary stapedectomies performed by members of the House Ear Clinic, Los Angeles, Calif, were reviewed. Patients who underwent stapedectomy for reasons other than otosclerosis and those with inadequate post-operative bone conduction threshold data were excluded. A group of 550 patients met the criteria. This group was broken into categories depending on the technique of stapedectomy and the instrument used to create the fenestra. The techniques were then compared using air-bone gap closure at different frequencies, pure tone average, and the rate of significant side effects. RESULTS: The study indicated that small fenestra stapedotomy and large fenestra techniques have similar rates of closure of the air-bone gap. Small fenestra stapedotomy has a slightly lower rate of postoperative sensorineural hearing loss, especially at higher frequencies. With regard to the small fenestra technique, there was no significant difference in either postoperative air-bone gap closure or postoperative sensorineural hearing loss, regardless of whether the fenestra was created by laser or microdrill. CONCLUSIONS: While we did find a statistically significant difference between the large and small fenestra techniques in postoperative sensorineural hearing loss at higher frequency, the difference is small and is probably not clinically significant. Therefore, we find that similar good results can be obtained by the experienced surgeon using either the large or small fenestra technique. Similarly, we found the laser and microdrill to be equally safe and effective in the creation of the fenestra.