Modern surgical treatment of otosclerosis - Helda - Helsinki.fi

Results and comments
A final follow-up visit was held 3-4 months postoperatively. Only one of the
aforementioned patients still suffered from vestibular symptoms. Two patients (11%) had
spontaneous horizontal nystagmus, one beating towards the operated ear with an SPV of
1.3 º/s and the other beating away from the operated ear with an SPV of 2.7 º/s. The latter
also had HSN directed towards the operated ear. It evolved postoperatively with an SPV
of 13.3-17.8-7.3 º/s. Another patient had HSN beating away from the ear, which was
operated on, diminishing SPV to 6.6 º/s. The number of patients that had vertically
oriented nystagmus was equal when comparing pre- and postoperative results.
Postoperatively, there was no change in the direction of the nystagmus in any patient.
Torsional nystagmus was not found pre- or postoperatively.
Three (33%) of the patients suffering from vestibular symptoms during the first
postoperative week had had previous middle ear surgery on the other ear due to
otosclerosis. Two of the four patients whose planned stapedotomy was converted to a
stapedectomy had vestibular symptoms one week after the operation, in one case lasting
throughout the study period. However, neither the second ear operation or stapedectomy
for technical reasons (p=0.06) nor the use of a laser instead of a micro-drill (p=0.07)
presented a statistically significant risk for experiencing postoperative vertigo.
Audiological measurements were done 3-4 months postoperatively. The postoperative
average for the AB-GAP diminished to 6 dB (range 0-31 dB) from a preoperative value of
25 dB (range 7-47 dB). The average overclosure was 4 dB (range -7-18 dB). A
postoperative AB-GAP under 10 dB was achieved in 76% (25/33) and a AB-GAP under
20 dB in 94% (31/33) of patients.
No significant correlation between vertigo and type of nystagmus was found. Vestibular
symptoms seem to be more prevalent in a second ear operation and with stapedectomy,
but the difference was not statistically significant. Vestibular symptoms were mild and
usually short-lasting, consistent with previous reports.
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