Otosclerosis: incidence of positive findings on temporal bone computed tomography (TBCT) and audiometric correlation in Korean patients.
OBJECTIVE
To assess the incidence of otosclerotic foci identified by temporal bone computed tomography (TBCT) in Korean and to determine the correlation between the extent of otosclerotic foci and audiometric findings.


METHODS
Thirty-one patients (37 ears) who were surgically confirmed otosclerosis and underwent preoperative TBCT scan were included. Patients underwent pre- and postoperative audiometric evaluation and TBCT. The mean air conduction (AC) thresholds and bone conduction (BC) thresholds, air-bone gap (ABG), and the difference between pre- and postoperative ABGs were determined. Otosclerotic foci were identified by the presence of hypodense lesions near the fissula ante fenestram and the otic capsule in the TBCT. The areas with hypodense lesions and the density ratio of the otosclerotic foci were compared by pre- and postoperative audiometric parameters.


RESULTS
Hypodense lesions were identified by the TBCT in 27 out of 37 cases (73%). Fenestral types were found in 23 cases and combined fenestral and cochlear types in 4 cases. There was a significant correlation between the density ratio of the otospongiotic foci and the postoperative mean ABG (P=0.03). However, there was no correlation between the size of the hypodense area and any of the audiometric parameters tested (P>0.05).


CONCLUSIONS
The rate of positive TBCT findings for otosclerosis in our series was 73%. The extent of the hypodense lesion did not correlate with the preoperative hearing levels. However, the density ratio of the hypodense lesion influenced the surgical outcomes.
Min
Jin-Young
JY
Department of Otorhinolaryngology-Head and Neck Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
Chung
Won-Ho
WH
Lee
Woo Young
WY
Cho
Yang Sun
YS
Hong
Sung Hwa
SH
Kim
Hyoung Jin
HJ
Lee
Hyun-Seok
HS
D000293:Adolescent; D000328:Adult; D000368:Aged; D044466:Asian People / Q000706:statistics & numerical data*; D001301:Audiometry, Pure-Tone / Q000379:methods*; D001309:Auditory Threshold / Q000502:physiology; D001844:Bone Conduction / Q000502:physiology; D005260:Female; D006314:Hearing Loss, Conductive / Q000175:diagnosis / Q000453:epidemiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010040:Otosclerosis / Q000175:diagnosis* / Q000453:epidemiology* / Q000601:surgery; D011182:Postoperative Care; D011300:Preoperative Care; D056910:Republic of Korea / Q000453:epidemiology; D012189:Retrospective Studies; D012720:Severity of Illness Index; D013702:Temporal Lobe / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed; D055815:Young Adult