Background: Otosclerosis is a heritable disease affecting the otic capsule.
Its genetics have been studied since the 19th century, but several issues
remain controversial.
Objective: The goals of this study were to assess the prevalence of sporadi
c and familial forms of otosclerosis in a population of otosclerotic patien
ts and to compare the radiologic findings between both groups.
Study Design and Setting: This retrospective study was conducted in a singl
e institution.
Patients: This study included 211 patients operated on for otosclerosis.
Main Outcome Measures: Clinical data, including pure tone audiograms, were
available from patients' charts. A questionnaire assessing family history o
f otosclerosis and deafness was mailed to the otosclerotic patients. A rela
tive was considered otosclerotic if surgery confirmed the disease. The fami
ly history was correlated with the computed tomography results. This examin
ation was performed before surgery in all patients.
Results: A family history of otosclerosis was found in 24.2% of the patient
s. The radiologic findings differed between patients with a sporadic form o
f otosclerosis and those with a familial form. The lesions were more often
detectable, bilateral, and severe in the familial forms (p < 0.05).
Conclusion: These findings lead to the assumption that fenestral radiologic
otosclerosis occurs more in sporadic forms, whereas more extensive lesions
on computed tomography seem to indicate the familial forms. Hereditary for
ms demonstrated to be familial seem to lead to more severe disease. The sea
rch for a genome locus of otosclerosis may be enlightened by these findings
.