The association between semicircular canal dehiscence and Chiari type I malformation.
OBJECTIVE
To investigate the association between semicircular canal dehiscence (SCD) and Chiari type I malformation (CM-I).


METHODS
Retrospective case series.


METHODS
Military tertiary referral center.


METHODS
Adult patients with SCD.


METHODS
Review of records of patients diagnosed as having SCD for the radiologic diagnosis of CM-I and presenting symptoms.


METHODS
The prevalence of CM-I among patients with SCD and the presenting symptoms of patients with SCD with and without a coexistent CM-I.


RESULTS
Of 32 patients diagnosed as having SCD, 30 underwent magnetic resonance imaging of the brain. Seven patients (23%; 95% confidence interval [CI], 12%-41%) were found to have a CM-I. Chiari type I malformation was associated with superior SCD in 3 of 26 patients (12%; 95% CI, 3%-30%). Of 10 patients with bilateral superior SCD, 2 (20%; 95% CI, 5%-52%) had a CM-I. Five of 6 patients (83%; 95% CI, 42%-99%) had a CM-I with unilateral or bilateral posterior SCD. Twenty-nine records were reviewed for presenting symptoms, and no significant difference was observed between patients with SCD alone and those with an associated CM-I (P = .09-.64).


CONCLUSIONS
Among patients with SCD, the prevalence of CM-I is elevated. This association is especially marked in patients with posterior SCD. This finding suggests a relationship between CM-I and SCD, particularly with posterior SCD.
Department of Otolaryngology-Head and Neck Surgery, Naval Medical Center Portsmouth, 620 John Paul Jones Cir, Portsmouth, VA 23708-2197, USA. Jeffery.Kuhn@med.navy.mil
Jeffery J
JJ
Kuhn
Timothy
T
Clenney
D000328:Adult; D001139:Arnold-Chiari Malformation / Q000473:pathology*; D001299:Audiometry; D001844:Bone Conduction / Q000502:physiology; D005071:Evoked Potentials / Q000502:physiology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D012189:Retrospective Studies; D012665:Semicircular Canals / Q000000981:diagnostic imaging* / Q000503:physiopathology; D014057:Tomography, X-Ray Computed; D015837:Vestibular Diseases / Q000000981:diagnostic imaging* / Q000503:physiopathology; D014724:Vestibular Function Tests