Cochlear dysfunction in patients with mitochondrial myopathy.
The present study investigates cochlear function in a group of 11 patients suffering from mitochondrial myopathy with normal or near normal audiometric pure tone thresholds, in most of whom diagnosis was histologically confirmed. A complete ENT, neurologic and audiological work-up, including transiently evoked otoacoustic emissions, was performed in all patients in order to estimate cochlear function. Compared to control subjects, most patients had absent otoacoustic emissions (OAE) in spite of normal hearing, indicating cochlear dysfunction. These findings suggest that subclinical involvement of the cochlea is quite common in patients with mitochondrial myopathy. Damage of the cochlea can be explained on the grounds of its increased metabolic rate, resulting in failure of the stria vascularis and the outer hair cells. Otoacoustic emissions might provide a useful tool in the clinical work-up and follow-up of these patients.
Korres
Stavros
S
ENT Clinic of Athens National University, Ippokration Hospital, 23 Achaion Street, Agia Paraskevi, GR-18536 Athens, Greece. dbalats@hotmail.com
Balatsouras
Dimitrios
D
Manta
Panagiota
P
Economou
Constantinos
C
Yiotakis
Ioannis
I
Adamopoulos
Georgios
G
D000328:Adult; D000368:Aged; D001300:Audiometry, Evoked Response; D001301:Audiometry, Pure-Tone; D001309:Auditory Threshold; D015834:Cochlear Diseases / Q000209:etiology* / Q000503:physiopathology; D016057:Evoked Potentials, Auditory, Brain Stem; D005260:Female; D006311:Hearing Disorders / Q000209:etiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D017240:Mitochondrial Myopathies / Q000150:complications* / Q000503:physiopathology; D017084:Otoacoustic Emissions, Spontaneous; D015203:Reproducibility of Results