Abstract | OBJECTIVES/HYPOTHESIS: To evaluate vestibular function in patients with the mitochondrial A3243G mutation. STUDY DESIGN: Data from patients with the A3243G mutation attending an academic tertiary referral center were prospectively recorded. METHODS: The clinical histories of 13 unrelated patients with the mitochondrial A3243G mutation (six mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes; and seven maternally inherited diabetes and deafness) were recorded, in particular their history of vestibular symptoms. Vestibular examinations including caloric testing and vestibular evoked myogenic potentials in response to air-conducted sound (ACS-VEMPs) were performed. In seven patients who showed abnormal ACS-VEMP, VEMP in response to galvanic stimuli (galvanic-VEMP) were also recorded. RESULTS: Eleven of the 13 patients had vestibular symptoms. The age of onset of vestibular symptoms was significantly later than the ages of onset of hearing loss and diabetes mellitus (P < .05). Ten of the 13 patients showed abnormal caloric responses, whereas 12 patients showed abnormal ACS-VEMPs on one or both sides. All of the seven patients who underwent galvanic-VEMP testing showed normal responses. CONCLUSIONS: The A3243G mutation is associated with vestibular dysfunction involving both the superior and inferior vestibular nerve systems. Furthermore, our results from galvanic-VEMP testing suggests that a labyrinthine lesion is primarily responsible for the symptoms of vestibular dysfunction.
|
Authors | Shinichi Iwasaki, Naoya Egami, Chisato Fujimoto, Yasuhiro Chihara, Munetaka Ushio, Akinori Kashio, Tatsuya Yamasoba |
Journal | The Laryngoscope
(Laryngoscope)
Vol. 121
Issue 8
Pg. 1821-4
(Aug 2011)
ISSN: 1531-4995 [Electronic] United States |
PMID | 21792976
(Publication Type: Journal Article)
|
Copyright | Copyright © 2011 The American Laryngological, Rhinological, and Otological Society, Inc. |
Chemical References |
|
Topics |
- Acoustic Stimulation
- Adult
- Auditory Threshold
- Body Surface Potential Mapping
- Caloric Tests
- Cochlea
(physiopathology)
- DNA, Mitochondrial
(genetics)
- Diabetes Complications
- Electromyography
- Female
- Hearing Loss, Sensorineural
(genetics, physiopathology)
- Humans
- MELAS Syndrome
(genetics, physiopathology)
- Male
- Middle Aged
- Mitochondrial Diseases
(genetics, physiopathology)
- Point Mutation
- Vestibular Diseases
(genetics, physiopathology)
- Vestibular Evoked Myogenic Potentials
- Vestibular Function Tests
|