Article Access Statistics | | Viewed | 13039 | | Printed | 502 | | Emailed | 16 | | PDF Downloaded | 48 | | Comments | [Add] | | Cited by others | 7 | |
|

|
|
ARTICLE |
|
Year : 2011 | Volume
: 13
| Issue : 55 | Page : 423--431 |
Noise-induced tinnitus: A comparison between four clinical groups without apparent hearing loss
Ann-Cathrine Lindblad1, Björn Hagerman1, Ulf Rosenhall2
1 Department of Clinical Science, Intervention and Technology, Division of Ear, Nose and Throat Diseases, Unit of Technical and Experimental Audiology, Karolinska Institutet, Stockholm, Sweden 2 Department of Clinical Science, Intervention and Technology, Division of Ear, Nose and Throat Diseases, Karolinska Institutet and Department of Audiology, Karolinska University Hospital, Stockholm, Sweden
Correspondence Address:
Ann-Cathrine Lindblad Technical Audiology, KI, M45, Karolinska/Huddinge, SE-141 86 Stockholm Sweden
 Source of Support: Grants from Swedish Skandia Life, The Foundation
Tysta Skolan, the Federation of Hard of Hearing People (HRF), and the
Swedish Council for Working Life and Social Research, Conflict of Interest: None  | Check |
DOI: 10.4103/1463-1741.90310
The number of people with normal hearing thresholds seeking medical help for tinnitus and other hearing problems is increasing. For diagnostic purposes, existence/nonexistence of lesions or combinations of lesions in the inner ear not reflected in the audiogram was evaluated with advanced hearing tests applied to tinnitus patients with certain backgrounds, including noise exposure. For forty-six patients with pronounced tinnitus, and other symptoms, tentative diagnoses were established, including judgments of the influence of four causative factors: (1) acoustic trauma, (2) music, (3) suspected hereditary, and (4) nonauditory, for example, stress or muscular tension. They were analyzed with a test battery sensitive to lesions involving the outer hair cells, damage from impulse noise, and dysfunction of the efferent system. There were significant differences in test results between groups with individuals with the same most likely causative factor. Most patients claiming acoustic trauma had a specific type of result, 'hyper-PMTF' (psychoacoustical modulation transfer function), and abnormal test results of the efferent system. Everyone in the hereditary group had dysfunction of the efferent system. All patients working with music, except one, had some abnormality, but without specific pattern. The nonauditory group mostly had normal test results. The investigation shows that it is possible to diagnose minor cochlear lesions as well as dysfunction of the efferent system, which might be causing the tinnitus. Those abnormalities could not be detected with routine audiological tests. Malfunctioning caused by impulse noise is an obvious example of this. These findings facilitate choice of treatment, rehabilitation programs, and medicolegal decisions.
[FULL TEXT] [PDF]*
|