Keywords:Tinnitus, Pitch, Loudness, Hearing Loss
Objective: To study the pitch and loudness of tinnitus and to find minimal masking level.
Study Design: Descriptive analytical study.
Place and Duration of Study: This study was conducted at Combined Military Hospital Rawalpindi, the tertiary referral center for Pakistan Armed Forces from 1998 to 2001.
Patients and Methods: Patients with tinnitus were included in the study. Exclusion criterion was transient tinnitus settling on removal of offending agent like foreign body and not having tinnitus as major presenting feature. Patients were thoroughly interviewed and tinnitus card (questionnaire) was filled. Thorough general physical and Ear Nose Throat examination was carried out including relevant tests to elucidate any cochleovestibular pathology. All patients had pure tone audiometery and tinnitus testing and sophisticated investigations were carried out whenever indicated.
Results: Most patients of tinnitus were seen between age of 40 to 60 years and 76.6% patients were male. Hearing loss accompanied tinnitus in 90% patients and 53% patients had tinnitus of moderate intensity. Pitch match frequency of 4 kilohertz was seen in 25.3% while 29% patients had loudness match of tinnitus ranging from 55 to 70 decibel (dB). In vast majority (24%) minimal masking level ranged from 41 to 55 dB. Seventy nine percent patients had pitch match frequency at or around frequency of maximum hearing loss.
Conclusion: Tinnitus is seen predominantly among males and its frequency increases with age .It is usually of moderate intensity and is of high pitch which corresponds to frequency of maximum hearing loss. Pitch of tinnitus is not a good indicator of degree of annoyance while loudness match gives a good measure of annoyance. Minimal masking levels are at or around loudness match. Tinnitus in majority of patients is associated with mild to moderate degree of hearing loss.