2.9% to 8.1% of patients with nonimproving or progressive issues may have AN

[annamaria]

I remember someone asking in this Forum: "If I have asymmetric hearing loss/issues, what is the probability I have AN?". Here is the answer from a brand-new paper: 2.9% to 8.1% of patients.

Annamaria

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Ann Otol Rhinol Laryngol. 2010 Sep;119(9):615-8.

Prevalence of acoustic neuroma associated with each configuration of pure tone audiogram in patients with asymmetric sensorineural hearing loss.
Suzuki M, Hashimoto S, Kano S, Okitsu T.

Dept of Otolaryngology, Teikyo University School of Medicine, 2-11-1 Kaga, Itabashi-ku, Tokyo 173-8605, Japan.

Abstract

OBJECTIVES: The criteria have not yet been established for identifying the configuration of a pure tone audiogram constituting abnormal results that warrant further investigation. The purpose of this study was to determine the prevalence of acoustic neuroma associated with each configuration of the pure tone audiogram in patients with asymmetric sensorineural hearing loss (SNHL).

METHODS: We performed a retrospective chart review of 500 patients 15 years of age or older who had asymmetric SNHL and had undergone magnetic resonance imaging.

RESULTS: The prevalence of acoustic neuroma in these patients was 2.6% (13 of 500). The prevalence of acoustic neuroma in each audiometric configuration was as follows: 7.1% (3 of 42) for a basin-shaped loss (odds ratio [OR] versus overall prevalence, 2.88; p = 0.23; 95% confidence interval [CI], 0.79 to 10.54), 4.7% (5 of 107) for a flat loss, 3.4% (2 of 58) for total deafness, 2.9% (1 of 34) for a high-frequency sloping audiogram, and 2.5% (2 of 81) for a high-frequency steep audiogram. The prevalence in patients with nonimproving idiopathic sudden deafness was 8.1% (OR, 3.29; p = 0.06; 95% CI, 1.13 to 9.55).

CONCLUSIONS: In conclusion, 2.9% to 8.1% of patients with a characteristic configuration of the pure tone audiogram and symptoms of nonimproving or progressive idiopathic sudden deafness may have acoustic neuroma.

[HeadCase2]

interesting

[PaulW]

I think it is important to note that these numbers are based on
Asymmetric sensorneural hearing loss.
It must also be progressive and non improving.

The most common reasons causing single sided hearing loss are WAX, middle ear infection, otosclerosis, accidents.
These not sensorineural.

Due to the age when most AN's get diagnosed I would suspect the incidence of AN is higher in the 40's - 50's age group.
But less in the sub 40's and over 65's where other forms of sensorineural hearing loss are more common.

[Toadlee]

Thanks-
That's just what I was looking for. I figured it would be higher than overall incidence. I'm glad I pressed for the MRI. My Ent office staff were pretty slow in getting me the referral, and I felt a little pushy, but now I feel it was good health practice. They've  ruled out all the obvious (earwax, infection, etc.) but I did hit my head last year. Didn't think I'd shook loose any screws. Anyone know, would that be sensory neural or conductive?

Toadlee