Abstract
This study describes 15 special cases of sudden deafness with further progression of hearing loss after initial examination in our clinic. The authors examined the otological, audiological and laboratory findings of those patients, including family and past history, Results were as follows;
1. The patients consisted of 5 males and 10 females, with an average age of 41 years.
2. Audiological findings with respect to hearing loss were variable.
3. Hearing loss progressed after the initial examination and reached a maximum at about 7 days after the onset of initial hearing loss.
4. Patients could be divided into four groups on the basis of increased hearing loss at various sound frequencies;
(1) increasing hearing loss in the low tone range,
(2) in the middle tone range,
(3) in the low-middle tone range,
(4) in all ranges of tones.
The third group was greatest in number.
5. The progression of hearing loss could be classified into 3 types according to the mode of increasing hearing loss.
Type I hearing loss was characterized by rapid progression after increased hearing loss had begun.
Type II was characterized by slow progression.
Type III was characterized by progression starting after 1 to 3 stable days. These results were discussed from the perspective of clinical audiology.
