Measurement Of The Precise Cochlear Reserve In Otosclerosis Value Of Speech Weber Test

Abstract

The authors think that in otosclerosis surgery the accurate measurement of cochlear function must be made according to 4 local factors, to which must be added a 5th, general one.

The pure-tone audiogram gives the diagnosis of the stage of deafness. Accurate bone conduction (BC) must of course be researched with a contralateral narrow-band masking when there is the slightest difference between 2 air-conduction (AC) diagrams, as well as between the 2 BC diagrams.

Speech audiometry gives the functional value of the ear. It must be done in AC and BC; the authors insist on the value of the speech Weber test.

The Carhart notch must always be taken into account in forecasting the postoperative result; it explains why part of postoperative BC rises above preoperative BC.

A progressive integration of hearing occurs slowly, generally in one year or more, under the influence of treatment to support the cochlea.

Finally, a general, cardiovascular, factor must be added to the 4 local factors for measurement of the cochlear reserve. But the difficulty of appreciating the respective imporance of each of these factors makes the exact evaluation of the definitive postoperative functional result a little imprecise. This is why the authors propose their own very simple technique for the measurement of cochlear reserve in otosclerosis. It consists of the speech technique for the measurment of cochlear reserve in otosclerosis. It consists of the speech Weber test, which automatically indicates, by the direction of lateralisation, the ear to be operated on first, the test-curve permits forcast of the postoperative functional level for the ear towards which the test is lateralised or the level of the 2 ears when it is unlateralised.

The authors explain the technique used, and support the results with 5 exaples of cases most frequently encountered in otosclerosis surgery.

Key Words:

• Air-conduction audiometry
• Bone-conduction audiometry
• Speech audiometry
• Carhart notch
• Otosclerosis surgery