Cochlear hydrops analysis masking procedure results in patients with unilateral Ménière's disease.

OBJECTIVE

To investigate the usefulness of the cochlear hydrops analysis masking procedure (CHAMP) as an additional diagnostic test in patients with definite unilateral Ménière's disease.

STUDY

DESIGN

Prospective validation study for a diagnostic test.

SETTING

Tertiary referral center.

PATIENTS: Subjects (n = 22) with definite unilateral Ménière's disease.

INTERVENTIONS: The CHAMP test was performed in both ears of the patients.

MAIN OUTCOME MEASURE: Difference in latency delay between the affected and the unaffected ears.

RESULTS

In 20 subjects, latency delays could be measured in both ears. The mean latency delay for the affected ears (0.55 ms; standard error, 0.12 ms) differs significantly from that for the unaffected ears (3.36 ms; standard error, 0.43 ms). With the standard criterion to separate ears with an abnormally short delay (<0.3 ms) from ears with a normal delay, in only 7 of 20 affected ears, an abnormally short delay was measured. All 33 other ears produced a normal delay. With the less than 0.3 ms criterion and including the ears in which no delay could be measured, the sensitivity of the CHAMP is 32% (7/22). Pooling CHAMP latency delays for 235 ears from this work and the literature yielded 2 clearly distinct distributions, with a separation at 2 ms. Defining abnormal delays as shorter than 2 ms gave an abnormal delay for 18 of 20 affected ears and for 7 of 20 unaffected ears.

CONCLUSION

Abnormal latency delays for CHAMP are delays shorter than 2 ms. Earlier results with CHAMP should be reconsidered using this criterion, instead of 0.3 ms.