A head-tilt caloric test for evaluating the vertical semicircular canal function.

CONCLUSIONS

The caloric test with head-tilt can be used as a tool for assessing vertical canal function as an office procedure.

OBJECTIVE

Evaluation of vertical canal function.

PATIENTS AND METHODS

We provoked caloric response by cold water in the vertiginous patients in supine position. During the culmination of the response we rotated the head 45 degrees from the sagittal plane to place the posterior canal to earth-vertical. Thereafter we rotated the head 45 degrees to the opposite direction to place the anterior canal to earth-vertical. The eye movements were recorded by two-dimensional electronystagmography. The data collected from the examination of 100 ears with normal caloric response in horizontal component were analyzed.

RESULTS

The down-beating vertical component intensified when the posterior canal was placed to earth-vertical. The up-beating vertical component intensified when the anterior canal was placed to earth-vertical. These findings suggested that the vertical canals were functioning.