Three-dimensional analysis of pressure nystagmus in labyrinthine fistulae.

In this study we analysed pressure nystagmus three-dimensionally in subjects with labyrinthine fistulae. The fistulae were localized in the lateral canal in five patients, in the posterior canal in one patient and in both lateral and anterior canals in two patients. The eye velocities during the fistula test in patients with lateral canal fistula and in a patient with posterior canal fistula were closely aligned with the anatomical axes. On the other hand, pressure nystagmus in cases with fistulae of both the lateral and anterior canals were not aligned with the anatomical axes of the combination of both canals.