Abstract

Objective: There have been several efforts to elucidate the pathophysiology of the vestibular migraine (VM). But, there is no consistent result. This study was to identify the possible pathophysiology of VM by comparing vestibulo-ocular reflex (VOR) parameters between VM, and the tension type headache (TTH) patients. In addition, we compared VOR parameters between ictal and interictal period in the VM group.
Methods
Seventy eight patients were included: 44 having VM and 34 TTH. Three parameters (gain, asymmetry, and phase) of the horizontal VOR rotating at 60 degrees were measured. In 10 VM patients VOR parameters were obtained twice sequentially first in the ictal and second in the interictal period.
Results
Although the average of the VOR gain in VM group was lower than that of TTH group but there was no statistical significance. An asymmetry of the VOR was significantly higher in VM group. There were various changes in other VOR parameters between ictal and interictal periods with no consistent trends.
Conclusion
We could deduce that VM patients might have subclinical vestibular dysfunction from the reduced gain and increased asymmetry of the VOR in the interictal period. Dynamic changes of the VOR in the ictal period could be responsible for dizziness in VM patients, which are caused by the pathological alteration of the physiologic plasticity of the VOR.

• Keywords: Migraine;Vestibular function tests;Vestibulo-ocular reflex;