[Benign paroxysmal positional vertigo of the horizontal canal]

The benign positional vertigo of the horizontal canal seems to find its origins in a canalolithiasis. The diagnosis is usually easy when its characteristics are perfectly known. A horizontal nystagmus does not always mean that the vertigo is of a central origin. This canal is exclusively connected, via the brainstem, to the external and internal oculomotor muscles so that the movement obtained by its stimulation can only be horizontal! This is quite different from what is obtained for the posterior canal, which is connected to various oculomotor muscles. Specific therapeutic maneuvers have to be carried out to be efficient: if properly performed, the otoconias, heavy particles sensitive to gravity, are easily mobilized. This paper describes the pathophysiology of the positional vertigo of the horizontal canal, diagnosis of its two presentations, and therapeutic possibilities.