Interacoustics TRV chair, Instructions For Use Manual

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D-0125111-A – 2020/04
TRV chair – Instructions for Use - EN Page 30
The limit stop is now in the working position and the Sémont maneuver can commence.
The secondary frame is rotated to an angle of 45º away from the affected side and locked in this
position.
The primary frame can then be released for smooth rotation.
Hold the primary frame by the carrying handle, standing on the side towards which the chair is to
be tilted (affected side). Once the primary frame has been released, the patient will be rotated
over the affected side into 45º below the horizontal plane, patient’s face towards the ceiling. This
often triggers vertigo, accompanied by a nystagmus typical of an affection of the posterior canal
(up beating w. torsional component towards affected ear).
After a pause of about one minute, the potentiated Sémont maneuver can be performed at 270°
with brisk deceleration against the purpose-designed limit stop.
With deceleration maneuvers, the rotational speed on the horizontal axis should be around 10 to
15 rpm, which is approximately two to three seconds from start to finish at the limit stop.
Excessive rotational speed is to be avoided: it does not increase therapeutic efficacy, and it only
causes premature wear on the equipment as well as reduced tolerance in the patient. A liberatory
nystagmus may be observed and the patient is left for about one minute in this position, then
elevated to the upright position.
At this point, the nystagmus may re-occur, accompanying the transition of otoconia through the
crus communis, often with a predominant inferior vertical component.