Interacoustics TRV chair, Instructions For Use Manual

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D-0125111-A – 2020/04
TRV chair – Instructions for Use - EN Page 27
Alternative procedure to examine the lateral SCCs:
•
Press the foot switch to release the magnetic lock holding the primary frame
• The patient is brought into the supine position, nose towards the ceiling
• Press the foot switch to lock the primary frame. Check that the lock engages correctly and
that the green indicator light switches off
•
Turn the patient 90° towards one side and 180° to the other side - then again 180° back
towards the initial side, until the nature and characteristics of the horizontal positional
nystagmus are sufficiently documented to determine which side needs treatment.
•
The examiner may refer to Ewald’s 2
nd
law (Paganni & Mc Clure maneuver) or to the table
below to reach the correct diagnosis: If the horizontal nystagmus is beating towards the
undermost ear (geotropic form), the side that needs to be treated is the side that elicits the
strongest positional nystagmus when pointed towards the floor.
•
If the horizontal nystagmus is beating towards the ceiling (apo geotropic form), the examiner
must determine on which side the apo geotropic nystagmus is strongest – if for example this
is when the left ear is down, the BPPV is in the right horizontal canal