Following are the laboratory tests for the diagnosis of vestibular dysfunction except -

Gelle's test is a bone conduction test. It is performed by placing a vibrating fork on the mastoid while changes in air pressure in the ear canal are brought about by siegel's speculum. It is positive in normal person and in those with sensory neural hearing loss. It is negative when ossicular chain is fixed. Ref: Dhingra 7e pg 24.