<prompt> Galles test is used for ?OtosclerosisJuvenile angiofibromaNasal polypNone  <response>: Ans. is a i.e., Otosclerosis Gelles test It is a bone conduction test and examines the effect of increased air pressure in ear canal on hearing. Increased air pressure in ear canal by Siegles speculum pushes the tympanic membrane and ossicles inwards which raises the intralabyrinthine pressure and causes immobility of basilar membrane and decreased hearing. However, if ear ossicles are already fixed or disconnected, the pressure cannot be transfered to inner ear No change in hearing in this situation. Base of vibrating tuning fork is placed on mastoid process and air pressure in ear canal increased by Siegles speculum. Interpretation are : - Positive Gelles decreased hearing on increased pressure- Normal or sensorineural hearing loss. h Negative Gelles No effect of pressure change in hearing - Disconnected or fixed ossicular chain. 