<prompt> Endolymphatic decompression is done in:TinnitusAcoustic neuromaMenieres diseasePerilymph fistula  <response>: c Menieres diseaseRef. Cummings, 6th ed., 2559Menieres disease being characterised by endolymphatic hydrops so here endolymphatic sac decompression is done when the medical management fails.Tinnitus is treated as per the underlying cause.Treatment modality of Acoustic neuroma is surgical excision.Perilymph fistula is repaired by grafting the fistula. 