<prompt> A girl for chronic ear discharge, pain on ocular movements and veigo underwent mastoidectomy. There was no relief post-operatively and continuous purulent ear discharge was seen. Patient also had sensorineural hearing loss. The most probable diagnosis would he:Suppurative labyrinthitisApical petrositisSerous labyrinthitisLateral sinus thrombophlebitis  <response>: Ans. b. Apical petrositis 