<prompt> Glomus tumor invading the veical pa of carotid canal. It isType BType CIType C2Type C3  <response>: Ans. is c i.e., Type C2 Fisch classification The Fisch classification of glomus tumors is based on extension of the tumor to surrounding anatomic structures and is closely related to moality and morbidity. Type A :- Limited to middle ear cleft glomus tympanicum. Type B :- Limited to tympanomastoid area with no involvement of infralabyrinthine compament. Type C :- Involving infralabrinthine compament extending upto petrous apex Type C1 :- Limited involvement of veical poion of carotid canal Type C2 :-Invading veical poion of carotid canal Type C3 :-Invasion of horizontal poion of carotid canal Type D Intracranial extension Type D1 Intracranial extension 2 cm in diameter Type D2 :-Intracranial extension 2 cm in diameter 