Unsafe perforation of tympanic membrane is
Ans. b (Marginal).(Ref. Diseases of ENT, PL Dhingra, 2nd ed., 71, 3rd ed., 99)# Tubotympanic disease or central perforation remains localized to mucosa and that too mostly to anterioinferior part of middle ear cavity.# While atticoantral type or marginal or unsafe otitis media involves posteriosuperior part of middle ear cleft (attic, antrum, posterior tympanum and mastoid) and is associated with cholesteatoma, which due to its bone eroding property causes risk of serious complications and hence called unsafe or dangerous type.# Attic and posterosuperior marginal perforations are in dangerous type of CSOM and are often associated with cholesteatoma while central perforation is considered safe, as cholesteatoma is usually not associated with them.
Central
Marginal
Paracentral
Multiple central
CSOM and its Complications