<prompt> What is true in case of perforation of pars flaccida -CSOM is a rare causeAssociated with cholesteatomaUsually due to traumaAll of the above  <response>: Tympanic membrane can be divided in 2 parts:Parstensa : It forms most of the tympanic membrane. Its periphery is thickened to form fibro cartilaginous ring called as annulus tympanicus.Pars Falccida : It is situated above the lateral process of malleus between the notch of Rivinus and the anterior and posterior malleolar fold.Ref. Dhingra 6e p59, 5e p 78 