Tympanic membrane retraction
The eardrum comprises two parts , the pars tensa , which is the main part of the eardrum , and the pars flaccida , which is a smaller part of the eardrum located above the pars tensa . 
<triplet> pars tensa <subj> pars flaccida <obj> has part <triplet> pars flaccida <subj> pars tensa <obj> part of