Study of outcome of tympanoplasties in relation to size and site of tympanic membrane perforation.

There are not many studies on the effect of the site and size of the perforation on the hearing loss. This study is set to investigate the relationship between the size and site of perforation and hearing loss. This study was carried out between September 2011 to September 2013, at a tertiary care centre during which 100 cases of chronic otitis media tubotympanic type having central perforation were selected. All patients underwent, tympanoplasty using temporalis fascia/cartilage graft, underlay technique with or without simple mastoidectomy/modified radical mastoidectomy and followed up for 3 months and evaluated for graft uptake and hearing improvement with respect to size and site of TM perforation. To measure the size of perforation intra-operatively, thin transparency sheet was used, on which a graph paper of 1 × 1 mm(2) size was printed. Significant relationship was observed between size and site of tympanic membrane perforation with hearing loss. Perforations which were involving all four quadrants (AS + AI + PS + PI) are having maximum residual perforations after the surgery. In relation with size, subtotal perforation were having more residual perforations postoperatively, followed by medium sized perforations. An inherent relationship noted between ossicular involvement and hearing loss, maximum average hearing loss was observed in those cases, where all three ossicles (malleus, incus & stapes) were involved, also more hearing loss was noted in posterior perforations.