A study of middle ear reconstruction, the degree of functional restoration and causes of graft failure following chronic ear disease

Abstract

Aims and objectivesTo determine the results of various types of tympano-ossiculoplasties and the degree of functional restoration following surgery. Materials and methodsThis prospective study comprises 51 consecutive patients with chronic suppurative otitis media (CSOM) – tubotympanic disease (TTD) and atticoantral disease (AAD), who presented to the academic department of Otorhinolaryngology – Head & Neck Surgery, in a tertiary care hospital in South India. All patients underwent a thorough examination and appropriate investigations. Eustachian tube function (ETF) was assessed preoperatively by methylene blue dye test and saccharin test. The size of the mastoids was measured by using a graph paper, on which the X-ray film of the mastoid taken in the lateral oblique view (Law’s view) was superimposed. Patients with CSOM (TTD) with less than 3months of dry ear and small size mastoids on X-ray were subjected to cortical mastoidectomy and type I tympanoplasty; whereas patients with dry ear more than 3months underwent type I tympanoplasty alone. Type III tympanoplasty was carried out in those with erosion of incus/malleus by placing temporalis fascia over the stapes superstructure. Patients with AAD underwent modified radical mastoidectomy (MRM) and ossicular reconstruction was carried out depending on the remnant of the ossicles. Partial Ossicular Replacement Prosthesis (PORP) made of plastipore was used for Austin’s type b ossiculoplasty; while Plastipore/Gold was used as Total Ossicular Replacement Prosthesis (TORP) in type d ossiculoplasty. Patients were reviewed after 15days, 1 and 3months post-operatively for a clinico-audiological assessment of the operated ear to evaluate the graft status and hearing improvement. The postoperative audiograms were recorded on the 2nd and 3rd visit. Results and observationsOf the 51 patients with CSOM; 37 had TTD and 14 had AAD. Of the 37 patients with TTD, 35 patients had normal ETF and 2 of them had partial dysfunction. With normal ETF, the graft uptake rate was 80% compared to partial ETF which had only 50%. Patients with large and medium size mastoids had 89% of graft uptake. Patients with small and medium size perforations had 100% graft uptake; whereas large and subtotal perforations had 75% and 71.43% respectively. A total number of 34 tympanoplasties and 17 ossiculoplasties were done. Of these; 29 were type I and 5 were of type III. Out of 17 ossiculoplasties, 3 were type b and 14 cases were of type d. We used 7 Gold and 7 Plastipore TORP for the type d ossiculoplasty and PORP in 3 of the cases. Using temporal fascia as graft material 34 patients underwent tympanoplasty in whom the graft uptake was 79.41%, while 17 patients underwent ossiculoplasty using temporalis fascia as graft, the graft uptake was 88.23%. Tympanoplasty done for small and medium size perforations had 100% hearing improvement with A–B gap <20dB but patients who had large or subtotal perforations had 80% and 67% respectively. Hearing improvement to an A–B gap <20dB was noted in 91% and 60% following type I and type III tympanoplasty respectively. Hearing improvement to an A–B gap <20dB was noted in all the cases of type b ossiculoplasty and with type d ossiculoplasty (42%). ConclusionPatients with normal Eustachian tube function, large and medium size mastoids, small and medium size perforations of the tympanic membrane would have a good rate of graft uptake with tympano-ossiculoplasties thereby returning to normal hearing postoperatively.