Risk factors of tympanoplasties in long-term observation

The aim of the study was to evaluate risk factors influencing the results of tympanoplasties on the base of material taken from the Department of Otolaryngology and Laryngological Oncology Collegium Medicum of Nicolaus Copernicus University in Bydgoszcz between 2004-2009. In this period 98 operations were done. The time from operation to hearing examination was 3 to 7 years, mean 5,43. Tympanoplastic operation were divided according to Tos classification. Measuring hearing results, tonal audiometry was done and mean air bone gap on four frequencies was assesed (500, 1000, 2000, 3000 Hz), according to AAO-HNS guidelines (1995). This parameter was compared between groups separated according to risk factors, that could potentially affect the results. Those risk factors were: disfunction of the Eustechian tube, localisation and size of the perforation of the tympanic membrane, damage of the ossicles, the state of the mastoid process, the number of operations, the presence of the cholesteatoma or granulating tissue, chronic otitis media in the opposite ear, smoking cigarettes, mastoidectomy, canal wall down technique. The results were analysed using statistical test.

The most impotant risk factor affecting treatment's results (besides discharge from the ear) is damage of the ossicles, especially the malleus and stapes. Well done operation ensures good hearing results irrespectively of the presence of cholesteatoma or granulating tissue, and also in case of reoperation. For all types of tympanoplasties neither the localisation, nor the size of perforation do not influence on hearing results in long term observation.