Why Do We Not Need CT in Patients Who Undergo Type I Tympanoplasty?

Abstract

Introduction Since its advent in the 1980s, high-resolution computed tomography (HRCT) of the temporal bone has played an important role in the evaluation of chronic otitis media (COM) (1). It provides a detailed assessment of complex bony structures of the middle ear and mastoid cavity; thus, surgeons can visualize the extent of disease, status of the ossicular chain, presence of bony erosion, or existing cholesteatoma prior to surgery (2, 3). HRCT has gained wide acceptance in the diagnostic workup of suppurative COM. Most ear surgeons order HRCT to make a rational operative plan, especially in the presence of symptoms, such as refractory otorrhea with bad odor, epithelial debris at retraction pockets, and defects in bony walls of the middle ear. Previous studies showed contradictory results with regard to the sensitivity and specificity of the preoperative HRCT scan. A preoperative HRCT scan was suggested to underestimate the actual pathology in the middle ear and was unreliable in some of the articles (4, 5). The study group in those studies included patients with diverse clinical findings and different surgical plans, including tympanomastoidectomy or open cavity mastoidectomy. This diversity of patient groups may cause certain shortcomings in the assessment of the necessity for preoperative HRCT. It is a common belief that preoperative HRCT is not necessary in patients with dry perforation and mild hearing loss in the absence of destructive middle ear pathology. But, unfortunately, few surgeons insist on ordering HRCT prior to tympanoplasty in their daily practice. This malpractice leads patients to exposure to avoidable radiation. Although there is almost a consensus that HRCT prior to surgery is unnecessary in these patients, it has not been proven yet objectively. Thus, we aimed to show the lack of necessity of preoperative HRCT by assessing its predictive value in patients who undergo type I tympanoplasty. Methods This retrospective study with data collection was conducted at department of Otolaryngology in Uludag University. The study group was selected from patients who underwent tympanoplasty with or without ossicular reconstruction with a diagnosis of chronic otitis media between August 2010 and February 2013. The inclusion criteria were as follows: i) presence of tympanic membrane perforation, ii) no refractory ear drainage, iii) dry ear for at least 3 months, iv) no cholesteatoma on microotoscopic examination, and v) no bony erosion or retraction pocket. At our institution, we certainly do not order preoperative CT in patients who undergo type I tympanoplasty. However, we have other patients who were referred by other colleagues for surgery with a prior HRCT. We had 43 patients who fulfilled the aforementioned criteria with a prior HRCT in the study group. The mean age of the study group was 32.44±13.78 77