Role Of High Resolution Computed Tomography In Evaluation Of Pathologies Of Temporal Bone

Abstract

BACKGROUND & OBJECTIVES Pathology of the ear is one of the most common reasons of visiting an otolaryngologist, with inflammatory conditions being predominant. The evaluation and diagnosis of complex lesions of the temporal bone is challenging task both for the radiologist as well as otolaryngologist. Earlier, clinical examination was used along with X- rays for the diagnosis. However with increasing prevalence of infective pathologies of ear, this approach proved inadequate. Complicated anatomical structure of middle and inner ear makes radiographic assessment of temporal bone difficult. CT has the advantage of producing images with higher contrast and a better spatial resolution. High resolution CT (HRCT) images are obtained with thin sections and special bony algorithm for high details. HRCT, a modification of routine CT, provides a direct visual window into the temporal bone providing minute structural details. It is an excellent tool for evaluation of the middle ear diseases and adjacent bone and has the advantage of being devoid of artifacts from superimposition of structures. HRCT also helps in accurate assessment of pathology prior to surgical exploration regarding location, extent and complication of the disease. This study is undertaken to study congenital anomalies, infective, trauma and and neoplastic pathologies of the temporal bone along with their complications on HRCT. AIMS & OBJECTIVES OF THE STUDY: 1. To study the extent of middle ear infections and their complications. 2. To study the congenital anomalies of the ear according to compartment involvement. 3. To evaluate changes in temporal bone due to trauma. 4. To characterize neoplasms and assess their extent of involvement in temporal bone. SOURCE OF DATA: Data for the study is collected from the patients attending/referred to the Radiology department of B.L.D.E.U’s Shri.B. M. Patil Medical College, Hospital and Research Centre, Vijayapur who fulfill the inclusion criteria. METHOD OF COLLECTION OF DATA: The study was done on patients, who visited the Department of Radio Diagnosis during the period from OCTOBER 2015 to MAY 2017. Consent taken for each case. RESULT: In our study series of 48 cases, we got 26 cases of infective etiology, 12 cases of traumatic etiology, 8 cases of neoplasms and 2 cases of congenital anomalies. Majority of the temporal bone pathologies included infections (72%). Among infective conditions, cholestetoma was commonest with more preponderance in young age. Trauma accounted for 14% followed by neoplasms (10%) and congenital anomalies (6%). INTERPRETATION: HRCT is a revolutionary imaging modality that helps in evaluating the normal anatomical structures, normal variants, distribution features, localization and assessing the extent of various pathologies affecting the temporal bone.