High-Resolution Imaging of Temporal Bone

All patients underwent high-resolution computed tomography (HRCT) of the temporal bone in our hospital using a Philips Brilliance 64 CT scanner (Philips Medical Systems, Best, Netherlands) in a closed resting position. The imaging parameters were as follows: voltage, 120 kV; current, 200 mA; matrix, 512 × 512; and source image section thickness, 0.625 mm. Using a bone algorithm, the images were reconstructed in 1 mm slices in the axial, coronal, and sagittal planes. The window width was 4000 Hounsfield units (HU), and the window center was 700 HU. Two radiologists evaluated the external auditory canal (EAC), TMJ, and important middle and inner ear structures on HRCT images. An experienced otologist reviewed the cases, made a final diagnosis, and calculated the Jahrsdoerfer scores.