Multislice computed tomographic imaging in temporal bone dysplasia.

ABSTRACT

OBJECTIVES: To evaluate the impact of multislice computed tomographic (MSCT) imaging, a recently developed computed tomographic technique, on imaging of temporal bone malformations. STUDY DESIGN: Retrospective case review. SETTING: The study was performed at a tertiary referral center. PATIENTS High-resolution temporal bone studies of 168 consecutive patients were reviewed for various temporal bone malformations. MAIN OUTCOME MEASURES: Visualization of various dysplastic conditions of the temporal bone without the need for supplementary scan procedures or additional imaging techniques. INTERVENTION MSCT imaging was performed on a scanner with four detector rows by using the following parameters 120 kV, 50 mA/s, 0.5-mm slice thickness, 0.2-mm reconstruction increment, pitch factor of 0.75, and a field of view of 160 mm. Two-dimensional and three-dimensional image reconstructions were performed subsequent to data transfer to a workstation. In one patient suspected of having a vascular dysplasia, high-resolution MSCT imaging was supplemented by multislice computed tomographic angiography. RESULTS Temporal bone dysplasias were encountered in 28 patients (16.7%), affecting the external auditory canal (n = 15), the middle ear (n = 18), the inner ear (n = 5), and the vascular system (n = 3). All temporal bone dysplasias were visualized by two-dimensional and three-dimensional images of excellent detail resolution. In none of the patients were supplementary computed tomographic scans necessary, except for one patient with evidence of an aberrant course of the internal carotid artery. Multislice computed tomographic angiography obviated the need for invasive diagnostic procedures. CONCLUSION: MSCT imaging of the temporal bone allows for comprehensively assessing various dysplasias through high-quality two-dimensional and three-dimensional image reconstructions.