Ultralow Dose Dynamic Expiratory Computed Tomography for Evaluation of Tracheomalacia

Objective The aim of this study was to determine the average effective radiation dose and feasibility of ultralow dose dynamic expiratory computed tomography (CT) for evaluation of tracheomalacia (ULD) and to evaluate factors that impact image quality. Methods This is a retrospective study of 64 consecutive patients from September to October 2016 for the evaluation of tracheomalacia. All studies were performed with routine inspiration chest CT followed by ULD z(kilovoltage peak (kVp) 80, 100, or 120 and fixed milliamperage 10) or typical dose CT (TD) (kVp 100 or 120 with automated milliamperage) dynamic expiration CT. Image quality was considered diagnostic if the trachea area could be accurately measured for tracheomalacia assessment, and diagnostic studies were graded fair, good, or excellent. Scan length, image quality, and effective radiation dose were compared for ULD versus TD and ULD at 100 kVp versus ULD at 80 kVp. For ULD studies, patient factors were compared across image quality. Results The ULD had a mean effective radiation dose of 0.08 mSv, with all studies of diagnostic image quality. The ULD showed 95% reduction in effective radiation dose (P
Source: Journal of Computer Assisted Tomography - Category: Radiology Tags: Cardiovascular and Thoracic Imaging Source Type: research