Prospektive, randomisierte Evaluation eines modifizierten Mehrdetektor-CT-Protokolls in der Initialdiagnostik beim Polytrauma

Abstract

To evaluate whether modification of a standard multislice CT (MSCT) protocol might improve the diagnostic work flow in patients with multiple trauma without relevant loss of image quality. Between September 2002 and September 2003, 80 multiple trauma patients underwent 4-slice CT encompassing head, thorax, abdomen/pelvis and spine. All patients were randomly assigned to either protocol A or B: Protocol A included serial scanning of the head (collimation 1 mm, 350/380 mAs/120 kV) and spiral scans of thorax, abdomen/pelvis and spine (collimation 2.5 mm, 220 mAs/120 kV) with gantry angulation and arm elevation; protocol B included spiral scanning of all body regions (collimation 2.5 mm, 300/150 mAs/120 kV) without gantry angulation or arm elevation. Time intervals, radiation exposure and results of the initial and final analysis were documented. In the investigated 64 male and 16 female patients (mean age 41.7 years), 88.7 % of the 407 pathologic findings were correctly identified on the initial images. Protocol B revealed a significant decrease in scan time (6.4 vs. 16.8 min., p < 0.001), time in the CT examination room (22.9 vs. 32.8 min.; p < 0.001), time until initial (25.3 vs. 35.8 min.; p < 0.001) and final image analysis (93.7 vs. 112.9 min; p < 0.005). No significant difference was found for patient transport time and image reconstruction time. Protocol B has a significantly lower effective radiation dose compared to protocol A (10.2 vs. 12.7 mSv, p < 0.001). Applying a modified MSCT protocol without gantry angulation and arm elevation can significantly decrease radiation exposure and examination time in multiple trauma patients without relevant loss of diagnostic image information and, consequently, has the potential of improving the diagnostic process and prognosis in multiple trauma patients.