Objective. This study aims to assess the impact of adaptive statistical iterative reconstruction (ASIR) on CT imaging quality, diagnostic interpretability, and radiation dose reduction for a proven CT acquisition protocol for total body trauma. Methods. 18 patients with multiple trauma ( ) were examined either with a routine protocol ( ), 30% ( ), or 40% ( ) of iterative reconstruction (IR) modification in the raw data domain of the routine protocol (140？kV, collimation: 40, noise index: 15). Study groups were matched by scan range and maximal abdominal diameter. Image noise was quantitatively measured. Image contrast, image noise, and overall interpretability were evaluated by two experienced and blinded readers. The amount of radiation dose reductions was evaluated. Results. No statistically significant differences between routine and IR protocols regarding image noise, contrast, and interpretability were present. Mean effective dose for the routine protocol was ？mSv, ？mSv for the IR 30, and ？mSv for the IR 40 protocol, that is, 22.1% effective dose reduction for IR 30 ( ) and 30.8% effective dose reduction for IR 40 ( ). Conclusions. IR does not reduce study interpretability in total body trauma protocols while providing a significant reduction in effective radiation dose. 1. Introduction The use of computed tomography (CT) brought enormous benefits to modern medicine and diagnostic CT examinations are increasingly used in recent years because of their speed, availability, and diagnostical power. In particular, for patients with polytrauma during the early resuscitation phase, whole-body CT is recommended as the standard diagnostic modality . However, the common utilization of CT is accompanied by a steady increase in the population’s cumulative exposure to ionizing radiation [2, 3]. As X-rays have been classified as “carcinogen,” new efforts to minimize radiation exposure were undertaken to meet rising concerns of possible long-term cancer, especially regarding pediatric and young patients as well as patients undergoing several follow-up CT examinations . A plurality of approaches, from “AEC” (automated exposure control) to “X-ray beam collimation,” led to a significant reduction in radiation dose [5, 6]. With the fast advancement of computational power, the technique of iterative reconstruction (IR), well known from SPECT and PET imaging, became the center of attention for CT adaption in recent years [7–10]. The group of severely injured patients is of great concern for dose reduction as these patients may be of a young age and standard
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