Sabarudin Akmal, Mustafa Zakira, Nassir Khadijah Mohd, Hamid Hamzaini Abdul, Sun Zhonghua
Diagnostic Imaging & Radiotherapy Program School of Diagnostic & Applied Health Sciences Faculty of Health Sciences Universiti Kebangsaan Malaysia 50300 Kuala Lumpur, Malaysia..
J Appl Clin Med Phys. 2014 Jan 8;16(1):5135. doi: 10.1120/jacmp.v16i1.5135.
This phantom study was designed to compare the radiation dose in thoracic and abdomen-pelvic CT scans with and without use of tube current modulation (TCM). Effective dose (ED) and size-specific dose estimation (SSDE) were calculated with the absorbed doses measured at selective radiosensitive organs using a thermoluminescence dosimeter-100 (TLD-100). When compared to protocols without TCM, the ED and SSDE were reduced significantly with use of TCM for both the thoracic and abdomen-pelvic CT. With use of TCM, the ED was 6.50 ± 0.29 mSv for thoracic and 6.01 ± 0.20 mSv for the abdomen-pelvic CT protocols. However without use of TCM, the ED was 20.07 ± 0.24 mSv and 17.30 ± 0.41 mSv for the thoracic and abdomen-pelvic CT protocols, respectively. The corresponding SSDE was 10.18 ± 0.48 mGy and 11.96 ± 0.27 mGy for the thoracic and abdomen-pelvic CT protocols with TCM, and 31.56 ± 0.43 mGy and 33.23 ± 0.05 mGy for thoracic and abdomen-pelvic CT protocols without TCM, respectively. The highest absorbed dose was measured at the breast with 8.58 ± 0.12 mGy in the TCM protocols and 51.52 ± 14.72 mGy in the protocols without TCM during thoracic CT. In the abdomen-pelvic CT, the absorbed dose was highest at the skin with 9.30 ± 1.28mGy and 29.99 ± 2.23 mGy in protocols with and without use of TCM, respectively. In conclusion, the TCM technique results in significant dose reduction; thus it is to be highly recommended in routine thoracic and abdomen-pelvic CT.
本体模研究旨在比较使用和不使用管电流调制（TCM）的胸部和腹部-盆腔CT扫描的辐射剂量。使用热释光剂量仪-100（TLD-100）在选择性放射敏感器官处测量吸收剂量，计算有效剂量（ED）和特定尺寸剂量估计（SSDE）。与不使用TCM的方案相比，使用TCM进行胸部和腹部-盆腔CT扫描时，ED和SSDE均显著降低。使用TCM时，胸部CT方案的ED为6.50±0.29 mSv，腹部-盆腔CT方案的ED为6.01±0.20 mSv。然而，不使用TCM时，胸部和腹部-盆腔CT方案的ED分别为20.07±0.24 mSv和17.30±0.41 mSv。使用TCM的胸部和腹部-盆腔CT方案对应的SSDE分别为10.18±0.48 mGy和11.96±0.27 mGy，不使用TCM的胸部和腹部-盆腔CT方案对应的SSDE分别为31.56±0.43 mGy和33.23±0.05 mGy。在胸部CT中，使用TCM的方案中乳房处测得的吸收剂量最高，为8.58±0.12 mGy，不使用TCM的方案中为51.52±14.72 mGy。在腹部-盆腔CT中，使用和不使用TCM的方案中皮肤处的吸收剂量最高，分别为9.30±1.28 mGy和29.99±2.23 mGy。总之，TCM技术可显著降低剂量；因此，在常规胸部和腹部-盆腔CT中强烈推荐使用。
