Department of Diagnostic Radiology, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-Ku, Tokyo 113-8510, Japan.
Department of Radiology, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-Ku, Tokyo 113-8510, Japan.
Tomography. 2022 Apr 8;8(2):1079-1089. doi: 10.3390/tomography8020088.
Routine CT examinations are crucial in colorectal cancer patients (CCPs); however, the high frequency of radiation exposure is a significant concern. This study investigated the radiation dose, image quality, and diagnostic performance of tin filter-based spectral shaping chest−abdominal−pelvic (CAP) CT for CCPs. We reviewed 44 CCPs who underwent single-phase enhanced tin-filtered 100 kV (TF100kV) and standard 120 kV (ST120kV) CAP CT on separate days. Radiation metrics including the volume CT dose index (CTDIvol), dose-length product (DLP), and effective dose (ED) were calculated for both protocols. Two radiologists assessed the presence of the following lesions: lung metastasis, liver metastasis, lymph node metastasis, peritoneal dissemination, and bone metastasis. The area under the receiver operating characteristic curve (AUC) was calculated for the diagnostic performance of each protocol. Radiation metrics of the TF100kV protocol were significantly lower than those of the ST120kV protocol (CDTIvol 1.60 ± 0.31 mGy vs. 14.4 ± 2.50, p < 0.0001; DLP 107.1 (95.9−125.5) mGy·cm vs. 996.7 (886.2−1144.3), p < 0.0001; ED 1.93 (1.73−2.26) mSv vs. 17.9 (16.0−20.6), p < 0.0001, respectively). TF100kV protocol achieved comparable diagnostic performance to that of the ST120kV protocol (AUC for lung metastasis: 1.00 vs. 0.94; liver metastasis: 0.88 vs. 0.83, respectively). TF100kV protocol could substantially reduce the radiation dose by 89% compared to that with the ST120kV protocol while maintaining good diagnostic performance in CCPs.
常规 CT 检查对结直肠癌患者（CCP）至关重要；然而，高辐射暴露频率是一个重大问题。本研究调查了基于锡滤器的光谱成形胸部-腹部-骨盆（CAP）CT 对 CCP 的辐射剂量、图像质量和诊断性能。我们回顾了 44 例 CCP，他们分别在两天内接受了单相增强锡滤器 100 kV（TF100kV）和标准 120 kV（ST120kV）CAP CT。为两种方案计算了包括容积 CT 剂量指数（CTDIvol）、剂量长度乘积（DLP）和有效剂量（ED）在内的辐射指标。两位放射科医生评估了以下病变的存在情况：肺转移、肝转移、淋巴结转移、腹膜扩散和骨转移。计算了每种方案的诊断性能的受试者工作特征曲线（AUC）下面积。TF100kV 方案的辐射指标明显低于 ST120kV 方案（CDTIvol 1.60±0.31 mGy 比 14.4±2.50，p<0.0001；DLP 107.1（95.9-125.5）mGy·cm 比 996.7（886.2-1144.3），p<0.0001；ED 1.93（1.73-2.26）mSv 比 17.9（16.0-20.6），p<0.0001）。TF100kV 方案与 ST120kV 方案的诊断性能相当（肺转移的 AUC：1.00 比 0.94；肝转移：0.88 比 0.83）。与 ST120kV 方案相比，TF100kV 方案可将辐射剂量降低 89%，同时保持 CCP 良好的诊断性能。
