Department of Head Quarter Diagnostic Imaging, Dubai Health Authority, Dubai, United Arab Emirates
College of Medicine, Mohammed Bin Rashid University, Dubai, United Arab Emirates
Curr Med Imaging. 2024;20:e220523217204. doi: 10.2174/1573405620666230522151357.
The majority of the existing diagnostic reference levels (DRLs) that have been established for computed tomography (CT) are based on various anatomical locations, such as the head, chest, abdomen, etc. However, DRLs are initiated to improve radiation protection by conducting a comparison of similar examinations with similar objectives. The aim of this study was to explore the feasibility of establishing dose baselines based on common CT protocols for patients who underwent enhanced CT abdomen and pelvis exams.
Dose length product total (tDLPs), volumetric CT dose index (CTDIvol), size-specific dose estimate (SSDE), effective dose (E), and scan acquisition parameters for a total of 216 adult patients, who underwent an enhanced CT abdomen and pelvis exams over a one-year period, were obtained and retrospectively analyzed. Spearman coefficient and one-way ANOVA tests were used to check significant differences between dose metrics and the different CT protocols.
The data exhibited 9 different CT protocols to acquire an enhanced CT abdomen and pelvis exam at our institute. Out of these, 4 were found more common, i.e., CT protocols were acquired for a minimum of 10 cases. Triphasic liver demonstrated the highest mean and median tDLPs across all 4 CT protocols. Triphasic liver protocol registered the highest E followed by gastric sleeve protocol with a mean of 28.7 and 24.7 mSv, respectively. Significant differences (p < 0.0001) were found between the tDLPs of anatomical location and the CT protocol.
Evidently, wide variability exists across CT dose indices and patient dose metrics relying on anatomical-based dose baseline, i.e., DRLs. Patient dose optimizations require establishing dose baselines based on CT protocols rather than the anatomical location.
大多数已建立的计算机断层扫描（CT）诊断参考水平（DRL）是基于各种解剖部位的，如头部、胸部、腹部等。然而，DRL 的建立是为了通过比较具有相似目标的类似检查来改善辐射防护。本研究旨在探讨基于腹部和盆腔增强 CT 检查常见 CT 方案为患者建立剂量基线的可行性。
回顾性分析了 216 例成年患者在一年内进行腹部和盆腔增强 CT 检查的剂量长度乘积总（tDLPs）、容积 CT 剂量指数（CTDIvol）、体积剂量指标（SSDE）、有效剂量（E）和扫描采集参数。使用 Spearman 系数和单向方差分析检验剂量指标与不同 CT 方案之间的差异。
数据显示，我院有 9 种不同的 CT 方案用于获取腹部和盆腔增强 CT 检查。其中 4 种方案更为常见，即至少有 10 例患者采用了这些方案。在所有 4 种 CT 方案中，肝三期检查的平均和中位数 tDLPs 最高。肝三期检查的 E 值最高，其次是胃袖状切除术方案，平均分别为 28.7 和 24.7 mSv。不同 CT 方案与解剖部位之间的 tDLPs 差异有统计学意义（p<0.0001）。
显然，基于解剖学的剂量基线（即 DRL）的 CT 剂量指标和患者剂量指标存在很大差异。患者剂量优化需要基于 CT 方案而不是解剖部位建立剂量基线。
