a Department of Radiology , Loghman-Hakim Hospital, Shahid Beheshti University of Medical Sciences , Tehran , Iran.
b Department of Clinical Toxicology , Loghman-Hakim Hospital, Shahid Beheshti University of Medical Sciences , Tehran , Iran.
Clin Toxicol (Phila). 2018 May;56(5):348-354. doi: 10.1080/15563650.2017.1377220. Epub 2017 Sep 14.
Detection of body stuffers is challenging in emergency departments. Because of the small size of baggies, plain radiograph is of little value in most suspects. On the other hand, abdomen CT scan is burdened by high cost and radiation dose. This study was performed to compare the image quality, radiation dose and accuracy of low-dose CT scan in comparison with standard dose.
In this prospective study, suspected body stuffers who were referred to the radiology department underwent two different protocols of abdominal non-contrast CT scan simultaneously: low-dose (with equivalent dose to conventional abdominal x-ray) and standard dose. Standard dose CT scan was considered as the reference. Low-dose CT scans were evaluated for detection of baggies by two radiologists blinded to the result of standard dose CT. Image quality, noise, dose-length product (DLP) and effective dose (ED) compared between two groups.
The study consisted of 40 patients (33.38 ± 7.4 years). Standard dose CT evaluation was positive in 22 patients (55%). In comparison with standard dose CT scan, low-dose group had a sensitivity of 86%, specificity of 100%, PPV and NPV of 100% and 86%. The accuracy of low-dose CT scan for detection of baggies larger than 1 cm was 100%. However, from the 3 cases that could not be detected with low dose protocol, one had CT features suspected for baggies rupture which was intubated and later deceased. Noise average of low-dose protocol, was approximately 7 times greater than standard dose group, while DLP and ED were 9.7 times less.
Low dose CT scan appears to be an appropriate screening method for body stuffers, especially when the baggies are larger than one centimeter. However, in the presence of severe clinical symptoms, a standard dose CT scan will be more helpful due to better image quality especially in suspected ruptured baggies.
在急诊科，检测体内藏物是具有挑战性的。由于袋子的体积小，普通 X 光片对大多数疑似病例几乎没有价值。另一方面，腹部 CT 扫描的费用高且辐射剂量大。本研究旨在比较低剂量 CT 扫描与标准剂量扫描的图像质量、辐射剂量和准确性。
在这项前瞻性研究中，疑似体内藏物的患者同时接受两种不同方案的腹部非对比 CT 扫描：低剂量（与常规腹部 X 射线等效剂量）和标准剂量。标准剂量 CT 扫描被视为参考。两位对标准剂量 CT 扫描结果不知情的放射科医生对低剂量 CT 扫描进行评估，以检测袋子的存在。比较两组之间的图像质量、噪声、剂量长度乘积（DLP）和有效剂量（ED）。
该研究共纳入 40 名患者（33.38±7.4 岁）。标准剂量 CT 评估阳性 22 例（55%）。与标准剂量 CT 扫描相比，低剂量组的敏感度为 86%，特异度为 100%，PPV 和 NPV 均为 100%，敏感度为 86%。低剂量 CT 扫描检测大于 1cm 的袋子的准确率为 100%。然而，在无法通过低剂量方案检测到的 3 例中，有 1 例 CT 特征疑似袋子破裂，该患者进行了插管，后来死亡。低剂量方案的平均噪声约为标准剂量组的 7 倍，而 DLP 和 ED 则分别减少了 9.7 倍。
低剂量 CT 扫描似乎是一种检测体内藏物的合适筛查方法，尤其是当袋子大于 1 厘米时。然而，在存在严重临床症状的情况下，由于更好的图像质量，特别是在疑似破裂的袋子的情况下，标准剂量 CT 扫描将更有帮助。
