Division of Pediatric Radiology, Department of Radiology, Medical University of Graz, Graz, Austria.
Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
World J Urol. 2020 Nov;38(11):2971-2979. doi: 10.1007/s00345-020-03082-6. Epub 2020 Jan 28.
To assess a novel low-dose CT-protocol, combining a 150 kV spectral filtration unenhanced protocol (Sn150 kVp) and a stone-targeted dual-energy CT (DECT) in patients with urolithiasis.
232 (151 male, 49 ± 16.4 years) patients with urolithiasis received a low-dose non-contrast enhanced CT (NCCT) for suspected urinary stones either on a third-generation dual-source CT system (DSCT) using Sn150 kVp (n = 116, group 1), or on a second-generation DSCT (n = 116 group 2) using single energy (SE) 120 kVp. For group 1, a subsequent dual-energy CT (DECT) with a short stone-targeted scan range was performed. Objective and subjective image qualities were assessed. Radiation metrics were compared.
534 stones (group 1: n = 242 stones; group 2: n = 292 stones) were found. In group 1, all 215 stones within the stone-targeted DECT-scan range were identified. DE analysis was able to distinguish between UA and non-UA calculi in all collected stones. 11 calculi (5.12%) were labeled as uric acid (UA) while 204 (94.88%) were labeled as non-UA calculi. There was no significant difference in overall Signal-to-noise-ratio between group 1 and group 2 (p = 0.819). On subjective analysis both protocols achieved a median Likert rating of 2 (p = 0.171). Mean effective dose was significantly lower for combined Sn150 kVp and stone-targeted DECT (3.34 ± 1.84 mSv) compared to single energy 120 kVp NCCT (4.45 ± 2.89 mSv) (p < 0.001), equaling a 24.9% dose reduction.
The evaluated novel low-dose stone composition protocol allows substantial radiation dose reduction with consistent high diagnostic image quality.
评估一种新的低剂量 CT 方案，该方案结合了 150kV 能谱过滤未增强方案（Sn150kVp）和结石靶向双能 CT（DECT）在尿路结石患者中的应用。
232 例（男 151 例，49±16.4 岁）尿路结石患者因疑似尿路结石接受低剂量非增强 CT（NCCT）检查，分别在第三代双源 CT 系统（DSCT）上使用 Sn150kVp（n=116，第 1 组）或第二代 DSCT（n=116，第 2 组）进行单能 120kVp 检查。第 1 组随后进行结石靶向的短扫描范围双能 CT（DECT）检查。评估客观和主观图像质量。比较辐射指标。
共发现 534 个结石（第 1 组：n=242 个结石；第 2 组：n=292 个结石）。在第 1 组中，所有位于结石靶向 DECT 扫描范围内的 215 个结石均被识别。DE 分析能够在所有采集的结石中区分尿酸盐（UA）和非-UA 结石。11 个结石（5.12%）被标记为尿酸（UA），而 204 个结石（94.88%）被标记为非-UA 结石。第 1 组和第 2 组之间的总信噪比无显著差异（p=0.819）。在主观分析中，两个方案的中位数 Likert 评分均为 2（p=0.171）。与单能 120kVp NCCT（4.45±2.89mSv）相比，联合使用 Sn150kVp 和结石靶向 DECT 的平均有效剂量显著降低（3.34±1.84mSv）（p<0.001），剂量降低 24.9%。
评估的新型低剂量结石成分方案可显著降低辐射剂量，同时保持高诊断图像质量。
