Department of Radiology, G.B. Rossi Hospital, University of Verona, Piazzale Scuro 10, 37134 Verona, Italy.
Eur J Radiol. 2012 Aug;81(8):1742-50. doi: 10.1016/j.ejrad.2011.04.066. Epub 2011 May 23.
To evaluate the accuracy in distinguishing adrenal adenomas from nonadenomas by means of quadriphasic CT exam, including unenhanced (UE), arterial enhanced (AE), portal enhanced (PE) and 5-min delayed enhanced (DE) CT scans.
This retrospective study had institutional review board approval; the need for informed consent was waived. From September 2007 to September 2009, 104 adrenal masses were evaluated in 87 patients (49 M, 38 F, mean age 58.4 years) undergoing UE, AE (35-s delay), PE (80-s delay) and DE (5-min delay) CT scans. The mean adrenal attenuation during all imaging phases was measured by two readers. The accuracy values of absolute unenhanced attenuation (UE), absolute wash-out (AWO), relative percentage wash-out (RPWO) and percentage enhancement wash-out (PEW) were assessed by using receiver operator curves (ROC) analysis. The overall accuracy of the quadriphasic protocol and other triphasic protocols were evaluated. A value of p≤0.05 was considered significant.
The accuracy in characterizing adrenal lesions was 86.5% (90/104) for UE attenuation (≤10 HU threshold), 90.1% (82/91) for RPWO (≥30% threshold), 85.7% (78/91) for AWO (≥12 HU threshold) and 83.5% (76/91) for PEW (≥30% threshold), respectively. Quadriphasic CT (accuracy 97.1%, 101/104) performed better than triphasic CT including only AE scan (efficiency 90.0%, 94/104; p=0.011) and triphasic CT including only PE scan (efficiency 96.1%, 100/104; p=0.025).
Quadriphasic CT protocol including 5-min DE scan may be used to characterize incidentally detected adrenal masses. RPWO represented the best wash-out parameter for characterizing adrenal lesions.
通过包括平扫（UE）、动脉期增强（AE）、门脉期增强（PE）和 5 分钟延迟增强（DE）CT 扫描在内的四期 CT 检查，评估区分肾上腺腺瘤和非腺瘤的准确性。
本回顾性研究获得了机构审查委员会的批准；无需获得知情同意。2007 年 9 月至 2009 年 9 月，对 87 例患者（49 例男性，38 例女性，平均年龄 58.4 岁）的 104 个肾上腺肿块进行了评估，这些患者接受了 UE、AE（35 秒延迟）、PE（80 秒延迟）和 DE（5 分钟延迟）CT 扫描。两位读者分别测量了所有成像阶段的平均肾上腺衰减值。使用受试者工作特征曲线（ROC）分析评估绝对平扫衰减（UE）、绝对洗脱（AWO）、相对百分比洗脱（RPWO）和百分比增强洗脱（PEW）的准确度值。评估了四期方案和其他三期方案的整体准确性。p≤0.05 被认为具有统计学意义。
UE 衰减（≤10 HU 阈值）、RPWO（≥30%阈值）、AWO（≥12 HU 阈值）和 PEW（≥30%阈值）分别对肾上腺病变特征的准确率为 86.5%（90/104）、90.1%（82/91）、85.7%（78/91）和 83.5%（76/91）。四期 CT（准确率 97.1%，101/104）的效果优于仅包括 AE 扫描的三期 CT（效率 90.0%，94/104；p=0.011）和仅包括 PE 扫描的三期 CT（效率 96.1%，100/104；p=0.025）。
包括 5 分钟 DE 扫描的四期 CT 方案可用于描述偶然发现的肾上腺肿块。RPWO 是描述肾上腺病变的最佳洗脱参数。
