Bennett Debbie L, Hamberg Leena M, Wang Bing, Hirsch Joshua A, González R Gilberto, Hunter George J
Massachusetts General Hospital, Department of Radiology, Boston, Massachusetts, United States of America.
Brigham and Women's Hospital, Department of Radiology, Boston, Massachusetts, United States of America.
PLoS One. 2014 Jun 6;9(6):e99020. doi: 10.1371/journal.pone.0099020. eCollection 2014.
To evaluate how often delayed images, obtained during neurovascular CTA, provide unique information relative to early phase imaging alone.
Informed consent was waived by the institutional review body for this study. Neurovascular CTAs from January through June 2009 were searched to identify those with delayed phase imaging. Reports were reviewed to identify cases where delayed images provided potentially unique information. The studies with potentially unique information were re-interpreted to determine if the information was indeed unique.
645 CTAs with delayed phase imaging were identified. There were 324 men and 310 women (median age 67 years; range 20-96 years). 59 studies (59/645: 9.1%) had findings on the delayed images. There were 13 cases with hemorrhage, with 4 showing progression on delayed views. Of the remaining 46 cases, 28 had occlusion of a vessel that did not reconstitute on the delayed images, 6 had occlusion of a vessel that did reconstitute on the delayed images, 7 had a string sign which was unchanged on the delayed views and 5 had no abnormal findings. Thus in 10 cases the findings were unique to the delayed images (10/645: 1.55%). Four showed active bleeding, three showed proximal occlusion with distal internal carotid filling from ophthalmic collaterals, two showed pial vessels filling distal to proximal MCA occlusion, and one showed retrograde vertebral artery filling due to subclavian steal. 95% confidence limits of the expected incidence of unique information from the delayed phase images are 0.6%-2.5%.
Obtaining delayed phase imaging for neurovascular CTA should be an active decision and not the default protocol. This avoids imaging with little, if any value. If delayed images had not been obtained in our cohort, no detriment in patient management would have occurred.
评估在神经血管CT血管造影（CTA）过程中获取的延迟期图像相对于仅早期成像能提供独特信息的频率。
本研究经机构审查委员会批准可免除知情同意。检索2009年1月至6月期间的神经血管CTA，以识别有延迟期成像的检查。审查报告以确定延迟期图像提供潜在独特信息的病例。对具有潜在独特信息的研究进行重新解读，以确定该信息是否确实独特。
共识别出645例有延迟期成像的CTA。其中男性324例，女性310例（中位年龄67岁；范围20 - 96岁）。59项研究（59/645：9.1%）在延迟期图像上有发现。有13例出血，其中4例在延迟期图像上显示有进展。在其余46例中，28例血管闭塞在延迟期图像上未再显影，6例血管闭塞在延迟期图像上再显影，7例有串珠征且在延迟期图像上无变化，5例无异常发现。因此，有10例的发现是延迟期图像所独有的（10/645：1.55%）。4例显示活动性出血，3例显示近端闭塞且眼动脉侧支使颈内动脉远端充盈，2例显示大脑中动脉闭塞远端至近端的软脑膜血管充盈，1例显示由于锁骨下动脉盗血导致椎动脉逆行充盈。延迟期图像中独特信息预期发生率的95%置信区间为0.6% - 2.5%。
对于神经血管CTA获取延迟期成像应是一个主动的决策，而非默认方案。这样可避免进行几乎无价值的成像。如果在我们的队列中未获取延迟期图像，对患者管理不会造成损害。
