Department of Radiology, Stanford University School of Medicine, Stanford, CA.
Division of Emergency Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA; Department of Radiology, Newton-Wellesley Hospital, Newton, MA.
Curr Probl Diagn Radiol. 2020 Jul-Aug;49(4):254-259. doi: 10.1067/j.cpradiol.2019.05.002. Epub 2019 May 9.
The US Preventive Services Task Force (USPSTF) recommends 1-time sonographic screening for abdominal aortic aneurysms (AAAs) in male smokers ages 65-75 and other selected individuals in this age group based on risk factors. Patients in this age range are frequent utilizers of lumbar spine MRI, in which the abdominal aorta is typically fully imaged. The purpose of this study was to assess the potential detection rate of AAAs on lumbar spine MRI performed in the USPSTF screening age range with systematic aortic measurement and the frequency with which AAAs are currently reported in practice.
All consecutive lumbar spine MRI exams performed without contrast at a single academic tertiary care center over a 1-year period (4/1/2016-3/31/2017) in patients ages 65-75 were retrospectively reviewed. Maximal anteroposterior, and transverse dimensions of the abdominal aorta were measured using axial T2-weighted images, supplemented with sagittal T2-weighted images if assessment was limited by field-of-view or artifact. The detection rate of AAA, defined as dilation of the aorta to a diameter of ≥3 cm, size of AAAs detected, and frequency with which AAAs were reported, were assessed. Differences in aortic diameters and aneurysm detection rates between genders were compared with the unpaired 2-sample t test.
Three hundred and ninety-five lumbar spine MRIs were reviewed, 240 (60.8%) in women and 155 (39.2%) in men, with mean ± standard deviation (SD) age of 70.2 ± 3.2 years. AAAs were detected in 38/395 (9.6%) cases, most (33/38, 86.8%) of which were <4 cm. Of these, only 4 (10.5%) were reported by the interpreting radiologist; 3/4 (75%) corresponded to aneurysms ≥4 cm.
Lumbar spine MRI performed in the USPSTF AAA screening age range, especially in men, facilitates frequent detection of AAA when the aorta is systematically measured. However, in typical lumbar spine assessment, AAAs are often underreported, particularly for smaller aneurysms.
美国预防服务工作组（USPSTF）建议对年龄在 65-75 岁的男性吸烟者和该年龄段的其他选定人群进行一次性超声筛查，以筛查腹主动脉瘤（AAA）。该年龄段的患者经常接受腰椎 MRI 检查，通常会对整个腹主动脉进行成像。本研究的目的是评估在 USPSTF 筛查年龄范围内进行的腰椎 MRI 检查中，系统测量主动脉时检测到 AAA 的潜在检出率，以及当前在实践中报告 AAA 的频率。
回顾性分析了在一家学术性三级保健中心在 1 年内（2016 年 4 月 1 日至 2017 年 3 月 31 日）进行的无对比剂的连续腰椎 MRI 检查，患者年龄在 65-75 岁之间。使用轴向 T2 加权图像测量腹主动脉的最大前后径和横径，如果评估受到视野或伪影的限制，则使用矢状 T2 加权图像进行补充。评估了 AAA 的检出率，定义为主动脉扩张至≥3cm，检测到的 AAA 大小以及报告 AAA 的频率。使用未配对的 2 样本 t 检验比较了男女之间的主动脉直径和动脉瘤检出率差异。
共回顾了 395 例腰椎 MRI，其中 240 例（60.8%）为女性，155 例（39.2%）为男性，平均年龄±标准偏差（SD）为 70.2±3.2 岁。395 例中发现 38 例（9.6%）AAA，其中大多数（33/38，86.8%）<4cm。其中，只有 4 例（10.5%）由解释放射科医师报告；4 例（75%）符合≥4cm 的动脉瘤。
在 USPSTF AAA 筛查年龄范围内进行的腰椎 MRI 检查，尤其是男性，在系统测量主动脉时，可频繁发现 AAA。但是，在典型的腰椎评估中，AAA 经常报告不足，尤其是对于较小的动脉瘤。
