Radiology Service, VA Palo Alto Health Care System, Palo Alto, CA, USA; Department of Radiology, Stanford University, Stanford, CA, USA.
Curr Probl Diagn Radiol. 2024 May-Jun;53(3):372-376. doi: 10.1067/j.cpradiol.2024.01.022. Epub 2024 Jan 17.
Early detection of abdominal aortic aneurysms (AAAs) is critical given the high morbidity and mortality of a ruptured aneurysm. Screening ultrasound is recommended for men 65 and 75 years of age with a smoking history. However, studies have shown that the rate of ultrasound screening is low and that implicit AAA screening by abdominal imaging studies that were not originally intended for AAA screening can play a major role in AAA detection.
The main objective was to evaluate the role of lumbar spine MRIs as an implicit AAA screening study by assessing the detection rate of AAAs in a broader cohort of veterans that included screening and non-screening populations.
4085 consecutive lumbar spine MRIs from our institution between 2/2020 and 9/2023 were retrospectively reviewed. Each study was labeled AAA present, AAA not present, or indeterminate by radiologists. The correlation between the presence of AAAs and cardiovascular risk factors was assessed using multinomial logistic regression.
AAAs were present in 89 studies (2.2 %) from 80 patients (mean age 75.8 (56-93), M:F 10:0) and absent in 3935 cases (96.3 %) from 3310 patients (mean age 61.7 (19-100), M:F 9:1). Indeterminate cases (n = 61, 1.5 %) were mainly due to incomplete visualization (70.5 %). Mean AAA size was 3.6 cm with most AAAs (n = 43) smaller than 3.5 cm. Sixteen AAAs were 3.5-3.9 cm, 16 between 4 and 4.9cm, and 6 between 5 and 5.9 cm. Artifact precluded measurements in 8 cases. Among the AAA-positive cases, 20 had no prior documentation of AAA. Twenty-one patients with AAAs would not have met the criteria for the routine AAA screening ultrasound. Higher rates of hypertension, hyperlipidemia, and smoking were observed for the AAA cohort at 78.8 % (OR 2.037, CI 1.160-3.576, P = .013), 82.5 % (2.808, 1.543-5.110, P < .001), and 75 % (3.340, 1.979-5.638, P < .001), respectively, compared to the matched no-AAA cohort (58.2 %, 57.6 %, and 50.8 %; n = 2055).
Lumbar spine MRI is a valid modality for implicit screening of AAAs.
Those interpreting lumbar spine MRIs should be vigilant about assessing for AAAs, especially in men with a history of hypertension, hyperlipidemia, or tobacco smoking.
鉴于腹主动脉瘤破裂的高发病率和死亡率，早期发现腹主动脉瘤至关重要。对于有吸烟史的 65 岁和 75 岁男性，建议进行超声筛查。然而，研究表明，超声筛查率较低，原本并非用于腹主动脉瘤筛查的腹部影像学检查的隐性腹主动脉瘤筛查可以在腹主动脉瘤检测中发挥重要作用。
主要目的是通过评估包括筛查和非筛查人群在内的更广泛的退伍军人队列中隐性腹主动脉瘤筛查研究的检测率，评估腰椎 MRI 作为隐性腹主动脉瘤筛查研究的作用。
回顾性分析了 2020 年 2 月至 2023 年 9 月我院连续进行的 4085 例腰椎 MRI 检查。放射科医生将每个研究标记为存在腹主动脉瘤、不存在腹主动脉瘤或不确定。使用多项逻辑回归评估腹主动脉瘤的存在与心血管危险因素之间的相关性。
80 例患者（平均年龄 75.8（56-93）岁，男：女为 10:0）的 89 例（2.2%）研究中存在腹主动脉瘤，3310 例患者（平均年龄 61.7（19-100）岁，男：女为 9:1）的 3935 例（96.3%）研究中不存在腹主动脉瘤。（n=61，1.5%）不确定病例主要是由于不完全可视化（70.5%）。平均腹主动脉瘤大小为 3.6cm，大多数腹主动脉瘤（n=43）小于 3.5cm。16 个腹主动脉瘤为 3.5-3.9cm，16 个为 4-4.9cm，6 个为 5-5.9cm。8 例因伪影而无法进行测量。在腹主动脉瘤阳性病例中，有 20 例无腹主动脉瘤的既往记录。21 例有腹主动脉瘤的患者不符合常规腹主动脉瘤超声筛查标准。与匹配的无腹主动脉瘤队列（58.2%、57.6%和 50.8%；n=2055）相比，腹主动脉瘤组的高血压、高血脂和吸烟率分别为 78.8%（OR 2.037，CI 1.160-3.576，P=0.013）、82.5%（2.808，CI 1.543-5.110，P<0.001）和 75%（3.340，CI 1.979-5.638，P<0.001）。
腰椎 MRI 是一种用于隐性腹主动脉瘤筛查的有效方法。
解读腰椎 MRI 的人员应警惕腹主动脉瘤的存在，尤其是在有高血压、高血脂或吸烟史的男性中。
