Aims Contrast-enhanced computed tomography (CE-CT) is the gold standard for diagnosing acute aortic syndromes (AAS). Unenhanced computed tomography (unenhanced-CT) also provides specific findings for AAS; however, its diagnostic ability is not well discussed. This study aims to evaluate the potential of unenhanced-CT as an AAS screening tool. Methods and results We retrospectively examined AAS patients who visited our hospital between 2011 and 2021 to validate the diagnostic value of unenhanced-CT alone and along with the aortic dissection detection risk score (ADD-RS) plus D-dimer. Acute aortic syndrome was assessed as detectable using unenhanced-CT with any of the following findings: pericardial haemorrhage, high-attenuation haematoma, and displacement of intimal calcification or a flap. Of the 316 AAS cases, 292 (92%) were detectable with unenhanced-CT. Twenty-four (8%) cases undetectable with unenhanced-CT involved younger patients [median (interquartile range), 45 (42–51) years vs. 72 (63–80) years, P < 0.001] and patients more frequently complicated with a patent false lumen (79% vs. 42%, P < 0.001). Acute aortic syndrome-detection rate with unenhanced-CT increased with age, reaching 98% (276/282) in those ≥50 years of age and 100% (121/121) in those ≥75 years of age. With the ADD-RS plus D-dimer, there was only one AAS case undetectable with unenhanced-CT among patients ≥50 years of age, except for cases with the ADD-RS ≥1 plus D-dimer levels of ≥0.5 μg/mL. Conclusion Acute aortic syndromes in younger patients and patients with a patent false lumen could be misdiagnosed with unenhanced-CT alone. The combination of the ADD-RS plus D-dimer and unenhanced-CT could minimize AAS misdiagnosis while avoiding over-testing with CE-CT.

中文翻译：

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非增强计算机断层扫描作为急性主动脉综合征筛查工具的潜力

目的 对比增强计算机断层扫描 (CE-CT) 是诊断急性主动脉综合征 (AAS) 的金标准。非增强计算机断层扫描（unenhanced-CT）也为 AAS 提供了特定的发现；然而，它的诊断能力没有得到很好的讨论。本研究旨在评估非增强 CT 作为 AAS 筛查工具的潜力。方法和结果 我们回顾性检查了 2011 年至 2021 年期间访问我院的 AAS 患者，以验证单纯 CT 和主动脉夹层检测风险评分 (ADD-RS) 加 D-二聚体的诊断价值。使用非增强 CT 评估急性主动脉综合征是可检测的，具有以下任何发现：心包出血、高密度血肿和内膜钙化或皮瓣移位。在 316 例 AAS 病例中，平扫 CT 可检测到 292 例 (92%)。24 例 (8%) 例未通过非增强 CT 检测到的病例涉及年轻患者 [中位数（四分位距），45 (42-51) 岁 vs. 72 (63-80) 岁，P <; 0.001] 且患者更常并发假腔未闭（79% 对 42%，P < 0.001）。非增强 CT 的急性主动脉综合征检出率随着年龄的增长而增加，≥50 岁的人群达到 98% (276/282)，≥75 岁的人群达到 100% (121/121)。使用 ADD-RS 加 D-二聚体时，在 50 岁以上的患者中，除了 ADD-RS ≥1 加 D-二聚体水平≥0.5 μg/mL 的病例外，只有 1 例 AAS 病例在未增强 CT 中检测不到. 结论 单纯 CT 平扫可能会误诊年轻患者和假腔未闭患者的急性主动脉综合征。