University of California Davis School of Medicine, Sacramento, CA.
Division of Interventional Radiology, Department of Radiology, University of California Davis School of Medicine, Sacramento, CA.
J Vasc Surg Venous Lymphat Disord. 2024 May;12(3):101858. doi: 10.1016/j.jvsv.2024.101858. Epub 2024 Mar 5.
In the setting of a known thrombotic event, computed tomography (CT) studies provide reasonable sensitivity for the diagnosis of deep venous thrombosis (DVT). However, the incidence and accuracy of a DVT diagnosis on CT studies not targeted for the detection of DVT are not well described. In addition, the clinical impact of DVTs incidentally identified on CT is unknown.
In this single-institution retrospective study, we queried all contrasted CT studies of the lower extremities performed over a 10-year period. Regular expressions applied to the radiology reports associated with the CT studies identified studies with positive findings associated with DVT. These selected reports were then manually reviewed to confirm the presence of a DVT. Patient demographics and relevant medical and surgical history were obtained through a chart review. Follow-up information was obtained for 1 year after the incident CT and included treatment course, additional imaging, and adverse events. An incidental DVT was one identified in a patient in whom the DVT was not noted in a prior study and for whom the study indication did not include concern for DVT or pulmonary embolism.
Of 16,637 lower extremity contrasted CT studies queried, 37 study reports identified a DVT. However, only 13 patients had a finding of an incidental DVT (10-year incidence of 0.08%). Among these 13 patients, 11 underwent additional imaging, including 9 who had a subsequent venous duplex and 2 who had subsequent CT studies. Among those with a subsequent duplex, DVT was not identified in eight cases, whereas in one case, DVT was confirmed. Among those with subsequent CT studies, DVT was not identified in one case and was confirmed in one case. Of the 13 patients with incidental DVTs, 3 were initiated on anticoagulation based on their initial CT findings alone. Among these, two did not experience any complications from their DVT or anticoagulation regimen. One did experience major bleeding complications, requiring additional procedures.
Incidental DVTs are a rare finding in lower extremity CT studies, noted to occur in only 0.08% of studies. Most patients with incidental DVTs receive additional imaging, with negative findings in 80% of cases. This study identified that 23% of patients were initiated on anticoagulation due to the CT findings, with a 33% rate of significant complications. Currently, a CT venogram is not recommended as a first-line modality for the diagnosis of DVT. However, there is no guidance regarding the need for repeat imaging in patients with incidentally diagnosed lower extremity DVTs identified on CT. Additional study is needed to provide evidence for guideline development.
在已知血栓事件的情况下，计算机断层扫描（CT）检查对深静脉血栓（DVT）的诊断具有合理的敏感性。然而，对于并非专门用于检测 DVT 的 CT 检查中 DVT 诊断的发生率和准确性尚未得到充分描述。此外，偶然在 CT 上发现 DVT 的临床影响尚不清楚。
在这项单机构回顾性研究中，我们对 10 年内进行的所有下肢对比 CT 检查进行了查询。与 CT 检查相关的放射学报告中应用正则表达式来识别与 DVT 相关的阳性发现。然后对这些选定的报告进行手动审查以确认 DVT 的存在。通过病历回顾获取患者的人口统计学和相关医疗及手术史。在发生 CT 后的 1 年内获得随访信息，包括治疗过程、其他影像学检查和不良事件。偶然性 DVT 是指在患者中发现的未在先前研究中发现的 DVT，且该研究的指征不包括对 DVT 或肺栓塞的关注。
在 16637 例下肢对比 CT 检查中，有 37 例报告发现 DVT。然而，只有 13 名患者有偶然性 DVT 的发现（10 年发生率为 0.08%）。在这 13 名患者中，有 11 名进行了额外的影像学检查，其中 9 名进行了后续静脉双功超声检查，2 名进行了后续 CT 检查。在随后进行静脉双功超声检查的 8 例中，没有发现 DVT，而在 1 例中，证实了 DVT 的存在。在随后进行 CT 检查的 2 例中，1 例未发现 DVT，1 例得到证实。在 13 名偶然性 DVT 患者中，有 3 名根据初始 CT 结果开始抗凝治疗。其中，2 名患者未因 DVT 或抗凝方案而出现任何并发症。1 名患者出现严重出血并发症，需要进行额外的治疗。
偶然性 DVT 是下肢 CT 检查中的罕见发现，仅在 0.08%的检查中发现。大多数偶然性 DVT 患者接受了额外的影像学检查，80%的检查结果为阴性。本研究发现，由于 CT 结果，有 23%的患者开始接受抗凝治疗，并发症发生率为 33%。目前，不建议将 CT 静脉造影作为 DVT 诊断的一线方法。然而，对于在 CT 上偶然发现的下肢 DVT 患者，目前尚没有关于重复影像学检查的指南。需要进一步的研究来为指南的制定提供证据。
