Sixteen-slice CT angiography in patients with suspected blunt carotid and vertebral artery injuries

Abstract

Conclusion:The arterial phase of computed tomography (CT) imaging is not necessary for routine detection of endoleaks. This portion of CT evaluation after endovascular AAA repair can be eliminated, with a reduction in radiation exposure.Summary: This was a retrospective analysis performed of arterial and venous phases of CT scans evaluating for endoleak in patients with endovascular repair of an abdominal aortic aneurysm (AAA). The purpose was to determine if the arterial phase of CT scanning for evaluation of endoleak can be potentially eliminated, thus lowering radiation exposure. The authors analyzed 85 patients (66 men and 19 women; mean age, 66 years) who underwent endovascular repair of an AAA. There were 110 multidetector CT examinations available for analysis. The CT protocol for endoleak evaluation included first obtaining a noncontrast, enhanced set of CT images. After this, intravenous contrast material was administered, and both arterial and venous phase images were obtained.Nonenhanced and venous phase images were evaluated to determine if an endoleak was present. Arterial phase images were analyzed separately. It was then determined how often the arterial phase imaging contributed to the diagnosis of endoleak.A total of 28 type II endoleaks were detected with a combination of nonenhanced and venous phase CT acquisitions. Of these 28 endoleaks, 25 endoleaks were also visualized during the arterial phase of the CT scan, with three type II endoleaks only seen during the venous phase. No additional endoleaks were seen with the arterial phase. Seventy-eight scans from 67 patients revealed no endoleak during the venous phase; and in these scans, no endoleaks were discovered with the arterial phase images. The arterial phase of the CT scan was responsible for 36.5% of the radiation exposure during the combination of noncontrast, venous, and arterial phase images.Comment: The radiation administered during a diagnostic CT scan is associated with low, but not zero, health risk. This radiation has been linked to an increase in life-long risk of cancer (Radiology 2004;232:735-8). Because type II endoleaks are relatively benign, the increased radiation dose of arterial phase acquisitions does not seem warranted. Additional data are required to know whether the arterial phase acquisitions may, however, remain necessary to detect small type I or type III endoleaks.

Whole-Body CT Trauma Imaging with Adapted and Optimized CT Angiography of the Craniocervical Vessels: Do We Need an Extra Screening Examination?

“…Third, the BCVI cohort consists of only 6 patients, which is a small number, but then the entity under investigation is uncommon; this limitation is also shared by other studies. 17,19,33 In comparison with the clinical risk factors, which were used by other authors 9,10,14,15 to identify patients who should undergo screening examinations, sensitivity and specificity for CTA were 100% with a PPV of 1 and a NPV of 0. Because the incidence of BCVI and of patients with multiple injured vessels is in the range reported by other authors, we believe that our data may reflect the true accuracy of 16-row MSCT angiography in screening a general blunt trauma population for BCVI.…”

“…[5][6][7][8] In the light of the potential devastating consequences of BCVI, much effort has focused on improving detection and treatment during the past decade. 9,10 Initially, neurologic deficits were thought to be inevitable in these patients, but prompt systemic anticoagulation before the onset of stroke has significantly reduced ischemic neurologic events in such patients. 8,11 On the basis of these insights and increased awareness of BCVI, subsequent efforts have been directed toward the identification of injuries before the onset of stroke, resulting in screening protocols 7,12,13 according to mechanism of injury and specific injury patterns 9,10,14,15 (Table 1).…”

“…5,10,14 However, with advanced CTA technology, there is increasing enthusiasm about CTA and its potential to become the main diagnostic technique to detect BCVI. 9,[17][18][19][20] The advantage of CTA is that it can be easily integrated into existing protocols for CT work-up of patients with multiple trauma who already undergo CT for other reasons. However, in most studies, patients with trauma often undergo both body trauma imaging and CTA but as separate studies.…”

Blunt Cerebrovascular Injuries: Diagnosis and Management Outcomes

“…In recent years, many centres have adopted multi-detector computed tomographic angiography (CTA) to diagnose BCVI non-invasively in the setting of trauma. Studies have shown that CTA of the neck can serve as a reliable screening modality for BCVI in patients at risk for vascular injuries 1,3,5,19 .…”

Blunt cerebrovascular injuries in acute trauma care: a screening protocol

“…In the meantime, several studies have validated the use of the CTA as a sensitive tool in the diagnostics of BCVIs particularly concerning technical innovation and further development about the resolution of the CT [2,4,10,30]. However, the limitation for the use of a CTA in BCVI diagnostic is the availability of a 16-slice CT system [2,4,10,30]. The efficiency of trauma CT scan of a severely injured patient can be increased by the CTA of the intraand extracerebral vessels without an essential loss of time.…”