TO THE EDITOR
Letter to the Editor Regarding “Indications for CT-Angiography of the Vertebral Arteries After Trauma”
We would like to commend the authors Drain et al1 for their study assessing the indications for computed tomography angiography (CTA) for diagnosis of blunt vertebral artery injury. However, we have a few questions and concerns about the study.
The stated purpose of the study is to identify risk factors that predict vertebral artery injury, and thereby selecting which patients should undergo screening by CTA. Multiple screening criteria have been published, including the Memphis and Denver criteria for risk stratification for patients who should be screened. The accuracy and utility of those criteria has been disputed. However, it is unclear how the current study resolves the issue, based on only 7.7% patients who underwent screening, at the discretion of the treating physician. And identifying female sex and concurrent blunt carotid injury as high risk would not reduce the number of CTAs. To conclude that CTA may not be indicated without cervical fracture would be erroneous, since imaging is performed not just to exclude vertebral, but also carotid injury.
There is also a significant debate about the sensitivity and specificity of CTA, and the use of digital subtraction angiography in blunt trauma patients.2 The fact that the authors report Grade IV (Occlusion) in 5/9 patients and Grade I/II in only 2/9 patients raises serious questions, since most published literature reports Grade I/II injuries to be much more common. It is also odd that Grade III/IV injuries in this study were treated with aspirin and Coumadin in the acute setting.
Cervical spine fractures as a predictor of vertebral artery injury has been shown by multiple studies, with some fractures being at particularly high-risk, including C1–3 fractures, subluxations, and fractures traversing the transverse foramen.3
It is unclear why the authors included gunshots and stabbing injuries in a study on blunt trauma. Also, the authors state that patients who did not undergo screening were followed for 2 years. We would request the authors to mention what the stroke rate was in this population subset, as well as in patients who were screened and put on treatment.
Having accurate risk factors predicting blunt cerebrovascular injury would help in determining the most cost-effective strategy.4,5 In a recent study, we found the use of CTA to have also significantly increased over the last few years. Awareness of BCVI, risk factors and grading of BCVI would also help improve detection and early treatment.6 Recent literature is showing that anti-thrombotic treatment might be safe in patients with traumatic brain injury and solid organ injury.7 Accurate detection of BCVI becomes even more critical in this context.