TO THE EDITOR
Letter to Indications for CT Angiography of the Vertebral Arteries After Trauma
We read with great interest the article by Drain et al.1 The authors conducted their study to identify factors that predict vertebral artery injury (VAI) after trauma. Finally, they concluded that female sex, lower Glasgow Coma Scale, cervical spine fracture, and concurrent blunt carotid injury (BCI) were risk factors for VAI. The clinical importance of the article was undisputed. However, we have some concerns about this study.
First, it has been reported that computed tomography angiography (CTA) can increase detection of blunt vertebral artery injury in patients with blunt trauma.2–4 However, screening with CTA or magnetic resonance angiography for blunt cerebrovascular injury (BCVI) was only performed in 144 (7.77%) patients in the study. And all of the nine VAI were diagnosed in the screening group, and no VAI was diagnosed in the nonscreening group. It was probable that some BCVI were neglected in the 1710 (92.23%) patients who did not receive screening. It would be better if the authors introduce the indications for CTA that they applied in the article, because proper indications can decrease the missed diagnosis rate of BCVI.
Second, in the study, the records of patients who did not undergo screening were followed for 2 years to ensure that occult VAI was not missed. However, many previous studies have founded that some VAI without treatment can resolve at follow-ups.5–9 Scott et al5 found that 97% patients with VAI who did not receive treatment had stable, improved, or resolved injuries on final imaging. In the study of Desouza et al,8 85.7% VAI that were not treated with any medical or procedural therapy demonstrated improvement, and 14.3% was stable. Therefore, if occult VAI improve or resolve at follow-ups, diagnosis of VAI will not be made based on the records of the patients. Thus, some asymptomatic VAI were probably neglected in the patients who did not receive angiography in the study.
At last, concurrent BCI was identified as a risk factor for VAI in the study. However, in our opinion, it is unpractical to consider it as an indication for CTA of vertebral arteries after trauma. Because diagnosis of BCI is also largely depended on CTA. Thus, setting it as an indication for CTA of vertebral arteries is not helpful to decrease risks that include radiation exposure and nephrotoxicity.