Abstract

BACKGROUND: The application of computed tomographic angiography (CTA) for the diagnosis of brain death (BD) is limited because of the low sensitivity of the commonly used two-phase method consisting of assessing arterial and venous opacification at the 60th second after contrast injection. The hypothesis was that a reduction in the scanning delay might increase the sensitivity of the test. Therefore, an original technique using CTA was introduced and compared with catheter angiography as a reference.

MATERIAL AND METHODS: In a prospective multicenter trial, 84 clinically brain-dead patients were examined using CTA and catheter angiography. The sensitivities of original CTA technique, involving an arterial assessment at the 25th second and a venous assessment at the 40th second, and the standard CTA, involving an arterial and venous assessment at the 60th second, were compared to catheter angiography.

RESULTS: Catheter angiography results were consistent with the clinical diagnosis of BD in all cases. In comparison to catheter angiography, the sensitivity of original CTA technique was 0.93 (95%CI, 0.85–0.97; p<0.001) and 0.57 (95%CI, 0.46–0.68; p<0.001) for the standard protocol. The differences were statistically significant (p=0.03 for original CTA and p<0.001 for standard CTA). Decompressive craniectomy predisposes to a false-negative CTA result with a relative risk of 3.29 (95% CI, 1.76–5.81; p<0.001).

CONCLUSIONS: Our original technique using CTA for the assessment of the cerebral arteries during the arterial phase and the deep cerebral veins with a delay of 15 seconds is a highly sensitive test for the diagnosis of BD. This method may be a better alternative to the commonly used technique.

Keywords: Angiography, Digital Subtraction, Brain Death, Cerebral Angiography, decompressive craniectomy, Intracranial Hypertension, multidetector computed tomography