False Positive CT Angiography in Brain Death

Ancillary testing is frequently required in the determination of death by brain criteria, particularly in cases in which the clinical examination is drawn into question. Newer tests, such as computed tomographic angiography (CTA), have garnered enthusiasm for their ease of performance, but have not been validated as acceptable tests compared with a gold standard. We present a case of a 31-year-old patient who was felt to have cerebral circulatory arrest on CTA, but was subsequently found to have evidence of preserved cerebral blood flow on transcranial Doppler, thus precluding the diagnosis death by brain criteria. CTA is not a validated confirmatory test for cerebral circulatory arrest in brain death, and may be falsely positive. CTA should be studied further in comparison to validated tests, such as conventional angiography or single photon emission computed tomography (SPECT), before being accepted as a standard ancillary test in determining death by brain criteria.