Aneurysmal 99m Tc-HMPAO Uptake in Brain Death

A 41-year-old man was admitted to hospital due to sudden loss of consciousness. A regional brain perfusion SPECT/low-dose CT showed abnormal 99m Tc-HMPAO uptake in the right hemisphere frontotemporally without any other supratentorial or infratentorial radiotracer uptake. A neuropathological examination disclosed a middle cerebral artery aneurysm. Presumably, vessel wall fibrosis prevented collapse. Multiple transmural dissections of the fibrotic aneurysmal wall were the source of the subarachnoid hemorrhage. This interesting image shows that radiotracer accumulation in cerebral artery aneurysms can be a diagnostic pitfall in brain death scintigraphy assessment.