TC-99M HMPAO BRAIN PERFUSION SPECT IN BRAIN-DEATH

Diagnosis of brain death must be certain to allow discontinuation of a rtificial ventilation and organ transplantation. Brain death is presen t when all functions of the brain stem have irreversibly ceased. Clini cal and electrophysiological criteria may be misinterpreted due to dru g intoxication, hypothermia or technical artefacts. Thus, if clinical assessment is suboptimal, reliable early confirmatory tests may be req uired for demonstrating absence of intracranial blood flow. We have ea sily carried out and interpreted Tc-99m HM-PAO SPECT in a consecutive series of 40 comatose patients with brain damage, without discontinuin g therapy. Brain death was diagnosed in 7 patients, by recognising abs ence of brain perfusion, as shown by no intracranial radionuclide upta ke. Ln patients in whom perfusion was seen on brain scans, HM-PAO SPEC T improved assessment of the extent of injury, which in general was la rger than suggested by CT.