The diagnosis of brain death - own experience

Abstract

BACKGROUND: The aim of this paper is a description of our experience with scintigraphic detection of brain death.
MATERIAL AND METHODS: Thirty-four patients were studied from February 2003 to June 2006. We performed brain scintigraphic examination utilising ^99mTc-HMPAO and a two-headed SPECT camera E.CAM. We used LEHR collimators. 15% energy window was centred around 140 keV. 650-750 MBq of radiopharmaceutical was injected as a bolus. Then dynamic scintigraphy of the head and neck was done in an anterior projection - 2 s per frame for 60 s. Then static scintigraphy of the head in four projections followed (anterior, both lateral and posterior views), for 4 minutes per view.
RESULTS: A typical picture of brain death on planar dynamic and static scintigrams showed an absence of perfusion and radiopharmaceutical accumulation in both cereberal and cerebral hemispheres and brain stem. Radioactivity in the area of the scalp and face could be present. Borderline findings, which demanded careful interpretation, were the cases with preservation of minimal cerebral perfusion and simultaneous absence of radiopharmaceutical accumulation in its parenchyma and cutoff of tracer accumulation in cerebral parenchyma only supraor infratentorial.
CONCLUSIONS: Cerebral perfusion scintigraphy is the most contributing factor for the diagnosis of brain death in patients after cranial trauma with subsequent neurosurgical operation, when angiography is often unsuitable. In these situations perfusion scintigraphy is able to show the absence of radiopharmaceutical accumulation in cerebral tissue. Scintigraphic detection of brain death gained an important role in new Czech legislation, and the demands of transplant centres for these examinations will certainly grow with the accrual of organ collections.