CO-57 AS A SPET TRACER IN THE VISUALIZATION OF ISCHEMIC BRAIN-DAMAGE IN PATIENTS WITH MIDDLE CEREBRAL-ARTERY STROKE

In PET studies we have shown the usefulness of cobalt radionuclides fo r the visualization and quantification of ischaemic damage in stroke. In the present study, we explored Co-57(2+) as a SPET tracer. Uptake o f radioactivity was estimated by using a cobalt enhancement ratio defi ned as the ratio of cobalt uptake in the affected region versus a simi lar volume in the non-affected contralateral side. Clinical status was assessed with the Orgogozo stroke score at the time of scanning and a t least 60 days after admission. Nineteen patients (11 men, 8 women) w ith a middle cerebral artery stroke were examined with Co-57(2+) SPET 0-30 days after stroke onset. Our investigations show enhanced cobalt uptake in the infarcted brain tissue in patients with a major stroke a nd little clinical improvement. There was a significant correlation be tween the cobalt enhancement ratio and the Orgogozo score at the time of scanning and discharge. Our results suggest that Co-57(2+) SPET is suitable for determining the extent of (possibly calcium-mediated) dam age in stroke and in the assessment of potential therapeutic intervent ions. ((C) 1998 Lippincoft-Raven Publishers).