SERIAL CHANGES IN REGIONAL BLOOD-FLOW IN THE CEREBRUM AND CEREBELLUM OF STROKE PATIENTS IMAGED BY TC-99(M)-HMPAO SPET

Luxury perfusion is a well-known phenomenon that can mask ischaemic le sions in patients with cerebral infarction, thus making diagnosis diff icult. In this study, we evaluated the incidence of luxury perfusion O ver a 3-week period following a stroke episode. The usefulness of cros sed cerebellar diaschisis (CCD) as a complementary feature in the diag nosis of cerebral infarction was also evaluated using Tc-99(m)-hexamet hylpropyleneamine oxime (Tc-99(m)-HMPAO) brain single photon emission tomography (SPET). Twelve patients diagnosed as having a hemispheric i schaemic stroke of the middle cerebral arterial territory were enrolle d in the study. Each patient underwent a total of four Tc-99(m)-HMPAO brain SPET examinations, 1 day, 1 week, 2 weeks and 3 weeks following the stroke episode. Our results show that the incidence of luxury perf usion was 67% (8/12) after 1 week, 75% (9/12) after 2 weeks and 83% (1 0/12) after 3 weeks. The incidence of CCD was 33% (4/12) after 1 day, 50% (6/12) after 1 week, 42% (5/12) after 2 weeks and 33% (4/12) after 3 weeks. We conclude that the detection of cerebral infarction is dif ficult 2 weeks or more after a stroke episode. The interval between th e stroke episode and examination must be considered when reading the T c-99(m)-HMPAO image. In addition, CCD may be helpful for the diagnosis of cerebral infarction within the first week after a stroke episode, especially in cases of an unidentified ischaemic region on the Tc-99(m )-HMPAO hemispheric image. However, the value of CCD is Limited 2 week s or more following the stroke episode.