AGE-DEPENDENCE OF LOCAL CEREBRAL BLOOD-FL OW - INVESTIGATIONS OF 4-YEAR-OLD TO 15-YEAR-OLD CHILDREN AND ADULTS WITH TC-99M-ECD

Aim: This present study deals with the question whether normal distrib ution of local cerebral blood flow (ICBF) agents in adults can be tran sferred to the age group of 4 to 15 years old children. Methods: 23 ch ildren (age: 4-15 years, mean 11 +/- 3 y) (group I) and 10 adults (age : 27-56 years, mean 45 +/- 10 y) (group II) without evidence of cerebr ovascular disease or other brain diseases underwent Tc-99m-ECD-SPECT i maging. Counts in the cortical ROIs were related to those of cerebella r ROIs (= 100%). Results: In group I, relative cortical activity excee ded that of group II, particularly in parietal (107.6 +/- 9.8 vs. 84.1 +/- 12.4%), frontal (97.7 +/- 6.7 vs. 79.4 +/- 8.9%), left temporal a reas (99.7 +/- 7.4 vs. 84.9 +/- 10.1%) and in the cingular cortex (112 .1 +/- 9.1 vs. 95.9 +/- 10.1%, p < 0.05). Cerebral activity uptake/inj ected dose/acquisition period was linearly correlated with age in grou p I (r = -0.78, p < 0.001). There was also a correlation of the relati ve local count density with age in 5 parietal ROIs (r = -0.42 to -0.57 ), in 2 frontal ROIs (r = -0.481, in 7 temporal ROIs (r = -0.42 to -0. 58) and in 2 occipital ROIs (r = -0.44). In 14 cortical regions relati ve Counts differed when subgroups of children aged 4-10 and 11-15 year s were analysed, Conclusion: There are systematic differences between 4 to 15 years old children and adults regarding the normal distributio n of ICBF. Diagnostic use of perfusion agents has to Consider the resp ective age-adjusted normal flow maps; respective normal ranges should be determined for age groups of 4-10 and of 11-15 years separately.