Regional difference in cerebral blood flow and oxidative metabolism in human cortex.

UNLABELLED: We sought to determine if there are regional differences in cerebral blood flow (CBF) and cerebral metabolic ratio for oxygen (CMRO2) in normal subjects during the resting state.

METHODS

Regional CBF, CMRO2 and oxygen extraction fraction (OEF) in 15 normal volunteers (mean age 58.8 +/- 8.2 yr) were measured during rest using PET and a 15O-gas steady-state technique.

RESULTS

CBF and CMRO2 in the visual cortex were significantly higher than those in other cortices. Additionally, OEF in the sensorimotor cortex was significantly lower than that in other cortical regions.

CONCLUSION

CBF and CMRO2 in the visual cortex are always high, and low OEF in the sensorimotor cortex exists even in resting state in normal subjects. We hypothesize that these regional functional differences would result in different resistances to degeneration.