Fig 5.

Regional changes in CBF compared with extent of AV shunt. Δ = contralateral − ipsilateral CBF in measured regions of interest in white matter near the AVM, the cortex near the AVM, the thalamus, and the basal ganglia. A, Cortical gray matter CBF Δ values are negatively but weakly correlated with percent AV shunt and are not significant. (B) Δ values in white matter (R² = 0.70, F = 11.58, P = .02) are negatively correlated (blood flow in adjacent ipsilateral white matter increases as percent shunt increased). Basal ganglia Δ values (C) show little change in CBF with the size of the AV shunt, but thalamic CBF (D) appears to decrease ipsilaterally as percent AV shunt increases (R² = 0.74, F = 14.19, P = .01).