Cerebral blood flow measurement in children with sickle cell disease using continuous arterial spin labeling at 3.0-Tesla MRI

BACKGROUND AND PURPOSE: Cerebral infarction is an important complication of sickle cell disease (SCD) and occurs in one third of the patients with SCD. The risk of infarction is commonly attributed to the hyperemia that is associated with anemia and reduces the cerebral vascular reserve. We measured regional cerebral blood flow (rCBF) by continuous arterial spin labeling MRI, which is a noninvasive method that does not require ionizing radiation. The purpose of this study was to examine rCBF in children with SCD and compare it with rCBF in healthy children. METHODS: rCBF was measured at 3-T continuous arterial spin labeling MRI in 24 neurological normal patients with SCD and in 12 healthy children matched for ethnicity and age (mean age in both groups 13 years). rCBF was calculated for 6 vascular territories (left and right anterior, middle and posterior cerebral artery). Asymmetry in rCBF was evaluated by measuring differences in flow between left and right hemispheres. The definition of asymmetry (>11.7 mL/100 g/min) was based on a repeatability study performed in 6 healthy adults. RESULTS: The rCBF was of similar magnitude in patients with SCD and control subjects in the frontal, middle, and posterior territories. The majority of patients with SCD (58%) demonstrated a left-right asymmetry of rCBF in one or more vascular territories, whereas none of the control subjects did. CONCLUSIONS: In contrast to previous studies, we found no difference in cerebral blood flow between patients and control subjects. We did observe an asymmetry in rCBF in the majority of patients with SCD that was not present in healthy control subjects