Young Ro Kim1 and Jerrold L Boxerman2
1Radiology, MGH, Charlestown, MA, United States, 2Neuroradiology, Brown University, Providence, RI, United States
Previously, water exchange index (WEI) was proposed to quantify the rate of water movement across the blood-brain barrier (BBB). Although efficient and clinically applicable, the technique could not reliably provide voxelwise WEI maps due to the inadequate signal to noise ratio (SNR). In remedy of this shortcoming, we here present the relative WEI (rWEI) method, which enables voxelwise mapping of BBB water exchange while significantly reducing the acquisition time (< 10 min). To confirm the validity of the technique, the rWEI maps were acquired in post thrombectomy patients with unilateral infarct and compared with the WEI values.