Real-time ultrasound brain perfusion imaging with analysis of microbubble replenishment in acute XXXX .

@entity2500 @entity1 @entity63
Real-time ultrasound perfusion imaging (rt-UPI) allows visualization of microbubbles flowing through the cerebral microvasculature. We hypothesized that analysis of microbubble tissue replenishment would enable for characterization of perfusion deficits in @entity2500 . Twenty-three @entity1 (mean age 70.2    13.2 years, 9 weeks) were included. Sequential images of bubble replenishment were acquired by transcranial rt-UPI at low mechanical index immediately after microbubble destruction. Different parameters were calculated from regions of interest (ROIs): real-time time to peak (rt-TTP), rise rate (b), and plateau (A) of acoustic intensity, and A   b was used as an index of blood flow. Results were compared with diffusion-weighted and perfusion magnetic resonance imaging. Parameters of rt-UPI had lower values in ROIs of @entity63 as compared with normal tissue (b=0.58    0.40 versus 1.25    0.83; P=0.001; A=1.44    1.75 versus 2.63    2.31; P=0.05; A   b=1.14    2.25 versus 2.98    2.70; P=0.01). Real-time time to peak was delayed in @entity63 tissue (11.43    2.67 versus 8.88    1.66 seconds; P<0.001). From the analysis of receiver operating characteristic curves, b and A   b had the largest areas under the curve with optimal cutoff values of b<0.76 and A   b<1.91. We conclude that rt-UPI with analysis of microbubble replenishment correctly identifies @entity63 brain tissue in acute @entity2500 .
