Fig. 4From: A convenient, reliable, and fast acoustic pressure field measurement method for magnetic resonance-guided high-intensity focused ultrasound systems with phased array transducersThe peak positive (p+) and peak negative (p−) pressures as a function of electronic beam steering distance along a axial direction (Z-axis) and b radial direction (X-axis). The maximum steering distances used to perform the larger volume and smaller volume scans are indicated with dashed and solid vertical lines, respectively. These measurements were obtained outside the magnet room using the standard hydrophone measurement method at a nominal acoustic power of 100 WBack to article page