Design of focused ultrasound phased arrays for prostate treatment

The design of phased arrays for transrectal ultrasound therapy of the prostate presents significant challenges due to anatomical constraints on the size and shape of the probe. To maximize the array performance under these constraints, the effect of array geometry was examined theoretically. Studies were conducted on spherical segment, cylindrical, and curved cylindrical arrays. Fields were computed by dividing the array elements into many point sources. The effectiveness of various configurations was evaluated by defining a parameter, G, as the ratio of the intensity at the desired focus to the maximum intensity of any unwanted lobes.