Fig. 3

Schematic of the four major types of protocol of zonal segmentation. Type A: articles for which “central gland” included CZ, TZ and AFMS. Type B: articles for which “central gland” included TZ and CZ. No details for AFMS. Type C: articles which did not provide details for AFMS, CZ or CG. CZ seemed to be mostly segmented PZ, while AFMS seemed to be mostly segmented with TZ, usually called “CG”. Type D: articles which did not provide details for AFMS or CZ. CZ and AFMS seemed to be mostly segmented with PZ. CZ central zone, TZ transition zone, AFMS anterior fibro-muscular stroma, PZ peripheral zone, CG central gland