Zonal anatomy of the prostate

Transition zone and peripheral zone on (a) T2-weighted magnetic resonance imaging and (b) ultrasound.

AFS: anterior fibromuscular stroma; PZ: peripheral zone; TZ: transition zone.

Reproduced with permission from: McLaughlin, PW, Troyer, S, Berri, S, et al. Functional anatomy of the prostate: Implications for treatment planning. Int J Radiation Oncology Biol Phys 2005; 63:479. Copyright ©2005 Elsevier.