Fig. 1

Axial celloidin sections. a The axial section through the bladder prostatic groove. b The section through the upper and middle prostate. Note that the capsule and the levator fascia adhered together at lateral aspect of prostate (green arrow). c The section through the prostatic apex. d The section through the membranous urethra. Blue arrow indicated the position where DVC (dorsal vascular complex) and CS (cavernous supply, circled by white dots) were separated by posterolateral portion of SS (striated sphincter). This portion of SS was attached to the outlet of LAM (Levator ani muscle). Black, white, red and yellow triangles indicated capsule, levator fascia, anterolateral branch of prostatic artery in DVC and nerves in DVC respectively; white arrows showed fascia proper of rectum; yellow arrows indicated nerves in NVB; broad red arrow indicated posterior-lateral branch of prostatic artery in NVB; red arrow indicated middle rectal artery; the prostatic supply was circled by red dots; the rectal supply was circled by black dots. PNVB, pelvic neurovascular bundle; PF, pelvic fascia; SV, seminal vesicles; MR, mesorectum; CM, circular muscle of detrusor; DA, detrusor apron; PH, penile hilum; V (blue), veins in DVC; V (white), veins in NVB