Diffusion tensor magnetic resonance tractography of the prostate: feasibility for mapping periprostatic fibers

Objective: To evaluate the feasibility of diffusion tensor imaging (DTI) tractography of the prostate for mapping of periprostatic neurovascular anatomy.

Methods: Eight men with prostate cancer scheduled to undergo nerve-sparing robot-assisted radical prostatectomy (RARP) underwent endorectal multiparametric magnetic resonance imaging (MRI) of the prostate with DTI. Tract mapping was accomplished by positioning spherical regions of interest contiguously along the prostatic capsule at the prostatic apex, midgland, and base.

Results: DTI tractography of the prostate effectively visualized periprostatic fiber tract anatomy. There was no significant correlation between total tract number and prostate size, however (Spearman's coefficient = 0.33, P = .42). Variation in tract distribution existed. The total fiber mass was highest in the lower prostate hemisphere at the base of the prostate (mean = 36.9 vs 21.1, P = .0004) and in the upper hemisphere at the apex (mean = 41.6 vs 57.9, P = .006).

Conclusion: DTI tractography successfully visualized fiber tracts around the prostate. Gold standard anatomic correlation is needed.