A practical primer on PI-RADS version 2: a pictorial essay.

Multiparametric magnetic resonance imaging has become an established method for evaluating the prostate for clinically significant prostate adenocarcinoma. Criteria have been developed for categorizing MRI findings, the most frequently used of which is the PI-RADS system. The PI-RADS V2 document provides separate image interpretation and clinical grading sections. Within this article we give an overview of the integrated, algorithmic way, we approach prostate MRI, show images corresponding to each PI-RADS category, and provide several illustrative cases.