Figure 3: Use of anatomical and stereotactic landmarks for visual registration of 3 sample mp-MRI targets located in the “gray zone.” This figure shows three schematic representations of prostate base, midgland and apex ((a); top to bottom) sections, represented by gray dashed lines on the sagittal and coronal views ((b); top and bottom, resp.). The standard 12 systematic biopsy (SB) cores are represented by dotted arrows. The red lesion is a typical anterior apex cancer; the blue lesion is right TZ cancer, and the purple lesion a PZ cancer located on the midline. All have a clinically significant volume. Visual registration of a mp-MRI target on the TRUS image can be helped by multiple anatomical landmarks or simple three-dimensional distances, both on the craniocaudal plane (ejaculatory ducts (), verumontanum (), distance from the apex ()), and on the axial plane (distance from the midline (); distance from the posterior surface of the gland (); presence of cystic () or benign nodular lesions () next to the target lesion).