Multiparametric (mp) MRI is essentially any functional form of imaging used to supplement standard anatomical T1 and T2- weighted imaging.
The functional sequences of choice are dynamic contrast-enhanced (DCE) MRI and diffusion-weighted imaging (DWI), including the calculation of apparent diffusion co-efficient (ADC) maps.
Multiparametric MRI (mpMRI) can be briefly summarized as a method of trying to obtain an ideal three-dimensional (3D) prostate image by combining T2-weighted (T2WI), diffusion weighted (DWI), dynamic contrast enhanced (DCEI) and, if desired, MR spectroscopy (MRSI) images.
Another technique, MR spectroscopy has recently fallen out of favor.
Inclusion of all three of these functional parameters achieves a positive predictive value for prostate cancer of 98%, compared to the detection rate of 68% for T2W MRI alone.
mpMRI is considered in men with indications for prostate biopsy with an elevated PSA to reduce the number of men undergoing biopsy and will reduce the detection of indolent disease and thus the risks of over detection and over treatment.
It can be integrated with transrectal ultrasound imaging which has an increased rate of high-grade lesion detection.
mpMRI reduces unnecessary biopsies while being able to detect clinically significant disease.
MpMRI has a role in initial staging of intermediate disease and high risk patients by detecting extraprostatic extension, seminal vesicle invasion, and lymph node invasion.
MpMRI is helpful for selecting men suitable for nerve sparing radical prostatectomy.