Contrast-ing opinions: biparametric versus multiparametric prostate MRI

摘要: Dear Editor, I note the short communication by Turkbey and Choyke providing a succinct summary of updated PI-RADS system for prostate MRI acquisition interpretation in September-October 2015 issue Diagnostic Interventional Radiology. (1). An interesting argument has also been presented against routine use dynamic contrast-enhanced (DCE) sequences suggested therein multiparametric magnetic resonance imaging (mpMRI) evaluation (2). The “multi” mpMRI never strictly defined but is taken to mean addition functional sequence(s) standard anatomical imaging. In reflecting evolving diagnostic role mpMRI, recently Prostate Imaging Reporting Data System (PIRADS) 2.0 removed recommendation spectroscopy reduced DCE. The limitations DCE have well set out authors, namely cost its limited specificity. Unlike breast MRI, curve-typing because most tumors demonstrate type II curve (3) number benign conditions such as prostatitis prostatic hyperplasia can Type III curve. Essentially recommendations relegate that assessment indeterminate lesions peripheral zone, even then there must be corresponding abnormality on another sequence. However, before dismissing completely we need appreciate advantages it may bring. Contrast often essential follow-up patients undergoing ablative focal therapy procedures. Furthermore, play when technical failure diffusion-weighted which, aside from known presence metalwork, difficult prospectively predict. Indeterminate seen up 30% studies using old guidelines (4), version will increase tendency radiologists call PIRADS-3 (5). absence employing patient-recall system, or having supervising radiologist make on-table decisions giving contrast, these are valid reasons DCE. At our institution (45-minute time slot) initial, baseline biparametric (bp) active surveillance (30 minutes), thus, three scanned latter protocol every two former. Given increasing demand this potentially significant impact work flows ancillary costs DCE. bpMRI quick “screening” examination biopsy-naive therefore becomes an attractive proposition. current case based anecdotal retrospective evaluations; hopefully future prospective randomized help resolve issue.