Apparatus for Histological Validation of In Vivo and Ex Vivo Magnetic Resonance Imaging of the Human Prostate

Abstract

This article describes apparatus to aid histological validation of magnetic resonance imaging studies of the human prostate. The apparatus includes a 3D-printed patient-specific mold that facilitates aligned in vivo and ex vivo imaging, in situ tissue fixation, and tissue sectioning with minimal organ deformation. The mold and a dedicated container include MRI-visible landmarks to enable consistent tissue positioning and minimize image registration complexity. The inclusion of high spatial resolution ex vivo imaging aids in registration of in vivo MRI and histopathology data.

A system using patient‐specific 3D‐printed molds to spatially align in vivo MRI with ex vivo MRI and whole‐mount histopathology for prostate cancer research

“…On the other hand, strategies based on ExV have only been evaluated in relatively small numbers of prostate specimens, often lack standardization of the experimental design (e.g., to achieve consistent positioning of the specimen with respect to InV), or lack integration into the clinical workflow. Recently, there have been initial investigations of alignment strategies that combine the advantages of patient‐specific molds with ExV, but only proof‐of‐concept results have been reported thus far.…”

IMPROD biparametric MRI in men with a clinical suspicion of prostate cancer (IMPROD Trial): Sensitivity for prostate cancer detection in correlation with whole‐mount prostatectomy sections and implications for focal therapy

“…As expected, the sensitivity increased with decreasing resolution of MRI datasets to larger voxel size (125.00 mm 3 ). Multiple prior studies evaluated the accuracy of prostate MRI at the ROI level, ranging from 6 ROIs to 30 ROIs, and on the voxel level . In a prior study by Priester et al, tumor extent was underestimated by more than 10 mm in 2/3 of cases, while in Le Nobin et al, underestimation was found to be somewhat smaller, suggesting a 9 mm safety margin in a study where the distance measurement was based on coregistration to histology.…”

“…Moreover, multiple research groups have already used 3D‐printed molds and ex vivo imaging to improve registration. Although these methods appear to improve coregistration accuracy, multiple challenges remain . In the IMPROD trial, all prostatectomy specimens were processed identically (Supporting Fig.…”

“…A wide range of accuracy for PCa lesion detection and volume estimation has been reported . Multiple factors such as patient population, MRI acquisition and reporting protocols, and reference methods for standard coregistration of whole‐mount prostatectomy sections to in vivo MRI have major effects on the results.…”

“…Multiple factors such as patient population, MRI acquisition and reporting protocols, and reference methods for standard coregistration of whole‐mount prostatectomy sections to in vivo MRI have major effects on the results. Multiple studies have also evaluated and improved coregistration of whole‐mount prostatectomy sections to in vivo MRI . However, external validation and implementation of methodology by other centers is limited by the lack of public access to datasets.…”