Sci-Fri AM: Imaging - 08: Registration of In Vivo Medical Images to Digital Histopathology Images
AD Ward, Cathie Crukley, Charles A. McKenzie, Jacques Montreuil, JA Gómez, Madeleine Moussa, Glenn S. Bauman, Aaron Fenster · Medical Physics · 2010
Early and accurate diagnosis of prostate cancer enables minimally invasive therapies to cure the cancer with less morbidity. The purpose of this work is to non-rigidly register in vivo pre-prostatectomy prostate medical images to regionally-graded histopathology images from post-prostatectomy specimens, seeking a relationship between the multi parametric imaging and cancer distribution and aggressiveness. Our approach orients the physical slicing of the specimen to be parallel to the in vivo imaging planes, yielding a tractable 2D registration problem solved using a thin-plate spline method. Our technique is as follows: (1) apply a set of novel fiducial markers, visible on ex vivo MR and digital histopathology images; (2) use a magnetically tracked probe to localize the fiducials on the specimen and register the in vivo imaging plane orientation to the specimen space via a collected ex vivo MR image, specifying the insertion points of three pins on the desired specimen cutting plane; (3) use the pins to orient the specimen in a slotted forceps for slicing along the desired plane orientation. We measure slicing accuracy using a high-resolution (12.7 micron precision) mechanically-tracked probe. We measured a target registration error of 0.85 mm, a mean slicing plane marking error of 0.7 mm, and a mean slicing error of 0.6 mm; these results compare favourably with our 2.2 mm diagnostic MR image thickness. Qualitative evaluation of in vivo imaging-histopathology fusion reveals excellent anatomic concordance, including alignment between suspicious regions on MR and cancerous regions on digital histopathology. Declaration of concurrent submission: A full-length submission of this work has been made to Medical Image Computing and Computer-Assisted Intervention (MICCAI) 2010 (which has only a 20% acceptance rate), and a reduced version to AAPM 2010. We would like to request the permission of the Scientific Program Directors to share this work with the Canadian medial physics research community at COMP 2010.