Restriction Spectrum Imaging Models for Ovarian Cancer Using High-Resolution DWI

Motivation: Diffusion-weighted Imaging (DWI) has been added to standard ovarian MRI protocols to improve lesion characterization. Restriction spectrum imaging (RSI) is an advanced DWI model which may improve pre-surgical evaluation of ovarian lesions. Goal(s): To develop ovarian-specific, multi-exponential RSI models which differentiate benign, borderline, and malignant ovarian lesions. Approach: Bi-, tri-, and tetra-exponential RSI models were calculated using high-resolution DWI data from 12 pathology-confirmed ovarian lesions. Relative Bayesian Information Criterion (ΔBIC), fitting residuals, and compartment maps were used to identify the model which best characterized ovarian signal. Results: The tetra-exponential RSI model best described ovarian diffusion signal across lesion types. Impact: An ovarian-specific RSI model can enhance the utility of DWI in ovarian MRI, improve pre-surgical assessment, and most importantly, allow for the consideration of less radical surgical approaches for the management of ovarian lesions.