Detection of Rectal Gas Induced Artifacts in Diffusion Weighted MR Images

Motivation: Rectal gas in prostate causes image quality issues in EPI-DWI imaging and precludes use of DWI for tumor assessment Goal(s): Reduce the number of distorted DWI exams in prostate MRI scans due to rectal gas by warning the user about its impact. Approach: Proposed method automatically delineates prostate gland, surrounding rectal gas, correlates morphological parameters such as gas volume and proximity of gas to prostate gland to predict probability of distortion occurring with logistic regression. Results: Logistic regression analysis indicates excellent AUC = 0.987 for prediction for DWI distortion due to rectal gas, with positive response in 29/31 cases. Impact: The study highlights that rectal gas-based impact on DWI image quality can be predicted using parameters affecting EPI-DW distortion. This will be useful for technologist to make informed choice for DWI acquisition scan planning.