Feasibility of the fat-suppression image-subtraction method using deep learning for abnormality detection on knee MRI

Shusuke Kasuya; Tsutomu Inaoka; Akihiko Wada; Tomoya Nakatsuka; Koichi Nakagawa; Hitoshi Terada

doi:10.5114/pjr.2023.133660

Feasibility of the fat-suppression image-subtraction method using deep learning for abnormality detection on knee MRI

Pol J Radiol. 2023 Dec 8:88:e562-e573. doi: 10.5114/pjr.2023.133660. eCollection 2023.

Authors

Shusuke Kasuya¹, Tsutomu Inaoka¹, Akihiko Wada², Tomoya Nakatsuka¹, Koichi Nakagawa³, Hitoshi Terada¹

Affiliations

¹ Department of Radiology, Toho University Sakura Medical Center, Sakura, Japan.
² Department of Radiology, Juntendo University, Tokyo, Japan.
³ Department of Orthopaedic Surgery, Toho University Sakura Medical Center, Sakura, Japan.

Abstract

Purpose: To evaluate the feasibility of using a deep learning (DL) model to generate fat-suppression images and detect abnormalities on knee magnetic resonance imaging (MRI) through the fat-suppression image-subtraction method.

Material and methods: A total of 45 knee MRI studies in patients with knee disorders and 12 knee MRI studies in healthy volunteers were enrolled. The DL model was developed using 2-dimensional convolutional neural networks for generating fat-suppression images and subtracting generated fat-suppression images without any abnormal findings from those with normal/abnormal findings and detecting/classifying abnormalities on knee MRI. The image qualities of the generated fat-suppression images and subtraction-images were assessed. The accuracy, average precision, average recall, F-measure, sensitivity, and area under the receiver operator characteristic curve (AUROC) of DL for each abnormality were calculated.

Results: A total of 2472 image datasets, each consisting of one slice of original T1WI, original intermediate-weighted images, generated fat-suppression (FS)-intermediate-weighted images without any abnormal findings, generated FS-intermediate-weighted images with normal/abnormal findings, and subtraction images between the generated FS-intermediate-weighted images at the same cross-section, were created. The generated fat-suppression images were of adequate image quality. Of the 2472 subtraction-images, 2203 (89.1%) were judged to be of adequate image quality. The accuracies for overall abnormalities, anterior cruciate ligament, bone marrow, cartilage, meniscus, and others were 89.5-95.1%. The average precision, average recall, and F-measure were 73.4-90.6%, 77.5-89.4%, and 78.4-89.4%, respectively. The sensitivity was 57.4-90.5%. The AUROCs were 0.910-0.979.

Conclusions: The DL model was able to generate fat-suppression images of sufficient quality to detect abnormalities on knee MRI through the fat-suppression image-subtraction method.

Keywords: 2-dimensional convolutional neural network; MRI; deep learning; fat suppression; knee; subtraction image.