Automated rotator cuff tear classification using 3D convolutional neural network

Abstract

Rotator cuff tear (RCT) is one of the most common shoulder injuries. When diagnosing RCT, skilled orthopedists visually interpret magnetic resonance imaging (MRI) scan data. For automated and accurate diagnosis of RCT, we propose a full 3D convolutional neural network (CNN) based method using deep learning. This 3D CNN automatically diagnoses the presence or absence of an RCT, classifies the tear size, and provides 3D visualization of the tear location. To train the 3D CNN, the Voxception-ResNet (VRN) structure was used. This architecture uses 3D convolution filters, so it is advantageous in extracting information from 3D data compared with 2D-based CNNs or traditional diagnosis methods. MRI data from 2,124 patients were used to train and test the VRN-based 3D CNN. The network is trained to classify RCT into five classes (None, Partial, Small, Medium, Large-to-Massive). A 3D class activation map (CAM) was visualized by volume rendering to show the localization and size information of RCT in 3D. A comparative experiment was performed for the proposed method and clinical experts by using randomly selected 200 test set data, which had been separated from training set. The VRN-based 3D CNN outperformed orthopedists specialized in shoulder and general orthopedists in binary accuracy (92.5% vs. 76.4% and 68.2%), top-1 accuracy (69.0% vs. 45.8% and 30.5%), top-1±1 accuracy (87.5% vs. 79.8% and 71.0%), sensitivity (0.94 vs. 0.86 and 0.90), and specificity (0.90 vs. 0.58 and 0.29). The generated 3D CAM provided effective information regarding the 3D location and size of the tear. Given these results, the proposed method demonstrates the feasibility of artificial intelligence that can assist in clinical RCT diagnosis.

Deep-learning framework and computer assisted fatty infiltration analysis for the supraspinatus muscle in MRI

“…Recently, deep learning technology has been adopted to address many unsolved scientific and technical problems, and it has been applied in medical image analysis in recent studies 23 , 24 . In particular, CNNs have shown promise as high-capacity parametric models for image analysis by using a large number of parameters derived from training data 1 , 25 , 26 .…”

Artificial intelligence for MRI diagnosis of joints: a scoping review of the current state-of-the-art of deep learning-based approaches

“…In 2020, another CNN also using a three-dimensional approach was described for automated rotator cuff tear detection on axial T1-weighted and sagittal and coronal fat-suppressed T2-weighted MR images [43]. The CNN employed a 2-class categorization into Fig.…”

Deep Learning for Orthopedic Disease Based on Medical Image Analysis: Present and Future

“…Unfortunately, the black box nature of deep learning has not been completely resolved, but there are some notable achievements [8]. As one of these achievements, in 2016, Zhou et al introduced a method explaining how a CNN makes a decision through class activation mapping [9], and this method is widely used in the field of medical artificial intelligence [10]. In a similar context, there are attempts to improve the explainability by improving the existing CNN architecture [11].…”