Performance Analysis of Deep Learning Models for Femur Segmentation in MRI Scan
Mengyuan Liu, Yixiao Chen, Anning Tian, Xinmeng Wu, Mozhi Shen, Tianchou Gong, Jeongkyu Lee
TL;DR
The paper evaluates four segmentation architectures (U-Net, Attention U-Net, U-KAN, and SAM 2) for femur segmentation in MRI, using 11,164 annotated scans. Under a unified training regime and an ensemble approach, Attention U-Net achieves the top overall Dice score, while U-KAN excels in small ROI regions such as the femoral shaft; SAM 2 performs competitively but does not surpass CNN-based models in most regions. The findings highlight the continuing strength of CNN-based methods for precise bone segmentation in MRI and underscore the value of attention and KAN enhancements, with dataset size and region size significantly influencing model performance. The results have practical implications for automated femur modeling in orthopedics and rehabilitation, guiding model selection and prompting further exploration with larger datasets.
Abstract
Convolutional neural networks like U-Net excel in medical image segmentation, while attention mechanisms and KAN enhance feature extraction. Meta's SAM 2 uses Vision Transformers for prompt-based segmentation without fine-tuning. However, biases in these models impact generalization with limited data. In this study, we systematically evaluate and compare the performance of three CNN-based models, i.e., U-Net, Attention U-Net, and U-KAN, and one transformer-based model, i.e., SAM 2 for segmenting femur bone structures in MRI scan. The dataset comprises 11,164 MRI scans with detailed annotations of femoral regions. Performance is assessed using the Dice Similarity Coefficient, which ranges from 0.932 to 0.954. Attention U-Net achieves the highest overall scores, while U-KAN demonstrated superior performance in anatomical regions with a smaller region of interest, leveraging its enhanced learning capacity to improve segmentation accuracy.
