Abstract
The accuracy of the Cobb measurement is essential for the diagnosis and treatment of scoliosis. Manual measurement is however influenced by the observer variability hence affecting progression evaluation. In this paper, we propose a fully automatic Cobb measurement method to address the accuracy issue of manual measurement. We improve the U-shaped network based on the multi-scale feature fusion to segment each vertebra. To enable multi-scale feature extraction, the convolution kernel of the U-shaped network is substituted by the Inception Block. To solve the problem of gradient disappearance caused by the widening of the network structure from the Inception Block, we propose using Res Block. CBAM (Convolutional Block Attention Module) can help the network judges the importance of the feature map to modify learning weight. Also, to further enhance the accuracy of feature extraction, we add the CBAM to the U-shaped network bottleneck. Finally, based on the segmented vertebrae, the efficient automatic Cobb angle measurement method is proposed to estimate the Cobb angle. In the experiments, 75 spinal X-ray images are tested. We compare the proposed U-Shaped network with the state-of-the-art methods including DeepLabV3 + , FCN8S, SegNet, U-Net, U-Net + + , BASNet, and U2Net for vertebra segmentation. Our results show that compared to these methods, the Dice coefficient is improved by 32.03%, 33.58%, 12.42%, 5.65%, 4.55%, 4.42%, and 3.27%, respectively. The CMAE of the calculated Cobb measurement is 2.45°, which is lower than the average error of 5–7° of manual measurement. The experimental results indicate that the improved U-shaped network improves the accuracy of vertebra segmentation. The proposed efficient automatic Cobb measurement method can be used in clinics to reduce observer variability.
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References
Hefti F et al (2013) Pathogenesis and biomechanics of adolescent idiopathic scoliosis (AIS). J Children’s Orthop 7(1):17–24
Little JP, Izatt MT, Labrom RD et al (2013) An FE investigation simulating intra-operative corrective forces applied to correct scoliosis deformity. Scoliosis 8(1):9
Cobb JR (1947) Outline for the study of scoliosis. Instruct Course Lect 5
Asher MA, Burton DC (2006) Adolescent idiopathic scoliosis: natural history and long term treatment effects. Scoliosis 1(1):2–2
Weinstein SL, Dolan LA, Cheng JCY et al (2008) Adolescent idiopathic scoliosis. Lancet 371(9623):1527–1537
Vrtovec T, Pernu F, Likar B (2009) A review of methods for quantitative evaluation of spinal curvature. Eur Spine J 18(5):593–607
Pruijs JEH, Hageman MAPE, Keessen W et al (1994) Variation in Cobb angle measurements in scoliosis. Skelet Radiol 23(7):517–520
Wu H et al (2017) Automatic landmark estimation for adolescent idiopathic scoliosis assessment using BoostNet. International Conference on Medical Image Computing and Computer-Assisted Intervention Springer, Cham
Wu H, Bailey C, Rasoulinejad P et al (2018) Automated comprehensive adolescent idiopathic scoliosis assessment using MVC-Net. Med Image Anal 48:1–11
Lw A et al (2019) Accurate automated Cobb angles estimation using multi-view extrapolation net. Med Image Anal 58:101542
Fu X et al (2020) An automated estimator for Cobb angle measurement using multi-task networks. Neural Comput Appl 1–7
Zhang J, Lou E, Hill DL et al (2010) Computer-aided assessment of scoliosis on posteroanterior radiographs. Med Biol Eng Comput 48(2):185–195
Zhang J, Lou E, Le LH et al (2009) Automatic Cobb measurement of scoliosis based on fuzzy hough transform with vertebral shape prior. J Digit Imaging 22(5):463–472
Sardjono TA, Wilkinson MHF, Veldhuizen AG et al (2013) Automatic Cobb angle determination from radiographic images. Spine 38(20):1256–1262
Anitha H, Karunakar AK, Dinesh KVN (2014) Automatic extraction of vertebral endplates from scoliotic radiographs using customized filter. Biomed Eng Lett 4(2):158–165
Long J, Shelhamer E, Darrell T (2015) Fully convolutional networks for semantic segmentation. Proceedings of the IEEE conference on computer vision and pattern recognition. 3431–3440
Ronneberger O, Fischer P, Brox T (2015) U-Net: Convolutional networks for biomedical image segmentation. International Conference on Medical image computing and computer-assisted intervention. Springer, Cham, 234–241
Zhou Z, Siddiquee MMR, Tajbakhsh N et al (2018) Unet++: a nested u-net architecture for medical image segmentation. Deep learning in medical image analysis and multimodal learning for clinical decision support. Springer, Cham, p 3–11
Zhou Z et al (2020) UNet++: redesigning skip connections to exploit multiscale features in image segmentation. IEEE Trans Med Imaging 39(6):1856–1867
Qin X et al (2019) BASNet: boundary-aware salient object detection. 2019 IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), IEEE
Qin X et al (2020) U2-Net: going deeper with nested U-structure for salient object detection. Pattern Recognit 106:107404
Fang L, Liu J, Liu J, et al (2018) Automatic segmentation and 3D reconstruction of spine based on FCN and marching cubes in CT volumes. 2018 10th International Conference on Modelling, Identification and Control (ICMIC), IEEE. 1–5
Horng MH, Kuok CP, Fu MJ et al (2019) Cobb angle measurement of spine from X-ray images using convolutional neural network. Comput Math Methods Med
Tan Z, Yang K, Sun Y et al (2018) An automatic scoliosis diagnosis and measurement system based on deep learning. 2018 IEEE International Conference on Robotics and Biomimetics (ROBIO), IEEE, p 439–443
Wang L et al (2021) Evaluation and comparison of accurate automated spinal curvature estimation algorithms with spinal anterior-posterior X-ray images: the AASCE2019 challenge. Med Image Anal 72(1):1
Lei T et al (2020) Medical image segmentation using deep learning: a survey
Szegedy C, Ioffe S, Vanhoucke V et al (2017) Inception-v4, inception-resnet and the impact of residual connections on learning. Thirty-First AAAI Conference on Artificial Intelligence
He K, Zhang X, Ren S, et al (2016) Deep residual learning for image recognition. Proceedings of the IEEE conference on computer vision and pattern recognition, p 770–778
He K, Zhang X, Ren S et al (2016) Identity mappings in deep residual networks. European conference on computer vision, Springer, Cham, p 630–645
Hu J, Shen L, Sun G (2018) Squeeze-and-excitation networks. Proceedings of the IEEE conference on computer vision and pattern recognition, p 7132–7141
Woo S, Park J, Lee J Y, et al (2018) CBAM: convolutional block attention module. Proceedings of the European Conference on Computer Vision (ECCV). 3–19
Chen L C, Zhu Y, Papandreou G, et al., “Encoder-decoder with atrous separable convolution for semantic image segmentation,” Proceedings of the European conference on computer vision (ECCV). 801–818 (2018).
Badrinarayanan V, Kendall A, Cipolla R (2017) SegNet: a deep convolutional encoder-decoder architecture for image segmentation. IEEE Transactions on Pattern Analysis & Machine Intelligence. 1–1
Acknowledgements
This work was funded by the National Natural Science Foundation of China (Grant No. 62063034). The authors would like to express their gratitude to EditSprings (https://www.editsprings.cn/) for the expert linguistic services provided.
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Zhao, Y., Zhang, J., Li, H. et al. Automatic Cobb angle measurement method based on vertebra segmentation by deep learning. Med Biol Eng Comput 60, 2257–2269 (2022). https://doi.org/10.1007/s11517-022-02563-7
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DOI: https://doi.org/10.1007/s11517-022-02563-7