Improving the efficiency of spine region segmentation using an ensemble of pre-trained neural networks
Abstract
Background: The accuracy of segmentation of vertebrae in X-ray images is critical for clinical decisions as the manual method is laborious. The use of deep learning is complicated by low contrast, noise, and patient position artifacts. These negative factors make a single neural network unreliable. Thus, to improve the accuracy and efficiency of segmentation, regardless of the quality of X-ray images, there is a need for an ensemble of neural networks that compensates for the individual shortcomings of the models by aggregating their results.
Objectives: Increasing the accuracy and efficiency of segmentation of a spinal region consisting of four vertebrae (Th8, Th9, Th10, Th11) in X-ray images by using an ensemble of pre-trained neural networks.
Materials and methods: Two datasets were used for the experiments: the first set with 183 images was distributed in the ratio of 70% / 10% / 20% for training, validation, and testing, in turn, the second set of 58 images was used exclusively for the final assessment of the generalization ability of the ensemble on new data. In the process of research, segmentation accuracy with and without augmentation was first compared, after which the 10 best from the initial 20 neural networks were selected for further use, and five ensemble algorithms were used for mask aggregation.
Results: For the ensemble of pre-trained neural networks, the best result was shown by soft voting. Comparing the obtained result with the results presented by Koniukhov et al. (2024), the improvement was 3.06%. This indicator clearly confirms the effectiveness of using pre-trained networks for segmentation of the spine area.
Conclusions: Soft voting for an ensemble of pre-trained neural networks demonstrated the greatest improvement in segmentation accuracy compared to other methods. Aggregating knowledge from 10 models successfully eliminated the limitations of individual models. The use of an ensemble of pre-trained neural networks improved segmentation accuracy for both the test data from the first dataset and the data from the second dataset. Such results confirm the feasibility of applying the proposed ensemble-based approach to chest X-ray radiographs for vertebrae segmentation in medical imaging tasks.
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Copyright (c) 2026 V. D. Koniukhov, O. M. Morgun, K. E. Nemchenko

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