Abstract
Chest X-ray (CXR) imaging is not particularly easy to interpret, due to the subtle appearance of the disease on CXR, and is prone to inter-observer variation, it is still regarded as the main diagnostic imaging modality for pneumonia, worldwide. Despite the promising results of deep learning models for automated pneumonia diagnosis, current convolutional architectures use only a single depth-based feature representation, and are mostly opaque, non-interpretable classifiers, which compromises the reliability and trust in clinical use. In this paper, we present PneumoFusion-Net, a multi-level convolutional feature extraction coupled with channel and spatial attention refinement framework to focus on the regions of the lungs relevant for diagnosis and ignore irrelevant background information. The extracted features from the shallow, intermediate and deep layers of a ResNet50 backbone are further refined using attention modules and merged into a unified representation for subsequent classification, while the Grad-CAM is directly incorporated in the pipeline to produce visual explanations for each prediction. The proposed model was trained and tested on the Kaggle chest X-ray pneumonia dataset which is publicly available consisting of 5,856 images. Experimental results show that the PneumoFusion-Net obtains test accuracy of 92.00%, precision of 0.92, recall of 0.92 and F1 of 0.92, while has a significantly smaller train-test accuracy gap of 2.60% compared to the VGG16, ResNet50, DenseNet121 and MobileNetV2 baselines, showing better generalization performance. The results indicate that multi-level attention fusion and built-in explainability are a practical and clinically reliable approach to automated screening of pneumonia.
References
- An, Q., Chen, W., & Shao, W. (2024). A deep convolutional neural network for pneumonia detection in X-ray images with attention ensemble. Diagnostics, 14(4), 390.
- Siddiqi, R., & Javaid, S. (2024). Deep learning for pneumonia detection in chest x-ray images: A comprehensive survey. Journal of imaging, 10(8), 176.
- Singh, S., Kumar, M., Kumar, A., Verma, B. K., Abhishek, K., & Selvarajan, S. (2024). Efficient pneumonia detection using Vision Transformers on chest X-rays. Scientific reports, 14(1), 2487.
- Chen, S., Ren, S., Wang, G., Huang, M., & Xue, C. (2023). Interpretable CNN-multilevel attention transformer for rapid recognition of pneumonia from chest X-ray images. IEEE Journal of Biomedical and Health Informatics, 28(2), 753-764.
- Colin, J., & Surantha, N. (2025). Interpretable deep learning for pneumonia detection using chest x-ray images. Information, 16(1), 53.
- Kaya, M., & Cetin-Kaya, Y. (2024). A novel ensemble learning framework based on a genetic algorithm for the classification of pneumonia. Engineering Applications of Artificial Intelligence, 133, 108494.
- Saranyaraj, D., Shrinaath, V., Nayak, A., & Vishal, R. (2025). PneuNet: a lightweight convolutional neural network with multiscale feature fusion for automated pneumonia detection from chest X-rays. Frontiers in Medicine, 12, 1713587.
- Mustapha, B., Zhou, Y., Shan, C., & Xiao, Z. (2025). Enhanced pneumonia detection in chest X-rays using hybrid convolutional and vision transformer networks. Current Medical Imaging, 21(1), e15734056326685.
- Shahi, K., & Bagale, A. (2025). Weakly supervised pneumonia localization from chest X-rays using deep neural network and Grad-CAM explanations. arXiv preprint arXiv:2511.00456.
- Mahtabi, B., Nasr-Esfahani, E., & Yaraghi, S. (2026). Parameter-efficient deep learning for pneumonia detection on chest X-rays: A comparative evaluation of explainable AI methods. medRxiv, 2026-07.
- Slimi, H., Balti, A., Abid, S., & Sayadi, M. (2025). Trustworthy pneumonia detection in chest X-ray imaging through attention-guided deep learning. Scientific Reports, 15(1), 40029.
- Ridwan, R. (2025). XAI-Guided Analysis of Residual Networks for Interpretable Pneumonia Detection in Paediatric Chest X-rays. arXiv preprint arXiv:2507.18647.
- Vyas, R., & Khadatkar, D. R. (2025). Ensemble of deep learning architectures with machine learning for pneumonia classification using chest X-rays. Journal of Imaging Informatics in Medicine, 38(2), 727-746.
- Tripathy, B., Khan, S., Bebortta, S., Kamal, A., Tripathy, S. S., Fazil, M., & Albarrak, A. M. (2025). TL-PneuNet: a transfer learning-based pneumonia classification framework. Scientific Reports, 15(1), 40307.
- Jahanian, M., Karimi, A., Eraghi, N. O., & Zarafshan, F. (2026). AXNet: Attention-enhanced X-ray network for pneumonia detection. Biomedical Signal Processing and Control, 118, 109618.
- An, Q., Chen, W., & Shao, W. (2024). A deep convolutional neural network for pneumonia detection in X-ray images with attention ensemble. Diagnostics, 14(4), 390.
- Huang, K. A., Choudhary, H. K., Santiago, A., & Prakash, N. S. (2025). Squeeze-and-Excitation Enhanced Convolutional Neural Networks for Multi-class Pneumonia Classification on Chest Radiographs. Cureus, 17(12).
- Shavkatovich Buriboev, A., Abduvaitov, A., & Jeon, H. S. (2025). Binary classification of pneumonia in chest X-ray images using modified contrast-limited adaptive histogram equalization algorithm. Sensors, 25(13), 3976.
- Saber, A., Fateh, A., Parhami, P., Siahkarzadeh, A., Fateh, M., & Ferdowsi, S. (2025). Efficient and accurate pneumonia detection using a novel multi-scale transformer approach. Sensors, 25(23), 7233.
- Aljuaid, H., Adlan, H., Alkebsi, B., Alfurhood, B. S., Liotta, A., & Cavallaro, L. (2026). An experimental comparison of deep learning models for pneumonia classification from chest X-ray images. Biomedical Signal Processing and Control, 112, 108742.
- Mooney, P. (2018). Chest X-ray images (pneumonia) [Data set]. Kaggle. https://www.kaggle.com/datasets/paultimothymooney/chest-xray-pneumonia/data




