An Improved Medical Image Fusion for Efficient Diagnostic Imaging Using Deep Learning and Gradient-Based Quality Assessment
Received: 18 February 2025 | Revised: 4 May 2025 and 25 May 2025 | Accepted: 30 May 2025 | Online: 1 January 2026
Corresponding author: Ahmad Taher Azar
Abstract
Advancements in Deep Learning (DL) have significantly contributed to progress in image processing and pattern recognition, particularly in the medical imaging domain. This study proposes an improved DL-based fusion method for multi-modal medical images, referred to as Deep Learning Medical Image Fusion (DMF). The proposed technique integrates Convolutional Neural Networks (CNNs) with three conventional image fusion methods to generate enhanced fused outputs across various medical imaging modalities. By leveraging gradient-based quality assessments, including visibility, consistency, and exposure mapping, the DMF method effectively synthesizes multi-exposure images, resulting in high-resolution outputs with improved structural clarity and visual consistency. Unlike traditional fusion approaches, the proposed model capitalizes on gradient variations among multiple exposures to guide fusion decisions, leading to improved diagnostic relevance. The performance of the DMF technique is validated through comprehensive experiments, involving Magnetic Resonance Imaging-Computed Tomography (MRI-CT) and MRI-Positron Emission Tomography (MRI-PET) image pairs, which demonstrated its superior effectiveness and practicality in healthcare imaging and diagnostic applications.
Keywords:
medical image fusion, deep learning, multi-modal imaging, convolutional neural networks, gradient-based quality assessment, image processing, diagnostic imaging, healthcare applicationsDownloads
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