Domain-Adaptive Transformer for Data-Efficient Glioma Segmentation in Sub-Saharan MRI
Ilerioluwakiiye Abolade, Aniekan Udo, Augustine Ojo, Abdulbasit Oyetunji, Hammed Ajigbotosho, Aondana Iorumbur, Confidence Raymond, Maruf Adewole
TL;DR
This work tackles domain shift in glioma MRI segmentation for Sub-Saharan Africa by proposing SegFormer3D+, a domain-adaptive transformer that combines histogram-based intensity harmonization, radiomics-guided stratification, and a frequency-aware encoder with dual attention. Pretrained on BraTS 2023 and fine-tuned on BraTS-Africa, the approach achieves superior Dice scores and boundary accuracy across heterogeneous scans, outperforming baselines such as nnU-Net and Swin-UNETR. Key contributions include an explicit preprocessing-and-architecture integration for cross-domain robustness and an ablation analysis quantifying each component's impact. The results highlight significant potential for reliable, equitable tumor delineation in resource-limited settings, with future work targeting self-supervised learning and broader SSA cohorts.
Abstract
Glioma segmentation is critical for diagnosis and treatment planning, yet remains challenging in Sub-Saharan Africa due to limited MRI infrastructure and heterogeneous acquisition protocols that induce severe domain shift. We propose SegFormer3D-plus, a radiomics-guided transformer architecture designed for robust segmentation under domain variability. Our method combines: (1) histogram matching for intensity harmonization across scanners, (2) radiomic feature extraction with PCA-reduced k-means for domain-aware stratified sampling, (3) a dual-pathway encoder with frequency-aware feature extraction and spatial-channel attention, and (4) composite Dice-Cross-Entropy loss for boundary refinement. Pretrained on BraTS 2023 and fine-tuned on BraTS-Africa data, SegFormer3D-plus demonstrates improved tumor subregion delineation and boundary localization across heterogeneous African clinical scans, highlighting the value of radiomics-guided domain adaptation for resource-limited settings.
