Papers › Medical Image Segmentation Using Squeeze-and-Expansion Transformers

Medical Image Segmentation Using Squeeze-and-Expansion Transformers

20 May 2021arXiv:2105.09511archive 2025-07-28

Shaohua Li, Xiuchao Sui, Xiangde Luo, Xinxing Xu, Yong liu, Rick Goh

Medical image segmentation is important for computer-aided diagnosis. Good segmentation demands the model to see the big picture and fine details simultaneously, i.e., to learn image features that incorporate large context while keep high spatial resolutions. To approach this goal, the most widely used methods -- U-Net and variants, extract and fuse multi-scale features. However, the fused features still have small "effective receptive fields" with a focus on local image cues, limiting their performance. In this work, we propose Segtran, an alternative segmentation framework based on transformers, which have unlimited "effective receptive fields" even at high feature resolutions. The core of Segtran is a novel Squeeze-and-Expansion transformer: a squeezed attention block regularizes the self attention of transformers, and an expansion block learns diversified representations. Additionally, we propose a new positional encoding scheme for transformers, imposing a continuity inductive bias for images. Experiments were performed on 2D and 3D medical image segmentation tasks: optic disc/cup segmentation in fundus images (REFUGE'20 challenge), polyp segmentation in colonoscopy images, and brain tumor segmentation in MRI scans (BraTS'19 challenge). Compared with representative existing methods, Segtran consistently achieved the highest segmentation accuracy, and exhibited good cross-domain generalization capabilities. The source code of Segtran is released at https://github.com/askerlee/segtran.

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Tasks

Brain Tumor SegmentationDomain GeneralizationImage SegmentationInductive BiasMedical Image SegmentationOptic Cup SegmentationOptic Disc SegmentationSegmentationSemantic SegmentationTumor Segmentation

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Brain Tumor Segmentation BRATS 2019 Segtran (i3d) Avg. 0.817 #1 of 5 Archive leaderboard report
Brain Tumor Segmentation BRATS 2019 Segtran (i3d) TC 0.817 #1 of 5 Archive leaderboard report
Brain Tumor Segmentation BRATS 2019 Extension of nnU-Net Avg. 0.812 #2 of 5 Archive leaderboard report
Brain Tumor Segmentation BRATS 2019 Extension of nnU-Net ET 0.740 #2 of 5 Archive leaderboard report
Brain Tumor Segmentation BRATS 2019 Extension of nnU-Net TC 0.807 #2 of 5 Archive leaderboard report
Brain Tumor Segmentation BRATS 2019 Extension of nnU-Net WT 0.894 #2 of 5 Archive leaderboard report
Brain Tumor Segmentation BRATS 2019 Bag of tricks ET 0.729 #3 of 5 Archive leaderboard report
Brain Tumor Segmentation BRATS 2019 Bag of tricks TC 0.802 #3 of 5 Archive leaderboard report
Brain Tumor Segmentation BRATS 2019 Bag of tricks WT 0.895 #3 of 5 Archive leaderboard report
Optic Cup Segmentation REFUGE Challenge Segtran (EfficientNet-B4) Dice 0.872 #2 of 2 Archive leaderboard report

Ranks are positions in the archive's leaderboards as they stood at the 2025-07-28 snapshot. Results published since then are not among these rows, so a rank here is not a current standing.

Methods

Concatenated Skip ConnectionConvolutionMax PoolingReLUU-Net

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