Attention Blocks Improve White Matter Hyperintensity Semantic Segmentation using U-Nets

Authors

Keywords:

attention blocks, artificial intelligence, alzheimer's disease, semantic segmentation, white matter hyperintensities

Abstract

White matter hyperintensities (WMHs) are a common finding on magnetic resonance (MR) images in older individuals, appearing as high-signal intensity regions on fluid-attenuated inversion recovery (FLAIR) imaging. People with high WMH volume are at increased risk for dementia and stroke, controlling for vascular risk factors, but WMH burden is not reliably assessed in clinical practice. Manual segmentation of WMHs is accepted as the gold standard (or ground truth), however, it is a laborious and time-consuming method. Newer machine learning (ML)-based approaches are being proposed as alternatives to manual segmentation. Among these approaches, U-Net convolutional neural networks have demonstrated good WMH segmentation performance. However, even state-of-the-art ML models sometimes fail to correctly identify WMHs and their boundaries with sufficient accuracy. Attention blocks have emerged as a potential solution for improving the performance of U-Net models by enhancing the ability of the model to focus on relevant features in the data. We investigated the effectiveness of attention blocks in U-Net models for WMH segmentation compared to three other models (U-Net++, U-Net3+, and a standard U-Net). Attention blocks significantly improved the F-measure score for WMH segmentation (0.811 vs 0.789 for next best model, p=0.04) in a diverse brain imaging dataset. This study demonstrates that attention blocks enhance U-Net models used for WMH identification and classification.

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Author Biographies

Kauê Tartarotti Nepomuceno Duarte, University of Calgary

Kaue TN Duarte holds a B.Sc. degree in SystemAnalysis and Technology from the University ofCampinas in S˜ao Paulo, Brazil (2014). His M.Sc.(2017) in texture analysis of natural images andPh.D. (2021) in Alzheimer’s disease prognosis usingimage retrieval and AI were earned at the sameuniversity. He is currently a Postdoctoral Fellow at University of Calgary in Alberta

Murilo Costa de Barros, University of Campinas

Murilo C Barros holds a bachelor’s degree in Building Construction, defending in his last year the work X-band electromagnetic waves in ceramic blocks at University of Campinas. He holds a M.Sc.
in Information and Communication Systems, in the topic of predicting Tourette Syndrome using traditional machine learning techniques. He is currently a Ph.D. candidate at the University of Campinas on CNN applied to the study of Tourette Syndrome, with an internship at National Taiwan University
(Taiwan).

Abhijot Singh Sidhu, University of Calgary

Abhijot S Sidhu holds a Bachelor of Health Sciences Degree (Honours) from the University of Calgary, with emphasis in Biomedical Science and Nanoscience. He obtained his M.Sc. in Biomedical Engineering by understanding physiological brain changing in healthy normal aging using functional Magnetic Resonance images. He is pursuing a PhD in Biomedical Engineering in Dr. Richard Frayne’s
lab.

David Gobbi, University of Calgary

David G Gobbi is the lead software architect at the Calgary Image Processing and Analysis Centre (CIPAC - University of Calgary). Dr. Gobbi holds a BSc, Physics (Honours) at University of British Columbia, a M.Sc. in Physics at Carleton University, and a Ph.D. in Medical Biophysics at University of Western Ontario. He is also an open-source software advocate and a contributor to the Visualization Toolkit.

Cheryl McCreary, University of Calgary

Cheryl R McCreary has a extensive background in adopting imaging techniques to tissues, animal models and people. Among these techniques, some include imaging of white matter to evaluate myelin in a murine model of multiple sclerosis, and MR imaging biomarkers of neurodegeneration associated with cerebral small vessel disease and aging. Dr. McCreary has been working under Drs. Smith and Frayne as an imaging research scientist and MR research manager, developing novel, non-invasive MRI markers.

Feryal Saad, University of Calgary

Feryal Saad earned her medical school degree in the Damascus university and pursued training in radiology at the University of Henri-Poincare and Nancy University hospitals (France). She is a former director and consultant radiologist at Safita Medical Centre - a polyclinic in radiology, cardiology, and digestive specialties. She worked as a consultant radiologist at the Dammam Central Hospital, and  Dammam Medical Complex Tower in Saudi Arabia  and was also a member of the radiology residency
training program.

Richard Camicioli, University of Alberta

Richard Camicioli worked in engineering and medicinal chemistry prior to obtaining his MD, CM, from  McGill University where he also completed a neurologic residency. He perfomed a fellowship training in geriatric neurology at Oregon Health and Sciences University (1994). Dr. Camicioli joined the University of Alberta as an associate professor (2000) and became full professor (2008). Dr. Camicioli’s research interests include cognitive dysfunction and motor dysfunction, especially gait disorders in aging and dementia.

Eric Smith, University of Calgary

Eric E Smith is Professor of Radiology, Neurology, and Community Health Sciences at the University of Calgary - Canada, and holder of the Katthy Taylor Chair in Vascular Dementia. He is the Medical Director of the Cognitive Neurosciences Clinic and a member of the Calgary Stroke Program. He runs  the Clinical and Research Fellowship program in Cognitive Neurosciences. Dr. Smith graduated from McGill University, trained in Neurology in teaching hospitals of Harvard Medical School, and was  Assistant Professor of Neurology at Harvard University, joining University of Calgary in 2008.

Marco Carvalho, University of Campinas

Marco AG Carvalho holds a B.Sc. in Electrical Engineering (Universidade Federal do Rio Grande do Norte, Brazil, 1994), a M.Sc. in image processing at the School of Electrical and Computer Engineering (University of Campinas, Brazil, 1997) and a Ph.D. degree in image processing at School of Electrical and Computer Engineering (University of Campinas, Brazil, 2004). His main contributions are in areas of image processing, architectural segmentation, and image feature understanding.

Richard Frayne, University of Calgary

Richard Frayne is a tenure Professor at University of Calgary (departments of Radiology and  Clinical Neuroscience), and the Deputy Director of the Hotchkiss Brain Institute (HBI). In addition, Dr. Frayne is an associate member of the Libin Cardiovascular Institute, at the Cumming School of Medicine. He manages the Vascular Imaging Laboratory group. He is a former Centre’s Scientific Director (2010-7). During 2003-13, he was the chair at Canada Research in Image Science, as well as held the Hopewell Professorship in Brain Imaging during 2010-24.

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Published

2025-06-26

How to Cite

Tartarotti Nepomuceno Duarte, K., Costa de Barros, M., Singh Sidhu, A., Gobbi, D., McCreary, C. ., Saad, F. ., Camicioli, R. ., Smith, E., Carvalho, M., & Frayne, R. (2025). Attention Blocks Improve White Matter Hyperintensity Semantic Segmentation using U-Nets. IEEE Latin America Transactions, 23(8), 646–661. Retrieved from https://latamt.ieeer9.org/index.php/transactions/article/view/9615