Automated Quantification of Cerebral Microbleeds in SWI: Association with Vascular Risk Factors, White Matter

Ji Su Ko1, Yangsean Choi2, Eun Seon Jeong1

  • 1From the Department of Radiology and Research Institute of Radiology (J.S.K., Y.C., E.S.J., J.E.P., H.S.K.), University of Ulsan College of Medicine, Asan Medical Centre, Seoul, Republic of Korea.

Abstract

Insights

Deep learning models accurately segmented cerebral microbleeds (CMB), revealing associations between CMB, white matter hyperintensities (WMH), and cognitive decline. Increased WMH and CMB numbers correlate with reduced cognitive function.

Area of Science:

  • Neuroimaging
  • Artificial Intelligence in Medicine
  • Neurology

Background:

  • Cerebral microbleeds (CMB) are linked to cognitive impairment.
  • Accurate quantification of CMB is crucial for understanding neurological conditions.

Purpose of the Study:

  • To develop and validate a deep learning (DL) model for segmenting CMB on SWI.
  • To investigate associations between CMB, cognitive function, and vascular risk factors.

Main Methods:

  • A DL model (nnU-Net) was trained and validated on internal and external datasets.
  • Linear regression analyzed relationships between CMB, cognitive scores (MMSE), white matter hyperintensities (WMH), and vascular risk factors.

Main Results:

  • The DL model achieved robust segmentation performance (Dice score 0.73) internally, with modest external validation (Dice score 0.46).
  • Older age, hypertension, and WMH burden were associated with increased CMB.
  • WMH burden and CMB numbers correlated with decreased cognitive function (MMSE).

Conclusions:

  • Deep learning models demonstrate effective CMB segmentation.
  • CMB and WMH burden are significantly associated with cognitive impairment.

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