Semantic Cardiac Segmentation in Chest CT Images Using K-Means Clustering and the Mathematical Morphology Method

Beanbonyka Rim1, Sungjin Lee1, Ahyoung Lee2

  • 1Department of Software Convergence, Soonchunhyang University, Asan 31538, Korea.

Insights

This study introduces an unsupervised method for whole-heart segmentation in CT scans, combining K-Means clustering and mathematical morphology. The approach aims to improve efficiency and accuracy in detecting cardiovascular diseases like coronary artery disease (CAD).

Area of Science:

  • Medical Imaging
  • Cardiovascular Imaging
  • Artificial Intelligence in Medicine

Background:

  • Whole cardiac segmentation in chest CT images is crucial for identifying cardiovascular diseases (CVDs) and related conditions like coronary artery disease (CAD).
  • Manual segmentation is labor-intensive, time-consuming, and requires specialized radiologist expertise for accurate ground truth labeling.
  • The scarcity of annotated data and the need for expert annotators present significant challenges for developing automated segmentation methods.

Purpose of the Study:

  • To develop an unsupervised semantic whole-heart segmentation technique for chest CT images.
  • To overcome the limitations of manual annotation and data scarcity in cardiac segmentation.
  • To evaluate the proposed method's performance in segmenting cardiac structures from CT data.

Main Methods:

  • A novel unsupervised semantic whole-heart segmentation approach was developed.
  • The method integrates K-Means clustering as a threshold criterion within a mean-thresholding framework.
  • Mathematical morphology operations were employed to enhance threshold shifting and refine segmentation results.

Main Results:

  • Experiments were conducted on 500 subjects using two data subsets: 56 slices (full heart) and 30 slices (upper heart).
  • The K-Means method yielded an average silhouette score of 0.4130 across both cases.
  • Segmentation of 56 slices achieved an overall accuracy (OA) of 34.90% and mean intersection over union (mIoU) of 41.26%.
  • Segmentation of the first 30 slices demonstrated higher performance with OA of 55.10% and mIoU of 71.46%.

Conclusions:

  • The proposed unsupervised method offers a viable alternative to manual cardiac segmentation in CT images.
  • The technique shows potential for aiding in the detection of cardiovascular abnormalities, particularly in datasets with limited annotations.
  • Performance varied between full and partial heart scans, suggesting further refinement may be needed for comprehensive whole-heart analysis.