3D Morphology Measurement for Blastocyst Evaluation From "All Angles".

Area of Science:

• Biomedical Engineering
• Developmental Biology
• Medical Imaging

Background:

• Accurate 3D morphology measurement of spherical cell aggregates is crucial for biological and medical applications.
• Existing methods like fluorescent labeling induce toxicity and 2D estimations lack precision.
• There is a need for non-invasive, quantitative 3D imaging techniques for clinical use.

Purpose of the Study:

• To develop and validate a quantitative, label-free 3D morphology measurement technique for spherical cell aggregates.
• To enable comprehensive, multi-angle morphological evaluation of blastocysts for in vitro fertilization (IVF).
• To overcome the limitations of current toxic and imprecise methods.

Main Methods:

• A multi-view imaging approach was employed for label-free 3D reconstruction.
• Spherical Rotation Scale Invariant Feature Transform (SR-SIFT) was developed to handle feature distortions in multi-view images.
• U-Net with generalized Dice loss was utilized for accurate segmentation of trophectoderm (TE) and inner cell mass (ICM).

Main Results:

• The developed technique achieved rotation angle errors below 1 degree.
• High segmentation accuracy was demonstrated with Dice scores of 95.6% for TE and 92.3% for ICM.
• Overall measurement error for clinically relevant blastocyst parameters was less than 6.7%.

Conclusions:

• The proposed label-free 3D morphology measurement technique offers a significant advancement over traditional methods.
• This technique provides accurate and comprehensive morphological data for blastocysts, enhancing IVF applications.
• The method's non-invasive nature and high precision make it suitable for clinical evaluation and research.