An Automatic Measurement Method of Zona Pellucida Thickness Based on Coordinate Transformation

摘要

Zona pellucida thickness (ZPT) is one of the indexes to reflect the quality of oocyte and the developmental potentiality of embryo. In order to avoid the error of manual measurement, the inverted microscope image of oocyte is used to measure the ZPT of oocyte. The automatic measurement of the ZPT is helpful to realize the automatic filtering of oocytes in the artificial assisted reproductive technology (ART) and the nuclear transplantation technique (NTT). In this paper, a method that based on coordinate transformation is used for the detection of inner and outer boundary of the zona pellucida. On the basis, ellipse is adopted to fit the inner and outer boundary lines. By referring to the selection of manual measurement point position and combining the ellipse fitting ellipse equation, the automatic measurement of the ZPT is realized. Experiment of measuring the ZPT of 30 mouse oocytes is carried out, and the results show that the method proposed can measure the ZPT precisely and automatically.