Orienting Oocytes using Vibrations for In-Vitro Fertilization Procedures

摘要

Accurate positioning of cells is a fundamental task for many procedures in assisted reproductive technologies (e.g. intracytoplasmic sperm injection or preimplantation genetic diagnosis) to extract or insert materials into and from the cell without causing damage to it. The current method of manual manipulation is based on a trial and error procedure performed by skilled embryologists, where they use two different micropipettes to rotate the cell and immobilize it in the desired orientation. This procedure is time consuming, inconsistent and has a low efficiency. Attempts to automate the process presented in the literature have not yet been implemented in IVF clinics because their high degree of automation requires extensive changes to the current systems used in the clinics. We designed a system that can easily be integrated into standard equipment of IVF clinics and allows automated as well as manual manipulation of cells. The system uses vibrations induced by a surface transducer at the pipette holder to rotate the cell around the pipette tip axis, resulting in 2D motion. To detect if the polar body is in the desired position after a vibration burst, we developed a polar body detection algorithm. We performed simulations and experiments to confirm that vibrations at the natural frequencies of the system cause rotation around the pipette tip axis. Experimental results show that the system is capable of positioning the polar body in plane in less than 5.41 seconds.