Measuring the Refractive Index of Oocytes by Means of an Optical Microsystem - A Non Invasive Technique to Estimate the Evolution of Oocytes Maturity

In this paper, we present an optical microsystem used to measure the refractive index of oocytes. The technique relies on oocytes refraction properties and on the optical coupling between optical fibers. A theoretical model of the system is established by means of matrix optics. A numerical fitting allows calculating the refractive index of the oocytes. In a first time we considered the oocytes like homogeneous spheres. In a second time, we considered that the oocytes consist of a shell (the zona pellucida) and a core (the cell). Experimental results showed that the refractive index of the oocytes increases during the maturation process. In this position paper, we also discuss the temporal evolution of the oocytes maturity and we point out that the maturation should not only be estimated visually but in a more continuous manner. The device we propose could be a solution for such non invasive measurements.