On the geometric characteristics of cell membrane using rotationally oscillating drill (Ros-Drill©)

ICSI (intracytoplasmic sperm injection) is a broadly utilized assisted reproductive technology. A number of new versions of the procedure have evolved lately, such as piezo-assisted ICSI technique. An important problem with this technique, however, is that it requires small amounts of mercury to stabilize the pipette tip. A completely different and mercury-free technology, called the "Ros-Drill©" (rotationally oscillating drill) was developed by the group of the authors. It uses microprocessor-controlled rotational oscillations of a spiked micropipette for piercing. One of the key issues is to determine when to start the oscillations. It is based on the cell deformation prior to the membrane piercing. In-situ measurements are needed for this protocol. The contribution of this paper is the utilization of computer vision for these measurements. The triggering logic is correlated to the cell membrane curvature variations along the vision-detected membrane line segment. Such a tool becomes very helpful for automating the Ros-Drill operation.