ICSI is an acronym for Intracytoplasmic Sperm Injection and is a technique for egg fertilization. A sperm is inserted directly into the egg.
This technique is applied in cases of male factor infertility, with poor sperm numbers and reduced mobility. It is also preferred in cases of poor egg quality and occasionally in cases of sperm donors.
The technique is done with the help of a microscope and controls. A pipette keeps the egg stable by applying negative pressure. On the opposite side of the cell, a micropipette, in the shape of a needle, pierces the egg and leaves the sperm it contains in the cytoplasm.
IMSI is a fertilization technique where the sperm are selected for the ICSI technique using a larger magnification. While with the classic ICSI the magnification is 400 whereas whith IMSI it is 6600.
Having this best image, the sperm with the best morphology are selected.