Intracytoplasmic morphologically selected sperm injection (IMSI) is a sperm selection method used in intracytoplasmic sperm injection (ICSI). The technique involves using a microscope to view images of the sperm under very high magnification to select the sperm to inject into an oocyte.
There have been several randomised controlled trials (RCTs) within the last decade showing very little evidence of benefit of using IMSI, and the evidence is also of low quality. The research that has been carried out does not support the use of IMSI over standard ICSI. One small study found that IMSI had improved pregnancy outcomes in older patients, however this study was carried out with a small number of participants and the link, between IMSI and older oocytes is not fully understood. In IMSI sperm selection process precedes the micro-injection.
An advanced modification of the ICSI technique, IMSI treatment examines the sperm samples under a microscope that is almost 6000x more persuasive to evaluate their "morphology" more effectively. The embryologist can see relatively small deformities in the sperm head that aren't noticeable with standard ICSI at a higher magnification. Although it is yet to be proved to be of benefit for all involving sperm injection, it is recommended in those with a history of repetitive implantation failures, repeated ICSI failures or severe teratozoospermia (abnormal sperm shape).
An inverted light microscope, achieves a magnification of up to ×6600 and allows the real-time assessment of morphological characteristics of motile spermatozoa. The selection of spermatozoa is often performed on glass- bottomed dishes to achieve the best optical quality, whereas microinjections are performed on a separate plastic dish. Semen sample preparation requires a specific procedure that varies according to the semen quality. The selection phase requires a suspension of spermatozoa prepared from discontinuous density gradient centrifugation. The pellet is then suspended in SPERM culture medium to obtain a final concentration of motile sperms of approximately four million spermatozoa per ml. The sperm suspension is then deposited in polyvinylpyrrolidone microdroplets covered with mineral oil. The morphologically normal spermatozoon is then aspirated with an ICSI injection pipette and subsequently added to a microdroplet of medium on the plastic Petri dish. The droplet is then covered with mineral oil and the injection is finally performed. Because the detailed analysis of each sperm takes longer, the IMSI procedure lasts roughly twice as long as regular ICSI.
Intracytoplasmic Morphologically Selected Sperm Injection (IMSI) is a sperm infusion (ICSI) of an exceptionally chosen single sperm straightforwardly into the full-grown egg. IMSI is a new and moderately unstudied strategy. Sperm have formed heads and frequently have vacuoles (holes) and it is accepted that these strange sperm are less inclined to convey typical hereditary elements. IMSI Treatment utilizes high force amplification to distinguish these irregularities of sperm, thus selecting the most typical looking sperm. Since sperm are so minuscule contrasted with the egg, exceptional high force amplification is required. With the advanced procedure of IMSI Treatment, high-quality sperms are detected for final fertilization.