With a higher power, the embryologist can detect small defects in the sperm head that will not be visible with standard ICSI.
Although there is no benefit for anyone requiring sperm injection yet, it is recommended for those with recurrent implantation failures, recurrent ICSI failures, or severe teratosperms (abnormal sperm shape).
In essence, it is a selection tool to help embryologists choose the most suitable sperm for ICSI.
If the sperm count or motility is too low, if the ICSI limits the number of sperm available, IMSI may not be a suitable technique for you.