Microsurgical Epididymal Sperm Aspiration
Microsurgical epidiymal sperm aspiration is easier remembered by its acronym: MESA. MESA is the best method for retrieving sperm from men who have a blockage of the reproductive tract. Such blockages may occur after a vasectomy or as the result of a congenital defect in which there is no vas deferens at birth. The epidiymis is an organ located above the testicles in which the sperm are stored.
A half inch incision is made in the skin of the scrotum so that the epididymis can be located. A special microscope is then used to view the tiny "tubules" of the epididymis where the sperm is contained. The tubule is dilated and the fluid it contains is gathered and examined to determine the presence and health of the sperm it may contain.
The fluid is then brought to the IVF lab where it will be processed for use. Sperm not used right away will be frozen. If the fluid is found not to contain any live sperm, another sample will be taken from a different section of the epididymis. The search and examination is continued until enough live sperm are gathered for immediate use and for storage.
The extra sperm are needed because it is usual for a couple to undergo many IVF or ICSI procedures. It's best then, to take more sperm than is needed for immediate use to prevent the patient from having to go through the MESA procedure every time more sperm are needed. It's also true that many couples will want more than one child and the sperm retrieved through this procedure maintains its integrity quite well in comparison with other, similar retrieval techniques.
MESA not only means that stored sperm will be of impeccable quality, it's also the safest retrieval method available. The procedure has the lowest rate of complications, swelling, or pain. Because the operating field is viewed through a microscope, the testicle itself is spared entry. Should there be any bleeding, it can be brought to a stop with alacrity.
Patient recovery time from MESA is 24 hours after which the patient can return to his work and regular daily activities. The procedure can be done in a doctor's office as long as it is equipped with an operating microscope and microsurgical instruments. A spermatic cord block acts as a local anesthetic to numb the area. Patients also receive sedation to make them more comfortable.
MESA is still not very widely available and tends to be offered only at centers which specialize in treating male factor infertility. This is due to the specialized nature of the equipment and the need for a trained infertility microsurgeon. MESA is considered more cost-effective than the other sperm retrieval techniques because it only needs to be performed once, while the other techniques may need to be performed numerous times.