ICSI has proved to be very useful in couples who have failed to achieve fertilization or had very poor fertilization following standard IVF treatment & in couples where the male partner has abnormal sperm parameters like severe oligospermia (very low count), severe asthenozoospermia (very less motility), severe teratozoospermia (high percentage of abnormal sperms) or a combination of abnormalities like oligoasthenoteratozoospermia (very low count, poor motility, abnormal sperms).
ICSI also can be performed in azoospermic men (where semen sample contains no sperms). In such cases the testis are producing sperms but due to block in the tubules or in the path through which the sperms come out from the testis, the sperms produced in the testis cannot come out.Here the sperms are obtained micro surgically from testis or epidydymis (PESA, TESA, and TESE)*. In few cases when there is severe abnormality in the semen, testicular extraction by microsurgical approach (PESA, TESA & TESE) has given normal sperms.
*PESA- Percutaneous Epididymal Sperm Aspiration
TESA – Trans Epididymal Sperm Aspiration
TESE – Testicular Sperm Extraction
What is TESA / TESE /PESA?
TESA, or testicular sperm aspiration (also known as TESE, or testicular sperm extraction) is one of the surgical sperm harvesting techniques used for retrieving sperm in patients with azoospermia. A number of surgical sperm retrieval or recovery methods have been devised to recover sperm from the male reproductive tract.
In men with obstructive azoospermia,(because of duct blockage or absence of the vas deferens) , sperm are usually recovered from the epididymis. The original technique was devised by a urologist, Dr Sherman Silber, who is a specialist in microsurgery. It is a very simple and easy method to recover sperm from the blocked epidiymis. Since the surgeon can feel the turgid epididymis, swollen with sperm, he will blindly puncture the epididymis using a simple butterfly needle – a technique which was very similar to drawing blood from a blood vessel! This simple technique is called PESA (percutaneous epididymal sperm aspiration), in which the sperm is sucked out from the epididymis by puncturing it with a fine needle.
For patients with obstructive azoopsermia in whom sperm cannot be found in the epididymis, it is always possible to find sperm in the testis. The easiest way to retrieve this is through TESA or testicular sperm aspiration , in which the testicular tissue is sucked out through a fine needle, under local anaesthesia. The testicular tissue is placed in culture media and sent to the lab, where it is processed. The sperm are liberated from within the seminiferous tubules (where they are produced) and are then dissected free from the surrounding testicular tissue.