Male infertility evaluation involves a thorough history, clinical examination, lab tests and a few scans. Men are often perplexed when they are asked to undergo scans and are quite skeptical about getting a Trans Rectal Ultrasound (TRUS) done. A TRUS may be associated with a little discomfort as it has to be performed through the motion passage (rectum). Hence it becomes necessary to talk about it here.
Azoospermia is defined as complete absence of sperm in the ejaculate. It can be either obstructive or nonobstructive. Obstruction could be complete when it is localized to the structures around the testis, like epididymis and the testis itself. In a small percentage it could be distal with a block in the ducts transporting the semen (ejaculatory ducts). TRUS helps in identifying blocks in the ejaculatory ducts and also tells us about the nature of the distal ejaculatory system which includes the ampullae of vas deferens , seminal vesicles, ejaculatory ducts and the prostate.
Who should undergo TRUS?
A typical candidate with Obstructive Azoospermia can have a distal total block with a very low volume ejaculate , absence of fructose and absence of sperm. Patients with partial block are also candidates for TRUS. These patients may have reduced sperm counts and borderline fructose levels. The procedure itself is pretty simple and does not require anaesthesia. It is invariably done with the patient lying on the side with little or no discomfort. Anatomy of the distal ejaculatory system is captured in a purposeful manner.
Advantages of TRUS
- Anomalies of the distal ejaculatory ducts can be picked up with accuracy
- Cost effective
- Easy top perform and convenient
- Minimal risk
- Complications are less
Appilcations of TRUS
Not only is TRUS used in the diagnosis of Obstructive Azoospermia, it can also be used to help in treatment. Under TRRUS guidance, midline cysts causing blocks/obstruction can be decompressed. A permanent solution would however be a resection (TURED) and TRUS could be used to monitor this. Seminal vesicles can be aspirated for sperm.