Once the drug had taken effect, Das gathered a fold of skin, made a puncture, and reached into the scrotum with a fine pair of forceps. He extracted a white tube: the vas deferens, which sperm travel through from the testes to the penis. In a normal vasectomy, Das would have severed the vas, cauterized and tied up the ends, and tucked it all back inside. But rather than snipping, Das took another syringe, delicately slid the needle lengthwise into the vas, and slowly depressed the plunger, injecting a clear, viscous liquid. He then repeated the steps on the other side of the scrotum.
This liquid doesn't block the path of sperm cells exiting the testicles, but renders them inert as they move past. This substance should be removable, thus returning fertility to the patient. You can watch a video of the procedure at the link. Content warning: scrotum.
Link via DVICE | Photo by Flickr user aesop used under Creative Commons license