Percutaneous epididymal sperm aspiration

Percutaneous epididymal sperm aspiration (PESA) is a technique used to determine sperm counts in the event of a possible blockage of the vas deferens. It is an alternative to microepidydimal sperm aspiration (MESA), and aims to address the technical difficulty and cost of MESA. A small needle is inserted through the skin of the scrotum to collect sperm from the epididymis, where sperm are usually stored after production in the testes.

Source: Wikipedia — Percutaneous epididymal sperm aspiration (CC BY-SA 4.0)