A scrotal ultrasound, also known as a testicular ultrasound, is a male-specific ultrasound sub-type that focus on the scrotum, the skin sac that holds the testicles in place. 

The testicular ultrasound uses high-frequency sound waves to capture detailed images of the scrotum’s inner structure, such as the spermatic cord, epididymis, and testicles. 

The scrotal ultrasound is a painless and non-invasive diagnostic test that works on the principles of sonar, the same technology used by navies to detect planes and ships. 

However, if your testicles are tender or inflamed, the procedure might be a bit painful. In such a case, inform the ultrasound technician before the procedure.