Which procedure treats kidney stones with pulsating sound waves?

• A. Lithotripsy
• B. Cystoscopy
• C. Nephrectomy
• D. Ureteroscopy

Answer: (A)

Pulsating sound waves are used to break kidney stones into smaller pieces that can pass more easily in the urine. This approach, known as lithotripsy (specifically extracorporeal shock wave lithotripsy), uses a machine outside the body to generate high-energy acoustic pulses that are focused onto the stone. The energy causes the stone to fracture into tiny fragments, which patients then pass spontaneously or with minimal assistance.

This differs from endoscopic or surgical options. Cystoscopy is an internal examination of the bladder and can be used to retrieve stones with instruments, but it does not use external shock waves to fragment them. Nephrectomy removes the kidney, not a fragmentation method. Ureteroscopy involves threading a scope into the ureter to directly visualize and often break or retrieve stones with laser or baskets, not with external shock waves.