“How does a renal ultrasound work?”

An ultrasound involves using special equipment to bounce sound waves off things in the body, in this case the kidneys. It takes less than 30 minutes, uses a special grease (they call it a jelly) to be able to have the sound waves to go from the part of the machine on the skin into the body, and it has no side effects. One could call this a radar exam, just like the naval destroyer looking for submarines!

Sound waves bouncing off organs

It uses ultrasonic waves which have no ionizing radiation to image the organs (including your kidneys) in your abdomen.

Renal ultrasound uses a high frequency sound probe which generates ultrasonic sound waves. When placed on the surface of the body, these sound waves travel though the tissues differently. The sound is reflected off some tissues while it passes through other tissues. This-sound wave transmission in tissues is tissue dependent and can be used to find disease.The process is the same as a submarine using sonar to find other ships or submarines. The appearance of the kidneys on the ultrasound can help the radiologist determine if there is disease or obstruction of the kidneys. It can also find kidney cysts, stones and tumors. Ultrasound is also useful to evaluate the bladder which is often included in the renal ultrasound exam.
The other advantage is the test is fast, real-time, and does not use ionizing radiation ie X Rays.

I hope this helps with better understanding this test.

Ultrasound uses sonar technology from submarines to create an image of internal organs and structures on the computer screen for the radiologist to interpret. The test involves putting a sticky gel on the skin and placing a transducer (about the size of a fist) on the skin surface. The sonar waves are directed into the body. The test is painless, uses no radiation at all, and gives important information. Good test to look for obstruction and stones within the kidney. Best of luck!

Sound waves are used to image the kidneys, it is very safe.