Renal Ultrasound

Background

Renal ultrasound is a noninvasive diagnostic test that uses high-frequency sound waves to create real-time images of the kidneys. The images are two-dimensional pictures of the kidneys that evaluate their size, shape, architecture, and location. It can also be used to evaluate the blood flow to and from the kidneys. The underlying complex architecture of the kidneys is represented by the variety of echotextures seen within the kidney parenchyma. The array of echotextures are a direct representation of the density of the tissues present within the kidneys. For example, the renal pyramids are darker than the renal cortex. A change in the renal architecture may represent a congenital deformity or a disease process. Fig. 50.1 is an example of a renal ultrasound of a depth in the body and distance from the ultrasound probe. The more superficial structures are displayed toward the top of the screen, whereas the deeper structures are displayed near the bottom of the screen.