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November 13, 2024

Kidney Anatomy: the Basics

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Kidney Anatomy: the Basics

Our kidneys are responsible for the filtration of our blood in order to remove excess water and waste in the form of urine. They can be found on either side of our spines in what is known as the retroperitoneal space, which is between our posterior abdominal wall and parietal peritoneum–in other words, our mid-to-lower backs. Our fist-sized kidneys are protected by our ribs, as well as layers of fat and muscle. And when we’re at rest, our kidneys get about 25 percent of our cardiac output.

The inside of the kidney has an outer section known as the renal cortex, as well as an inner section called the medulla; the renal pyramids, which aid in moving urine along the excretory process, are contained within the medulla. The renal papillae are bundled collection ducts used to move urine made in the nephrons to the calyces, an area they pass on their way to being excreted in the form of urine. They kidneys also have extensions made up of connective tissue–known as renal columns–that move downward from the cortex and through the medulla, sectioning off the medulla, renal pyramids, and renal papillae. The renal columns also serve an additional purpose: they split the kidneys up into 6-8 distinct lobes and give the vessels entering and exiting the kidney cortex a supportive framework. Together, the renal columns and pyramids make up kidney lobes.

The Ezra MRI scan could screen your kidneys and the accompanying adrenal glands for cancer and other anomalies. You can learn more about our screening packages here.