Normal Adult Kidney. The renal cortex (short arrow) is equal in echogenicity to the liver parenchyma (l). The renal pyramids (long arrow) are slightly hypoechoic compared to the renal cortex. The septal cortex extends between the medullary pyramids. The central renal sinus (s) is invested with echogenic fat. The contour of the kidney is sharply defined by fat in the perirenal space. The length of the kidney is measured between cursors (+).

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