Last reviewed on: October 15, 2022
Renal scans are safe and widely available tests that provide information about the morphology and function of the kidneys utilizing radiopharmaceuticals with high renal clearance (Sfakianakis, 1988). This information supplements that obtained by other imaging methods (Ultrasound, CT, MRI) (Boubaker 2006, De Palma 2014), and its special value is to measure relative renal function. Anatomical abnormalities causing renal vascular or urinary tract malfunction can be clarified. This potential can be enhanced with drugs that stress renal functional capability. Radiopharmaceuticals used to perform renal scans can be divided into three major categories: filtered by the glomerulus, secreted by the tubules, and retained in the tubules via receptor-mediated endocytosis.
Functional agents (filtered by the glomerulus and/or secreted by the tubules) are used in the dynamic renal scan (renography), and morphological agents (retained in the tubules) are used in the static (cortical) renal scan.
Dynamic scans elucidate the uptake and drainage of the radiopharmaceutical and allow the generation of time-activity curves by selection of regions of interest, while static scans image the functional renal tissue and provide useful morphologic information.
An understanding of the principles of the test, its limitations and the sources of error is essential to the interpretation of the results and effective use of renal scintigraphy.