Localized thinning of the right renal parenchyma on CT examination is generally considered to be induced by congenital or acquired factors. 1. Congenital factors: clinically more common renal pelvic and ureteral junction stenosis, because of congenital lesions, will cause the ureter and renal pelvic junction elasticity deterioration, with the age will lead to aggravation of stenosis, resulting in increased hydronephrosis, affecting renal function, and triggering thinning of the renal cortex. 2. Acquired factors: Acquired obstruction, such as inflammation or ischemia-induced scarring, can lead to ureteral stenosis, causing stones and tumors in the renal pelvis and ureter, inducing hydronephrosis, and also causing renal cortex thinning. It is suggested that patients should go to regular hospitals for examination when necessary, and according to the results, standardized treatment under the guidance of specialists.