Renal Cysts

Renal Cysts

Sonographic differential diagnosis of common renal cystic conditions

Fig 1, Fig 2, Fig 3, Fig 4

Fig 1:  Hydronephrosis  Cross-sectional scan of the abdomen: markedly dilated renal pelvis (*) with calyces (arrow)

Fig 2:  Multicystic kidney  Sagittal scan of the abdomen: multiple cysts varying in size in the kidney

Fig 3:  Hydronephrosis  Coronal scan of the abdomen: bilateral dilated renal pelvis (*) (solid circle = bladder)

Fig 4:  Normal kidney   The kidneys consisting of multiple normal pyramids (arrow), looking like multicystic kidney (* = renal pelvis)

Severe hydronephrosis:

• visible renal parenchyma
• peripheral oval cysts communicating with each other and the renal pelvis
• often ureteral dilatation
• underlying cause in some cases such as bladder outlet obstruction
• abnormalities in the contralateral kidney (10-40%)

Autosomal recessive polycystic kidneys

• bilateral enlarged echogenic kidneys with reniform shape
• oligohydramnios

Multicystic kidney disease

• multiple round non-communicating cysts of variable size
• multiple cysts with grape-like appearance in many cases
• unilateral (77%)
• abnormalities in the contralateral kidney (39%)

Renal cystic dysplasia

• echogenic parenchyma and subcapsular or cortical cyst
• evidence of hydronephrosis in some cases
• evidence of an underlying cause such as bladder outlet obstruction in some cases