In cases of renal sinus lipomatosis, which finding is not typically observed?

In renal sinus lipomatosis, the primary characteristic finding is the significant accumulation of fat within the renal sinus. This condition often presents with a hyperechoic renal sinus when assessed through imaging techniques like ultrasound. The fat deposits can lead to renal atrophy, which is a shrinkage of the kidney due to the loss of renal parenchyma.

Renal sinus lipomatosis typically does not cause an irregular contour of the kidney. The contour usually remains smooth despite the presence of fat in the renal sinus because the fat does not invade the kidney tissue itself but rather surrounds the renal structures. This smooth contour is crucial for differentiating it from other pathologies, such as tumors or scarring, which may lead to an irregular shape.

The presence of a hyperechoic renal cortex is not a typical finding related to renal sinus lipomatosis either. The cortex may appear normal or may show signs of other underlying renal conditions. Thus, the finding of an irregular renal contour is not typically observed in cases of renal sinus lipomatosis.