https://www.selleckchem.com/pr....oducts/pyrvinium.htm
The claw sign is advocated as a discriminant of renal versus non-renal origin of tumours. The accuracy of the claw sign on magnetic resonance imaging (MRI) is unknown and is potentially hindered by the inferior spatial resolution and the larger tumour sizes at presentation in developing countries. To define and evaluate the claw sign in differentiating renal from non-renal retroperitoneal masses in children undergoing MRI. A definition of the claw sign was proposed. Magnetic resonance imaging studies, clinical and laboratory records o