<prompt> Spider leg sign on IVP suggests:Renal stonePolycystic kidneyHypernephromaHydronephrosis  <response>: Ans. b Polycystic kidneyRef: Radiological and imaging secrets 2nd ed. 79 Polycystic kidney autosomal dominant and recessive forms multiple cysts that deform the pelvi-calyceal system resulting in spider leg sign. MC extra -renal malformation in polycystic kidney disease hepatic cysts MC Cardiac malformation in polycystic kidney disease mitral valve prolapse MC GIT malformation in polycystic kidney disease colonic diverticulosisAlso KnowREMEMBER THESE IMPORTANT RADIOLOGICAL SIGNS IN UROLOGY Spider leg appearance--polycystic kidney Cobra head appearance--ureterocele Flower vase appearance of ureters--horse shoe kidney Sandy patches--schistosomiasis of bladder Soap bubble appearance---hydronephrosis 