<prompt> Spider leg appearance is found in :Polycystic kidneyPyelonephritisHydronephrosisRenal aery stenosis  <response>: A i.e. Ploycystic Kidney Chronic hydronephrosis is most common cause of abdominal mass in first 6 months of life.Q On IVP it shows: - Early Rim SignQ thin band of radiodensity surrounding clyces - Delayed Opacification dialation collecting system Polycystic or Congenital cystic kidney presents with abdominal mass, loin pain, heamaturia, infection, hypeension uremia; but usually not before age of 30 years. On excretory urography it has BL spiders leg apearanceQ. Decapping surgery Rovsings operation is rarely indicated, as it only relives pain no prognostic change Radiological Feature Disease Rim Cresent SignQ d t ureteric Hydronephrosis pelvic dialatation lit coex compression Soap Bubble appearanceQ Hydronephrosis Flower vase appearance of ureterQ Horse shoe kidney Drooping flower appearanceQ Ectopic ureter Cobra Adder head appearanceQ Ureterocoel Thimble bladderQ Tubercular cystic chronic Sandy patchesQ Schistosomiasis of bladder Fish hook bladderQ BPH BL Spider leg appearanceQ Polycystic kidney Swiss-cheese nephrogram Sub burst nephrogram Egg in cup appearance, ring Papillary necrosis shadows ring sign, lobster claw analgesic sign or calyceal horns and diminished density of contrast in nephrogramQ nephropathy Tree barking or Corduroy Squamous appearance in IVU or RGU i.e. metaplasia of multiple linear radiolucencies in ureter lit mucosal ureter thickening 