KUB & radio opaque calculas
Standard plain film of abdomen is in supine position. (when suspected of gas under diaphragm or to see air fluid level adv. Standing abdomen or erect film) Psoas outline is clearely visible. Kidney shadow is obscured by overlying colon. Look for any radio opaque shadow in the region of kidney, ureters or bladder. Faecolith should not be mistaken for renal or ureteric calculas.