Have calcified vein in pelvis.radiologist report says unidentified ideology.( also have kidney stones) isn't that a phlebolith? why then have a ct ?

Not sure.: Sometimes a phlebolith can't be differentiated from a distal ureter stone on xray, and a CT is done to make the distinction. Perhaps the calcified vein is a larger vein than the small veins associated with phleboliths, and further evaluation is needed. But I can't be sure based on limited info. Try discussing the need for a ct with your doc.