The novel approach of using excimer laser in a contrast medium for treating an under-expanded stent in a calcified coronary artery is described. In this first reported case, the laser in a contrast medium was used to treat an under-expanded stent deployed 18 months prior in a calcified non-dilatable coronary artery lesion. The normal laser approach in saline medium flush during lasing to clear any contrast was not effective. The use of concurrent contrast during lasing was effective and successful to help expand the stent with a successful outcome.