A method for removing a vein includes making an incision through a skin layer of a patient, inserting a surgical instrument through the incision, visualizing the vein through the skin layer using a light source positioned subcutaneously and in proximity of the vein, and cutting the vein using the surgical instrument. The vein can be visualized by directing light from the light source at the vein from underneath the vein or from a side of the vein. A device for illuminating a body structure has a housing with a distal end configured for subcutaneous insertion into a patient's tissue and positioning in proximity of the body structure, a light path supported by the housing and configured for directing light at the body structure, and a fluid line supported by the housing.