A method and apparatus are disclosed for improving accuracy of placement
of a cannula during delivery of electrical energy proximate to bodily
tissue, e.g. neural structures. The apparatus optionally includes a
cannula operable to deliver electrical current where a portion of the
cannula is electrically insulated and a portion of the cannula is exposed
and electrically conductive. The cannula further includes a radiopaque
marker to identify a specific portion of the cannula, for example to
differentiate the electrically insulated region from the electrically
exposed region, by allowing it to be more clearly delineated using
fluoroscopy or other radiographic imaging techniques. The radiopaque
marker is optionally tapered in order to reduce the force required to
insert a cannula comprising a radiopaque marker into the patient's body.