The Contrast None is identified by letter "Z" and occupies the 5th position in the ICD10-PCS procedure code structure.
Below a selection of ICD 10 PCS codes related to B306Z
Plain Radiography of R Int Carotid using Oth Contrast
Plain Radiography of Right Internal Carotid Artery
Plain Radiography of R Int Carotid using H Osm Contrast
Plain Radiography of R Int Carotid using L Osm Contrast