The Qualifier None is identified by letter "Z" and occupies the 6th position in the ICD10-PCS procedure code structure.
Below a selection of ICD 10 PCS codes related to B502YZ
Plain Radiography of Intracran Sinus using L Osm Contrast
Plain Radiography of Intracran Sinus using H Osm Contrast
Plain Radiography of Intracranial Sinuses using Oth Contrast