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 C8191Z
Planar Nucl Med Imag Bi Lacrml Duct w Oth Radionuclide
Planar Nucl Med Imag of Bi Lacrml Duct using Technetium 99m