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 CF161Z
Planar Nucl Med Imag Liver & Spleen w Oth Radionuclide
Planar Nucl Med Imag of Liver & Spleen using Technetium 99m