The Isotope 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 D9YDFZ
Hyperthermia of Nasopharynx
Contact Radiation of Nasopharynx
Intraoperative Radiation Therapy (IORT) of Nasopharynx
Plaque Radiation of Nasopharynx