The Approach External is identified by letter "X" and occupies the 5th position in the ICD10-PCS procedure code structure.
Below a selection of ICD 10 PCS codes related to 0HNXX
Release Left Nipple, Via Natural or Artificial Opening
Release Left Nipple, Open Approach
Release Left Nipple, Percutaneous Approach
Release Left Nipple, External Approach
Release Left Nipple, Endo