The Approach Open is identified by number "0" and occupies the 5th position in the ICD10-PCS procedure code structure.
Below a selection of ICD 10 PCS codes related to 00CN0
Extirpation of Matter from Acoustic Nerve, Open Approach
Extirpation of Matter from Acoustic Nerve, Perc Approach
Extirpation of Matter from Acoust Nrv, Perc Endo Approach