Type of Service (TOS) Indicator 8: Assistant at Surgery
Surgical services billed with an assistant-at-surgery modifier (80-82, AS,) must be reported with TOS 8. The 8 indicator does not appear on the TOS table because its use is dependent upon the use of the appropriate modifier. (See Pub. 100-04, Medicare Claims Processing Manual, Chapter 12, "Physician/Nonphysician Practitioner," for instructions on when assistant-at-surgery is allowable.)
No CPT/HCPCS codes have this indicator. Read the Special Considerations/Exceptions section for details.