Answer:
A modifier provides the means by which the reporting physician can indicate that a service or procedure that has been performed has been altered by some circumstance but not changed in its definition or code. It obviates the need for a separate procedure listing that may describe the modifying circumstance.
Modifiers may be used to report that:
- a procedure has both a professional and technical component
- a procedure was performed by more than one physician
- a procedure has been increased or reduced
- only part of a procedure was performed
- an adjunctive procedure was performed
- a bilateral procedure was performed
- a procedure was performed more than once
- unusual events occurred
Some examples of modifiers pertinent to plastic surgery:
- 20 Microsurgery
- 47 Anesthesia by surgeon
- 50 Bilateral procedure
- 51 Multiple procedures
- 62 Two surgeons
- 80 Assistant surgeon
- others, see Appendix A of CPT book