Mississippi Subscriber
Answer: The ASA Crosswalk lists several crossover codes for 64680, including 01991 (Anesthesia for diagnostic or therapeutic nerve blocks and injections [when block or injection is performed by a different provider]; other than the prone position) and 01992 (Anesthesia for diagnostic or therapeutic nerve blocks and injections [when block or injection is performed by a different provider]; prone position).
Other alternative codes include 00300 (Anesthesia for all procedures on the integumentary system, muscles and nerves of head, neck, and posterior trunk, not otherwise specified) and 00400 (Anesthesia for procedures on the integumentary system on the extremities, anterior trunk and perineum; not otherwise specified).
But be sure the procedure involved the integumentary system before reporting 00300 or 00400, because this is rare for procedures involving nerve destruction. In the situation you describe, one physician is performing the neurolytic injection and the other is providing anesthesia. If the same physician does both, conscious sedation, not anesthesia, is performed.