Per AMA CPT Assistant it is unlisted.
AMA CPT Asisstant December 2018
Surgery: Nervous System
Question: What are some examples of paravertebral blocks (PVB) captured in CPT codes 64461-64463? It was assumed that erector spinae is one example, but an FAQ in the January 2018 issue of the CPT® Assistant newsletter referred to code 64999 instead. However, according to some physicians, the erector spinae is actually a paravertebral structure that is commonly addressed, injected, or treated, when performing postoperative pain blocks or managing postoperative pain.
Answer: A PVB targets the sympathetic chain of nerves and somatic nerves (intercostal and spinal nerves and their branches), which may be utilized for dermatomal coverage from T2 (thoracic level 2) to L1 (lumbar level 1). In contrast, the erector spinae is a group of muscles and tendons extending the length, and on both sides, of the spine. It is not a separately identified spinal nerve or branch. Therefore, code 64999, Unlisted procedure, nervous system, would be the most appropriate code to report for this type of procedure, as stated in the January 2018 issue of the CPT® Assistant.
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AMA CPT Assistant January 2018
Surgery: Nervous System Question:
What is the appropriate code to report an erector spinae plane (ESP) block for postoperative pain in which the needle is inserted at the T5 transverse process under ultrasound guidance? A local anesthetic test dose was delivered and a catheter was threaded. This particular ESP block was for post-thoracotomy chest wall pain.
Answer: There is no specific CPT code that describes this service; therefore, code 64999, Unlisted procedure, nervous system, should be reported for the ESP block. When reporting an unlisted code to describe a procedure or service, it will be necessary to submit supporting documentation (eg, procedure report) along with the claim to provide an adequate description of the nature, extent, and need for the procedure; and the time, effort, and equipment necessary to provide the service.