Question: How can I differentiate between injection/infusion codes 62280-62282? Specifically, what do the terms "subarachnoid "and "epidural" refer to in these codes? Texas Subscriber Answer: Codes 62280 (Injection/infusion of neurolytic substance [e.g., alcohol, phenol, iced saline solutions], with or without other therapeutic substance; subarachnoid), 62281 (... epidural, cervical or thoracic) and 62282 (... epidural, lumbar, sacral [caudal]) all describe injection or infusion of neurolytic substance. CPT further differentiates among these codes according to depth and location of the injection or infusion. Report 62280 for all injections/infusions the physician provides to the subarachnoid space, regardless of the spinal level. The subarachnoid space describes the area beneath the arachnoid membrane (the middle of the three coverings surrounding the central nervous system), which lies below the dural layer. If the neurologist specifies injection/infusion to the epidural (rather than subarachnoid) space, you must choose between 62281 and 62282, according to spinal location. For injection/infusion to the cervical or thoracic levels, choose 62281. For injection/infusion to the lumbar or sacral (caudal) levels, report 62282. When reporting 62280-62282, you may claim multiple injections by billing multiple units and appending modifier -51 (Multiple procedures) to the second and subsequent units. For instance, if the neurologist provides two epidural injections of a neurolytic substance -- one each at a cervical and lumbar level -- you should report 62282, 62281-51. The physician's documentation must independently support the use of each code, outlining the dose, location and medical necessity for all injections.