"We had been using the CPT Codes 74150 (Computed tomography, abdomen; without contrast material) and 76375 (Coronal, sagittal, multiplanar, oblique, 3-dimensional and/or holographic reconstruction of computed tomography, magnetic resonance imaging, or other tomographic modality) for these procedures ever since Oct. 18, 2002, when CPT Assistant recommended them," Fulkerson says. Now, however, you should report the T codes instead of the Category I codes. Rule: "If a Category III code exists for your procedure, you must use it," says Marvel Hammer, RN, CPC, CHCO, owner of MJH Consulting in Denver. You may not revert back to the prior code unless a private payer instructs you to do so. T codes represent emerging technology, services and procedures. They may evolve into Category I codes, depending on usage, clinical efficacy, and federal Food and Drug Administration approval. After five years, the codes either graduate to Category I or receive approval to continue their status as information collectors in Category III. Remember: T codes do not carry a relative value unit (RVU) rating. Individual payers (rather than the yearly fee schedule) determine reimbursement (and coverage) for these procedures. Nonetheless, correct coding principles dictate that you report the procedure. For a complete list of new Category III codes effective July 1, visit www.ama-assn.org/ama/pub/article/3885-4897.html.