Oncology & Hematology Coding Alert

When coding computerized axial tomography (CAT) scans, coders need to be aware of what test the physician ordered so they dont bill for services that were not done. In addition, they should know of any other tests that were administered on the same day that might affect how subsequent scans are coded.

One problem, says Cindy Parman, CPC, CPC-H, principal and co-founder of Coding Strategies in Dallas, Ga., is that doctors orders often do not match the codes on the claim. For example, a practice may include 74150 (computerized axial tomography, abdomen; without contrast material) and 72192 (computerized axial tomography, pelvis; without contrast material) when only the abdomen was ordered. Scanning of the abdomen is generally performed to study the viscera and/or retroperitoneal structures.

Medicare specifically defines abdomen, as the area between the dome of the liver and the inferior aspects of the kidneys only. It does not include structures below the pelvic brim.

With the above definition in mind and Parmans warnings about matching codes to orders, coders should use the scenarios below as a guideline:

Abdomen only. 74150-74170.

Pelvis only. 72192-72194.

Coincidental scan of abdomen and pelvis. The radiologist performing the procedure may scan the wider area intentionally or coincidentally and indicate that both the abdomen and pelvis were scanned, prompting both areas to be accounted for in the coding. If the pelvic scan was coincidental and not included in the physicians orders, only 74150 should be listed.

Intentional scan of abdomen and pelvis. When an abdominal and pelvic CAT scan are ordered and performed on the same date, the procedures should be reported using two different codes: 74150, 74160 or 74170; and 72192, 72193 or 72194.

Intentional scan of abdomen and portion of pelvis. When it is medically necessary to include significant slices (views) of the upper pelvis when performing an abdominal CAT, the service should be billed with the higher-valued abdomen exam codes, 74150-74170, and the lower-valued pelvis exam codes, 72192-72194, with modifier -52 (reduced services), says Jim Hugh, MHA, senior vice president with AMAC, a reimbursement and billing firm based in Atlanta. This coding scenario accounts for both areas, but does not seek full reimbursement for a partial pelvic scan.

Use Specific Diagnosis Codes

Specificity is crucial, Hugh says. His reminder to use the proper diagnosis code is not rudimentary advice, but a bell toll acknowledging how easily a CAT scan be denied because of its absence. Local medical review policies list a host of codes that prove medical necessity. They must be used at their highest level of specificity and submitted as the principal diagnosis, he says. For example, there are 15 diagnosis codes for intestinal and colon cancer. Physicians are often too broad in their description of the disease. Intestinal cancer in the patient record could prompt a coder to use 152.9 (small intestine, unspecified). While accurate, a more specific code might be 152.2 (ileum). Failure to use the more precise code in one instance will not affect payment, Parman says. However, a review of coding history by payers that shows CAT scans for unspecified areas will prompt concern that this expensive procedure is being done unnecessarily. This could lead to audits or denials of future claims that list 152.9.

Medicare also assigns the following general rules regarding CAT scans:

Additional views and/or sequences of the same anatomical site will not be reimbursed separately. These are considered incidental to the CAT scan. This includes a high-resolution CAT on the same day and area as a normal one. Although a high-resolution scan offers a better view than normal scans, it is still considered additional. Practices may be tempted to append modifier -22 (unusual procedural services) to account for the extra work, but it is not sufficient to support the claim.

When a CAT scan without contrast is reported on the same day as one with contrast, use 74170 (without contrast material, followed by contrast material[s] and further sections). Coders sometimes use 74150 (computerized axial tomography, abdomen, without contrast material) to describe a CAT scan where contrast material was used prior to the test. Scans are frequently performed after myelograms and anthograms, which require contrast material. Because the material is already present in the area being imaged, practices should code the scan as performed with contrast. Coders should know if the material was used in previous tests so they can account for it by using 74170.

There should be no separate charge for the injection to administer the contrast agent. The injection is considered part of the CAT scan.

Note: Aside from listing the appropriate and most specific diagnosis code, the medical record should support the medical necessity and frequency of this procedure. Documentation should include the attending/treating physicians order for each test.