Part B Insider (Multispecialty) Coding Alert

COVERAGE:

Don't Leap Past Basic Exams to Expensive Test

Published on Fri May 23, 2003

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Soon you'll have a new diagnostic tool for arterial problems - but don't overuse it, or you may find your practice under the carriers'l ens.

In an April 15 decision memorandum, CAG-00142N, the Centers for Medicare & Medicaid Services said it had decided to issue a National Coverage Determination expanding coverage for magnetic resonance angiography of the abdomen and pelvis to include imaging the renal and aortoiliac arteries. Before the decision becomes effective, CMS must issue a manual instruction, program memo, ruling or Federal Register notice with specific instructions to carriers and an effective date.

CMS says you should obtain an MRA for patients when:

you wish to avoid using contrast angiography

physician history, examination and standard assessment tools don't provide enough information to manage the patient

obtaining an MRA has a high probability of affecting the patient's management positively.

But CMS adds that you can obtain a contrast angiography after an MRA in the "rare instances" when you feel that both tests are medically necessary.

MRA is a nonintensive application of magnetic resonance imaging, analyzing the amount of energy released from tissues exposed to a strong magnetic field to provide images of normal and diseased blood vessels. It also allows physicians to visualize and quantify the blood flow through those vessels. There are two current MRA techniques: phase contrast and time-of-flight.

Current CMS policy covers MRA to image the renal and aortoiliac arteries only when the patient has an abdominal aortic aneurysm or aortic dissection. But the new decision expands the coverage to include diagnosing renal artery stenosis in patients with secondary hypertension, evaluating patients for occlusion of the aortic bifurcation, and evaluating the proximal vessels as part of the workup for patients with peripheral vascular disease.

But no matter what you use MRA for, you need to perform a complete physical workup on the patient first, including appropriate lab tests, and use "clinical suspicion," CMS warns. You should turn to MRA only after standard investigations haven't borne fruit. And you shouldn't order an MRA for a patient as part of an initial office visit, but only if other tests and exams leave you stumped.

CMS will instruct local carriers to take steps to monitor for possible inappropriate use and overutilization of MRAs under the new policy, and one red flag will be resorting to MRA without exhausting standard approaches first.