Coding Q&A

Coding for diagnostic tests and screenings


Coding for Diagnostic Tests and Screenings


Q. I recently heard that there are different Medicare rules for coding diagnostic tests that vary from what you do for office coding. Could you please explain that?

A. Medicare clarified some time ago that when a test is ordered and the physician confirms the diagnosis based on the results of the diagnostic test, that diagnosis should be coded. Signs and symptoms that prompted ordering the test in the first place may be coded as additional diagnoses.

Medicare has issued the following guidelines:

► If the test confirms a diagnosis, code the diagnosis.

► If the test results do not yield a diagnosis, or are normal, then the signs/symptoms that prompted ordering/performing the test should be coded.

► If the physician performs a test for a referral sent in with a "rule out" or uncertain diagnosis, then again the signs/symptoms that prompted ordering or performing the test should be reported.

Keep in mind that you must document your rationale for the medical necessity of performing the test if it is not readily apparent in the chart documentation. When dealing with ophthalmology audits, it is best to assume the auditor is not very familiar with ophthalmology, and in particular retina. Document needs for diagnostic tests and add brief medical rationale.

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Example 1: A patient is referred for possible cystoid macular edema. Fluorescein angiography is performed and a diagnosis of cystoid macular edema is made. Therefore code the findings, macular edema. [Abnormal test = code findings]

Example 2: A patient is referred for possible macular edema and fluorescein angiography is performed. No evidence of macular edema is present. Since the test is normal, code what prompted ordering of the test, such as blurry vision (368.8). [Normal test = code signs prompting ordering of test]

Example 3: A patient is referred to a retina specialist by a comprehensive ophthalmologist with a working diagnosis of macular edema in the right eye. Fluorescein angiography is performed and does not confirm the presence of cystoid macular edema. An appropriate diagnosis for the test would be: 368.8 Blurred vision. [Normal test = code signs or symptoms prompting ordering of test]

Medicare issues Local Coverage Determinations for educating providers on the various diagnostic tests and a list of covered diagnoses is part of the document. If the diagnosis you code is not on the list for that given test, then the claim will be rejected. Remember the long struggle to get the various retinal diagnoses listed on the policies for SCODI when OCT first came out.

Tests performed for screening purposes are not considered by Medicare as a covered service and should not be submitted for payment.

Q. Our practice is interested in offering OCT screenings on days when our retina physician is in surgery. Any help or advice would be appreciated.

A. If the "screening" is being done as part of a goodwill campaign by the practice, and no claims will be submitted, then the practice may offer them provided they meet all the legal requirements. It is recommended counsel by a healthcare attorney be used prior to initiating this.

No type of inducement should be offered nor should a fee be charged. If you plan on dilating the pupils, once again obtain legal advice before proceeding. OCT screenings must be performed under the rules of "general supervision," meaning that the procedure is furnished under the physician's overall direction and control, but the physician's presence is not required during the performance of the procedure. The training of the nonphysician personnel who actually perform the diagnostic procedure and the maintenance of the necessary equipment and supplies are the continuing responsibility of the physician. RP

CPT codes copyright 2006 American Medical Association.