Neurology & Pain Management Coding Alert

Here's when you can bill separately for duplex scan interps Just because your neurologist orders and interprets a duplex scan for a stroke victim doesn't mean you can bill separately for the service. You can consider the test interpretation as a part of any E/M service the neurologists provides, however. An Arkansas reader asks: "Why are we getting so many denials for 93880? Our physicians only read the results of the test, and therefore we attach modifier -26. In most cases, we use a diagnosis of 433.10."
 
According to our experts, the reader is doing at least two things correctly but may be overlooking a third problem: The neurologist may not be able to bill for the test interpretation at all.  Begin With a Solid Diagnosis If you're going to bill for duplex scan interpretation (or any diagnostic or therapeutic service), your claim must include a payer-approved diagnosis to show medical necessity.
 
Codes 93880 (Duplex scan of extracranial arteries; complete bilateral study) and 93882 (... unilateral or limited study) represent the current "gold standard" for diagnostic cerebrovascular ultrasound, which neurologist may use to examine the carotid arteries and verify a diagnosis of stroke.
 
Neurologists will order 93882 most frequently for a follow-up study rather than as an initial diagnostic test. Typically, an ordering physician will request a bilateral study (93880) for a full study of both carotid arteries. After locating and treating the suspected blockage, the physician may order a limited study for a specific site to determine the success of the treatment.
 
Rely on signs and symptoms: Because the neurologist generally will not have confirmed a stroke diagnosis (434.91, Cerebral artery occlusion, unspecified; with cerebral infarction) prior to testing, you must rely on signs and symptoms diagnoses to support medical necessity for diagnostic scans, says Marvel J. Hammer, RN, CPC, CHCO, owner of MJH Consulting, a healthcare reimbursement consulting firm in Denver.
 
Typical signs and symptoms for stoke victims include cerebral atherosclerosis (437.0), paralysis (344.9), hemiplegia (342.91), loss of vision (369.9), occlusion of arteries (434.9x or 433.1x, as applicable), transient cerebral ischemia (435.9), aneurysms (442.9), stenosis (447.1), speech problems (784.5), and injury to blood vessels (904.9), among others.
 
What NOT to do: Never use a "rule-out" diagnosis of stroke to justify medical necessity for diagnostic testing, Hammer says. This labels the patient inappropriately as having a stroke when he may not have.
 
However, if testing confirms a stroke diagnosis, you may apply that diagnosis and use the signs and symptoms as secondary diagnoses. Our Arkansas subscriber checks out here: She has chosen a diagnosis of 433.10 (Occlusion and stenosis of precerebral arteries; carotid artery; without mention of cerebral infarction), which most insurers, including most local Medicare payers, accept for 93880. Append Modifier -26 If [...]