Neurology & Pain Management Coding Alert

When any of the above procedures are performed in the hospital or using equipment not owned by the treating physician, modifier -26 (Professional component) must be appended to show that the neurologist interpreted the results only.

For example, says Steven Dibert, MD, a neurologist at the Neuroscience and Spine Center in Gastonia, N.C., and a member of the board of directors of the American Society of Neuroimaging and of the American Academy of Neurology/Neuroimaging Section, for a patient with stenosis of an artery in the head, the neurologist may order magnetic resonance angiography (MRA) (e.g., 70544), or magnetic resonance imaging (MRI) (e.g., 70551 or 70553) to view the blood vessels of the head and check where the stroke took place and whether it was embolic (material lodged in the artery caused the stroke) or thrombotic (the artery closed off within the brain itself).

Similarly, cerebrovascular studies (93875, 93880 and 93882) may be used to examine the carotid arteries, while the transcranial Doppler tests (93886 and 93888) are appropriate to examine the intracranial arteries.

Generally, a confirmed stroke diagnosis is not available prior to testing. Therefore, medical justification for testing must be based on the patient's signs and symptoms, says Cindy Parmen, CPC, CPC-H, co-owner of Coding Strategies Inc., a healthcare consulting firm in Dallas, Ga.

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). Individual payers maintain lists of diagnoses that (in their view) support medical necessity for a given procedure. When in doubt, contact the payer prior to billing to be sure that your diagnoses supply ample evidence of medical necessity.

Never use a "rule-out" diagnosis of stroke to justify medical necessity for diagnostic testing: This labels the patient inappropriately as having a stroke when he or she may not have. In addition, payers generally do not recognize rule-out procedures, i.e., screenings. In all cases, ICD-9 codes should accurately represent the patient's condition: Choosing an ICD-9 code based on payment rather than the patient's condition is fraudulent and can result in severe penalties.

Note: For more information on ICD-9 coding for diagnostic tests, see Neurology Coding Alert, May 2002.

Establishing medical necessity is especially important when performing multiple tests. And often the physician will want to confirm the diagnosis with additional testing to obtain as much information as possible about the patient's condition. For instance, a patient suspected of having a stroke arrives at the emergency department and receives a CAT scan (70450, Computerized axial tomography, head or brain; without contrast material). Based on the results of the test, the neurologist suspects a brain-stem stroke. Because the CAT scan alone cannot definitively support a diagnosis of brain-stem stroke, the neurologist orders additional testing, such as an MRI.

To demonstrate necessity for the MRI, the neurologist must document his or her reasons for believing the stroke might have occurred in the brain stem and, therefore, the need for additional testing to arrive at a definitive diagnosis. In addition, the neurologist must provide the insurer with copies of all test results to further demonstrate medical necessity.

In a second example, the neurologist wants to determine the cause of a confirmed stroke to prescribe medication: If bleeding caused the stroke, blood-thinning medications should not be administered because they would increase the bleeding. If the stroke was caused by lack of blood flow, however, blood-thinning medication would be appropriate. Such information can be gathered through multiple tests only, Dibert says, and this should be noted in the documentation.

If carriers deny payment because more than one test was performed, full documentation should be sent with the appeal. For carriers with a history of denying multiple-test claims, Dibert suggests the proactive step of sending a copy of all reports the neurologist read along with the initial claim.

Individual payer policies can vary. For example, some insurers will not cover an MRI and ultrasound on the same artery for the same patient, while others will. And not all payers will reimburse all tests used to diagnose strokes, regardless of the attending ICD-9 codes. For example, some Medicare payers have denied payment for an MRA unless a stroke diagnosis was already confirmed, i.e., the payer does not allow an MRA as a diagnostic too.

To reduce denials and time wasted in unproductive paperwork, neurology practices should check for payer restrictions prior to billing.