**Indications:**  
  
 **Please refer to Article A56747, Billing and Coding: Magnetic Resonance
Angiography, for national coverage provisions.**

**Head and Neck** _ _  
__All of the following criteria must apply in order for Medicare to provide
coverage for MRA of the head and neck:

  * MRA is used to evaluate the carotid arteries, the circle of Willis, the anterior, middle or posterior cerebral arteries, the vertebral or basilar arteries or the venous sinuses; _ _ _ _  
  
____

  * MRA is performed on patients with conditions of the head and neck for which surgery is anticipated and may be found to be appropriate based on the MRA. These conditions include, but are not limited to, tumor, aneurysms, vascular malformations, vascular occlusion or thrombosis. Within this broad category of disorders, medical necessity is the underlying determinant of the need for an MRA in specific diseases. The medical records should clearly justify and demonstrate the existence of medical necessity; and,   
  

  * MRA and CA are not expected to be performed on the same patient for diagnostic purposes prior to the application of anticipated therapy. Only one of these tests will be covered routinely unless the physician can demonstrate the medical need to perform both tests.

MRA is appropriately used to verify the presence of a condition, suspected
because of findings from another test (usually an imaging study). For example,
a patient who presents with a transient ischemic attack (TIA) should not
undergo MRA simply because he might have a lesion which is amenable to
surgery. However, if that patient has a carotid bruit and is found by Doppler
study to have carotid stenosis, an MRA may be appropriate to evaluate the
stenotic section of artery for surgical intervention. Please note that the
anticipated surgery may be a percutaneous procedure such as carotid
angioplasty with stent insertion.  
  
Another patient may present with a headache; it is not appropriate to proceed
directly to MRA to rule out the possibility of an intracranial aneurysm.
However, if that patient was found to have a clinically significant amount of
blood in the cerebrospinal fluid, or the patient demonstrated signs and
symptoms strongly suggesting an unruptured intracranial aneurysm, an MRA (or
cerebral angiogram) may be appropriate. An MRA is not considered medically
necessary for screening asymptomatic patients for intracranial aneurysms.  
  
Please note that the anticipated surgery may be a percutaneous procedure such
as carotid angioplasty with stent insertion.

**Peripheral Arteries of Lower Extremities**

  * Both MRA and CA may be useful in some cases, such as: _ _  
__A patient has had CA and this test was unable to identify a viable run-off
vessel for bypass. When exploratory surgery is not believed to be a reasonable
medical course of action for this patient, MRA may be performed to identify
the viable runoff vessel; or,

  * A patient has had MRA, but the results are inconclusive.

_  
_**Abdomen and Pelvis** _  
_  
An MRA of the abdomen for evaluation of possible renal artery stenosis would
not be considered medically necessary without some evidence consistent with
renovascular hypertension. Such evidence might include:

  * a history of early or late onset of hypertension, hypertension refractory to medication, or worsening renal function;
  * the presence of a renal artery bruit;
  * laboratory tests (elevated serum renins, increasing creatinine); or
  * other radiologic tests (ultrasound, captopril scintigraphy, or other imaging showing small kidney or unequal kidney sizes).

_ _