Compliance with the provisions in this policy may be monitored and addressed
through post payment data analysis and subsequent medical review audits.

**History/Background and/or General Information**

Intraoperative neurophysiological testing may be used to identify/prevent
complications during surgery on the nervous system, its blood supply, or
adjacent tissue. Monitoring can identify new neurologic impairment, identify
or separate nervous system structures (e.g., around or in a tumor) and can
demonstrate which tracts or nerves are still functional. Intraoperative
neurophysiological testing may provide relative reassurance to the surgeon
that no identifiable complication has been detected up to a certain point,
allowing the surgeon to proceed further and provide a more thorough or careful
surgical intervention than would have been provided in the absence of
monitoring. Monitoring, if used to assess sensory or motor pathways, should
assess the appropriate sensory or motor pathways. Incorrect pathway monitoring
could miss detection of neural compromise and has been shown to have resulted
in adverse outcomes.

Some high-risk patients may be candidates for a surgical procedure only if
monitoring is available.

**Covered Indications**

Based on information in the scientific literature, intra-operative testing may
be considered reasonable and necessary for the following:

  * Surgery of the aortic arch, its branch vessels, or thoracic aorta, including carotid artery surgery, when there is risk of cerebral or spinal cord ischemia
  * Resection of epileptogenic brain tissue or tumor
  * Resection of brain tissue close to the primary motor cortex and requiring brain mapping
  * Protection of cranial nerves:   

    * Resection of tumors involving the cranial nerves
    * Cavernous sinus tumors
    * Microvascular decompression of cranial nerves
    * Skull base surgery in the vicinity of the cranial nerves and surgeries of the foramen magnum
    * Oval or round window graft
  * Endolymphatic shunt for Meniere's disease
  * Vestibular section for vertigo
  * Correction of scoliosis or deformity of spinal cord involving traction of the cord
  * Protection of spinal cord where work is performed in close proximity to cord as in the placement or removal of old hardware or where there have been numerous interventions
  * Spinal instrumentation requiring pedicle screws or distraction
  * Decompressive procedures on the spinal cord or cauda equina carried out for myelopathy or claudication where function of spinal cord or spinal nerves is at risk
  * Spinal cord tumors and spinal fractures (with the risk of cord compression)
  * Neuromas of peripheral nerves of brachial plexus, when there is risk to major sensory or motor nerves
  * Surgery or embolization for intracranial AV malformations
  * Surgery for arteriovenous malformation of spinal cord
  * Embolization of bronchial artery AVMs or tumors
  * Cerebral vascular aneurysms
  * Surgery for intractable movement disorders
  * Arteriography, during which there is a test occlusion of the carotid artery
  * Circulatory arrest with hypothermia (does not include surgeries performed under circulatory bypass [e.g., CABG, ventricular aneurysms])
  * Distal aortic procedures, where there is risk of ischemia to spinal cord
  * Leg lengthening procedures, where there is traction on sciatic nerve or other nerve trunks
  * Basal ganglia movement disorders
  * Surgery as a result of traumatic injury to spinal cord/brain
  * Deep brain stimulation, and
  * Certain thyroid surgeries (see below for additional guidance)

Thyroid Surgery

Intraoperative neurophysiologic monitoring during thyroid surgery is
considered reasonable and necessary if the monitoring service adheres to the
essential standards described above, and the surgical procedure involves the
high-risk total removal of a complete lobe of the thyroid, removal of the
entire gland, or involves re-entry (re-operation) to a prior surgical field
where scar tissue obscures the visual path of the recurrent laryngeal nerve.
The surgeries described here are most appropriately reported as a total
removal of thyroid lobe on one side of the neck, removal of thyroid, removal
of thyroid and surrounding lymph nodes or removal of remaining thyroid tissue.
The contractor reserves the right to remove coverage for monitoring during
thyroid surgery if the literature ultimately does not support this monitoring.

**Limitations**

  1. This test must be ordered by the operating surgeon and the monitoring must be performed by a physician who is other than: 
    * the operating surgeon;
    * the technical/surgical assistant; or
    * the anesthesiologist rendering the anesthesia.  
  

  2. The benefits of intraoperative neurophysiologic testing are attainable under optimal recording and interpreting conditions. The beneficial results of monitoring demonstrated by the 1995 multicenter study of this technique were realized under the following conditions in a hospital setting: 
    * A well trained, experienced technologist was present at the operating site recording and monitoring a single surgical case.
    * A physician who is a trained clinical neurophysiologist (MD/DO) supervised the technologist.
    * The surgical team and the monitoring staff were always in immediate contact.  
  

  3. Due to the nature of these services and the potential for significant morbidity, in procedures requiring intraoperative monitoring, these services are considered reasonable and necessary only when performed in the inpatient and outpatient hospital settings or Ambulatory Surgical Center. Please note, the outpatient settings are only considered reasonable and necessary for intraoperative monitoring of procedures that are not designated as inpatient-only procedures. As the level of anesthesia may significantly impact the ability to interpret intraoperative studies, continuous communication between the anesthesiologist and the monitoring physician is expected when medically indicated.  
  

  4. It is also required that a specifically trained technician, preferably registered with one of the credentialing organizations such as the American Board of Neurophysiologic Monitoring or the American Board of Registration of Electrodiagnostic Technologists will be in continuous attendance in the operating room, recording and monitoring a single surgical case, with either the physical or electronic capacity for real-time communication with the supervising neurologist or other physician trained in neurophysiology.  
  

  5. Intraoperative monitoring is not medically necessary in situations where historical data and current practices reveal no potential for damage to neural integrity during surgery. Monitoring under these circumstances will exceed the patient's medical need.  
  

  6. Due to the potential risk for morbidity with many of the above noted surgeries and the need for explicit and focused attention to both the monitoring and the procedure, it is not reasonable and necessary for the operating surgeon to perform this service. Monitoring may be performed from a remote site, as long as a trained technician (see detail above) will be in continuous attendance in the operating room, with either the physical or electronic capacity for real-time communication with the supervising physician (MD/DO). Technical criteria (mandatory) include that at least eight recording channels be available (16 if EEG is monitored) for all intraoperative neurophysiological monitoring. The remotely supervising physician must watch the tracings as they are obtained in real-time in the operating room, as well as the baseline electrophysiological test and the monitoring tracings from earlier in the case.   
  
Technical criteria (mandatory) for remote monitoring also include (a) routine
real-time auditory or written communication between the supervising physician
and the operating room and (b) the capability for telephone communications as
needed between the supervising physician and the monitoring technologist,
operating surgeon and the anesthesiologist.  
  

  7. The equipment must also provide for all of the monitoring modalities that may be applied with codes for auditory-evoked response, electroencephalography/electrocorticography, electromyography and nerve conduction and somatosensory-evoked response.  
  

  8. Undivided attention to a unique patient will be required during surgeries covered for this procedure. The monitoring physician must have a plan in place to transfer care to another physician, should any other situation arise during those times. When paying undivided attention to a unique patient, the physician must report services for only that one case during those times. Medicare will no longer consider it reasonable and necessary to reimburse additionally for this service in those cases where undivided attention is not required for one unique patient and will no longer reimburse a physician who performs more than one intraoperative neurophysiologic monitoring case simultaneously. All cases monitored, remote or those performed in the operating room require the exclusive undivided attention of the monitoring physician for consideration of Medicare coverage.  
  

  9. Medicare does not provide for reimbursement of "incident to" care in the hospital setting. More than one patient can no longer be monitored during the same fifteen minute interval of time. Claims for physician services must be submitted only for the time devoted to monitoring. This time, however, may be cumulative, and does not have to be continuous, i.e., two fifteen minute sessions or one-half hour of continuous attendance followed by another one-half hour later in the procedure will constitute one hour of monitoring.  
  

  10. Procedure codes for continuous intraoperative neurophysiological monitoring in operating room and continuous intraoperative neurophysiology monitoring, from outside the operating room describe 'ongoing monitoring'. This does not include services in which the information is stored and forwarded for a different time of review, or those services in which information is relayed by the technician to the physician who is not actually monitoring at the time.

**Place of Services (POS)**

The following POS may be allowed when covered indications and limitations are
met:

  * Off Campus-Outpatient Hospital
  * Inpatient Hospital
  * On Campus-Outpatient Hospital
  * Ambulatory Surgical Center

**Notice** : Services performed for any given diagnosis must meet all of the
indications and limitations stated in this policy, the general requirements
for medical necessity as stated in CMS payment policy manuals, any and all
existing CMS national coverage determinations, and all Medicare payment rules.
Refer to Billing and Coding: Intraoperative Neurophysiological Testing,
A56722, for applicable CPT/HCPCS codes and diagnosis codes.

The redetermination process may be utilized for consideration of services
performed outside of the reasonable and necessary requirements in this LCD.