IONM, includes somatosensory-evoked potentials, motor-evoked potentials using transcranial electrical stimulation, brainstem auditory-evoked potentials, electromyography (EMG) of cranial nerves, electroencephalogram (EEG), and electrocorticography (ECoG), may be considered medically necessary for ANY of the following procedures:
- Aortic arch, its branch vessels, or thoracic aorta surgery, including carotid artery surgery, when there is risk of cerebral or spinal cord ischemia; or
- Aortic procedures, distal, where there is risk of ischemia to spinal cord; or
- Arteriovenous malformations (AVMs), surgery or embolization for intracranial AVMs; or
- Basal ganglia movement disorders; or
- Brain, deep stimulation; or
- Brain, resection of epileptogenic tissue or tumor; or
- Brain, resection of tissue close to the eloquent brain cortex and requiring brain mapping; or
- Brain surgery as a result of traumatic injury; or
- Bronchial artery arteriovenous malformations or tumors, embolization of; or
- Carotid artery arteriography, during which there is a test occlusion of the carotid artery; or
- Cerebral vascular aneurysms; or
- Circulatory arrest with hypothermia [does not include surgeries performed under circulatory bypass (e.g., coronary artery bypass grafting (CABG), ventricular aneurysms); or
- Cranial nerve protection during:
- Resection of tumors involving the cranial nerves; or
- Cavernous sinus tumors; or
- Microvascular decompression of cranial nerves; or
- Skull base surgery in the vicinity of the cranial nerves and surgeries of the foramen magnum; or
- Oval or round window graft; or
- Endolymphatic shunt for Meniere's disease; or
- Leg lengthening procedures, where there is traction on sciatic nerve or other nerve trunks; or
- Movement disorders, surgery for intractable movement disorders; or
- Peripheral nerves, neuromas of the brachial plexus, when there is risk to major sensory or motor nerves; or
- Responsive neurostimulation for epilepsy; or
- Spinal cord, arteriovenous malformation surgery; or
- Spinal cord, correction of scoliosis or deformity of the spinal cord involving traction of the cord; or
- Spinal cord, 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; or
- Spinal cord, protection where work is performed in proximity to cord and nerve roots as in the placement of new instrumentation or removal of old hardware or where there have been numerous interventions; or
- Spinal cord surgery as a result of traumatic injury; or
- Spinal cord tumors and spinal fractures (with the risk of cord compression); or
- Spinal instrumentation requiring pedicle screws, disc arthroplasty or distraction; or
- Vestibular section for vertigo.
IONM of the recurrent laryngeal nerve may be consideredmedically necessaryin individuals undergoing:
- Anterior cervical spine surgery associated with any of the following increased risk situations:
- Multilevel anterior cervical discectomy and fusion; or
- Preexisting recurrent laryngeal nerve pathology, when there is residual function, revision surgery through a scarred surgical field, reoperation or revision for failed fusion.
- Prior anterior cervical surgery, particularly revision anterior cervical discectomy and fusion, revision surgery through a scarred surgical field, reoperation for pseudarthrosis, or revision for failed fusion.
- High-risk thyroid or parathyroid surgery, including:
- Repeat thyroid or parathyroid surgery; or
- Retrosternal or giant goiter; or
- Surgery for cancer; or
- Thyrotoxicosis; or
- Thyroiditis; or
- Total thyroidectomy.
IONM of the recurrent laryngeal nerve during anterior cervical spine surgery not meeting the criteria above or during esophageal surgeries is consideredexperimental and investigational and therefore, non-covered because the safety and /or effectiveness of this service cannot be established by the available peer-reviewed literature.
Intraoperative monitoring of visual-evoked potentials is considered experimental/investigational and therefore, non-covered because the safety and /or effectiveness of this service cannot be established by the available peer-reviewed literature.
Intraoperative monitoring of motor-evoked potentials using transcranial magnetic stimulation is considered experimental/investigational and therefore, non-covered because the safety and/ or effectiveness of this service cannot be established by the available peer-reviewed literature.
IONM for any other procedure not listed above is considered not medically necessary.
Intraoperative EMG and nerve conduction velocity monitoring during surgery on the peripheral nerves is considered not medically necessary.