Intraoperative Neurophysiological Monitoring is used during complex surgeries, such as surgery on the brain or spinal cord. This monitoring is performed to provide your surgeon with feedback during your surgery on the function of your nervous system. There is an assortment of monitoring tools and techniques that may be used by your surgeon in different combinations in order to provide the surgeon useful information regarding your condition as your surgery progresses.

Our surgical neurophysiologist will be in the Operating Room participating in your surgery. Prior to surgery, our surgical neurophysiologist will attach a series of electrodes at different points along your nerve pathways to monitor your nervous system. The location of the electrodes will depend on the type of surgery being performed and on your condition.

The information regarding the function of your nervous system will also be monitored remotely by one of Sentient’s supervising neurologists. This is accomplished using sophisticated telemedicine technology that is detailed, highly reliable, and secure. Sentient’s surgical neurophysiologist and supervising neurologist will confer with one another regarding any changes in your condition and will communicate that information to your surgeon.

Sentient is one of the nation’s largest providers of Intraoperative Neurophysiological Monitoring. Sentient’s staff is made up of extensively trained surgical neurophysiologists with a minimum of a bachelor’s degree and CNIM certification and supervising neurologists who are Board Certified or generally Board Eligible Medical Doctors.

Neurosurgery Procedures

Surgical Monitoring

Neurosurgery Procedures (including but not limited to):


  • Excision of primary and secondary neoplasia from supratentorial and infratentorial locations (including CPA locations for schwannomas)
  • Microvascular decompression procedures
  • Intracerebral aneurysm and AVM surgery
  • Glomus tumor resection and jugular foramen procedures including skull base surgery
  • Arnold Chiari Malformations

Other Procedures on Extracranial and Intracranial Arteries

  • Carotid endarterectomy
  • EC-IC bypass procedures

Spinal Procedures

  • Intradural abscess or neoplasm resection
  • Drainage and marsupialization of cysts including syrinxes
  • Procedures on the Cauda Equina including removal of lipomas, and cord untethering
  • Monitoring spinal cord stimulator placement
  • Spinal AVM surgery

Funtional Neurosurgery (supervision of Doctoral Neurophysiologists in the OR is directly by the Neurosurgeon)

  • Deep brain stimulation for Parkinsonism, tremors, dystonias and other movement disorders

Interventional Procedures

  • Embolization of intracranial and extracranial/spinal arteriovenous malformations
  • Embolization of intracranial and extracranial/spinal aneurysms
  • Endovascular chemotherapy
  • Reperfusion with t-PA and other lytic agents
  • Endovascular atherothrombectomy
  • Intracranial and extracranial stent placement
  • Angioplasty of intracranial and extracranial vessels

Cranial and Peripheral Nerve Procedures

  • Tumor resection including schwannomas/sarcomas of cranial/peripheral nerves
  • Exploration of brachial plexus
  • Exploration of post-traumatic peripheral nerves- anastomosis procedures
Orthopedic Surgery Procedures

Orthopedic Surgery Procedures

Orthopedic Surgery Procedures (including but not limited to):

Anterior/Posterior Spinal Fusion with/without Instrumentation

  • Cervical (including C1/2 for spinal instability)
  • Thoracic
  • Thoracolumbar
  • Lumbosacral
  • Multilevel

Pedicle Screw Insertion Monitoring

  • Thoracic
  • Thoracolumbar
  • Lumbosacral
  • Multilevel

Intradural, Extramedullary and Intramedullary Surgery

  • Removal of primary and secondary neoplasia of the spine
  • Removal of benign lesions of the spinal cord and peripheral nerves
  • Implantation of spinal stimulators
  • Untethering of cauda equina

Monitoring of Patients’ Positioning During Surgery

  • Peripheral nerve compression
  • Brachial plexus stretching

Open Reduction and Internal Fixation

  • Pelvis
  • Other sites

Spinal Decompression with/without Discectomy

  • Cervical (including C1/2 for spinal instability)
  • Thoracic
  • Thoracolumbar
  • Lumbosacral
  • Multilevel

Minimally Invasive Procedures

  • ALIF
  • XLIF
  • TLIF

Correction of Spinal Curvature

  • Scoliosis surgery
  • VEPTR rod insertion
  • VEPTR rod lengthening procedures


  • Shoulder
  • Hip
  • Knee


  • Discography
  • Triangle tilt procedure
Frequently Asked Questions

Frequently Asked Questions

Q: Who is Sentient?

A: Sentient is one of the nation’s largest providers of neurointraoperative monitoring. Sentient is staffed by extensively trained surgical neurophysiologists with various medical and biological degrees from a bachelor’s degree to Ph.D./M.D. levels. The surgical neurophysiologists have a high level of expertise and knowledge in the field of neurointraoperative monitoring.

Providing continuous neurological consultative supervision is a staff of trained and experienced supervising neurologists who are generally board certified and have subspecialtay fellowship training in Clinical Neurophsyiology.

Q: What is Intraoperative Neurophysiological Monitoring (IONM) and why do we use it?

A: IONM is the application of various tests to monitor the neural structures that are at risk during your surgery (e.g., spinal cord, brain) to reduce the risk of negative outcomes such as paralysis or stroke. IONM helps protect the integrity of your neural structures during your surgery and, in so doing, it is an additional layer of safety for you and your surgeon.

Q: What role does the IONM surgical neurophysiologist play during my surgery?

A: Typically, electrodes are attached to your wrists, ankles, head, and if necessary, specific muscle groups. As the surgical neurophysiologist is monitoring the information received from the electrodes, s/he will immediately alert the surgeon of any significant changes so that the surgeon may initiate appropriate intervention strategies.

Q: Who requested IONM for my surgery?

A: Your surgeon has requested that a Sentient surgical neurophysiologist be present during your surgery and for a Sentient supervising physician to monitor your surgery to provide additional safety for you and your surgeon.

Q: What are the risks of IONM?

A: The risks of IONM are minimal. There is a remote chance of infection from the electrodes. There remains the possibility that you will have neurological deficits as a result of your surgery despite having IONM. Consult your surgeon to discuss the risks of surgery.

Q: Who pays for IONM?

A: Your insurance carrier may pay for a portion of the costs associated with IONM. This amount depends on your specific carrier and your plan. You may be responsible for payment of the difference.

Q: Who should I contact if I have more questions?

A: Please feel free to call Sentient at 888-481-9185 or write us at