Most spinal procedures involve one, or a combination of the following:

• Removal of partial or all vertebral disc and replacement of disc space with an artificial device called a cage (Discectomy)
• Decompression/removal of tissue (i.e. bone, disc etc) that may be impinging on a nerve and causing pain
• Stabilizing of the spine by placement of rods and screws which help the spine to fuse (in the corrected position) as it heals (Fusion)
• Stabilization of a fractured or unstable vertebral body by either removing the fractured body and replacing the space with an artificial body (Corpectomy) or by insertion of a balloon into the vertebral body, which is inflated and then filled with a cement-like substance inside the fractured body (Kyphoplasty)
• Severing of overactive nerves roots that may be causing neuromuscular spasticity problems (Dorsal Rhizotomy)
• Spinal deformity cases are usually more case specific and may require other corrective action such as straightening of the spine with use of hooks, rods, screws etc (Scoliosis), or release of the spinal cord from attachment at the end of the spinal cord (Tethered Cord)

*While this doesn’t address all of the spinal procedures, it does address the most common procedures and what they may entail. The benefit of monitoring these spinal procedures is the ability to inform the doctor when the patient’s nerves are being irritated/damaged (allowing for immediate corrective action), to assist the doctor in safe and accurate placement of hardware (screws, rods, cages), and to identify changes that occur in the patients spinal cord function during surgery and make appropriate adjustments immediately.

The cranial procedures listed involve tumor removal, nerve decompression, or the repair of an artery. The location of the tumor or damaged artery/nerve, will dictate what structures and/or nerves we will monitor and what tests will be run during the procedure. Monitoring is also used to help the doctor identify specific cranial nerves (which are responsible for a wide range of functions including facial expression and sensation, hearing, eye sight, taste, ability to swallow etc) or other important structures so that they may be preserved, protected, and avoided. Because arteries are responsible for supplying blood/oxygen to certain areas of the brain, it is essential that we monitor the activity of the areas of the brain that rely on blood from the damaged artery. A decrease in activity is a warning to the technician and the surgeon that there may be an insufficient amount of blood flow and call for a change of action.

ENT stands for Ear, Nose, and Throat. During the mentioned ENT procedures, the doctor has to work near the facial nerve (which allows us to smile, wink, and move our lips) and recurrent laryngeal nerve (which innervates our vocal cords and allows us to speak). By monitoring the muscle activity of several facial muscles (around the eye and around the lips) and/or the vocal cord muscles, we are able to identify when these nerves are being touched, stretched, or in any way irritated; this helps avoid patients waking up with sore throat, scratchy voice, or loss of function of their facial muscles.

At times, during peripheral procedures, such as hip procedures, the blood flow to limbs is cut off due to patient positioning required for the surgery (this lack of blood flow is the same thing as when your arm falls asleep during the night or when your leg falls asleep from sitting for too long). When blood flow is cut off, it leads to ischemia and if the cells in our body are ischemic (lacking blood flow) for too long, it may lead to cell death. In normal, everyday life your body recognizes ischemia and tells you to adjust things to allow blood to flow. By monitoring the involved limbs and nerves that are at risk of ischemia, we are able to help identify and prevent or correct this lack of blood flow when it occurs as well as identify when nerves are irritated.

In most vascular procedures, our primary goal is to identify when certain areas of the brain/body aren’t receiving proper blood flow. Often times, doctors need to clamp an artery shut in order to remove plaque (such as in a CEA procedure), remove a tumor, or repair a blood vessel. During this time of being clamped, we are able to run tests and quickly identify areas of the brain or spinal cord that aren’t receiving enough oxygen/blood flow. This allows the doctor to make a decision to place a shunt (an alternate, artificial pathway for blood to flow through while the main artery is clamped shut) thereby restoring blood flow to the area that was lacking when the artery was clamped.