Neuromonitoring​

Neuromonitoring is a technique that enables the real-time monitoring of neural system functions, particularly during neurosurgical procedures. In the field of neurosurgery, the preservation of neural pathways and brain functions is of critical importance. With neuromonitoring, neural stimuli can be detected instantaneously, allowing surgical strategies to be adjusted in real-time. This technological approach helps ensure that surgery is performed safely and effectively.

The Role of Neuromonitoring in Neurosurgery

Neuromonitoring plays a crucial role in protecting neural pathways during neurosurgical procedures. Techniques such as EMG, EEG, SEP, MEP, BAEP, and VEP enable the real-time monitoring of neural function during brain surgeries. These technological methods allow surgeons to detect changes in neural activity during surgery and make necessary adjustments to their approach.

Given the delicate and high-risk nature of brain surgery, the importance of neuromonitoring becomes even more evident. Neurosurgeons, neurologists, and neuromonitoring technicians work closely together to ensure that the process runs smoothly and safely. While neurologists interpret data to assess the healthy functioning of neural pathways, neuromonitoring technicians ensure the proper functioning of the equipment, collect signals, and provide real-time information to the surgeon. This collaboration is essential in safeguarding neural integrity and minimizing complications.

Neuromonitoring Techniques

Neuromonitoring can be performed using a variety of techniques, which may vary depending on the type of surgery and the patient’s condition. The most commonly used neuromonitoring techniques include:

• Intraoperative Motor Evoked Potential (MEP) Monitoring:  Motor evoked potentials (MEP) measure the electrical responses to stimuli that cause muscle contractions. This method is commonly used in brain and spinal surgeries to monitor the safety of nerve roots and the spinal cord. MEP enables rapid detection of any changes in nerve activity.
• Somatosensory Evoked Potentials (SSEP): Sensory evoked potentials (SSEP) measure the electrical responses from the sensory nervous system to electrical stimuli applied to the body. This technique continuously monitors nerve conduction during brain and spinal surgeries. Abnormal SSEP responses alert the surgeon to reevaluate and adjust the surgical procedure as needed.
• Electroencephalography (EEG): EEG measures the electrical activity of the brain and is particularly useful in monitoring brain function during surgery. This technique is crucial in detecting abnormal brain activity, such as seizures or ischemic changes, that could indicate neural compromise. EEG is commonly used in brain surgeries to ensure that critical brain regions are not damaged during the procedure. It also helps in monitoring the depth of anesthesia, ensuring that the patient’s brain activity is properly managed during surgery.
• Electromyography (EMG): Electromyography (EMG) records the electrical activity of muscles, particularly useful in monitoring peripheral nerves and nerve root activities. Surgeons can detect abnormal electrical activity in muscles using EMG, allowing for the early identification of potential neural damage.
• Brainstem Auditory Evoked Potentials (BAEP): BAEP (Brainstem Auditory Evoked Potentials) measures the electrical responses from the brainstem to auditory stimuli. This method monitors brainstem function. Particularly useful during brain and spinal surgeries, BAEP evaluates the communication between auditory pathways and the brainstem. Surgeons can detect functional changes in the brainstem and adjust the procedure to minimize damage to neural pathways.
• Visual Evoked Potentials (VEP): VEP is the measurement of the electrical responses generated by the brain to visual stimuli, such as a light or a specific visual pattern. This method is primarily used to assess the health and function of the visual pathways (optic nerves and visual cortex). VEP is typically used to detect conditions that may affect the visual system, which are not visible to the naked eye. This test is a crucial tool for monitoring and detecting damage in the visual pathways. The electrical responses recorded from the brain show how signals are transmitted from the eyes to the brain, allowing surgeons to monitor the preservation of the visual pathways in real-time.
• Brain Mapping: Brain mapping is a technique used to identify and locate critical functional areas of the brain before or during surgery. This can include identifying areas responsible for motor functions, sensory input, speech, and vision. Brain mapping, particularly through direct cortical stimulation, helps surgeons navigate around sensitive regions and avoid damaging essential brain structures. This technique is especially beneficial in brain tumor surgeries or when removing tissue in regions associated with critical functions.
• Awake Craniotomy: In an awake craniotomy, the patient is kept awake during the procedure, typically for surgeries involving the brain’s motor or speech areas. This technique allows surgeons to interact with the patient and assess their cognitive or motor responses in real time, helping to ensure that key functional areas are preserved. The use of neuromonitoring in awake craniotomy procedures, combined with direct feedback from the patient, enhances the surgeon’s ability to avoid or helps prevent damage to critical brain regions while performing necessary operations.