Dr. Villalobos is a renowned neurophysiologist with a degree in Medicine and Surgery from the University of Seville, she specialized in Clinical Neurophysiology at the Virgen del Rocio University Hospital in Seville. In the following article she explains the importance of clinical neurophysiology to investigate diseases of the nervous system.
What is clinical neurophysiology?
Neurophysiology is a medical specialty, a branch of neurosciences, which deals with the study of the bioelectrical activity of the central, peripheral and autonomic nervous system. Through the use of advanced analytical equipment and techniques, this discipline aims to understand the functioning of the nervous system.
What is the objective of clinical neurophysiology?
Clinical neurophysiology studies the function and dysfunction of the nervous system caused by diseases of the brain, spinal cord, peripheral nerve, muscle and sense organs. For this purpose, physiological and imaging techniques are used to measure the activity of the nervous system. When the data obtained are interpreted in the clinical context of the patient, they allow diagnosing or helping to diagnose the neurological process, as well as quantifying, monitoring and assessing its evolution. Clinical neurophysiology also includes physiological methods for the treatment of neurological and psychiatric diseases.
What pathologies does a neurophysiologist treat?
Neurophysiology can perform the diagnosis of pathologies affecting different nervous systems.
- Central nervous system such as: epilepsy, cervical myelopathies, motor neuron diseases.
- Peripheral nervous system: neuropathies, polyneuropathies, reflex sympathetic dystrophy, radiculopathies.
- Motor plate and muscle diseases such as: Amyotrophic Lateral Sclerosis, Myasthenia Gravis, Myopathies.
- Intraoperative monitoring in surgical interventions such as: epilepsy surgery, deep brain stimulation in Parkinson, monitoring in brain and spine surgeries, aneurysm surgery, peripheral nerve and cranial nerve surgery.
What tests does a neurophysiologist perform?
- Electroencephalography
It consists of the recording of brain bioelectrical activity in resting, waking and sleeping conditions. It allows the diagnosis of diseases such as epilepsy, encephalopathies, coma states, diagnosis of brain death and others.
- Electromyography
A set of techniques that allow investigation of the function of peripheral nerves, nerve roots, neuromuscular junction or muscle. They are responsible for analyzing voluntary muscle activity and/or motor and sensory nerve conduction in various nerve segments.
- Evoked potentials
This test is responsible for recording the responses of the nervous system to specific, standardized sensory stimuli. Light stimuli are used to test the visual pathway, sound stimuli to evaluate the auditory pathway, electrical stimuli to evaluate the sensory pathway, etc.
- Polysomnography
Polysomnography records brain bioelectrical activity simultaneously with various cardiorespiratory and muscular activity variables that allow us to evaluate the characteristics, quantity and quality of sleep. It allows the diagnosis of sleep-related disorders such as sleep apnea-hypopnea syndrome, hypersomnias, narcolepsy, parasomnias, insomnia, etc.
- Intraoperative neurophysiological monitoring
It consists of the application of the previous techniques during those surgeries that present a high risk of producing a neurological lesion added to the patient’s previous pathology with the aim of preventing these lesions in those cases where it is possible. The techniques used are decided jointly between the neurophysiologist and the surgeon depending on the part of the nervous system at risk.
Its application is performed in the surgery of nervous system tumors (brain, spinal cord or nerves), vascular aneurysm surgery, some high-risk spine surgeries such as scoliosis, etc. Function maps are also elaborated with the objective of determining the situation of the eloquent brain areas in order to avoid their injury during surgery such as: language areas, motor area and sensitive area.