Clinical Neurophysiology

Clinical neurophysiology plays a critical role in neurosurgery by providing real-time functional assessment of the nervous system, guiding surgical decisions, and improving patient outcomes. The integration of neurophysiological techniques in neurosurgical procedures has significantly enhanced safety and precision.

• Visualization of functional and effective connectivity underlying auditory descriptive naming
• Differential electroencephalogram findings depending on type of praxis in reflex epilepsy
• The role of community pharmacists in managing common headache disorders, and their integration within structured headache services: position statement on behalf of the European Headache Federation (EHF) and Lifting The Burden (LTB: the Global Campaign against Headache), with the formal endorsement of the International Pharmaceutical Federation
• Bilateral Focused Ultrasound Thalamotomy for Essential Tremor: Clinical Outcomes Compared to Bilateral Deep Brain Stimulation and Probabilistic Lesion Mapping
• Specialized Large Language Model Outperforms Neurologists at Complex Diagnosis in Blinded Case-Based Evaluation
• Transorbital Transsylvian Selective Amygdalohippocampectomy: A Feasibility Anatomic Investigation
• Median nerve compression by the ligament of Struthers: Clinical Image
• Risk Factors for Neurological Deficits Following Brain Tumor Resection in the Supplementary Motor Area (SMA): A 66-Case Double-Center Study

Clinical neurophysiology supports neurosurgery in three key areas:

• Diagnosis of Neurological Disorders:
  • EEG for epilepsy surgery planning.
  • EMG and nerve conduction studies for peripheral nerve pathologies.
  • Evoked potentials for multiple sclerosis and spinal cord disorders.
• Functional Brain Mapping:
  • Identifies eloquent cortical areas (e.g., motor, language regions) before tumor resection.
  • High-density EEG and magnetoencephalography (MEG) locate epileptogenic foci.

IONM is essential for preventing neurological deficits during surgery. Techniques include:

• Continuous EEG monitoring in ICU patients with brain injury or post-surgical complications.
• Evaluation of functional recovery through nerve conduction studies (NCS) and EMG in patients with peripheral nerve injuries.

• Intracranial EEG (iEEG) and ECoG help localize seizure foci.
• Cortical stimulation mapping ensures the safe removal of epileptogenic tissue.

• Awake craniotomy with neurophysiological monitoring preserves language and motor functions.
• Electrocorticography detects epileptogenic activity around tumors.

• Intraoperative Neurophysiological Monitoring prevents spinal cord and nerve root damage.
• EMG identifies nerve compression in brachial/lumbosacral plexopathies.

• Deep Brain Stimulation (DBS) for movement disorders (Parkinson’s, dystonia).
• Cortical and spinal cord stimulation for pain management.

• Reduces postoperative neurological deficits.
• Enhances surgical precision and safety.
• Improves patient outcomes and quality of life.

• Artificial Intelligence in Electroencephalography/MEG interpretation.
• High-density Electroencephalography functional magnetic resonance imaging.
• Closed-loop neurostimulation for epilepsy and movement disorders.

Clinical neurophysiology is indispensable in modern neurosurgery, providing functional guidance before, during, and after surgery to optimize patient safety and improve surgical outcomes.

In the 18th century, Luigi Galvani proposed the hypothesis of animal electricity, which is produced by the brain and distributed through the nerves to the muscles. This was the cornerstone of what is known today as the modern study of nerve function, earning him the title of the Father of Clinical Neurophysiology. The 19th century was subsequently marked by two major figures: Santiago Ramón y Cajal (Neuron Theory) and Hans Berger, known for describing cerebral electrical activity and recording the first electroencephalograms. In Mexico, Clinical Neurophysiology emerged in the late 19th century and consolidated itself in the first half of the 20th century. In the year of 1938, Dr. Clemente Robles and Teodoro Flores Covarrubias built the first electroencephalograph, marking the beginning of the era of Clinical Neurophysiology. Initially, this diagnostic tool was primarily applied to psychiatric patients, as there was no clear separation between psychiatry and neurology, and patients were treated jointly at the largest psychiatric center of that time, “La Castañeda.” In 1968, the Mexican Society of Electroencephalography A.C. was founded and later changed its name to the Mexican Society of Clinical Neurophysiology A.C. Simultaneously, its members achieved universal recognition of the medical specialty, which has become established in clinical practice and has shown progressive academic and scientific growth in Mexico ¹⁾