We report the case of somatosensory evoked potential loss during a transforaminal interbody fusion during exposure following a transient rise in blood pressure. The topography of signal loss and elimination of technical causes led to the inference of left sided stroke which was confirmed as a left thalamocapsular hemorrhagic infarct on postoperative magnetic resonance imaging. Use of intraoperative neuromonitoring in this lumbar fixation surgery helped to identify it intraoperatively and prevented undue alternative surgical decision making.

The vestibular system, essential for balance and spatial orientation, spans from the inner ear to various brain regions. Advances in imaging techniques have significantly enhanced our ability to diagnose and treat vestibular disorders. This review explores the anatomy of the vestibular system and evaluates the roles of high-resolution computed tomography (CT) and magnetic resonance imaging (MRI) in diagnosing structural abnormalities. CT is particularly useful for identifying bony labyrinth anomalies, temporal bone fractures, and superior canal dehiscence, though it has limitations in visualizing membranous labyrinth lesions. MRI, with its superior soft tissue resolution, is preferred for detecting retrocochlear lesions such as vestibular schwannomas, cerebellopontine angle tumors, and demyelinating diseases in the posterior fossa. Functional MRI also offers insights into the vestibular system’s functional aspects. The review emphasizes the increasing importance of imaging diagnostics in the effective management of vestibular system diseases, highlighting both structural and functional imaging modalities to improve patient outcomes.

The electrical signals that pass through neuronal structures generate electrical currents and magnetic fields that can be measured by different electrography and magnetography modalities. In this article, we briefly review the fundamentals of recording bioelectrical currents and biomagnetic fields. This is followed by an analysis of the neurophysiologic substrates of the brachial plexus, cervical roots, and spinal cord, comparing the electrography-based modality of somatosensory evoked potential with the magnetography-based modality of magnetospinography/magnetoneurography (MSG/MNG). We aim to illustrate that MSG/MNG has the potential to address the shortcomings that currently exist in electrography modalities for direct neurophysiologic assessment of the aforementioned neural structures.

Background: This study aimed to determine the effects of perampanel on the nervous system using commonly performed neurophysiological tests. Methods: Twelve healthy adult males underwent electroencephalogram and measurements of median nerve somatosensory evoked potentials (SSEPs), visual evoked potentials (VEPs), and brainstem auditory evoked potentials before and after ingesting 6 mg of perampanel. The pre- and postadministration data were cross-compared and then correlated with serum perampanel levels and reported side effects. Results: After ingesting 6 mg of perampanel there was a statistically significant increase in the P100 latency of VEPs elicited using a 64 × 64 checkerboard pattern (p = 0.027) and a decrease in the N20 latency of median nerve SSEPs (p = 0.033). Reported side effects were not correlated with the serum perampanel level or statistically significant latency changes. Conclusions This study is the first to explore the effects of perampanel on results obtained in neurophysiological tests. Our findings indicate that perampanel increases sensory conduction, as evidenced by a decrease in N20 latency. Perampanel may additionally interfere with visual processing, in part by prolonging P100. Further studies with larger samples and various doses are needed to clarify these findings.

Background: Electromyography and nerve conduction studies (EMG-NCS) often yield nonspecific findings during the early stage of Guillain-Barré syndrome (GBS). Although useful for diagnosis, EMG-NCS are traditionally of little value in predicting a complicated clinical course, which is critical for timely decisions to initiate immunomodulatory treatment. We aimed to identify the early clinical and electrophysiologic predictors of respiratory failure, a prolonged hospital stay, and moderate-to-severe disability at discharge in GBS. Methods: We retrospectively analyzed the clinical and electrophysiologic data of adult GBS patients who were hospitalized during the early course of the disease (<2 weeks from symptom onset). Results: Eighty-one patients aged 47.5 ± 16.1 years were analyzed. The most common clinical variants were Miller-Fisher syndrome (30.9%) and classic sensorimotor GBS (25.9%). The clinical variant was not predictive of a complicated clinical course. Instead, specific clinical features such as dysautonomia (p = 0.006) and marked motor deficits (p = 0.002) were predictive of the primary composite outcome of respiratory failure and/or a prolonged hospital stay, with dysautonomia (p = 0.035) also predictive of moderate-to-severe disability at discharge. The most common abnormalities in EMG-NCS were bilateral absence of the H-reflex (86.4%) and F-wave abnormalities (44.4%). The presence of F-wave abnormalities was predictive of both respiratory failure (p = 0.032) and a prolonged hospital stay (p = 0.001). Conclusions Early F-wave abnormalities in GBS may serve as an electrophysiologic predictor of a complicated clinical course, suggesting that EMG-NCS can provide prognostic information to guide treatment decisions during the early stage of the disease.

Narcolepsy is a central disorder of hypersomnolence primarily characterized by excessive daytime sleepiness often accompanied by cataplexy, sleep paralysis, hypnagogic hallucinations, and disrupted nocturnal sleep. Pathophysiological mechanisms involve genetic predisposition, hypocretin deficiency, infectious and immune-related factor. Diagnosis is established through clinical evaluation, polysomnography, multiple sleep latency testing, and cerebrospinal fluid hypocretin measurement. Pharmacological treatment primarily aims to alleviate excessive daytime sleepiness (EDS) and cataplexy. Stimulants such as modafinil and solriamfetol are commonly used for managing EDS, while antidepressants are employed to control cataplexy. Pitolisant and sodium oxybate have demonstrated efficacy in treating both EDS and cataplexy. This review summarizes current understanding of the epidemiology, clinical features, pathophysiology, diagnostic approaches, and therapeutic options for narcolepsy.

We report a genetically confirmed case of adult-onset Alexander disease (AOAD) presenting with progressive dysarthria and palatal tremor. Brain magnetic resonance imaging revealed medullary atrophy and olivary hyperintensities. A pathogenic variant of the glial fibrillary acidic protein gene (p.R416W) was identified. The palatal tremor indicated involvement of the Guillain-Mollaret triangle. This case underscores the diagnostic value of bulbar signs and neuroimaging in AOAD and highlights the importance of integrating clinical, radiological, and genetic findings for early definitive diagnosis.

Rippling muscle disease (RMD) is caused by dominant mutations of the caveolin-3 gene (CAV3), and presents with overlapping limb-girdle muscle weakness, elevated creatine kinase (hyper- CKemia), RMD, and distal myopathy. We report a patient with a CAV3 mutation who presented with myalgia, exercise-induced muscle stiffness, hyperCKemia, and percussion-induced rapid muscle contraction and muscle mounding. A familial genetic study revealed the same mutation in two family members, with physical examinations showing that both of them had rippling muscles.