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 The brain magnetic resonance imaging (MRI) findings seen in patients with Bell's palsy are abnormal contrast enhancement of affected facial nerves. Previous evaluation included mainly patients who had experienced palsy for several weeks and there are no studies to date on patients with late stage of Bell’s palsy. This study investigated the findings of MRI of Bell's palsy after 3 months of symptom onset to assess how long the enhancement last.
Methods Among the patients with Bell's palsy (idiopathic unilateral facial palsy) who visited the hospital, 9 patients who underwent contrast-enhanced MRI of the internal auditory canal after 3 months of symptom onset were reviewed retrospectively. MRI examination results were investigated along with the patient's clinical symptoms and electrodiagnostic test results. Based on the MRI results, the frequency of abnormal contrast enhancement and contrast-enhanced areas were investigated.
Results 9 patients were included. 6 of them did MRI imaging because of incomplete recovery of facial palsy and the others did because of complication of facial palsy including synkinesis and hemifacial spasm. Time interval between symptom onset and evaluation was 17 months (3-84). Of 9 patients, 2 showed abnormal enhancement of affected nerve and they performed MRI after 5 months and 12 months of symptom onset, respectively.
Conclusions Abnormal enhancement of facial nerve in Bell’s palsy could last up to one year. This awareness can be helpful in interpretation of MRI of Bell’s palsy.
Bell's palsy is one of the most common outpatient problems in neurologic clinics. The diagnosis of Bell's palsy is typically made through clinical evaluation. Characteristic findings include the acute onset of unilateral lower motor neuron facial paralysis, reaching its peak within 72 hours. However, there are numerous diagnostic pitfalls related to the differential diagnosis, including neoplasms, autoimmune disorders, trauma, and infections. For an accurate diagnosis, recognizing the anatomical background and identifying atypical clinical features of Bell's palsy is crucial. Oral steroids are considered the optimal treatment, and antiviral agents may play a beneficial role. Even without treatment, the prognosis for Bell's palsy is generally favorable, but long-standing sequelae are also possible and should be considered for functional, aesthetic, and psychological aspects.
AGel amyloidosis is an autosomal dominantly inherited disease caused by a GSN mutation, and affected patients typically present with the clinical triad of corneal lattice dystrophy, progressive cranial neuropathy, and cutis laxa. We report a Korean family with AGel amyloidosis with predominant manifestations of facial and bulbar muscle weakness. Whole-exome sequencing revealed a common missense mutation (p.Asp214Tyr) in GSN. This case strongly suggests that AGel amyloidosis should be considered when a patient presents with progressive facial and bulbar palsies.
Facial diplegia (FD) rarely occurs as a regional Guillain-Barré syndrome (GBS) variant. A 70-yearold male presented with bifacial weakness that had started on the left side and extended to the right after several days. He was then treated using steroids and gradually improved. Serum antiganglioside antibody testing revealed positivity for anti-GM1 IgG antibodies. FD can be idiopathic, but it is an uncommon GBS variant. The ganglioside antibody test may increase the possibility of diagnosing isolated FD.
Peripheral facial palsy is often reported after surgery for head or neck tumors and otolaryngologic surgery, but the occurrence of facial nerve palsy after dental procedures is very rare. A 29-year-old man visited our clinic with right-side facial asymmetry and right facial weakness 7 days before. The patient underwent dental treatment 8 days ago. He exhibited weakness of the right side of his face and was unable to close his right eye. He was diagnosed with right-sided peripheral type facial nerve paralysis and treated with an antiviral agent and prednisolone, and the symptoms gradually improved. Facial nerve palsies after dental procedures have been reported in foreign countries, but these cases have been very rarely reported in Korea. We also reported on the efficacy of the conventional treatment of facial nerve palsy after a dental procedure.
Background Unilateral peripheral facial nerve palsy may have a detectable cause (secondary facial nerve palsy) or may be idiopathic (Bell’s palsy). Facial palsy is attributable to various causes ranging from mild infection to severe neurological disorders. We investigated the prevalence and types of serious neurological disorders in patients with unilateral facial palsy.
Methods We reviewed the medical records of patients with unilateral facial nerve palsy and identified patients diagnosed with facial palsy secondary to serious or life-threatening causes. We investigated the clinical characteristics, as well as electrodiagnostic and imaging findings in these patients.
Results Of 924 patients with facial palsy, 11 patients (1.2%) were diagnosed with the following serious neurological disorders: acoustic schwannoma in two patients, facial nerve schwannoma, glossopharyngeal schwannoma, meningioma, epidermoid cyst, parotid gland tumor, pontine infarct, skull base osteomyelitis, brain metastasis, and pachymeningitis.
Conclusions Although unilateral facial palsy is rarely associated with serious neurological disorders, early detection of the etiopathogenetic contributors is important for prompt initiation of optimal management. Therefore, clinicians should be mindful of disorders that can mimic Bell’s palsy.
Visual evoked potentials (VEPs) are especially useful for evaluating patients with visual pathway involvement but no objective findings on ophthalmic examination. To apply VEPs appropriately in clinical practice, clinicians should be well aware of the standard test techniques and various factors affecting the interpretation of VEPs to detect visual pathway abnormalities. This article summarizes the method for recording VEPs and the technical and physiologic factors associated with VEPs.
Cortico-cortical evoked potential (CCEP) mapping is a rapidly developing method for visualizing the brain network and estimating cortical excitability. The CCEP comprises the early N1 component the occurs at 10-30 ms poststimulation, indicating anatomic connectivity, and the late N2 component that appears at < 200 ms poststimulation, suggesting long-lasting effective connectivity. A later component at 200-1,000 ms poststimulation can also appear as a delayed response in some studied areas. Such delayed responses occur in areas with changed excitability, such as an epileptogenic zone. CCEP mapping has been used to examine the brain connections causally in functional systems such as the language, auditory, and visual systems as well as in anatomic regions including the frontoparietal neocortices and hippocampal limbic areas. Task-based CCEPs can be used to measure behavior. In addition to evaluations of the brain connectome, single-pulse electrical stimulation (SPES) can reflect cortical excitability, and so it could be used to predict a seizure onset zone. CCEP brain mapping and SPES investigations could be applied both extraoperatively and intraoperatively. These underused electrophysiologic tools in basic and clinical neuroscience might be powerful methods for providing insight into measures of brain connectivity and dynamics. Analyses of CCEPs might enable us to identify causal relationships between brain areas during cortical processing, and to develop a new paradigm of effective therapeutic neuromodulation in the future.
Citations
Citations to this article as recorded by
The impact of radiofrequency thermocoagulation on brain connectivity in drug‐resistant epilepsy: Insights from stereo‐electroencephalography and cortico‐cortical evoked potentials Justyna Gula, Rutger J. Slegers, Raf H. M. Van Hoof, Balu Krishnan, Massimo Mischi, Vivianne H. J. M. van Kranen‐Mastenbroek, Ilse E. C. W. Van Straaten, Danny Hilkman, Louis Wagner, Albert Colon, Olaf E. M. G. Schijns, Borbála Hunyadi, Jacobus F. A. Jans Epilepsia.2025; 66(4): 1260. CrossRef
Recent developments in stereo electroencephalography monitoring for epilepsy surgery Debopam Samanta Epilepsy & Behavior.2022; 135: 108914. CrossRef
Bell’s palsy is an acute peripheral facial paralysis with no detectable cause. Although the prognosis of Bell’s palsy is generally good, some patients experience poor recoveries and there is no established treatment for those that do not recover even after receiving the conventional treatment. Here we present two cases of refractory Bell’s palsy with facial nerve enhancement in magnetic resonance imaging who showed symptomatic improvement after the late administration of high-dose intravenous methylprednisolone.
Citations
Citations to this article as recorded by
Development of the Korean Medicine Core Outcome Set for Facial Palsy: herbal medicine treatment of patients with facial palsy in primary clinics Soo-Dam Kim, Sungha Kim, Mi Ju Son, Jiyun Cha, Pyung-Wha Kim, Mi Mi Ko, Soobin Jang, Changsop Yang, Myeong Soo Lee Frontiers in Medicine.2024;[Epub] CrossRef
In Guillain-Barré syndrome (GBS) and its variant, anti-GQ1b antibody has a pathogenic role for ophthalmoplegia. In addition, anti-GT1a antibody is related with lower cranial nerve involvement. This report describes a 60-year-old male patient with GBS manifesting with initially isolated dysphagia and subsequently developed ophthalmoplegia. Both immunoglobulin G type anti-GQ1b and anti-GT1a antibodies were detected in the patient’s serum. A mechanism regarding subsequent involvement of respective cranial nerves remains to be elucidated.
Vestibular-evoked myogenic potentials (VEMPs) are useful for evaluating the vestibulocollic reflex arising mostly from the saccule and the vestibuloocular reflex originating from the utricle. VEMPs can vary with the characteristics of the applied stimuli and the effects of aging and diseases. VEMPs have been found to be useful for diagnosing superior canal dehiscence, but their usefulness for other clinical disorders remains unclear. This review discusses the principles of VEMP tests and summarizes the findings for VEMPs in common vestibular disorders.
Citations
Citations to this article as recorded by
Inferior Vestibular Neuritis: Diagnostic Criteria, Clinical Features, and Prognosis—A Focused Review Gabriela Cornelia Musat, Mihai Alexandru Preda, Ionut Tanase, Adina Zamfir Chiru Anton, George G. Mitroi, Ovidiu Musat, Alina Lavinia Antoaneta Oancea, Mihaela Roxana Mitroi Medicina.2025; 61(2): 361. CrossRef
A scoring chart to evaluate cases of probable vestibular migraine Haider Alsarhan Hearing Balance and Communication.2023; 21(3): 162. CrossRef
A 21-year-old soldier was admitted due to weakness after carrying a heavy military bag and marching for a long time. Neurophysiologic investigation revealed prominent involvement of right brachial plexus and upper cervical root with mild abnormalities of multiple nerves in the other extremities. Hereditary neuropathy with liability to pressure palsy was confirmed by gene test demonstrating deletion of PMP22 gene. This study presents backpack palsy can appear as a first manifestation of hereditary neuropathy with liability to pressure. The possibility of hereditary neuropathy with liability should be strongly considered in a young patient with non-symptomatic multiple neuropathy.
A 64-year-old man presented with facial diplegia occurring 2 weeks after scrub typhus diagnosis. The serum scrub typhus antibody titer was elevated to 1:5120. Brain magnetic resonance imaging revealed contrast-enhancement of the signal for both facial nerves. He was administered prednisolone. After two weeks, the symptoms improved, and after one month, he completely recovered from facial diplegia. This is the first case in the literature in which the patient exhibited facial diplegia, a delayed complication, in scrub typhus. Facial diplegia should be considered a type of cranial nerve palsy that may occur as a delayed complication of scrub typhus.
Progressive Bulbar Palsy with Facial Diplegia and Proximal Weakness Diagnosed as Juvenile-Onset Myasthenia Gravis Rajesh Verma, Rajarshi Chakraborty, Pooja Tripathi Annals of Indian Academy of Neurology.2023; 26(4): 589. CrossRef
A Case of Ramsay-Hunt Syndrome with Dysphagia Treated by a Comprehensive Traditional Korean Medicine Regimen Including Pharmacopuncture and Herbal Medicine Geun-mo Kim, Hee-doh Kwon, So-hyun Pak, Ji-hong Park, Chang-min Shin, Hyun-Seob Park, Kyung-won Ha, Jong-Cheol Seo, Cheol-Hong Kim, Shin-young Kim, Hyun-Min Yoon Journal of Acupuncture Research.2024;[Epub] CrossRef
Background: The autophagy is the major route for lysosomal degradation of misfolded protein aggregates and oxidative cell components. We hypothesized that rapamycin (autophagy enhancer) would prolong the survival of motor neuron and suppress the disease progression in amyotrophic lateral sclerosis (ALS). Methods: A total of 24 transgenic mice harboring the human G93A mutated SOD1 gene were used. The clinical status involving rotarod test and survival, and biochemical study of ALS mice model were evaluated. Results: The onset of symptoms was significantly delayed in the rapamycin administration group compared with the control group. However, after the clinical symptom developed, the rapamycin exacerbated the disease progression and shortened the survival of ALS mice model, and apoptosis signals were up-regulated compared with control group. Conclusions: Even though further detailed studies on the relevancy between autophagy and ALS will be needed, our results revealed that the rapamycin administration was not effective for being novel promising therapeutic strategy in ALS transgenic mice and exacerbated the apoptosis.
Citations
Citations to this article as recorded by
Mechanism of motoneuronal and pyramidal cell death in amyotrophic lateral sclerosis and its potential therapeutic modulation Bernát Nógrádi, Dóra Nógrádi-Halmi, Barbara Erdélyi-Furka, Zalán Kádár, Tamás Csont, Renáta Gáspár Cell Death Discovery.2024;[Epub] CrossRef
Background: Bell’s palsy (BP) is the most common cause of unilateral lower motor facial palsy. Recurrent paralysis of the facial nerve is unusual and reported in only 7-8%. Methods: A total of 394 consecutive patients with acute BP patients were enrolled at Daegu Catholic University Hospital from July 2005 to September 2012. We classified the patients into two groups-single BP and recurrent BP-and compared them by patient characteristics, clinical features, MRI findings, electrophysiologic findings and prognosis. The degree of BP was graded according to the House and Brackmann facial nerve grading system. Results: Recurrent BP was observed in 31 (7.9%) patients. The number of recurrence was varied from 2 to 5. The recurrent BP (9.7%) had more incidence of family history and MRI enhancement than those of single BP (2.2%, p=0.047). The single BP (63.4%) had better recovery than recurrent BP (45.2%, p=0.045). Conclusions: The recurrent BP had more incidence of family history, MRI enhancement and poor prognosis than the single BP.
Citations
Citations to this article as recorded by
Characteristics and Treatment Methods of Bell’s Palsy in Patients Visiting Korean Medicine Hospitals From August 2018 to July 2021 Hyeon Kyu Choi, Min Ju Kim, Young Rok Lee, Hyun Ji Cha, Hyun Jin Jang, So Jeong Kim, Ju Hyun Jeon, Young Il Kim Journal of Acupuncture Research.2022; 39(2): 122. CrossRef
Correlation of Internal & External Factors with the Beginning Period of Improvement in Idiopathic Facial Paralysis※ Hee Jin Sung, Su Sie Lim, Hyun Young Choi, Eun Yong Lee, Jung Du Roh, Cham Kyul Lee The Acupuncture.2016; 33(1): 57. CrossRef
A Clinical Study on Children and Adolescents Who Visited the Hospital of Korean Medicine for 284-Peripheral Facial Palsy Ki Yeon Kang, Hye Lim Lee, Jae Kyung Han, Yun Hee Kim The Journal of Korean Oriental Pediatrics.2014; 28(4): 45. CrossRef
Background & Objectives :In cerebral palsy, spastic paraplegia is one of the most crippling motor manifestations. Reducing the spasticity may improve gait and decrease the incidence of lower-extremity deformities. The spasticity may result from abnormally increased afferent signals via dorsal roots onto interneurons and anterior horn and spreading of reflex activation to other muscle groups. To assess the influence of dorsal rhizotomy to spasticity, the authors analyzed five cerebral palsy patients with spastic paraplegia. Methods : The operation entailed and L1-2 laminectomy, ultrasonographic localization of conus medullaris and identification of lumbosacral dorsal roots. The innervation patterns of each dorsal root were examined by electromyography (EMG) responses to electrical stimulation. Tetanic stimulation was applied to individual rootlets of each root after reflex threshold was determined. the reflex responses were graded and rootlets producing high grade response were selected and cut. Short-term postoperative evaluations were performed. Results : Intraoperative EMG monitoring was satisfactorily performed in all five cases. One month after the operations, all patients showed greatly reduced spasticity which was measured by the instrumental gait analysis. Bilateral knn and ankle jerks were normalized and tip-toe gait with scissoring disappeared in all patients. Conclusion : Intraoperative EMG monitoring seems useful for the selective dorsal rhizotomy to reduce spasticity.
In clinical neurology various different electrophysiological tests are widely used to demonstrate the unsuspected malfunctioning in the nervous system and to monitor over time the clinical status of patients. In addition clinical neurologists and neurosurgeons take advantage of the intraoperative monitorings to increase the quality of neurosurgical operations in the posterior fossa, in the spinal cord, or in visual pathways. In the field of movement disorders, electrophysiological tests provide neurologists with making accurate differential diagnoses with useful therapeutic tests it could be possible for us to evaluate the types of blephalospasm, the extent of hemifacial spasm, the level of myoclonus, and the prime muscle of torticollis etc. Sometimes the myographic guidance may be critical for choosing the exact injecting site of botulinum toxin. These several decades various electroencephalographic and evoked potential tests had been utilized in the electrophysiological laboratories to understand the basic pathophysiology of myoclonus, spasticity and other central motor dysfunctions. It could be one of the breakthroughs in the area of behavorial neurology that the brain function can be mapped by the spontaneous or evoked electrical activities of nervous system since the movement related potentials (MRPs) had been studies for several decades. Various reflex tests such as masseter reflex, blink reflex, click evoked vestibulocollic reflex, facial reflex, stretch reflex, flexor reflex, H-reflex recovery curve, vestibulbar inhibition of H-reflex, reciprocal inhibition, recurrent or Renshaw reflex, Ib inhibition, cutaneous reflex have been also used to understand normal or abnormal physiology in movement disorders. Polysomnography, posturography and gait studies are also applied in clinical neurology in association with movement disorders which are useful in deciding the treatment regimen.
Transcranial magnetic stimulation is a non-invasive, painless diagnostic tool of nervous propagation as well as of motor cortex excitability in healthy subjects and in patients affected by several neurological disease ie, stroke, epilepsy and multiple sclerosis etc. Motor areas can be reliably mapped and short-and long-term 'plastic' changes of neural connections can be studied and monitored over time. Recent studies suggest a therapeutic role of repetitive magnetic stimulation in neurologic and psychiatric disorders.
Background and Purpose : Brainstem auditory evoked potentials(BAEPs) are responses of the brainstem by auditory stimulation. Vertebrobasilar transient ischemic attacks is the disease that occurs by insufficient circulation in the region of brainstem. The purpose of this study is to know the factors influencing the changes of BAEPs in vertebrobasilar transient ischemic attacks. Methods : The subject of study was 96 patients diagnosed as vertebrobasilar transient ischemic attacks. Patients were divided into two groups according to the BAEPs findings, age, sex, presence of hypertension, diabetes, hyperlipidemia, heart disease, neurologic findings, previous stroke, previous stroke, previous vertebrobasilar transient ischemic attacks, smoking and alcohol drinking, and time period between symptom onset and testing were compared. Results : There were no significant differences in age, sex, and presence of hypertension, diabetes, hyperlipidemia, heart disease, previous stroke history, previous vertebrobasilar transient ischemic attack, smoking, and alcohol drinking between two groups. The presence of abnormal neurologic findings in the first examination and time period between symptom onset and testing were significantly different between normal BAEPs group and abnormal BAEPs one(P < 005). Conclusions : The factors influencing the changes of BAEPs were presence of abnormal neurologic findings and time period between symptom onset and testing. These finding suggest that BAEPs test should be performed in acute stage of ischemic attack.
Backgrond : Bell's palsy(BP) is defined as an idiopathic peripheral facial paralysis of acute onset, accounting for more than 50% of all cases of facial parlysis. Different theories on the etiology of BP have been proposed. Herpes simplex virus-1(HSV) has been the most suspicious causative agent, but varicella zoster virus(VZV) also is suspected. Objectives : We evaluated the serological changes of IgG and IgM titer of HSV and VZV to know the causative agent of BP. Materials and Methods : Subjects consisted of 35 patients who developed acute idiopathic unilateral facial palsy(16 men and 19 women from 9 to 78 years old) within a week of onset. We took the serum of the acute and convalescent stages, respectively. Serum IgG and IgM titer of HSV and VZV were measured in acute and convalescent stages by EIA method. Results : Only the HSV IgG titer showed statistically significant elevation in the convalescent stage(p=0.0291). Others did not show any significant changes between the acute and convalescent stage. Conclusion : We concluded that HSV may be related to the causative agent of BP.
Although the etiology and pathogenesis of amyotrophic lateral sclerosis(ALS) in unknown, increasing evidence support a role autoimmune machanisms in motor neuron degeneration. The coexistence of immune disease in ALS supports that an altered immune system may contribute to disease pathogenesis. A 55-year-old woman was admitted to our department due to dysarthria and gait disturbance. On physical and neurologic examination, she showed thyroid enlargement, tongue atrophy, muscle weakness, fasciculation, and increased deep tendon reflex. The electrophysiological studies are compatible with motor neuron disease. Cytological findings of thyroid were compatible with hashimoto's thyroiditis. Thus, we report a case of ALS combined with Hashimoto's thyroiditis. And the simultaneous presentation with ALS and Hashimoto's thyroiditis led us to consider whether this was simply a chance association or not.
Background : Bell's palsy(BP) is defined as an idiopathic peripheral facial paralysis of sudden onset and account more than 50% of facial paralysis. It's etiology is unclear, but herpes simplex virus type-1 (HSV-1) has been the most suspicious causative agent of BP that over been studied. We evaluated the effect of add-on acyclovir in acute stages of BP. Methods : Subject consisted of 35 patients who developed acute within 10 days after onset of BP. Facial nerve function was assessed by the House-Brackman facial nerve grading scale and facial nerve conduction study including blink reflex. Follow-up evaluation were made 2 month after onset. Twenty of 35 patients were treated with combined therapy of acyclovir and prednisone. As a control group, 15 patients were treated with prednisone only. We compared the improvement of neurologic defects at recovery phase. Results : Compared with two groups, difference in grading scale at recovery phase is statistically significant(p<0.01). So, acyclovir-prednisone group showed a significant improvement in grading at recovery phase compared with prednisone group. Conclusion : We identified the benefit of add-on acyclovir in the acute stage of BP
Background : Backpack palsy was described in military personnel with shoulder girdle and proximal upper extremity symptoms, predominantly motor in nature related to the use of heavy backpack. Currently, backpack were used for sports, transpoting, school books and child carriers. We evaluated clinical and electrophysiological feature of backpack palsy. Methods : We included 11 patients with brachial plexopathy as a results of wearing a heavy backpack on long distance marches. All patients were done routine blood sampling, chest X-ray, C-spine X-ray and electrophysiological studies. Results : All patients were right handed person and were not as having a thoracic outlet syndrome. Sensory changes were main initial symptoms and major persistent symptoms were motor weakness. 9 patients(81.8%) were damaged the brachial plexus on non-dominant side, 1 patients was dominant and 1 patient was bilateral involvement. 10 patients(90.9%) were damaged to upper trunk of the brachial plexus by EMG findings. The prognosis was good, 10 patients(90.0%) were complete recovery during 8 weeks, 1 patient was developed reflex sympathetic dystrophy confirmed by 3-phase bone scan. Conclusions : Depression of the clavicle and costoclavicular space probably plays a certain role in pathogenic mechanism. The non-doinant side is more frequently affected, probably due to underdevelopment of the musculature in that side.
Objectives : Although the diagnosis of hereditary neuropathy with liability to pressure palsies(HNPP) in important for correct prognostic evaluation and genetic counseling, the diagnosis is frequently missed or delayed. Our main aim on undertaking this study was to characterized\ the electrodiagnostic features of HNPP. Material and Methods : Clinical, electrophysiologic and molecular studies were performed on Korean HNPP patients with 17P11.2 deletion. The results of eletrophysologic studies were compared with those of Charcot-Marie-Tooth disease type 1A (CMT1A) patients carrying 17p11.2 duplication. Results : Eight HNPP (50 motor, 39 sensory nerves) and six CMTIA (28 motor, 16 sensory nerves) patients were included. The slowing of sensory conduction in nearly all nerves and the distal accentuation of motor conduction abnormalities are the main features of background polyneuropathy in HNPP. In contrast to CMTIA, where severity of nerve conduction slowing was not different among nerve groups, HNPP sensory nerve conduction was more slowed in the median and ulnar nerves than in the sural nerve (p<0.01), and DML was more prolonged in the median nerve than in the other motor nerves (p<0.01). TLIs were significantly lower in HNPP than in the normal control and CMTIA patients for the median and ulnar nerves (p<0.01), and were also significantly reduced for the peroneal nerve (p<0.05) compared with those of the normal controls. Conclusion : The distribution and severity of the background electrophysiologic abnormalities are closely related to the topography of common entrapment or compression sites, which suggests the possible pathogenetic role of subclinical pressure injury at these sites in the development of the distinct background polyneuropathy in HNPP.
Background Electrophysiologic study accurately predicts the degree of degenerated motor axons but cannot giveprecise information on the type of injury that occurred in Bell
B a c k g r o u n d s: The pathway of the sural nerve (SN) is variable, but usually divided into medial and lateral suralbranches joining the posterior tibial nerve (PTN) and the peroneal nerve (PN). The sural nerve may be affected by PNpalsy. The frequency or the severity of SN involvement in peroneal palsy is not known. The purpose of the study is toinvestigate the frequency and the severity of the SN involvement by the peroneal nerve palsy.Methods: Total 85 patients were included with peroneal palsy. Amplitudes of distal peroneal, sural, and superficialperoneal nerves (SPN) were compared between normal and paralyzed sides. The frequency and severity of SN involvementby peroneal palsy were investigated.Results: Mean age was 48.4
Loud click or tone burst sound can activate vestibular receptor and evoke reflex changes in tonic electromyographicactivity within the stenocleidomastoid muscles. This reflex is assumed to originate in the saccule, the afferent pathwaysbeing the inferior vestibular nerve, and the efferent pathways the vestibulospinal tract. Averaging these muscularresponses allows vestibular evoked myogenic potentials (VEMP) to be obtained. The earliest response ipsilateral to aloud click, p13n23, is dependent upon vestibular activation, specifically saccular afferents. These new techniques arebeginning to be applied clinically in the patient of vestibular neuritis, Meniere
Two hemiplegic cerebral palsy patients were studied to investigate the cortical mechanisms underlying preserved somatosensory capacity, using functional MRI(fMRI). Tactile stimulation was performed by brushing of palm, during fMRI study. By the affected hand stimulation, contralateral primary somatosensory cortex was activated in patient 1 and cortical area anterior to the lesion site was activated in patient 2. We suggest that reorganization of the somatosensory cortex after brain injury can be induced by recruitment of undamaged areas adjacent to lesion site.
Background There is no currently effective treatment for amyotrophic lateral sclerosis (ALS), although this disorder is a progressive neurodegenerative disease resulting in death within several years. Because recent evidence suggests that homocysteine (HC) is highly related to neurodegenerative disorders with aging, we tried to elucidate the effects of multi-vitamin therapy on G93A SOD1 transgenic mice.Methods: We treated this murine model of ALS with multi-vitamin (folic acid 1.97 mg/day, pyridoxine 0.98 mg/day, cyanocobalamin 0.1 mg/day) from 45 days of age, per oral. We performed the rotarod test from postnatal 10th week,weekly.Results: We found that multi-vitamin reinforcement significantly prolonged average lifespan and delayed disease onset with improvement of motor performance. However, it did not significantly slow disease progression and statistical differences of weight loss were not observed between in transgenic mice and controls.Conclusions: These results suggest that multi-vitamin can be a potent therapeutic strategy for familial forms of ALS.
Background It has been proposed that proprioceptive input can modulate neural excitability in both primary motor cortices (M1) simultaneously, although direct evidence for this is still lacking. Previous studies showed that proprioceptive accuracy of one hand is reduced after the application of one-Hz repetitive transcranial magnetic stimulation (rTMS) for 15 minutes over the contralateral somatosensory cortex. The aim of this study was to investigate the effect of rTMSinduced central proprioceptive deafferentation to excitability of both M1 as reflected in ipsilateral and contralateral motor evoked potentials (MEP). Methods: MEPs of both abductor pollicis bravis (APB) muscles were recorded using single-pulse TMS over right M1 in seven healthy subjects. Immediately after one-Hz rTMS was applied for 15 minutes over the right somatosensory cortex, the MEP measurement was repeated. The proprioceptive function of the left thumb was assessed, before and after rTMS, using a position-matching task. Results: There was an increase in ipsilateral MEP after the rTMS: whereas no MEPs were recorded on the ipsilateral hand before the rTMS, MEPs were recorded in both ipsilateral and contralateral hand in three of seven subjects. At the same time, the mean log amplitude was reduced and the mean latency was prolonged in the contralateral MEP. Conclusions: rTMS-induced central proprioceptive deafferentation reduces the MEP generation in the contralateral hand, and fascilitates that in the ipsilateral hand. A further study with a larger sample seems warranted to confirm this finding and to elucidate the neurophysiology underlying it.
A 69 year-old woman was admitted with sudden left facial weakness. She had no other neurologic deficit, except for left peripheral type facial palsy. She had a presumptive diagnosis of Bell
We report a case of chiasmal optic neuritis in a patient who had been diagnosed as multiple sclerosis, and was presented with bitemporal hemianopsia. The brain MRI revealed a high signal lesion with focal enhancement in optic chiasm, and the visual evoked potential functionally supported it. This is the first case of chiasmal optic neuritis in multiple sclerosis with temporally and spatially disseminated lesions.
Background: Bell's palsy (BP) is a self-limited rapid onset facial palsy that is non-life-threatening and has a generally favorable prognosis. Facial paralysis can be caused by numerous conditions, all of which should be excluded before thediagnosis of BP is reached. The etiopathogenesis and clinical course of BP are uncertain. So we analyzed the epidemiology and clinical course of BP patients.
Methods: The subjects include 100 cases of BP examined during the period of 18 months. Careful clinical history, neurologic examinations, laboratory tests, electrophysiologic studies, and brain imaging were performed. Follow-up examinations were done once a week during the first month and subsequently once a month until normal function was restored or for up to 3 months. Facial nerve function was assessed by House-Brackman (HB) facial nerve grading scale and electrophysiologic studies. Results: Except 13 recurrent BP patients, we analyzed 87 BP patients. Forty-four (50.6%) were men and 43(49.4%) were women and the mean age was 51.0(
Intraoperative neuromonitoring (INM) is well known to be useful method to reduce intraoperative complications during the surgery of nervous system lesions. Evoked potentials are most commonly used among the electrophysiological tests. Brainstem auditory evoked potentials are for detecting the problems along the auditory pathways including the eighth cranial nerve and brainstem. Somatosensory evoked potentials are applied for preventing the spinal cord lesions. The INM is affected by many factors. In order to perform an optimal INM, the confounding factors including technical, anesthetical, and individual factors should be kept well under control. INM has frequent electrophysiologic changes during the surgery and it might be helpful to keep one
Since the majority of cases with unilateral peripheral facial palsy are idiopathic, radiological studies such as CT or MRI are not usually recommended for further evaluation. We report a patient with peripheral facial palsy caused by minor salivary gland tumor which was demonstrated by appropriate imaging study.
The etiology of intractable hiccups is most commonly idiopathic. However, they are occasionally associated with some underlying disorders including gastro-esophageal reflux disease. There are a few previous reports describing the association of intractable hiccups with high dose corticosteroid. We experienced an unusual case of intractable hiccups following a high dose intravenous methylprednisolone therapy in a patient with right third nerve palsy. Since methylprednisolone is commonly used in various neurological problems, physicians should be aware of its possible side effect including intractable hiccups.
Collet-Sicard Syndrome is one of the variant of the jugular foramen syndromes in which the last four cranial nervesare involved whereas the sympathetic plexus is spared. The possible causes of these multiple lower cranial nerve palsyare variable, including metastasis of systemic malignancy to the base of skull, primary tumor of head and neck, vascularcomplication, trauma and so on. We experienced two men visited to our clinic with symptoms of headache, hoarsness,swallowing difficulty and showed the evidence of cranial nerve palsy on neurologic examination. Magnetic resonanceimaging and computed tomography demonstrated oropharyngeal and hypopharyngeal tumor and electrodiagnostic study supported the diagnosis.
Various electrophysiological tests have provided a large body of valuable information on neuronal responses to a presentedstimulus. The special and general somatic sensory pathways are main targets of evoked potentials. Two types of evokedpotentials, exogenous and endogenous, are commonly used. Exogenous evoked potentials of general and special somatic sensorysystems will be reviewed. One of general somatic sensory functional pathways, proprioception, can be evaluated by generalsomatosensory evoked potentials with electrical stimulation on nerves. The special somatosensory functional pathways,including vision, and audition, can be evaluated by visual evoked potentials and auditory evoked potentials. Also laser-evokedpotentials are newly developed for pain pathway, including lateral spinothalamic pathway, and vestibular myogenic evokedpotentials for sacculocollic pathways. The evoked potentials of sensory system have maximal clinical utility in evaluatingfunctional deficits along the sensory pathways. They are used for evaluating comatose patients, hysterical patients, prematureinfants, patients with suspected demyelinating diseases or neoplasms, and research. We discuss the neurophysiologic testsof sensory systems in views of practical points. The organized evaluation of sensory electrophysiologic tests can be helpfulin detecting and estimating the abnormalities in neurological diseases.
Neuro-ophthalmological findings are common and occasionally prominent features in movement disorders. Accordingly,careful evaluation of the ocular motor functions may provide valuable information in early detection of the diseases andmonitoring of the progression. Furthermore, accurate assessment of the abnormal ocular motor findings aids in understandingthe pathophysiology and mechanisms of the movement disorders, and in their differential diagnosis. Ocular motility examinationshould include bedside evaluation and laboratory recording of the fixational abnormalities, saccades, smooth pursuit, thevestibulo-ocular reflex, optokinetic nystagmus, and vergence eye movements. In this review, we will discuss various ocularmotor findings in ataxia and parkinsonian syndromes, and hyperkinetic movement disorders.
Background Miller-Fisher syndrome (MFS) is characterized by the clinical triad of ophthalmoplegia, ataxia, and areflexia,and is considered a variant form of Guillain-Barre syndrome. Although some cases of delayed-onset facial palsy in MFShave been reported, the characteristics of this facial palsy are poorly described in the literature. Methods: Between 2007and 2010, six patients with MFS were seen at our hospital. Delayed facial palsy, defined as a facial palsy that developedwhile the other symptoms of MFS began to improve following intravenous immunoglobulin treatment, was confirmed in fourpatients. The clinical and electrophysiological characteristics of delayed facial palsy in MFS, as observed in these patients,are described here. Results: Four patients with delayed-onset facial palsy were included. Delayed facial palsy developed 8-16days after initial symptom onset (5-9 days after treatment). Unilateral facial palsy occurred in three patients and asymmetricfacial diplegia in one patient. The House-Brackmann score of facial palsy was grade III in one patient, IV in two patients,and V in one patient. None of the patients complained of posterior auricular pain. Facial nerve conduction studies revealednormal amplitude in all four patients. The blink reflex showed abnormal prolongation in two patients and the absence ofaction potential formation in two patients. Facial palsy resolved completely in all four patients within 3 months. Conclusions:Delayed facial palsy is a frequent symptom in MFS and resolves completely without additional treatment. Thus, standardtreatment and patient reassurance are sufficient in most cases.
First
Prev
