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Neurological symptomatology is a crucial component of neurological expertise. The committee for fostering board‐certified neurologists in the Japanese Society of Neurology (JSN) has hosted an educational activity for residents before the board examination, "The seminar for fostering board‐certified neurologists" since 2004. In particular, the autumn seminar has been characterized by small group hands‐on of neurological examinations and the evaluations of higher brain function. Besides this, hands‐on seminar of neurological examinations by regional branches has been promoted by the JSN. In the Kanto Ko‐shin‐etsu branch, "The first hands‐on seminar of neurological examinations" started in 2023 after a 3‐year‐suspension due to COVID‐19. The most important educational activities in neuromuscular electrodiagnosis (EDx) is the "Neuromuscular diagnostics seminar" hosted since 2004 by the Japanese Society of Clinical Neurophysiology (JSCN). The majority of tutors and participants are neurologists. This seminar is also characterized by small‐group, hands‐on workshops. We have also run the overseas seminar, "Tokyo Super EMG hands‐on," since 2013. These have undoubtedly contributed to enhancing the level of neuromuscular electrodiagnosis not only in Japan but also in other Asian countries. I have conducted studies on neurological symptomatology and neuromuscular electrodiagnosis, which are directly linked to enhancing clinical practice of neurologists through educational activities such as review articles or lectures. Due to the fact that symptomatology is crucial in neurological expertise, neurology is a basic specialty around the world except in Japan. In 2018, the JSN decided to aim to make neurology a basic specialty and continues to make efforts to attain this goal. [ABSTRACT FROM AUTHOR]

Background: As the human population ages, there is an urgent need to find new fall prevention strategies that differ from the conventional strategy of improving physical motor functions. Therefore, this study aimed to investigate the mechanism of falling during a dual task based on eye movements and frontal blood flow in the elderly. Methods: Thirteen healthy elderly women participants performed the following tasks while walking on the spot: stepping at a normal walking speed (single task), stepping at a normal walking speed while solving mathematical problems (dual task), and stepping at a normal walking speed while looking carefully at an image in front of them (control task). Eye movements, stepping state (number of steps and toe height), and frontal blood flow of the participants were measured. Results: The participants’ eye movements were significantly greater during the dual task than during the single and control tasks. However, the number of steps was not significantly different while performing the dual and single tasks. Toe height was significantly lower during the dual task than during the single task. Finally, frontal blood flow increased while performing the dual task compared with while the single task. Conclusion: This study clarified the mechanism by which fall occurs in elderly participants. Eye movements increased during dual task walking; however, the additional task involving “thinking” required focus, the visual search became sparse, and the toe height was reduced. These factors increased the risk of “stumbling,” which is considered the primary mechanism of falls. [ABSTRACT FROM AUTHOR]

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a most common chronic immune-mediated demyelinating neuropathy, and includes a number of clinical subtypes. The major phenotype is "typical CIDP", which is characterized by symmetric polyneuropathy and "proximal and distal" muscle weakness. During the historical changes in the concept of CIDP, multifocal motor neuropathy, anti-myelin-associated glycoprotein (MAG) neuropathy, and autoimmune nodopathy have been excluded. Currently CIDP is considered as a syndrome including typical CIDP and CIDP variant such as distal CIDP and multifocal CIDP. In 2021, the international guideline of diagnosis and treatment for CIDP, European Academy of Neurology (EAN)/Peripheral Nerve Society (PNS) Guideline, was published. This review article introduces the putline of the guideline with medical-social situation in Japan. The diagnosis of CIDP is based on (1) phenotype of typical CIDP or variant, (2) electrophysiologic evidence of peripheral nerve demyelination, and (3) exclusion criteria. The first-line treatments are corticosteroids or immunoglobulin therapy, and plasma exchange should be considered if the 2 treatments were not effective sufficiently. This guideline recommends intravenous or subcutaneous immunoglobulin as a maintenance therapy, and suggests other immune-suppressive agents. In the near future, new treatment with biologics, such as monoclonal antibodies against neonatal Fc receptors, complements, and CD19/20 will be approved.

Objective: Approximately 15%-20% of patients with Guillain-Barré syndrome (GBS) are unable to walk independently at 6 months from the onset of neurological symptom. The modified Erasmus GBS outcome score (mEGOS) has been reported as a prognostic tool.Herein we investigated the association between a poor outcome, inability to walk independently at 6 months and presence of antiganglioside antibodies.Methods: The clinical and serological data of 177 patients with GBS were retrospectively collected in Japan to assess the associations between a poor outcome and serum IgG antibodies against each ganglioside (GM1, GD1a, GalNAc-GD1a, GQ1b and GT1a). In addition, we investigated whether the combination of mEGOS and serum IgG antibodies against gangliosides is useful in predicting a poor outcome.Results: The patients with IgG anti-GD1a antibodies more frequently showed poor outcomes than those without these antibodies (9 (36%) of 25 vs 8 (6%) of 127 patients, p<0.001). Particularly, 80% showed a poor outcome when they had both serum IgG anti-GD1a antibody and a high mEGOS of ≥10 on day 7 of admission.Conclusions: The combination of serum IgG anti-GD1a antibodies and a high mEGOS could help in making a more accurate prognosis of patients than mEGOS alone, especially for predicting poor outcomes. [ABSTRACT FROM AUTHOR]

Background: Various pathological elbow lesions are often complicated with ulnar neuropathy at the elbow (UNE), although the precise pathology, incidence, and clinical and neurological features of these lesions have not been identified. We therefore investigated elbow pathology and neurological severity in Japanese patients with UNE.Methods: The medical records of 457 Japanese UNE patients who were surgically treated among 6 hospitals were retrospectively examined. Eligible patients had UNE diagnosed by physical findings and nerve conduction studies according to the criteria of the American Association of Electrodiagnostic Medicine. The elbows were analyzed with regard to age, gender, occupation, pathology at the elbow, and severity of nerve palsy.Results: A total of 398 patients with 413 UNE elbows of a mean age of 63 years (range: 15-87) met the inclusion criteria. UNE elbows were predominantly in male patients (69.0%). Overall, 310 elbows (75.1%) had 1 or more elbow lesions: 238 elbows (76.8%) had a single lesion and 72 elbows (23.3%) had 2 or more lesions. The most common lesion was primary elbow osteoarthritis (EOA) occurring in 54.5% of elbows, followed next by medial elbow ganglion in 8.5% and cubitus valgus in 6.5%. Most elbows with medial elbow ganglion or cubitus valgus were associated with EOA. Entrapment sites were at the cubital tunnel in 84.5%-91.3% of UNE elbows, regardless of an association with elbow lesion. The incidence of McGowan grade III lesion was 50.8% in elbows with primary EOA, which was higher than the 35.0% in elbows with no lesion.Conclusions: This study revealed that UNE had various isolated or combined elbow lesions. In Japanese UNE, primary or secondary EOA was found in 62.2% of cases and severe motor weakness was noted in 47.2%. The incidences of EOA and severe ulnar nerve palsy in the Japanese UNE are higher than those in Caucasians.Level Of Evidence: Level IV; Prognostic-Investigating the effect of a patient characteristic on the outcome of a disease; Case series. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to develop a quantitative evaluation method of interference patterns on needle electromyography that is easy to apply in clinical use and to examine its usefulness. Diagnostic electrophysiological assessments are important for physiatrists, and correct diagnosis and assessment are essential for proper rehabilitation. Design: A total of 112 maximum interference patterns of upper extremity muscles suspected of being affected by neuropathy were quantitatively evaluated based on the parameters of integration values, mean amplitudes, the number of peaks, and activity. "Activity" was defined as the sum of the time during which myoelectric signals were recorded during 1 sec with maximum voluntary contraction, and it was expressed as a percentage. The relationships of the previous parameters with spontaneous pathological potentials and polyphasic motor unit potentials were examined. Results: The area under the curve of the receiver operating characteristic curve for the diagnosis of neuropathy was the highest using activity (0.917). The integral value and mean amplitude were useful for the diagnosis of cases with chronic neuropathy showing slightly decreased interference patterns. Conclusions: The quantitative evaluation of the maximal contraction interference pattern in this study was useful for the diagnosis of neuropathy. [ABSTRACT FROM AUTHOR]

Background: This retrospective study was designed to investigate prognostic factors for postoperative outcomes for cubital tunnel syndrome (CubTS) using multiple logistic regression analysis with a large number of patients.Methods: Eighty-three patients with CubTS who underwent surgeries were enrolled. The following potential prognostic factors for disease severity were selected according to previous reports: sex, age, type of surgery, disease duration, body mass index, cervical lesion, presence of diabetes mellitus, Workers' Compensation status, preoperative severity, and preoperative electrodiagnostic testing. Postoperative severity of disease was assessed 2 years after surgery by Messina's criteria which is an outcome measure specifically for CubTS. Bivariate analysis was performed to select candidate prognostic factors for multiple linear regression analyses. Multiple logistic regression analysis was conducted to identify the association between postoperative severity and selected prognostic factors.Results: Both bivariate and multiple linear regression analysis revealed only preoperative severity as an independent risk factor for poor prognosis, while other factors did not show any significant association.Conclusions: Although conflicting results exist regarding prognosis of CubTS, this study supports evidence from previous studies and concludes early surgical intervention portends the most favorable prognosis. [ABSTRACT FROM AUTHOR]

Objective: To determine the current perception thresholds (CPTs) for arm and mental foramen areas to enable a quantitative evaluation of the effectiveness of acupuncture treatment. Methods: Ninety-eight volunteers enrolled as participants and were randomly assigned to one of three groups: an acupuncture group (34 subjects); a sham acupuncture group (32 subjects) and a waiting group (32 subjects). CPTs for the arm and mental foramen areas were determined before and after acupuncture at LI4 Hegu of the left hand. A Neurometer CPT was used to evaluate the perception threshold at the homolateral mental foramen and arm. For further exploration, thresholds of homolateral and contralateral mental foramina were determined before and after acupuncture in a subgroup of 13 participants in the acupuncture group. Results: Acupuncture at LI4 increased the perception thresholds of the left mental foramen in the acupuncture group significantly (p<0.01). The increases were significantly greater than in the control group for all frequencies, and significantly greater than sham acupuncture for 250 Hz and 5 Hz. In the subgroup, only the CPTs at 5 Hz increased significantly for the contralateral mental foramen. Conclusions: Acupuncture at LI4 increases the perception threshold in the mandibular area, but not in the arm. This finding is probably related to the analgesic effect of acupuncture. [ABSTRACT FROM AUTHOR]

WHAT IS THE EXTENT AND NATURE, CLINICALLY AND ELECTROPHYSIOLOGICALLY, of peripheral nerve involvement in primary systemic AL amyloidosis? To address these questions, a retrospective review was undertaken of 43 such patients, previously untreated, admitted between April 2002 and June 2008 to the Department of Medicine, Shinshu University School of Medicine, Matsumoto, Japan. Diagnosis was based on tissue biopsy confirmation of amyloid deposition using Congo red and immunohistochemical staining. Records reviewed included the neurological examination, electrodiagnostic studies, past medical history, and blood and urine studies. Statistical analysis was provided by Student's t-test and Mann--Whitney's U test with P < 0.05 considered statistically significant. Neuropathic involvement, either mononeuropathy, polyneuropathy, or autonomic neuropathy, was evident in 15 patients (34.9%), including nine men and six women, with a mean age of 57.9 years and a mean disease duration of 14.7 months. Polyneuropathy was diagnosed in 11; in two of these it was the presenting symptom. Bilateral carpal tunnel syndrome was present in four, including one with polyneuropathy. Autonomic symptoms, encompassing orthostatic hypotension, hypohydrosis, impotence, urinary incontinence, and alternating diarrhea and constipation, were present in eight, only one of whom had neither polyneuropathy nor carpal tunnel syndrome. In all, sensory symptoms were predominant, with muscle weakness in the distal legs present in only three elderly patients. None had cranial nerve involvement. Electrodiagnostically, the polyneuropathy was predominantly axonal in nature, with decreased motor and sensory amplitudes but only minimal prolongation of terminal motor latencies and mild slowing of motor and sensory nerve conduction velocities compared to normal controls. Neuropathy is common in primary systemic AL amyloidosis and resembles that seen with the late-age-onset transthyretintype of familial amyloid polyneuropathy. [ABSTRACT FROM AUTHOR]

Objective: The duration of the distal compound muscle action potential (DCMAP) is a useful index to detect demyelination in the distal nerve segments. However in published electrodiagnostic criteria for chronic inflammatory demyelinating polyneuropathy (CIDP), the cut-off values of DCMAP duration are defined using an EMG low frequency filter of only 20 Hz. We aimed to provide widely-available reference data using several low cut filters., Methods: In 13 Japanese and European tertiary centers, DCMAP duration data using 2, 5, 10, and 20 Hz low frequency filters were prospectively collected from 147 normal controls, 59 patients with typical CIDP, and 100 with diabetic polyneuropathy. Optimal cut-off values were calculated with receiver-operating characteristic curves, offering 100% specificity versus normal controls., Results: The higher low frequency filter was associated with significantly shorter DCMAP duration in all groups. For CIDP diagnosis, the calculated cut-off values had a sensitivity ranging from 51% to 66%, and a specificity versus diabetic neuropathy from 96% to 98%., Conclusions: Our results show that DCMAP duration is largely dependent on low frequency filter settings, but is a useful index for CIDP diagnosis when the cut-off values are properly determined at each filter setting., Significance: Our data provide the systematic reference values of DCMAP duration for CIDP diagnosis available for most EMG laboratories., (Copyright © 2014 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.)

Objective: Guillain-Barré Syndrome (GBS) is classified into the two major subtypes; acute inflammatory demyelinating polyneuropathy (AIDP) and acute motor axonal neuropathy (AMAN). Previous studies have suggested that AIDP is predominant and AMAN is rare in Western countries, whereas AMAN is not always uncommon in East Asia. We aimed to clarify the incidence of the subtypes of GBS in Japan., Methods: We performed a prospective multicentre survey over 3 years (2007-2010). Clinical and electrophysiological findings were collected from 184 patients with GBS in 23 tertiary neurology institutes. Anti-ganglioside antibodies were measured by ELISA. We also surveyed the incidence of Fisher syndrome (FS)., Results: By electrodiagnostic criteria of Ho et al, patients were classified as having AIDP (40%), or AMAN (22%), or unclassified (38%). Anti-GM1 IgG antibodies were found for 47% of AMAN patients, and 18% of AIDP patients (p<0.001). There were no specific regional trends of the electrodiagnosis and anti-GM1 positivity. During the same study period, 79 patients with FS were identified; the percentage of FS cases out of all cases (FS/(GBS+FS)) was 26%., Conclusions: The frequency of GBS patients with the electrodiagnosis of AMAN by single nerve conduction studies is approximately 20% in Japan, and the AMAN pattern is closely associated with anti-GM1 antibodies. The incidence of FS appears to be much higher in Japan than in Western countries., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Objective: To comprehensively investigate the relationship between antibodies to single glycolipids and their complexes and Guillain-Barré syndrome subtypes and clinical features., Methods: In acute sera from 199 patients with Guillain-Barré syndrome, immunoglobulin G (IgG) antibodies to glycolipids and ganglioside complexes were tested using ELISA against individual antigens from single glycolipids including gangliosides (LM1, GM1, GM1b, GD1a, GalNAc-GD1a, GD1b, GT1a, GT1b, GQ1b) and a neutral glycolipid, asialo-GM1 (GA1), and antigens from the combination of 2 different glycolipids. Based on serial nerve conduction studies, the electrodiagnoses were as follows: 69 demyelinating subtype, 85 axonal subtypes, and 45 unclassified., Results: Significant associations were detected between acute motor axonal neuropathy subtype and IgG antibodies to GM1, GalNAc-GD1a, GA1, or LM1/GA1 complex. Reversible conduction failure was significantly associated with IgG antibodies to GM1, GalNAc-GD1a, GD1b, or complex of LM1/GA1. No significant association was demonstrated between acute inflammatory demyelinating polyneuropathy and any of the glycolipids or ganglioside complexes. Anti-ganglioside complex antibodies alone were detected in 7 patients (5 axonal subtype)., Conclusions: The current study demonstrates that antibodies to single glycolipids and ganglioside complexes are associated with acute motor axonal neuropathy or acute motor conduction block neuropathy but not acute inflammatory demyelinating polyneuropathy., Classification of Evidence: This study provides Class II evidence that antibodies to glycolipids are increased in patients with acute motor axonal neuropathy and acute motor conduction block neuropathy but not acute inflammatory demyelinating polyneuropathy., (© 2014 American Academy of Neurology.)

Several studies have revealed that stress after catastrophic disasters can trigger cardiovascular events, however, little is known about its association with the occurrence of heart failure in past earthquakes. The objective of the present study was to determine whether the Great East Japan Earthquake on March 11, 2011, increased the incidence of worsening heart failure in chronic heart failure (CHF) patients with implantable devices. Furthermore, we examined whether intrathoracic impedance using remote monitoring was effective for the management of CHF.We enrolled 44 CHF patients (32 males, mean age 63 ± 12 years) with implantable devices that can check intrathoracic impedance using remote monitoring. We defined the worsening heart failure as accumulated impedance under reference impedance exceeding 60 ohms-days (fluid index threshold), and compared the incidence of worsening heart failure and arrhythmic events 30 days before and after March 11.Within the 30 days after March 11, 10 patients exceeded the threshold compared with only 2 patients in the preceding 30 days (P < 0.05). Although 9 patients using remote monitoring among the 10 patients with threshold crossings were not hospitalized, one patient without the system was hospitalized due to acute decompensated heart failure. On the contrary, arrhythmic events did not change between before and after March 11.Our results suggest that earthquake-induced stress causes an increased risk of worsening heart failure without changes in arrhythmia. Furthermore, intrathoracic impedance using remote monitoring may be a useful tool for the management of CHF in catastrophic disasters.

Objective: The aim of this study was to report a series of Japanese patients with neuropathic symptoms following HCV infection., Patients and Methods: Fifteen patients with neuropathic symptoms and HCV infection were studied retrospectively (neuropathy group). We evaluated clinical and electrophysiologic findings. As a control group, we investigated prospectively 11 patients with chronic HCV hepatitis without neuropathic symptoms., Results: In the neuropathy group, the peripheral neuropathy was a multiple mononeuropathy (MM) in 8 patients, a polyneuropathy in 4 patients, a single cranial neuropathy in 2 patients, and a cervical radiculopathy in one patient. Five patients with MM had relapsing symptoms. Two patients showed a progression of neurologic symptoms following varicella zoster virus infection. Mixed cryoglobulinemia was noted in 4 of 13 tested patients. Circulating immunocomplexes were detected in 3 of 10 tested patients, and low complement (C3, C4, or CH50) levels were noted in 10 of 13 tested patients. Nerve conduction study (NCS) showed abnormal findings in 10 of 13 investigated patients. In the control group, only the frequency of low CH50 was significantly lower than that in the neuropathy group. Abnormal findings of NCS were found in 3 of 11 patients., Conclusion: We showed the presence of various types of neuropathies in patients with HCV infection. Our results suggest that relapsing MM is common in HCV positive neuropathy with or without cryoglobulinemia, and that the virus may modulate neurologic manifestations of other viral infections. Subclinical neuropathy may be present in some patients with HCV infection without neurologic symptoms.

To clarify the relations of the axonal form of Guillain-Barré syndrome (GBS) to anti-ganglioside antibodies and Campylobacter jejuni infection, 86 consecutive Japanese GBS patients were studied. Electrodiagnostic criteria showed acute inflammatory demyelinating polyneuropathy in 36% of the patients and acute motor axonal neuropathy (AMAN) in 38%. Frequent anti-ganglioside antibodies were of the IgG class and against GM1 (40%), GD1a (30%), GalNAc-GD1a (17%), and GD1b (21%). Identified infections were C. jejuni (23%), cytomegalovirus (10%), Mycoplasma pneumoniae (6%), and Epstein-Barr virus (3%). There was a strong association between AMAN and IgG antibodies against GM1, GD1a, GalNAc-GD1a, or GD1b. Almost all the patients with at least one of these antibodies had the AMAN pattern or rapid resolution of conduction slowing/block possibly because of early-reversible changes on the axolemma. C. jejuni infection was frequently associated with AMAN or anti-ganglioside antibodies, but more than half of the patients with AMAN or anti-ganglioside antibodies were C. jejuni-negative. These findings suggest that the three phenomena "axonal dysfunctions (AMAN or early-reversible conduction failure)," "IgG antibodies against GM1, GD1a, GalNAc-GD1a, or GD1b," and "C. jejuni infection" are closely associated but that microorganisms other than C. jejuni frequently trigger an anti-ganglioside response and elicit axonal GBS.

Traditional univariate comparisons of nerve conduction data against standard norms may produce conflicting estimates of the presence or absence of a diabetic neuropathy, depending upon the data obtained and the specific nerves sampled. Alternatively, a multivariate analytic approach, using discriminant functions, provides a useful single measure of the degree of neuropathy determined as a weighted combination of the available data. The weights are derived from the linear discriminant function, which maximizes statistical separation of diabetic and nondiabetic subject groups. In this study, 12 electrophysiologic attributes are used to generate a single discriminant function that clearly separates diabetic from nondiabetic subjects and is interpretable as a neuropathic index. Each individual's index of diabetic neuropathy (I) can be quantified as follows: (Formula: see text) where Ai is the original electrophysiologic attribute (i = 12), ai is the coefficient for each attribute that defines the discriminant function and C is a constant specific for that function. For the first time, the degree of diabetic neuropathy can thus be quantified for purposes of comparison and correlation with other quantifiable clinical/somatic measures of diabetes. The index allows for a higher percentage of type II diabetic patients to be classified as neuropathic than previously described and enables determination of degree of neuropathy is affected individuals by an interpolative method.