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Background and purpose: Spinal cord infarction (SCI) is difficult to diagnosis using MRI findings. We aimed to suggest the optimal timing of MRI studies for diagnosing SCI. Materials and methods: This retrospective study was approved by our institutional review board. The requirement for informed consent was waived. MRI scans of SCI patients diagnosed between January 2015 and August 2019 were enrolled in the SCI group and subdivided according to the interval between symptom onset and time of MRI scan (A, within 6 h; B, 6–12 hours; C, 12–24 hours; D, 24–72 hours; E, 3–7 days). Three radiologists analyzed the T2WI scans and evaluated the confidence level of diagnosing SCI using a five-point Likert scale: 1, certainly not; 2, probably not; 3, equivocal; 4, probably yes; 5, certainly yes. Scores of 4 and 5 were defined as "T2WI-positive SCI" and scores of 1–3 were defined as "T2WI-negative SCI". Results: The SCI group included 58 MRI scans of 34 patients (mean age, 60.6 ± 14.0 years; 18 women). The T2WI positivity rate was 72.4% (42/58). In contrast to the other subgroups, subgroup A included fewer cases of T2WI-positive SCI (1/4, 25%) than T2WI-negative SCI. A confidence score of 5 was the most common in subgroup D (4/27, 14.8%). Among the 12 patients who underwent MRI studies more than twice, confidence scores increased with time. Conclusion: In patients with suspected SCI showing equivocal initial MRI findings, follow-up MRI studies are helpful, especially when performed between 24 and 72 hours after symptom onset. [ABSTRACT FROM AUTHOR]

A demand for intraoperative neurophysiological monitoring (IONM) during various neurosurgical procedures is increasing rapidly in Asian-Oceanian region. Therefore, IONM- related local organizations have been established in several countries and doing their academic activities in this field. Also, Asian-Oceanian Society of Intraoperative Neurophysiology (AOSIN) was first established in 2018 for the purpose of education and dissemination of knowledge of IONM in this region, and has held its annual congress since then. This talk will be specifically focused on a review of the current status of IONM in this region and visions of AOSIN. Key Words: intraoperative neurophysiological monitoring (IONM), Asia-Oceania, Asian- Oceanian Society of Intraoperative Neurophysiology (AOSIN). [ABSTRACT FROM AUTHOR]

There are two main methodologies which can be used to assess the functional integrity of nervous system during intraoperative neurophysiological monitoring (IONM). Monitoring provides continuous real-time information about the functional integrity of the nervous tissue, whereas mapping provides rapid anatomical identification and localization of neural structures. Mapping of the primary motor cortex and subcortical corticospinal tract (CST) can be performed with direct cortical and subcortical electrical stimulation with a hand-held probe. Mapping of the central sulcus can be achieved by using phase reversal technique of somatosensory evoked potentials (SEP). This talk will be specifically focused on basic principles and application of these mapping methodologies and their usefulness mainly in brain tumor surgeries. Key Words: intraoperative neurophysiological monitoring (IONM), cortical mapping, subcortical mapping, central sulcus mapping [ABSTRACT FROM AUTHOR]

Neurosurgery in the brainstem is one of the most challenging procedures and requires higher level of intraoperative neurophysiological monitoring (IONM) methodologies to prevent severe postoperative neurological deficits. Some of them are specialized for the monitoring of the functional integrity of the brainstem during surgery. Among these, this talk will be specifically focused on IONM of the corticobulbar motor evoked potential (CoMEP) and brainstem reflexes. CoMEP can monitor functional integrity of the corticobulbar motor pathway continuously from the motor cortex to the cranial nerves. Also, brainstem reflexes can be reliable methodologies to monitor neural structures involved in brainstem reflex arcs, both sensory and motor pathways. These two methodologies can be promising and powerful to evaluate the functional integrity of the brainstem and cranial nerves. Keywords: Intraoperative neurophysiological monitoring (IONM); Brainstem; Corticobulbar motor evoked potential (CoMEP); Brainstem reflexes [ABSTRACT FROM AUTHOR]

Objective: To report on the value of interdigital nerve (IDN) conduction study (NCS) of the foot for the recognition of diabetic sensory polyneuropathy with normal routine NCS and the nature of electrophysiological abnormality in early diabetic sensory polyneuropathy.Methods: The sensory nerve conductions in the two digital and 4 IDNs of the foot were obtained orthodromically using the near-nerve needle and signal averaging technique.Results: In 21 patients with diabetic sensory polyneuropathy with normal routine NCS, a definite neuropathy pattern (abnormalities in more than 3 of 6 tested nerves) was observed in 12 patients (57.1%). The most common abnormalities that were found were a low amplitude in the sensory compound nerve action potential and an absent potential, indicating that early diabetic sensory polyneuropathy is due to axonal degeneration.Conclusions: Interdigital NCS of the foot using near-nerve needle technique can identify neuropathy in diabetic sensory polyneuropathy with normal routine NCS. This technique offers a useful means of detecting nerve conduction abnormalities in the early stage of diabetic polyneuropathy. [Copyright &y& Elsevier]

Introduction: This cohort study aimed to investigate the factors associated with noninvasive positive pressure ventilation adherence and assess the long-term effects of noninvasive positive pressure ventilation adherence in patients with amyotrophic lateral sclerosis (ALS). Methods: The medical records of patients with ALS admitted to a tertiary hospital for noninvasive positive pressure ventilation initiation were retrospectively reviewed. Pulmonary function parameters, variables of blood gas analysis, the site of symptom onset, the time from onset and diagnosis to noninvasive positive pressure ventilation application, ALS Functional Rating Scale-Revised, neurophysiological index, and the length of hospital stay were evaluated. The adherence to noninvasive positive pressure ventilation was defined as the use of noninvasive positive pressure ventilation for ≥ 2 h/day or ≥ 4 h/day. The correlations between noninvasive positive pressure ventilation adherence or length of hospital stay and other clinical parameters were analyzed. Results: Fifty-one patients with ALS were included in the study. The time from onset and diagnosis to NIPPV application was reduced by 16 months in the adherent group than that in the non-adherent group; however, the parameters of blood gas analysis and pulmonary function tests did not differ significantly between the groups. Furthermore, the neurophysiological index of the abductor digiti minimi muscle was higher by 4.05 in the adherent group than that in the non-adherent group. The adherence to noninvasive positive pressure ventilation prolonged tracheostomy-free survival compared to that of non-adherence. Desaturation events, lower forced vital capacity, last pCO2, bicarbonate, and base excess, and higher differences in pCO2, were associated with an increase in the length of hospital stay. Conclusions: Noninvasive positive pressure ventilation application shortly after symptom onset and ALS diagnosis in patients with CO2 retention and reduced forced vital capacity can be considered for successful adherence. Adherence to noninvasive positive pressure ventilation may result in reduced tracheostomy conversion rates and prolonged tracheostomy-free survival. [ABSTRACT FROM AUTHOR]

We performed this study to investigate the effect of intraoperative brainstem auditory evoked potential (IBAEP) changes on the development of postoperative nausea and vomiting (PONV) after microvascular decompression (MVD) for neurovascular cross compression. A total of 373 consecutive cases were treated with MVD. The use of rescue antiemetics after surgery was used as an objective indicator of PONV. IBAEP monitoring was routinely performed in all. The use of rescue antiemetics was significantly associated with female sex (OR = 3.427; 95% CI, 2.077–5.654; P < 0.001), PCA use (OR = 3.333; 95% CI, 1.861–5.104; P < 0.001), and operation time (OR = 1.017; 95% CI, 1.008–1.026; P < 0.001). A Wave V peak delay of more than 1.0 milliseconds showed a significant relation with the use of rescue antiemetics (OR = 1.787; 95% CI, 1.114–2.867; P = 0.016) and a strong significant relation with the use of rescue antiemetics more than 5 times (OR = 2.426; 95% CI, 1.372–4.290; P = 0.002). A wave V peak delay of more than 1.0 milliseconds might have value as a predictor of PONV after MVD. More detailed neurophysiological studies will identify the exact pathophysiology underlying PONV after MVD. [ABSTRACT FROM AUTHOR]

Background: Tracheostomy invasive ventilation (TIV) is applied to a subset of amyotrophic lateral sclerosis (ALS) patients; however, its frequency and impact on prognosis vary across countries. Methods: We conducted a nationwide retrospective cohort study using Korean National Health Insurance claims data. All patients diagnosed with sporadic ALS from 2012 to 2017 were included, with the observation period until 2020. The survival time between the TIV and non-TIV groups was compared using propensity score matching analysis, and prognostic factors were assessed within the TIV group. Results: This study included 3484 ALS patients (mean [standard deviation] age, 62.4 [11.9] years, 60.4% male), among whom 1230 (35.3%) underwent TIV. After 1:1 propensity score matching, the survival duration between the two groups was not significantly different (28 vs. 25 months, p = 0.057). Cox regression indicated that older age (hazard ratios [HRs] for each decade compared to <40 years: 3.89, 3.83, 5.30, 6.78, and 8.40 [ ≥ 80 years]; p < 0.005 for all) and lower income (HR, 1.28; 95% confidence interval [CI], 1.09–1.52; p = 0.003) negatively impacted survival, while gastrostomy (HR, 0.57; 95% CI, 0.50–0.66; p < 0.001) and supportive care services (HR, 0.43; 95% CI, 0.32–0.59; p < 0.001) were associated with prolonged survival. Conclusions: TIV was administered to more than one-third of Korean ALS patients without significant survival prolongation. Older age, lower income, lack of gastrostomy, and insufficient supportive care were independent poor prognostic factors for survival, underscoring the importance of comprehensive management for ALS patients. [ABSTRACT FROM AUTHOR]

Transcranial muscle motor evoked potentials (Tc-mMEPs), a key component of intraoperative neurophysiologic monitoring (IONM), effectively reflect the changes in corticospinal tract integrity and are closely related to the occurrence of the postoperative motor deficit (PMD). Most institutions have applied a specified (fixed) alarm criterion for the heterogeneous groups in terms of etiologies or lesion location. However, given the high risk of PMD in ossification of the posterior longitudinal ligament (OPLL) surgery, it is essential to determine a tailored cutoff value for IONM. We aimed to establish the intraoperative cutoff value of Tc-mMEPs reduction for predicting PMD in OPLL according to lesion levels. Retrospective analysis using a review of electrical medical records. In this study, we included 126 patients diagnosed with OPLL, who underwent surgery and IONM. The occurrence of PMD immediately and 1 year after operation, as well as the decrement of intraoperative Tc-mMEPs amplitude. We analyzed OPLL surgery outcomes using Tc-mMEPs monitoring. Limbs with acceptable baseline Tc-mMEPs in the tibialis anterior or abductor hallucis were included in the final set. PMD was defined as a ≥1 decrease in Medical Research Council score in the legs, and it was evaluated immediately and 1year after operation. The reduction ratios of Tc-mMEPs amplitude compared with baseline value were calculated at the two time points: the maximal decrement during surgery and at the end of surgery. Receiver operating characteristic curve analysis was used to determine the cutoff value of Tc-mMEPs amplitude decrement for predicting PMDs. In total, 203 limbs from 102 patients with cervical OPLL and 42 limbs from 24 patients with thoracic OPLL were included. PMD developed more frequently in thoracic lesions than in cervical lesions (immediate, 9.52% vs 2.46%; 1 year, 4.76% vs 0.99%). The Tc-mMEPs amplitude cutoff point at the end of surgery for PMD (both immediate and 1-year) was a decrease of 93% in cervical and 50% in thoracic OPLL surgeries. Similarly, the Tc-mMEPs amplitude cutoff point at the maximal decrement during surgery for PMD (both immediate and 1 year) was a reduction of 97% in cervical and 85% in thoracic OPLL surgeries. The thoracic lesion exhibited a lower cutoff value than the cervical lesion for both immediate and long-term persistent PMD in OPLL surgery (Tc-mMEPs at the end of surgery measuring 93% vs 50%; and Tc-mMEPs at the maximal decrement measuring 97% vs 85% for cervical and thoracic lesions, respectively). To enhance the reliability of monitoring, considering the application of tailored alarm criteria for Tc-mMEPs changes based on lesion location in OPLL could be beneficial. [ABSTRACT FROM AUTHOR]

A response by Sung-Min Kim and Kyung Seok Park to a letter to the editor by Chunkui Zhou and colleagues in response to their article on the concept of neuromyelitis optica spectrum disorder (NMOSD) is presented.

• Postoperative voiding dysfunction is not an uncommon neurological complication after lumbar spinal surgery. • Intraoperative bulbocavernosus reflex (BCR) loss is correlated with postoperative voiding dysfunction. • Intraoperative BCR monitoring may enhance safety during posterior lumbar fusion surgery. To assess the utility of intraoperative bulbocavernosus reflex (BCR) monitoring in posterior lumbar fusion surgery. We retrospectively evaluated 153 patients undergoing posterior lumbar fusion with intraoperative BCR monitoring. Voiding function was assessed at discharge and two follow-ups. BCR was preserved in 151 patients and completely disappeared in two patients at the end of surgery. For patients in whom BCR was preserved, voiding difficulties at discharge and 1-month and 6-month follow-ups were noted in 16 (10.6%), 9 (6.0%), and 0 (0.0%) patients, respectively. However, patients with BCR loss experienced voiding difficulties at all three time-points. Statistical analysis showed a significant difference in voiding between those with preserved and disappeared BCRs at 6 months postoperatively. BCR disappeared during surgery but recovered before the end of surgery in six patients. Among these patients, one experienced transient voiding difficulties postoperatively but with good recovery. However, the other five patients did not experience postoperative voiding difficulties. BCR had low sensitivity for voiding dysfunction at discharge, but had high accuracy at 6-month follow-up examinations. BCR loss was associated with new voiding dysfunction. Intraoperative BCR monitoring is a potentially useful tool for enhancing safety during posterior lumbar fusion by predicting postoperative voiding dysfunction. [ABSTRACT FROM AUTHOR]

Here we propose a carbon nanotube (CNT) field-effect transistor (FET) functionalized with aquaporin-4 (AQP4) extracellular loop peptides for the rapid detection of AQP4 antibody without pretreatment. Neuromyelitis optica (NMO) is a rare disease of the central nerve system that affects the optic nerves and the spinal cord. NMO-IgG, a serum antibody in patients, is highly specific for NMO and targets AQP4. We synthesized AQP4 extracellular loop peptides, known as primary autoimmune target in NMO, and immobilized them onto CNT-FET. The sensor showed p-type FET characteristics after the functionalization of peptides. The sensor was able to detect antibody with a detection limit of 1 ng l −1 . Moreover, AQP4 antibody in human serum was detected without any pretreatment. These results indicate that the biosensor can be used for rapid and simple detection of NMO antibody. [ABSTRACT FROM AUTHOR]

Introduction The aims of this study were to identify factors affecting the measurement of nerve cross-sectional area (CSA) and to establish normal reference values for nerve ultrasonography of the upper extremity. Methods Ninety-seven age-matched, healthy individuals were enrolled. Ultrasonographic tests were performed by tracing nerves from the axilla to the distal arm. CSA was measured at the following locations: median nerve (carpal tunnel inlet, forearm, antecubital fossa, midhumerus); ulnar nerve (wrist, 2 cm proximal to the wrist, forearm, cubital tunnel outlet and inlet, midhumerus); radial nerve (spiral groove, antecubital fossa); and musculocutaneous nerve (proximal humerus). Results The CSA reference values differed between the measured points along the path of each nerve. Nerve CSA correlated significantly with weight, body mass index, height, and gender; however, the CSA ratio (distal/proximal) did not correlate with demographic factors. Conclusions The normal reference values may be helpful in diagnosis of pathologies involving these nerves. Muscle Nerve 47: 864-871, 2013 [ABSTRACT FROM AUTHOR]

Introduction: The aim of this study was to determine normal reference values for cross-sectional area (CSA) and the correlation between demographic factors and CSA in the cervical roots and brachial plexus trunks using ultrasonography. Methods: Ninety-five age-matched healthy individuals were studied. Ultrasonographic tests were performed via nerve tracing from the cervical root to the brachial plexus trunk. The CSA of each nerve was measured in the C5-8 ventral roots and brachial plexus (trunk level). Results: Normal values of each cervical root were: C5, 5.66 ± 1.02 mm2; C6, 8.98 ± 1.65 mm2; C7, 10.43 ± 1.86 mm2; and C8, 10.76 ± 2.02 mm2. Values for the brachial plexus were: upper trunk, 16.70 ± 2.88 mm2; middle trunk, 14.01 ± 2.70 mm2; and lower trunk, 13.75 ± 2.57 mm2. The side-to-side discrepancy was 11.91 ± 11.11%. Body mass index (BMI) and height correlated frequently with nerve CSA. Conclusions: These reference values may be helpful in investigating pathologies involving the cervical area. Muscle Nerve 46: 711-716, 2012 [ABSTRACT FROM AUTHOR]

Abstract: Background: Glycogen synthase kinase-3β (GSK-3β) activity plays a central role in motor neuron degeneration. We hypothesized that GSK-3β inhibitor would prolong the survival of motor neuron and suppress the disease progression in amyotrophic lateral sclerosis (ALS). Methods: A total of 40 transgenic mice harboring the human G93A mutated SOD1 gene and 14 wild type mice were used following confirmation of their genotype. The 40 transgenic mice were divided into 2 groups; ALS transgenic mice_control and ALS transgenic mice_GSK-3β inhibitor treatment. The clinical status, rotarod test and survival of the transgenic ALS mice and wild-type mice were evaluated. Additionally, motor neuron counting, GSK-3β activity and extrinsic apoptotic signals in spinal cord were also investigated. Results: The treatment with GSK-3β inhibitor showed excellent motor ability and delay of the symptom onset and survival in the ALS transgenic mice. However, after clinical symptoms developed, the neuroprotective effect of GSK-3β inhibitor was not significant. And the biochemical results revealed the weakly increased extrinsic apoptotic signals in the ALS transgenic mice by GSK-3β inhibitor treatment. Conclusion: The present study suggests that GSK-3β inhibitor would be a novel promising therapeutic strategy in ALS; however neuroprotective effect of GSK-3β inhibitor may be reduced via extrinsic apoptosis or non-neuronal patho-mechanism in late-stage of disease. [Copyright &y& Elsevier]

Abstract: Objective: To address the issue as to how best to perform statistical MUNE, we applied two different approaches and compared results in healthy subjects and ALS patients. Methods: Twelve normal subjects (women 8, mean age 52years) and 11 ALS patients (women 4, mean age 54years) underwent two consecutive MUNE studies, which differed in terms of setting and modifying the recording window. These are referred to as the ‘expansion’ and ‘narrowing’ methods, respectively. Size-weighted average (Av) SMUP and MUNE values were obtained using the two methods, and compared in control and patient groups. Results: Expansion method-derived Av SMUP sizes and MUNE values differed only slightly from those obtained using the narrowing method in healthy subjects, whereas the narrowing method resulted in significantly larger Av SMUP sizes and smaller MUNE values than the expansion method in ALS patients (Wilcoxon signed ranks test, p =0.003). The sizes of tested areas (mean±SD) were significantly larger for the narrowing method than the expansion method in both subject groups with much greater difference in ALS patients; 9.6±3.1% vs. 7.9±1.7% in healthy subjects and 16.1±5.1% vs. 11.2±3.0% in ALS patients (Student t-test, p <0.01). Conclusions: The present study shows, unlike that found in normal subjects, that the results of statistical MUNE in ALS patients are heavily dependent on the approach used to set and modify recording windows. Significance: The expansion method using a 10%-sized window is likely to suffer from systemic errors due to the ceiling effect and the sampling of artifactually small motor units in ALS patients. The authors recommend that the narrowing method be considered as an alternative that avoids these problems. [Copyright &y& Elsevier]

• Intraoperative blink reflex (BR) monitoring helps optimize the effectiveness of microvascular decompression for hemifacial spasm. • Compared with lateral spread response, intraoperative BR monitoring shows better predictive value. • Intraoperative BR monitoring might be a useful and reliable prognostic predictor of surgical outcome. To investigate the prognostic and predictive value of intraoperative blink reflex (BR) monitoring during microvascular decompression (MVD) for hemifacial spasm (HFS). We retrospectively reviewed 41 patients with HFS undergoing MVD with intraoperative BR and lateral spread response (LSR) monitoring. Facial spasm was evaluated for six months postoperatively. The BR resolved in 38 patients and persisted in three after MVD. For patients who exhibited BR resolution, 1-day, 1-month, and 6-month follow-ups revealed that 35 (92.1%), 35 (92.1%), and 38 (100%) patients had spasm resolution, respectively. However, of the three patients with persistent BR, one (33.3%), one (33.3%), and zero (0%) patients exhibited spasm resolution at the three corresponding follow-ups. We found a statistically significant difference in spasm resolution between the persistent and resolved BR groups at six months postoperatively. A comparison between intraoperative BR and LSR monitoring revealed that BR was a better predictor of clinical outcomes. Intraoperative BR monitoring is a potentially useful tool to help facilitate an adequate decompression and is a reliable prognostic predictor of surgical outcome. This study is the first to document the relationship between intraoperative BR monitoring and surgical outcome in patients with HFS. [ABSTRACT FROM AUTHOR]

• Eyelid drooping of 1.5 mm or more after sustained upgaze is specific for ocular myasthenia gravis. • Sustained upgaze before performing the ice-pack test increased the sensitivity for diagnosing ocular myasthenia. • Sustained upgaze is particularly useful for diagnosing ocular myasthenia in Asians who have absent or low eyelid crease. The accuracy of the ice-pack test for diagnosing myasthenia gravis (MG) has been reported to be excellent, however, the sensitivity is low in patients with mild ptosis which is common in Asians who have absent or low double eyelid folds. Herein, we performed the ice-pack test after sustained upgaze and tested its validity for diagnosing MG. The study included 30 newly diagnosed MG patients with ptosis (median age 47 years, range 2–87 years) and 30 controls with ptosis other than MG (median age 58 years, range 5–83 years). All MG patients initially presented with ptosis and/or diplopia; 26 patients had purely ocular MG while 4 patients progressed to generalized MG. All patients performed the new ice-pack test after sustained upgaze for 2 min. The ice-pack test was judged positive if there was an improvement of at least 2 mm of margin reflex distance compared to the level of ptosis before (conventional ice-pack test) or after (new ice-pack test) sustained upgaze. Subgroup analysis was performed according to the level of ptosis. The conventional test showed 43.3% sensitivity and 100% specificity for diagnosing MG, while the new ice-pack test achieved 73.3% sensitivity and 96.7% specificity, respectively. In patients with mild ptosis, the sensitivity and specificity for diagnosing MG were 27.8% and 100% by the conventional test, and 72.2% and 96.7% by the new ice-pack test, respectively. The new ice-pack test combined with sustained upgaze was more sensitive for diagnosing MG, particularly in patients with mild ptosis which is common in Asians. [ABSTRACT FROM AUTHOR]

Highlights • The associated factors for baseline mMEP recording failure were different based on lesion locations. • Preoperative motor power showed a close correlation with the failure rate of baseline mMEP generation. • Baseline mMEP generation failure in thoracic lesion could indicate risk for postoperative deficits. Abstract Objective To identify factors associated with the failure to generate baseline muscle motor evoked potentials (mMEPs) during spinal surgery, and to determine the association between baseline mMEP generation and postoperative outcomes. Methods A total of 345 patients who underwent spine surgery with intraoperative mMEP monitoring were included, and we retrospectively reviewed their demographic/clinical parameters, and mMEP recording results according to lesion locations. Results Multivariable logistic regression analysis revealed that preoperative Medical Research Council grade of the weakest muscle <3 was significantly associated with failure of baseline mMEP generation in both cervical and thoracic lesions. In addition, high intramedullary T2 signal intensity on spine MRI for cervical lesions and male sex for thoracic lesions were also significantly associated with baseline mMEP generation failure. Moreover, the failure of baseline mMEP generation was a significantly associated factor for poor functional outcome in patients with thoracic lesions. Conclusion Sex, radiological abnormality, and preoperative functional status were associated with baseline mMEP generation failure during spine surgery with different patterns according to lesion location. Moreover, baseline mMEP generation failure in thoracic lesion could be associated with risk of postoperative deficits. Significance The risk of baseline mMEP recording failure could be evaluated based on preoperative clinical parameters. [ABSTRACT FROM AUTHOR]

Introduction: Thyrotoxic periodic paralysis (TPP) is characterized by recurrent episodes of reversible paralysis with hyperthyroidism. It is clinically similar to hypokalemic periodic paralysis (HOPP), which features significant ion-channel dysfunction and reduced muscle fiber conduction velocity (MFCV). However, the muscle membrane function in TPP is not known.Methods: For 13 patients with TPP and 15 age-matched controls, clinical assessment and serial neurophysiological testing, including nerve conduction, prolonged exercise (PE) testing, and MFCV. were performed.Results: MFCV values were elevated up to 1 year from the paralytic attack in TPP patients. In the group with a positive PE test, MFCV values were higher. There was no significant relationship between MFCV values and either hypokalemia or hyperthyroidism.Conclusions: Although clinical manifestations in TPP are similar to those observed in HOPP, TPP appears to feature an alternate pathogenic mechanism. Specifically, MFCV values increased rather than decreased. Further studies are needed to support these findings. Muscle Nerve, 2016 Muscle Nerve 56: 780-786, 2017. [ABSTRACT FROM AUTHOR]

Background: Neuromyelitis optica spectrum disorder with aquaporin4-immunoglobulin G (NMOSD-AQP4) is an inflammatory disease characterised by a high female predominance. However, the effect of gender in patients with NMOSD-AQP4 has not been fully evaluated. Objective: The aim of this study was to determine the effect of gender in clinical manifestations and prognosis of patients with NMOSD-AQP4. Methods: The demographics, clinical and radiological characteristics, pattern reversal visual evoked potential (VEP) test results, and prognosis of 102 patients (18 males) with NMOSD-AQP4 were assessed. Results: Male patients had a higher age at onset (48.7 vs 41 years, p = 0.037) and less optic neuritis as the onset attack (17% vs 44%, p = 0.026), higher tendency to manifest as isolated myelitis over the follow-up period (67% vs 28%, p = 0.005), fewer optic neuritis attacks per year (0.08 vs 0.27, p < 0.001), and shorter relative P100 latency on VEP testing (97.1% vs 108.3%, p = 0.001). Moreover, male gender was significantly associated with the absence of optic neuritis attacks over the follow-up period independent of their age of onset. Conclusion: In NMOSD-AQP4 patients, gender impacts on disease onset age and site of attack. This may be an important clue in identifying NMOSD-AQP4 patients with limited manifestations as well as in predicting their clinical courses. [ABSTRACT FROM AUTHOR]

Neuromyelitis optica (NMO) is an inflammatory demyelinating disease of the central nervous system (CNS). Hydroxycholesterols (OHCs), metabolites of CNS cholesterol, are involved in diverse cellular responses to inflammation and demyelination, and may also be involved in the pathogenesis of NMO. We aimed to develop a sensitive and reliable method for the quantitative analysis of three major OHCs (24S-, 25-, and 27-OHCs), and to evaluate their concentration in the cerebrospinal fluid (CSF) and serum of patients with NMO. The levels of the three OHCs in the serum and CSF were measured using liquid chromatography-silver ion coordination ionspray tandem mass spectrometry and liquid chromatography-electrospray ionization tandem mass spectrometry with picolinyl ester derivatization, respectively. The linear range was 5–250 ng/mL for 24S- and 27-OHC, and 0.5–25 ng/mL for 25-OHC in serum, and was 0.1–5 ng/mL for 24S- and 27-OHC, and 0.03–1 ng/mL for 25-OHC in CSF. Precision and accuracy were 0.5%–14.7% and 92.5%–109.7%, respectively, in serum, and were 0.8%–7.7% and 94.5%–119.2%, respectively, in CSF. Extraction recovery was 82.7%–90.7% in serum and 68.4%–105.0% in CSF. When analyzed in 26 NMO patients and 23 control patients, the 25-OHC (0.54 ± 0.96 ng/mL vs. 0.09 ± 0.04 ng/mL, p = 0.032) and 27-OHC (2.68 ± 3.18 ng/mL vs. 0.68 ± 0.25 ng/mL, p = 0.005) were increased in the CSF from NMO patients. When we measured the OHCCSF index that controls the effects of blood–brain barrier disruption on the level of OHC in the CSF, the 27-OHCCSF index was associated with disability (0.723; 95% confidence interval (CI)– 0.181, 0.620; p = 0.002), while the 24-OHCCSF index (0.518; 95% CI– 1.070, 38.121; p = 0.040) and 25-OHCCSF index (0.677; 95% CI– 4.313, 18.532; p = 0.004) were associated with the number of white blood cells in the CSF of NMO patients. Our results imply that OHCs in the CNS could play a role in the pathogenesis of NMO. [ABSTRACT FROM AUTHOR]

Background: The aquaporin-4 antibody (AQP4-Ab) is a disease-specific autoantibody to neuromyelitis optica (NMO). We aimed to evaluate the accuracy of the FACS assay in detecting the AQP4-Ab compared with the commercial cell-based assay (C-CBA) kit. Methods: Human embryonic kidney-293 cells were transfected with human aquaporin-4 (M23) cDNA. The optimal cut off values of FACS assay was tested using 1123 serum samples from patients with clinically definite NMO, those at high risk for NMO, patients with multiple sclerosis, patients with other idiopathic inflammatory demyelinating diseases, and negative controls. The accuracy of FACS assay and C-CBA were compared in consecutive 225 samples that were collected between January 2014 and June 2014. Results: With a cut-off value of MFIi of 3.5 and MFIr of 2.0, the receiver operating characteristic curve for the FACS assay showed an area under the curve of 0.876. Among 225 consecutive sera, the FACS assay and C-CBA had a sensitivity of 77.3% and 69.7%, respectively, in differentiating the sera of definite NMO patients from sera of controls without IDD or of MS. Both assay had a good specificity of 100% in it. The overall positivity of the C-CBA among FACS-positive sera was 81.5%; moreover, its positivity was low as 50% among FACS-positive sera with relatively low MFIis. Conclusions: Both the FACS assay and C-CBA are sensitive and highly specific assays in detecting AQP4-Ab. However, in some sera with relatively low antibody titer, FACS-assay can be a more sensitive assay option. In real practice, complementary use of FACS assay and C-CBA will benefit the diagnosis of NMO patients, because the former can be more sensitive among low titer sera and the latter are easier to use therefore can be widely used. [ABSTRACT FROM AUTHOR]

Introduction: The split-hand phenomenon refers to preferential wasting of the thenar muscles with relative sparing of the hypothenar muscles in amyotrophic lateral sclerosis (ALS).Methods: We compared the split-hand index (SI) calculated from the compound muscle action potential (CMAP; SICMAP ) with that calculated from the motor unit number index (MUNIX; SIMUNIX ). We performed MUNIX on the abductor policis brevis (APB), first dorsal interosseous (FDI), and abductor digiti minimi (ADM) muscles of 39 ALS patients and 40 age-matched, healthy controls. SI is derived by multiplying the CMAP (or MUNIX) recorded over the APB and FDI and dividing by the CMAP (or MUNIX) recorded over the ADM.Results: Receiver-operating characteristic curve analysis revealed good diagnostic accuracy for both indices, but better performance of SIMUNIX than SICMAP .Conclusion: SIMUNIX and SICMAP were useful in differentiating ALS patients from healthy controls. SIMUNIX appears to be a better electrophysiological marker than SICMAP for the split-hand sign of ALS. Muscle Nerve 53: 885-888, 2016. [ABSTRACT FROM AUTHOR]

ABSTRACT Introduction: Split hand is considered to be a specific feature of amyotrophic lateral sclerosis (ALS). Methods: We evaluated the pattern difference of intrinsic hand muscles of upper limb-onset ALS (UL-ALS), upper limb-onset progressive muscular atrophy (UL-PMA), brachial amyotrophic diplegia (BAD), and Hirayama disease (HD) by measuring objective electrophysiological markers. Results: The abductor digiti minimi (ADM)/abductor pollicis brevis (APB) compound muscle action potential (CMAP) amplitude ratio was significantly higher in UL-ALS than other variants, but a considerable proportion of UL-ALS cases had an amplitude ratio in the range of other variants. Absent APB CMAP and abnormally high ADM/APB CMAP amplitude ratio (≥4) occurred only with UL-ALS. Conversely, an absent ADM CMAP was identified only in UL-PMA and BAD. Conclusions: The absolute ADM/APB CMAP amplitude ratio was not specific for ALS; however, several findings from simple electrophysiological measurements may help predict prognosis in patients with motor neuron diseases and may be early diagnostic markers for ALS. Muscle Nerve 51: 333-337, 2015 [ABSTRACT FROM AUTHOR]

ABSTRACT Introduction: Cross-sectional area (CSA) reference values of lower extremity nerves using ultrasonography have only been reported in a few studies and have been limited to white populations. Methods: For this study, 94 healthy Korean volunteers were recruited for measurement of the CSA at 7 sites of lower extremity nerves. The side-to-side difference in CSA was calculated for each nerve, and reference ranges were derived. External validity evaluation for the reference values was performed with 10 newly recruited volunteers at a different institution. Results: Nerve CSA was correlated significantly with body mass index, weight, and height; however, the absolute value of the side-to-side difference had no significant correlation with demographic factors. The external validity was adequate for all sites, ranging from 80% to 100%. Conclusions: The lower extremity nerve CSA values obtained in this study may provide normal reference values for the Asian population. Muscle Nerve 50: 564-570, 2014 [ABSTRACT FROM AUTHOR]

Highlights: [•] JGK-263 can reduce apoptosis by inactivating the intrinsic apoptosis pathway. [•] JGK-263 can reduce apoptosis by inactivating the extrinsic apoptosis pathway. [•] JGK-263 may be effective in preventing motor neuron cell death. [•] JGK-263 has a neuroprotective effect in motor neuron cells. [ABSTRACT FROM AUTHOR]

Background: Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that leads to progressive weakness of the respiratory and limb muscles. Consequently, most patients with ALS exhibit progressive hypoventilation, which worsens during sleep. The aim of this study was to evaluate the relationship between nocturnal hypoxia and cognitive dysfunction and to assess the pattern of nocturnal hypoxia in patients with ALS. Method: Twenty-five patients with definite or probable ALS underwent neuropsychologic testing, nocturnal pulse oximetry, and capnography. Patients were grouped according to the presence of nocturnal hypoxia (SpO2<95% for ≥10% of the night) and their clinical characteristics and cognitive function were compared. Results: Compared to patients without nocturnal hypoxia, those with nocturnal hypoxia (n = 10, 40%) had poor memory retention (p = 0.039) and retrieval efficiency (p = 0.045). A cluster-of-desaturation pattern was identified in 7 patients (70%) in the Hypoxia Group. Conclusions: These results suggest that nocturnal hypoxia can be related to cognitive dysfunction in ALS. In addition, a considerable number of patients with ALS may be exposed to repeated episodes of deoxygenation–reoxygenation (a cluster-of-desaturation pattern) during sleep, which could be associated with the generation of reactive oxygen species. Further studies are required to define the exact causal relationships between these phenomena, the exact manifestations of nocturnal cluster-of-desaturation patterns, and the effect of clusters of desaturation on ALS progression. [ABSTRACT FROM AUTHOR]

The article presents a study which evaluates the utility of aquaporin-4 antibodies (AQP4-Ab) in patients with neuromyelitis optica spectrum disorders (NMOSD). It notes that the radiological and clinical features of 78 patients with NMOSD and 22 with multiple sclerosis (MS) who were examined with AQP4-Ab by a cell-based assay were assessed. Results show that the mean time interval between symptom onset and development of optic neuritis and myelitis was 39.9 months in neuromyelitis optica (NMO).

Abstract: Objective: The aim of the study is to evaluate the efficacy of muscle motor evoked potentials (mMEPs) in individual leg muscles for spinal surgery monitoring. Methods: Data were obtained from 209 patients who underwent spine surgery with intra-operative mMEP monitoring in the tibialis anterior (TA) and abductor hallucis (AH) muscles. The mMEP generation, pattern-specific mMEP loss and recovery, and the accuracy of individual mMEP changes in predicting postoperative motor deficit were assessed. Results: Generation rate of mMEPs was higher in the AH than in the TA (p <0.001). The mMEP in the TA was more sensitive in detecting mMEP loss than in the AH (p <0.001); however, mMEP in the AH was more sensitive in detecting mMEP recovery (p <0.001). The mMEPs in the TA had high sensitivity in predicting sustained postoperative motor deficits. By contrast, mMEPs in the AH showed a high positive predictive value. Conclusions: Although mMEPs were generated at a high rate in the AH, mMEP in the TA can play an important complementary role in intra-operative mMEP monitoring, because mMEP in the TA can be more sensitive to potential neural damage. Significance: Using a combination of muscles with individual sensitivities and clinical significances will improve intra-operative mMEP monitoring strategies. [Copyright &y& Elsevier]

Neuromyelitis optica (NMO), mainly affecting optic nerve and spinal cord, can also manifest diverse ocular symptoms due to brain abnormalities. We present a cortical oscillopsia without nystagmus or head tremor in a patient with neuromyelitis optica spectrum disorder (NMOSD) with anti-aquaporin 4 antibody. This rare ocular manifestation, which is easily underestimated owing to absence of the typical nystagmus, can be an initial manifestation of NMOSD. [ABSTRACT FROM AUTHOR]

Abstract: Background: Differentiating neuromyelitis optica (NMO) from multiple sclerosis (MS) is a real challenge in the clinical field. In the past, NMO (not MS), was inferred when abnormality was not detected in the brain magnetic resonance imaging (MRI). Recently, some studies have reported abnormalities in the brain MRIs of NMO, but only few among the Asian population. The aim of this study was to evaluate the frequency of brain MRI among Korean NMO patients and characterize findings that might be helpful to distinguish NMO from MS. Methods: Medical records, NMO-IgG, and brain MRI of 17 patients diagnosed with NMO by the revised diagnostic criteria of Wingerchuk et al. (2006) from 2008 to 2010, were reviewed. Results: 11 out of 17 patients (64.7%) had abnormal MRI findings. More than two lesions were detected in most patients. The majority of patients with brain MRI abnormality showed nonspecific (5 patients) or atypical (6 patients) findings. Cerebral white matter was most frequently involved (58.8%). 3 patients (17.6%) involved corpus callosum, 4 (23.5%) with internal capsule, 2 (11.8%) with cerebellum, and 3 (17.6%) with brainstem. There were 5 (29.4%) patients who met the Paty et al. criteria (1988) and 3 patients (35.3%) who met the multiple sclerosis (MS) spatial distribution diagnostic criteria of Barkhof et al. (1997) in their brain MRI. Conclusions: Brain abnormalities have been frequently found among Korean NMO patients and the frequencies have been reported to be higher than that of Caucasians. Current MS spatial distribution criteria, such as Paty et al. (1988) or Barkhof et al. (1997) , are not sufficient to discriminate NMO from MS in brain MRI findings. Our results will provide valuable information that would be useful in establishing future revising criteria for NMO. [Copyright &y& Elsevier]

The pathophysiology of axonal Guillain-Barré syndrome (GBS) is not simple axonal degeneration, but includes reversible conduction failure. Acute motor axonal neuropathy (AMAN) and acute motor conduction block (CB) neuropathy are the two subtypes of pure motor axonal GBS, but their nosologic boundary is still in debate. We investigated clinical and electrophysiological features of 21 consecutive patients with GBS in Korea. Analysis was focused on the presence of CB at intermediate nerve segments (iCB) in pure motor GBS, and its serial changes during the acute phase of disease. Pure motor GBS was common (81%), and iCB was observed in 12 patients with pure motor GBS. Clinical features of pure motor GBS with iCB were distinct from sensorimotor GBS, but similar to pure motor GBS without iCB, characterized by frequent preceding diarrhea, uncommon cranial nerve palsy, and fast recovery. The iCB was not restricted to common entrapment sites, and the distal segments were also commonly involved in the nerves with iCB. The temporal course of iCB was marked by a rapid and often disproportionate increase of proximal and distal amplitudes without remyelinating slow components. Clinical and electrophysiological features of pure motor GBS in patients with iCB suggest that acute motor CB neuropathy may constitute a spectrum of axonal GBS, sharing a common pathomechanism with AMAN. [ABSTRACT FROM AUTHOR]

The motor unit number index (MUNIX) refers to an electrophysiologic technique that measures the approximate number of motor units using the surface electromyographic interference pattern (SIP) recorded during voluntary contraction. This study was done to assess the reproducibility of MUNIX performed on hypothenar muscles in 62 normal controls and 22 amyotrophic lateral sclerosis (ALS) patients. Inter- and intraoperator correlation coefficients for MUNIX were 0.74 and 0.86, respectively, in normal controls, and 0.95 and 0.93, respectively, in ALS patients ( P < 0.01 in all). Inter- and intraoperator coefficients of variation for MUNIX measurements were 17.5% and 15.3%, respectively, in normal controls, and 23.7% and 24.0%, respectively, in ALS patients. This study shows a good correlation for MUNIX between intra- and interoperator results in both normal controls and ALS patients. The test-retest variability seems to be greater in ALS patients compared with normal controls, but this will need to be confirmed in future studies. Sources of variability should be identified and corrected for clinical use. Muscle Nerve 42: 808-813, 2010 [ABSTRACT FROM AUTHOR]

Abstract: Hereditary spastic paraplegia (HSP) is a group of genetically heterogenous neurodegenerative disorders characterized by progressive spasticity and weakness of both lower extremities. Herein, we report a novel splicing mutation (c.870+3A>G) in SPG4 in a Koran family with an autosomal dominant-inherited pure HSP. The mutation is located in intron 5, and results in a deletion of the 188bp-sized exon 5. It is likely that the exon 5 deletion leads to spastin dysfunction and cause the typical symptoms and signs of patients. [Copyright &y& Elsevier]

Abstract: Objectives: The aims of this study were to obtain data on the frequency with which Korean patients with autoimmune myasthenia gravis (MG) present solely with ocular disturbances and progress to develop generalized disease and to identify the prognostic factors associated with secondary generalization. Methods: We conducted a retrospective multicenter survey in which a total of 376 adult patients who were newly diagnosed with MG from 2000 through 2005 were reviewed for analysis. Patients with ocular MG at the time of symptom presentation (n =202, 53.7%) were divided into two subgroups according to their prognosis: the patients whose disease remained ocular throughout the follow-ups were placed in the OMG-R group, and the patients who progressed to develop generalized disease were placed in the OMG-G group. Clinical characteristics and laboratory findings were compared between the two subgroups. Results: Secondary generalization developed in 47 (23.3%) of the 202 study subjects, mostly within the first 6 months after symptom presentation, while the disease remained ocular throughout the follow-up duration (median 11.8 months) in the remaining 155 patients (76.7%). AChR antibody, abnormal repetitive nerve stimulation tests (RNST) and thymoma were more frequently observed in the patients in the OMG-G group than in those in the OMG-R group (p <0.01 in all). In seropositive cases, the titers of AChR antibody were also significantly higher in the OMG-G group than in the OMG-R group (median, 3.8 nM vs. 6.4 nM; p <0.05). Cox proportional hazards regression analyses showed that early oral prednisolone treatment significantly reduced the risk of secondary generalization (HR, 0.24; 95% CI, 0.11–0.56), whereas abnormal AChR antibody (HR, 5.34; 95% CI, 1.60–17.8) and thymoma (HR, 2.32; 95% CI, 1.21–4.45) were predictive of the development of secondary generalization. Conclusions: Our findings suggest that several factors, including the AChR antibody, thymoma, early corticosteroid treatment, and possibly latent neuromuscular abnormality revealed by RNST, may have an impact on the risk of developing generalized disease in Korean patients presenting with ocular myasthenia. [Copyright &y& Elsevier]

BACKGROUND AND PURPOSE We attempted to measure DTI parameters of the brainstem pyramidal tract using two approaches, ie, simple ROI and tract-specific analyses. Results obtained for healthy subjects and ALS patients were compared. METHODS DTI was performed using a single shot SE-EPI with 25 noncollinear diffusion gradient directions ( b= 1000 second/mm2) and with no diffusion gradient on a 3.0-T MR system in 10 ALS patients and in 8 age- and sex-matched normal controls. To delineate the brainstem pyramidal tract, tractography was performed using two ROIs, ie, a seed ROI at the cerebral peduncle (ROI-1) and a target ROI at the lower pons (ROI-2). ROI-1 was subsequently restricted to voxels that contained streamlines in the tract reconstruction, thus creating a sub-ROI. RESULTS Mean fractional anisotropy (FA) and mean diffusivity values were highly reproducible by tract specific analysis, whereas simple ROI analysis yielded larger variabilities between operators. FA values were significantly lower in ALS patients than in normal controls in the tractography-derived sub-ROI ( P= .01), but not in the seed or target ROIs. CONCLUSIONS These results suggest, compared with simple ROI analysis, that tract-specific analysis using DTI fiber-tracking is more reliable and sensitive for detecting upper motor neuron pathology in ALS. [ABSTRACT FROM AUTHOR]

Abstract: Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease caused by selective motor neuron death, and currently no effective treatment is available for ALS. In this study, we investigated the neuroprotective effects of pyruvate, which acts as an anti-oxidant and as an energy source. We treated G93A SOD1 transgenic mice with pyruvate (from 70 days of age, i.p., at 1000mg/kg/week), and found that it prolonged average lifespan by 12.3 days (10.5%), slowed disease progression, and improved motor performance, but did not delay disease onset. Pyruvate treatment was also associated with reduced nitrotyrosine immunoreactivity, gliosis, and increased Bcl-2 expression in the spinal cords of G93A SOD1 transgenic mice. These results suggest that pyruvate treatment may be a potential therapeutic strategy in ALS. [Copyright &y& Elsevier]

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder characterized by motor neuron involvement. Mutations in the human Cu/Zn superoxide dismutase (SOD1) gene are found in some cases of familial ALS. Many studies have reported SOD1 mutation-related neurodegeneration. However, whether or not a mutant SOD1 affects neural development has not been demonstrated. We developed motor neuron-neuroblastoma hybrid cells that expressed a mutant (G93A) or the wild type (WT) SOD1. Cells were differentiated by dibutyryl cAMP and aphidicolin. The mutant showed a defect in neurite outgrowth and had decreased viability. Cytochrome c released and nuclear fragmentation were observed. Western blot analysis showed that the amount of neurofilament and microtubule associated proteins-2 (MAP-2) decreased during differentiation. These results suggest that the defect in neurite outgrowth of mutant SOD1 cells is a cytoskeletal defect and is associated with neuronal death. [Copyright &y& Elsevier]