Sural Nerve Conduction Velocity Research Articles

Glycemic variability is associated with sural nerve conduction velocity in outpatients with type2diabetes: Usefulness of a new point-of-care device for nerve conduction studies.

Although several studies have shown the association between continuous glucose monitoring (CGM)-derived glycemic variability (GV) and diabetic peripheral neuropathy, no studies have focused on outpatients or used NC-stat®/DPNCheck™, a new point-of-care device for nerve conduction study (NCS). We investigated the association between CGM-derived GV and NCS using DPNCheck™ in outpatients with type 2 diabetes, and further analyzed the difference in results between patients with and without well-controlled HbA1c levels. All outpatients with type 2 diabetes using the CGM device (FreeStyle Libre Pro®) between 2017 and 2022 were investigated. Sural nerve conduction was evaluated by sensory nerve action potential (SNAP) amplitude and sensory conduction velocity (SCV) using DPNCheck™. Associations of CGM-derived GV metrics with SNAP amplitude and SCV were investigated. In total, 304 outpatients with type 2 diabetes were included. In a linear regression model, most CGM-derived GV metrics except for the mean amplitude of glucose excursion and low blood glucose index were significantly associated with SCV, but not with SNAP amplitude. The significant associations of most CGM-derived GV metrics with SCV remained after adjustment for possible confounding factors, but not after adjustment for glycated hemoglobin (HbA1c). Most CGM-derived GV metrics were significantly associated with SCV after adjustment for HbA1c in patients with a HbA1c ≤ 6.9%, but not in those with a HbA1c ≥ 7.0%. In outpatients with type 2 diabetes, multiple CGM-derived GV metrics were significantly associated with SCV obtained by DPNCheck™. GVmay have independent impacts on peripheral nerve function, particularly in patients with well-controlled HbA1c levels.

High serum levels of CCL11/Eotaxin-1 are associated with diabetic sensorimotor polyneuropathy and peripheral nerve function but not with cardiac autonomic neuropathy in people with type 2 diabetes

ABSTRACT Aims To investigate whether higher serum CCL11/Eotaxin-1, a biomarker for aging and neurodegenerative and neuroinflammatory disorders, is associated with diabetic sensorimotor polyneuropathy (DSPN), peripheral nerve dysfunction, and cardiac autonomic neuropathy in people with type 2 diabetes. Methods This cross-sectional study included 106 patients with type 2 diabetes and 40 healthy controls, matched for the age and sex distribution of the diabetes group as a whole. The CC chemokines CCL11/Eotaxin-1 and CCL22/MDC were measured in fasting serum samples. DSPN and peripheral nerve function were assessed by neurological examination and nerve conduction studies, and cardiac autonomic function, by heart rate variability (HRV) and corrected QT (QTc) time. The cardio-ankle vascular index (CAVI) was measured as a marker for arterial stiffness. Results Serum CCL11/Eotaxin-1 levels were significantly higher in diabetic patients than in healthy controls (183 ± 63.5 vs. 113.1 ± 38.5 pg/ml, p < 0.001), but serum CCL22/MDC levels were not significantly different between the two groups. In the diabetes group, the serum CCL11/Eotaxin-1 level was positively correlated with ulnar and sural nerve conduction velocities (p = 0.0009, p = 0.0208, respectively) and sensory nerve action potential (p = 0.0083), and CAVI (p = 0.0005), but not with HRV indices or QTc time, and serum CCL22/MDC was not significantly correlated with any indices of nerve conduction. In a model adjusted for age and duration of diabetes, serum CCL11/Eotaxin-1 was still associated with ulnar nerve conduction velocity (p = 0.02124). Serum CCL11/Eotaxin-1, but not CCL22/MDC, was significantly higher in patients with than in those without DSPN (208.2 ± 71.6 vs. 159.1 ± 45.1 pg/ml, respectively; p < 0.0001). Conclusions Serum CCL11/Eotaxin-1 is elevated in patients with DSPN and is associated with peripheral nerve dysfunction, in particular sensory nerve conduction velocity, suggesting that serum CCL11/Eotaxin-1 may be a potential biomarker for DSPN. Clinical Trial Registration University Hospital Medical Information Network (UMIN) Clinical Trials Registry (UMIN000040631).

Sural nerve involvement in patients with acute inflammatory demyelinating polyneuropathy variant of Guillain-Barre syndrome with sural sparing at initial presentation

Introduction: Neurophysiological testing is a valuable tool in the diagnosis of Guillain-Barre syndrome (GBS). Sural sparing is a usual feature of acute inflammatory demyelinating polyneuropathy (AIDP) type GBS. However, sural involvement has been reported in later stages of GBS. It is important to identify patterns of sural nerve involvement to differentiate GBS from its mimickers and to stage the disease. This research aimed to detect the pattern of sural nerve involvement in AIDP-GBS cases with normal electrophysiological responses in the sural nerve at the beginning.Objectives: To determine the location and timing of sural nerve involvement in AIDP-GBS.Methods: This prospective follow up study included diagnosed cases of AIDP-GBS with preserved bilateral sural responses. Nerve conduction and somatosensory evoked potentials (SSEP) were done on admission and weekly thereafter for four consecutive weeks. The last evaluation was done four weeks after the fourth study.Results: All patients (100%) showed normal distal sural responses over the initial four weeks of follow up. They continued to remain normal up to eight weeks in eight patients (53.3%). Two patients had gradual prolongation of their sural SSEP on consecutive studies. One of them had gradual reduction of sural sensory nerve action potential and nerve conduction velocity along with the prolongation of sural SSEP latencies. The difference of SSEP latency increments in the left sural nerve of these two patients was statistically significant (p&lt;0.05). The right sural SSEP latency difference was not significant.Conclusion: Sparing of the distal sural sensory response was demonstrated in 100% of AIDP-GBS cases during the first four weeks of follow up. More than 50% of the cohort demonstrated preserved sural sensory responses for eight weeks from the initial presentation. Two out of fifteen patients showed statistically significant proximal sural sensory pathway involvement with increasing SSEP latencies. This finding suggests that in some patients, the sural sensory pathway may get affected at its proximal segments or at the central nervous system before the distal nerve is affected.

Excitability of somatosensory cortex is increased in ALS: A SEP recovery function study

ObjectiveNeuronal loss in the somatosensory, as well as the motor cortex in amyotrophic lateral sclerosis (ALS), indicative of a structural abnormality has been reported. Previously we have shown that afferent inhibition was impaired in ALS, suggestive of sensory involvement. In this study, we aimed to evaluate excitability changes in the somatosensory cortex of ALS patients. MethodsALS patients underwent a paired pulse somatosensory evoked potential (SEP) paradigm at various interstimulus intervals (ISI). The amplitude ratio obtained by dividing the amplitude of paired pulse SEP stimulation S2 (paired pulse stimulation) to S1 (the single pulse stimulation) was considered the somatosensory cortex excitability parameter. Findings were compared to the results obtained from healthy controls. Resting motor threshold (RMT) was also assessed in the ALS group. ResultsAn increased S2/S1 ratio was found in the ALS group in every ISI examined. Additionally, the reduced inhibition correlated negatively with forced vital capacity, Medical Research Council sum score, median nerve compound muscle action potential amplitude, while there was a positive association with Penn upper motor neuron score and sural nerve conduction velocity. No correlation existed with RMT. ConclusionsOur findings demonstrated increased somatosensory cortical excitability in ALS, which was associated with clinical parameters such as reduced pulmonary function and motor strength. SignificanceSomatosensory cortical excitability is impaired in ALS. Whether this is associated with increased motor cortical excitability requires further studies.

Comparison of nerve conduction velocities of lower extremities between football players and controls

This study aimed to compare neuronal function in the lower limbs of elite footballers and an age-matched control group. Conduction velocity, response latency and amplitude following electrical stimulation were investigated. Thirty male football players and 30 untrained males comprised the subject and control groups, respectively. We showed that professional football players have significantly slower sural nerve conduction velocity than untrained controls (p&lt;0.05). Although we found no signs of neuropathy, mild changes in nerve conduction velocity were evident in the sural nerve of the players. Motor conduction velocity of tibial nerve was also significantly prolonged in this group when comparing dominant and non-dominant extremities (p&lt;0.05). The tibial nerve muscle action potential amplitude was lower in the players’ dominant limbs compared with the controls (p&lt;0.05). We found no statistical difference in motor conduction velocities, distal latencies and amplitudes of the common peroneal nerve when comparing players and controls in both dominant and non-dominant limbs (p&gt;0.05). Our results showed abnormalities of function in the sural and tibial nerves in football players compared with untrained controls, which may indicate early signs of neuropathy.

Specific exercise is medicine – Preventing and treating a peripheral neuropathy

Introduction&#x0D; Neuropathies are a prevalent, heterogeneous group of diseases of the peripheral nervous system. Symptoms are often debilitating, difficult to treat, and usually become chronic. Not only do they diminish patients’ quality of life, but they can also affect medical therapy and lead to complications. To date, for most conditions there are no evidence-based causal treatment options available. Specific exercise interventions have proven beneficial to reduce and even prevent a neuropathy.&#x0D; Objective&#x0D; Our objective in a systematic review with meta-analysis was to analyze exercise interventions for neuropathic patients in order to evaluate the potential benefits of exercise on neuropathies of different origin that can then be translated into practice.&#x0D; Methods&#x0D; Two independent reviewers performed a systematic review with meta-analysis according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Inclusion criteria according to the PICOS approach were: neuropathic patients, exercise interventions only, an inactive or non-exercising control group, and solely randomized controlled trials with the following outcome parameters: neuropathic symptoms, balance parameters, functional mobility, gait, health-related quality of life, and HbA1c (glycated hemoglobin).&#x0D; Results&#x0D; A total of 41 randomized, controlled trials met all inclusion criteria, 20 could be included in the quantitative analysis. Study quality varied from moderate to high. Current data further support the hypothesis that exercise is beneficial for neuropathic patients. This is best documented for patients with diabetic peripheral neuropathy (DPN; 27 studies) as well as for chemotherapy-induced peripheral neuropathy (CIPN; nine studies), while there are only few studies (five) on all other causes of neuropathy. We found standardized mean differences in favor of the exercise group of 0.27–2.00 for static balance, Berg Balance Scale, Timed-up-and-go-test, nerve conduction velocity of peroneal and sural nerve as well as for HbA1c in patients with DPN, and standardized mean differences of 0.43–0.75 for static balance, quality of life, and neuropathy-induced symptoms in patients with CIPN.&#x0D; Conclusion&#x0D; For DPN, evidence-based recommendations can now be made, suggesting a combination of endurance and sensorimotor training to be most beneficial. For patients with CIPN, sensorimotor training remains the most crucial component. For all other neuropathies, more high-quality research is needed to derive evidence-based recommendations. Overall, it seems that sensorimotor training has great potential to target most neuropathies and combined with endurance training is therefore currently the best treatment option for neuropathies.

Importance of Vitamin D Status and Nerve Conduction in Pediatric Cystic Fibrosis Patients

AbstractCystic fibrosis is one of the most common inherited diseases. It presents with recurrent respiratory infections, pancreatic insufficiency, and growth retardation. Neurological involvement becomes more common as life expectancy increases. Chronic hypoxia, impaired glucose intolerance, autoimmune mechanisms, vasculitis changes, and micronutrient deficiencies seem to cause neuropathy in cystic fibrosis. This study was aimed to investigate peripheral neuropathy in pediatric cystic fibrosis patients. Twenty-one cystic fibrosis patients and 19 healthy control subjects between the ages of 7 and 17 years were included. Their nerve conduction study results and laboratory investigations were analyzed. Participants were classified into four groups; 1. Cystic fibrosis with vitamin D deficiency, 2. Cystic fibrosis with normal vitamin D levels, 3. Healthy subjects with vitamin D deficiency, 4. Healthy subjects with normal vitamin D levels. We found statistically significantly lower sensory median nerve sensorial nerve action potential, sensorial sural nerve conduction velocity, and motor peroneal nerve compound motor action potential in cystic fibrosis patients with vitamin D deficiency than in other cases. We also found that the main difference between cystic fibrosis and control groups was especially in patients with low vitamin D levels. Nerve damage starts at an early age, especially in cystic fibrosis patients especially those with vitamin D deficiency. Electrophysiological evaluation to assess neuropathy is important even in asymptomatic patients. Prevention of hypovitaminosis D is important to prevent neuropathy in cystic fibrosis patients.

Electrophysiological profile of serum vitamin B12 levels, correlation with serum methylmalonic acid levels, and determination of subclinical peripheral nerve involvement

Background/Aim: Vitamin B12 is essential for normal neural conduction in peripheral nerves. This study aimed to investigate the electrophysiological profile for varying degrees of serum B12 levels and to determine whether a correlation existed between electrophysiological profiles and serum methylmalonic acid (MMA) levels. Also, determination of subclinical peripheral nerve involvement with cold administration was planned in serum B12 levels. Methods: A total of 101 (63 females, 38 males) subjects with known serum vitamin B12 levels were selected randomly from the neurology outpatient clinic for this study. The subjects were divided into three groups based on the serum total Vitamin B12 levels: (1) B12 deficiency (&lt;126 pg/mL), (2) low B12 (126-250 pg/mL), and (3) normal B12 (250–500 pg/mL). Serum MMA and nerve conduction studies (NCS) were assessed and compared between the three groups. After the cooling procedure was applied to the ulnar and sural nerves, NCS was repeated. Results: There were 13 subjects in the B12 deficiency group, 44 subjects in the low B12 group, and 44 subjects in the normal group. We found that ulnar sensory nerve action potential amplitudes were significantly decreased (P = 0.009), ulnar F latency (P = 0.003; P &lt; 0.001)) was prolonged, and peroneal combined muscle action potential amplitudes decreased (P = 0.026) in the B12 deficiency when compared with the low and normal B12 groups. Sural nerve amplitude and conduction velocities were found to be significantly abnormal after the cold application in all groups (P &lt; 0.001). The increase in sural nerve sensory nerve amplitude potentials (SNAP) amplitudes was higher in the B12 deficiency group than in the other groups. Mean serum MMA levels were high in all groups. A correlation of nerve conduction study (NCS) changes with serum vitamin B12 and MMA was not observed in the groups after cold application. Conclusion: Vitamin B12 deficiency may cause subclinical sensorial and motor axonal nerve conduction changes. Nerve conduction changes may not always reach pathological values based on electrophysiological studies but may be detected after cooling administration even in the normal serum B12 levels. A correlation between serum MMA and vitamin B12 levels was found. Therefore, serum levels of vitamin B12, which is important for nerve conduction, should be carefully evaluated in clinical practice.

Lower Visceral Fat Area in Patients with Type 2 Diabetic Peripheral Neuropathy.

There is preliminary evidence that visceral fat area (VFA) was associated with the presence of type 2 diabetic peripheral neuropathy (DPN) in the Korean population; however, no studies have reported the association in Chinese population. The purpose of this study was to explore the possible correlation of VFA with DPN in such a population. A total of 2498 hospitalized patients with type 2 diabetes mellitus (T2DM) undergone VFA measurement, and were divided into DPN group (n=900) and non-DPN group (n=1594). The association of VFA with the presence of DPN was evaluated by correlation and multiple logistic regression analyses, generalized additive model with a smooth curve fitting, and receiver operating characteristic (ROC) curve analysis. The VFA was significantly lower in the DPN group than in the non-DPN group (P < 0.001). VFA was significantly and positively associated with sural nerve conduction velocity (SNCV) and amplitude potential (SNAP) and negatively associated with the presence of DPN (all P< 0.001); there was no significant difference in the curve fitting (P = 0.344). Multivariate logistic regression analysis showed that the risk of presence of DPN decreased progressively across the VFA quartiles (P for trend < 0.001) and was significantly lower in patients in the highest VFA quartile than in those in the lowest quartile (OR: 0.382, 95% CI 0.151-0.968, P< 0.001) after multivariate adjustment. The ROC analysis revealed that the best cut-off value of VFA for predicting the presence of DPN was 50.5cm2 (sensitivity 84.40%; specificity 34.00%). These results suggest that lower VFA level may be associated with increased risk of the presence of DPN in T2DM patients.

Corneal nerve and nerve conduction abnormalities in children with type 1 diabetes.

In vivo corneal confocal microscopy (CCM) is a novel, rapid, and non-invasive technique that identifies early small fiber damage and can predict the progression and development of clinical neuropathy in adults with type 1 diabetes. However, its usefulness in children is not well established. This study compared corneal confocal microscopy with neuropathic symptoms, signs, and objective measures of neuropathy for the diagnosis of diabetic neuropathy in children with type 1 diabetes. A total of 83 children with type 1 diabetes and 83 healthy participants of similar age underwent assessment of neuropathy symptoms, signs, nerve conduction studies, quantitative sensory and autonomic function testing, and in vivo CCM. Only of 3/83 (4%) children with type 1 diabetes had subclinical neuropathy. However, corneal nerve fiber density (p=0.001), branch density (p=0.006), fiber length (p=0.002), tibial motor nerve amplitude and conduction velocity, and sural sensory nerve amplitude and conduction velocity (all p < 0.004) were lower in participants with type 1 diabetes than in the controls. Vibration, cooling, and warm perception thresholds and deep breathing heart rate variability were not found to be different (all p > 0.05) between children with type 1 diabetes and healthy controls. Multivariate regression analysis identified a possible association between body mass index and decreased corneal nerves. Decreased corneal nerves and abnormal nerve conduction were found in children with type 1 diabetes. CCM may allow rapid objective detection of subclinical diabetic neuropathy in children and adolescents with type 1 diabetes.

The Peripheral Neuropathy Prevalence and Characteristics Are Comparable in People with Obesity and Long-Duration Type 1 Diabetes

IntroductionPeripheral neuropathy is reported in obesity even in the absence of hyperglycaemia.ObjectiveTo compare the prevalence and characterise the phenotype of peripheral neuropathy in people living with obesity (OB) and long-duration type 1 diabetes (T1D).Patients and MethodsWe performed a prospective cross-sectional study of 130 participants including healthy volunteers (HV) (n = 28), people with T1D (n = 51), and OB (BMI 30–50 kg/m2) (n = 51). Participants underwent assessment of neuropathic symptoms (Neuropathy Symptom Profile, NSP), neurological deficits (Neuropathy Disability Score, NDS), vibration perception threshold (VPT) and evaluation of sural nerve conduction velocity and amplitude.ResultsPeripheral neuropathy was present in 43.1% of people with T1D (age 49.9 ± 12.9 years; duration of diabetes 23.4 ± 13.5 years) and 33.3% of OB (age 48.2 ± 10.8 years). VPT for high risk of neuropathic foot ulceration (VPT ≥ 25 V) was present in 31.4% of T1D and 19.6% of OB. Participants living with OB were heavier (BMI 42.9 ± 3.5 kg/m2) and had greater centripetal adiposity with an increased body fat percentage (FM%) (P < 0.001) and waist circumference (WC) (P < 0.001) compared to T1D. The OB group had a higher NDS (P < 0.001), VAS for pain (P < 0.001), NSP (P < 0.001), VPT (P < 0.001) and reduced sural nerve conduction velocity (P < 0.001) and amplitude (P < 0.001) compared to HV, but these parameters were comparable in T1D. VPT was positively associated with increased WC (P = 0.011), FM% (P = 0.001) and HbA1c (P < 0.001) after adjusting for age (R2 = 0.547). Subgroup analysis of respiratory quotient (RQ) measured in the OB group did not correlate with VPT (P = 0.788), nerve conduction velocity (P = 0.743) or amplitude (P = 0.677).ConclusionThe characteristics of peripheral neuropathy were comparable between normoglycaemic people living with obesity and people with long-duration T1D, suggesting that metabolic factors linked to obesity play a pivotal role in the development of peripheral neuropathy. Further studies are needed to investigate the mechanistic link between visceral adiposity and neuropathy.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12325-022-02208-z.

Acupuncture improves chemotherapy-induced neuropathy explored by neurophysiological and clinical outcomes – The randomized, controlled, cross-over ACUCIN trial

BackgroundChemotherapy-induced peripheral neuropathy (CIPN) is recognized as the second commonest side effect after chemotherapy. Besides neurological deficits and pain, it is a potential reason for terminating chemotherapy. Effective curative treatments of neurodegeneration are lacking. Hitherto, no randomized controlled study used nerve conduction studies (NCS), the gold standard diagnostic tool for peripheral neuropathy, as the primary outcome parameter for evaluating acupuncture for CIPN, which can also measure structural changes. MethodsThe study was carried out at the HanseMerkur Center for TCM at the University Medical Center, Hamburg-Eppendorf. Sixty patients with CIPN were included in the study after physical examination, subjective evaluation and quantitative evaluation by NCS. Subsequently, the patients were randomly assigned to Group 1 (30 patients), which received, in the first period, needle acupuncture and to Group 2 (30 patients), which was assigned to the waiting list in the first period. Group 1 received a standard 10-week bilateral treatment of ST34 (Liangqiu), EX–LE12 (Qiduan) and EX–LE8 (Bafeng). After 14 weeks, both groups were re-evaluated. Using a cross-over design, the patients of Group 2 received the same treatment procedure as Group 1 in the first period. Patients of Group 1 were assigned to the waiting list for the second period. After 28 weeks both groups were re-evaluated. Wilcoxon test was used as a pre-test to rule out carryover effects and to test for differences between acupuncture and the waiting list. Group assignment was not exposed to the statistician and the neurologist. ResultsSural sensory nerve amplitude, and sural nerve conduction velocity, were significantly improved (p < 0.01, effect size (f) 0.55 and 0.49) compared to measurements in the waiting period. Change of NCS of the tibial nerve did not significantly differ in group comparison. Patients reported subjective improvement during acupuncture treatment superior to the waiting period for burning pain, cramps, numbness, frequency of symptoms (all p < 0.01) and unsteadiness of gait (p < 0.05). On physical examination, blind walking, heel-to-toe walking, distal pallhypesthesia (both p < 0.01), and the neuropathy deficit score (p < 0.05) were significantly improved during acupuncture treatment compared to the waiting period. ConclusionAcupuncture can enhance structural regeneration in CIPN as measured by NCS, which is manifested in subjective improvement and neurological findings.

Physical Exercise as Treatment for Type 2 Diabetes Distal Symmetric Polyneuropathy: A Systematic Review of Randomized and Controlled Studies

Pharmaceuticals targeting the pathogenesis of diabetic distal symmetric polyneuropathy have all failed in clinical trials, limiting recourse to palliative treatments. The American Diabetes Association regards the effectiveness of glycemic control and lifestyle modification therapies on diabetic neuropathies as inconclusive. The objective of this research was to determine if and how physical exercise influences distal symmetric polyneuropathic severity in type 2 diabetes patients. Embase, MEDLINE, and Google Scholar were searched to collect randomized and controlled studies published between January 1, 2012 and April 20, 2020. Titles had to mention diabetes, physical exercise of any type or lifestyle interventions in general, and neuropathy. Abstracts had to indicate satisfaction of PICOS criteria, whereas full-text reviews had to be fully confirmatory. Extracted data was thematically synthesized based primarily on relationships between exercise interventions and effects on distal symmetric polyneuropathic severity outcomes in type 2 diabetes patients. Qualitative analysis scoring criteria objectively mirrored PICO except for the bias and limitation score component, which assessed common markers of validity for randomized trials (as specified in the PRISMA statement). Database searches yielded 379 unique records, 15 of which passed eligibility screening. Thematic synthesis supported exercise as an ameliorative treatment of type 2 diabetes distal symmetric polyneuropathy through improved Michigan Diabetic Neuropathy Scores and increased sural sensory nerve conduction velocity, though efficacy may be limited by neuropathic severity. This is the first systematic review to acquire these results, and to do so within the context of neuropathic severity. This review protocol is registered on PROSPERO (CRD42020181211) at https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020181211

Exercise and Neuropathy: Systematic Review with Meta-Analysis.

Peripheral neuropathies are a prevalent, heterogeneous group of diseases of the peripheral nervous system. Symptoms are often debilitating, difficult to treat, and usually become chronic. Not only do they diminish patients' quality of life, but they can also affect medical therapy and lead to complications. To date, for most conditions there are no evidence-based causal treatment options available. Research has increased considerably since the last review in 2014 regarding the therapeutic potential of exercise interventions for patients with polyneuropathy. Our objective in this systematic review with meta-analysis was to analyze exercise interventions for neuropathic patients in order to update a systematic review from 2014 and to evaluate the potential benefits of exercise on neuropathies of different origin that can then be translated into practice. Two independent reviewers performed a systematic review with meta-analysis according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Inclusion criteria according to the PICOS approach were: neuropathic patients, exercise interventions only, an inactive or non-exercising control group, and solely randomized controlled trials with the following outcome parameters: neuropathic symptoms, balance parameters, functional mobility, gait, health-related quality of life, and HbA1c (glycated hemoglobin). A total of 41 randomized, controlled trials met all inclusion criteria, 20 of which could be included in the quantitative analysis. Study quality varied from moderate to high. Current data further support the hypothesis that exercise is beneficial for neuropathic patients. This is best documented for patients with diabetic peripheral neuropathy (DPN) (27 studies) as well as for chemotherapy-induced peripheral neuropathy (CIPN) (nine studies), while there are only few studies (five) on all other causes of neuropathy. We found standardized mean differences in favor of the exercise group of 0.27-2.00 for static balance, Berg Balance Scale, Timed-up-and-go-test, nerve conduction velocity of peroneal and sural nerve as well as for HbA1c in patients with DPN, and standardized mean differences of 0.43-0.75 for static balance, quality of life, and neuropathy-induced symptoms in patients with CIPN. For DPN, evidence-based recommendations can now be made, suggesting a combination of endurance and sensorimotor training to be most beneficial. For patients with CIPN, sensorimotor training remains the most crucial component. For all other neuropathies, more high-quality research is needed to derive evidence-based recommendations. Overall, it seems that sensorimotor training has great potential to target most neuropathies and combined with endurance training is therefore currently the best treatment option for neuropathies. (PROSPERO 2019 CRD42019124583)/16.04.2019.

A Comparative Study Analysis of Lower Limb and Upper Limb Conduction Velocity among Asymptomatic Patients of Type 2 Diabetes Mellitus

Objectives: Diabetes Mellitus is worldwide disease and diabetic peripheral neuropathy (DPN) is one of the most prevalent micro-vascular complication seen during the progress of disease. Frequently there is subclinical involvement seen for peripheral nerve functions which is revealed on nerve conduction study. Present study aims to assess nerve conduction velocity changes among asymptomatic patients with type 2 diabetes mellitus. Materials and Methods: Total 60 subjects were included for the study, 30 of them were of type 2 diabetes mellitus on regular treatment with disease duration of less than 5 years and asymptomatic for neuropathy and 30 were controls. All the participants were subjected to nerve conduction studies. Results: Nerve Conduction Velocity (NCV) of sural sensory nerve was found to be significantly decreased in diabetic patients as compared to controls. Conclusion: Sensory NCV was significantly decreased in the sural nerve compared to upper limb sensory nerves which suggests that long nerves are more prone to neuropathic changes even in asymptomatic diabetic patients.

Updates in diabetic neuropathy: A call for new diagnostic and treatment approaches.

Diabetic polyneuropathy (DPN) is a serious complication of both type 1 and type 2 diabetes. The major clinical manifestations of DPN are neuropathic pain, diabetic foot (which is associated with ulcers, gangrene, and amputation), and autonomic neuropathy. Diabetic sensorimotor peripheral neuropathy (DSPN) is the most common form of DPN and affects approximately 50% of people with type 1 or 2 diabetes during their lifetime (1) . Despite its major clinical impact, DPN remains underdiagnosed and undertreated. To reduce the burdens of DPN, there is an urgent need to develop both novel diagnostic procedures that enable to improve the early detection of the disease and new treatments that address multiple mechanistic pathways (Figure) (2) .

O-NE004. Distinguishing GBS with treatment-related fluctuations from acute-onset CIDP: A neurophysiological and ultrasonographic perspective

Introduction . Distinguishing Guillain-Barré syndrome (GBS) with treatment-related fluctuations (TRF) from acute-onset chronic inflammatory demyelinating polyneuropathy (A- CIDP) in the early phase can be challenging. Distinguishing features in clinical aspect have been reported previously. We aim to identify the neurophysiological and ultrasonographic features that might differentiate between patients with GBS-TRF and A-CIDP. Methods . Patients with GBS-TRF and A-CIDP were identified from an existing cohort of GBS patients presenting to University Malaya Medical Centre, Kuala Lumpur, Malaysia from 2011 to 2019. The clinical, neurophysiological and nerve ultrasound data were recorded and analysed. Results . Five GBS-TRF (mean age 42 ± 23 years old) and five A-CIDP (mean age 66 ± 13 years old) patients were included. The mean time to first neurological deterioration was significantly longer in the A-CIDP patients compared to GBS-TRF (11 vs 5 weeks; p = 0.028). Based on two sets of nerve conduction studies (NCS), both GBS-TRF and A-CIDP patients fulfilled the electrodiagnostic criteria for demyelination. At first study, A-CIDP patients had significantly prolonged ulnar minimal F-wave latencies (40.7 vs 28.6 ms; p = 0.020) and slower tibial nerve motor conduction velocities (32.1 vs 38.0 m/s; p = 0.050) when compared to GBS-TRF. The sural nerve conduction velocities were slower in A-CIDP compared to GBS-TRF during the second study (26.3 vs 41.4 m/s; p = 0.015). The sural potentials were also more likely to be unrecordable in A-CIDP patients in the second study. On nerve ultrasound, A-CIDP patients had significantly larger cross-sectional area of the ulnar nerve at the wrist (7 vs 5 mm 2 ; p = 0.039), forearm (8 vs 5 mm 2 ; p = 0.025), below elbow (9 vs 6 mm 2 ; p = 0.031) and above elbow (9 vs 7 mm 2 ; p = 0.037) compared to GBS-TRF patients. Conclusion . Other than distinguishing clinical features, we found that there were neurophysiological and ultrasonographic features that can be useful in differentiating between GBS-TRF and A-CIDP.

Nerve conduction studies (NCS) and electromyography (EMG) O-NE001. Correlation of nerve conduction velocity with body fat mass and oxidative stress markers in type 2 diabetic neuropathy patients

Introduction . Diabetic peripheral neuropathy (DPN) is the most common but least recognised and understood long term complication of type 2 diabetic patients (T2DM). There is a close association between obesity and type 2 diabetes as well as its complications. Nerve conduction study is an important non-invasive diagnostic modality used in the detection of diabetic peripheral neuropathy. Obesity is associated with increased oxidative stress and lipid peroxidation is thought to play a crucial role in the development of diabetic neuropathy. The aim of this study is to see the correlation of nerve conduction velocity parameters viz nerve conduction velocity and nerve conduction amplitude with the total body fat mass and oxidative stress markers. Methods . The study included 90 type 2 diabetes patients with clinically suggestible symptoms of diabetic peripheral neuropathy (DPN). 50 type 2 diabetic subjects without peripheral neuropathy served as control. Total body fat mass was measured using bioelectric impedance analysis. Oxidative stress markers viz total antioxidant capacity and malondialdehyde were measured using elisa kit. Nerve conduction study both motor and sensory was carried out in relevant nerves. Results . Serum levels of total antioxidant capacity and super oxide dismutase were significantly decreased in type 2 diabetic with neuropathy as compared to the ones without neuropathy. Serum levels of malondialdehyde, on the other hand, was significantly elevated. Motor nerve conduction velocity (MNCV) of ulnar and common peroneal nerve and sensory nerve conduction velocity of ulnar and sural showed a significantly decreased conduction velocity as compared to control. The total body fat mass showed a significant negative correlation with the motor conduction velocity of median, posterior tibial and sensory conduction velocity of median and sural nerve. Conclusion . The nerve conduction velocity test and total body fat mass evaluation is a cost- effective tool for earlier detection of neuropathy in type 2 diabetes patient.

Electrophysiological Study of the Tibial Nerve Across the Tarsal Tunnel in Distal Symmetric Diabetic Polyneuropathy.

The aim of the study was to demonstrate abnormalities of motor conduction of the tibial nerve across the tarsal tunnel in type 2 diabetes. One hundred twenty-four consecutive patients (mean age = 66.6 yrs, 62.1% male) with distal symmetric diabetic polyneuropathy clinically diagnosed were prospectively enrolled. Nerve conduction studies of deep peroneal, tibial, superficial peroneal, medial plantar, and sural nerves and standard needle electromyography in the lower limbs were performed. Demographic, anthropometric, and clinical findings were collected. Motor conduction velocity of the tibial nerve across tarsal tunnel was slowed in 60.5% of patients; another 4% showed conduction block across tarsal tunnel without reduction of motor conduction velocity. Overall percentage of abnormalities across tarsal tunnel (64.5%) exceeds that of the sensory conduction velocities of proximal sural and superficial peroneal nerves. Abnormal tibial motor conduction velocity across tarsal tunnel represents the most common abnormality among all motor nerve conduction study parameters and significantly correlates with hemoglobin level, diabetic neuropathic index score, and diabetic complications frequency. Tibial conduction abnormalities across tarsal tunnel are the most sensitive motor parameter in distal symmetric diabetic polyneuropathy, second only to conduction abnormalities of sensory/mixed distal nerves of the feet. The use of nerve conduction studies across tarsal tunnel of the tibial nerve may be useful in the electrophysiological protocol to confirm the diagnosis of distal symmetric diabetic polyneuropathy.

The silent occurrence of cerebral small vessel disease in nonelderly patients with type 2 diabetes mellitus.

The prevalence of cerebral small vessel disease (SVD) increases in elderly patients with type 2 diabetes (T2DM), exacerbating cognitive decline. However, the prevalence and the severity of SVD in dementia-free nonelderly T2DM patients were largely unknown. Our primary aim is to investigate SVD in such patients, with a specific focus on the correlation between SVD and diabetic peripheral sensorimotor polyneuropathy (DSP). We recruited 180 young and middle-aged subjects without cognitive impairment (106 with T2DM, 74 controls). Signs of cerebral SVD on magnetic resonance image were investigated, and the overall SVD burden was evaluated by a combined score. Patients with T2DM underwent further detailed DSP assessment. Regression models were used to investigate the association of SVD with the presence of T2DM, and the associations of the prevalence and severity of SVD and DSP were also explored in patients with T2DM. The prevalence of microbleeds and overall burden of SVD were significantly higher in T2DM patients than in the controls. Further, the presence of DSP related to an increased risk of SVD after adjustment in diabetic group. Moreover, Toronto Clinical Scoring System values were positively associated with the increased SVD scores, and bilateral sural sensory nerve conduction velocities were negatively associated with increasingly severity of SVD scores. The current findings extended the increasing prevalence of SVD to dementia-free nonelderly patients with T2DM, suggesting that the time for cognitive screening and prevention might be moved forward in T2DM patients, especially for those with DSP.