Sensory Nerve Conduction Studies Research Articles

Elucidation of peripheral nerve myelination by bimodal waveform analysis

PurposeAs the myelin sheath of the peripheral nerves is immaturely developed in children, a bimodal waveform may be evoked when sensory nerve conduction studies are performed in them. However, there has been no study regarding the relationship between age and the frequency of appearance of the bimodal waveform or the inter-peak latency. Herein, we examined how the bimodal waveform changes with age. MethodsA total of 218 sensory nerves (109 median and 109 ulnar nerves) in 86 children (0 to 15 years old) were analyzed. The frequency of the bimodal waveform and the distance-corrected inter-peak latency were examined with antidromic sensory nerve conduction studies of the upper limbs on proximal stimulation. ResultsThe frequency of bimodal waveforms and distance-corrected inter-peak latency decreased with age. Analysis of the slope line of the scatter plot demonstrated that the bimodal waveform was present until the age of 15–16 years. ConclusionThe bimodal waveform of sensory nerves faded with growth. Given that development-associated temporal dispersion is considered to be the cause of the differences in the bimodal waveform, our findings suggest that the underlying cause of the bimodal waveform is an immature myelin sheath, which may not be fully developed until the age of 15–16 years.

The effect of a 9-month hybrid intradialytic exercise training program on nerve conduction velocity parameters in patients receiving hemodialysis therapy.

Neurological complications such as peripheral neuropathy are very common in the end-stage renal disease (ESRD) patients, occurring in 60-80% of this specific population. The aim of the present study was to examine whether a 9-month hybrid intradialytic exercise training program could alter motor and sensory nerve conduction study (NCS) parameters in hemodialysis population. Seventeen stable patients undergoing HD with no clinical evidence of uremic polyneuropathy were included in the study (15M/2F, 59 ± 13.7years). All patients completed a 9-month supervised exercise training program composed of both aerobic cycling and resistance training (hybrid) during HD. Functional capacity was assessed by a battery of tests, while pain levels and fatigue profile were assessed via validated questionnaires. Motor and sensory NCS on bilateral median, ulnar, peroneal and tibial nerves as well as F-wave were assessed using a full neurographic electromyography (EMG) assessment. After the 9-month exercise training intervention, exercise capacity was increased by 65% and functional capacity by an average of 40%. The neurological assessment showed that conduction velocity from tibial and peroneal nerves was improved by 3.7% and 4.2%, respectively, while tibial F-wave latency and peroneal and sural nerve distal latency were significantly improved by 4.2%, 4.9% and 10%, respectively. Fatigue and pain were improved after the exercise intervention while fatigue score was positively correlated with conduction velocity and amplitude values. The results of the current study demonstrate that 9-month hybrid exercise training induces beneficial effects on both sensory and motor NCS parameters, improving conduction velocity and F-wave latency. Improvements in neural activity were accompanied by changes in fatigue score and pain-related aspects. The parallel improvement in motor nerve conduction velocity and its correlations with functional tests supports the hypothesis that exercise could be beneficial for preventing a decline in neural function in HD patients.

P.102 Role of interdigital sensory nerve conduction study as a noninvasive approach for early diagnosis of diabetic peripheral neuropathy

Background: Diabetes mellitus is a common cause of polyneuropathy. Despite numerous diagnostic tools such as routine electrophysiologic procedures, its early detection is challenging. This study compares a distal electrodiagnostic technique, with conventional approaches to investigate its role in confirming early polyneuropathy. Methods: Thirty-one symptomatic diabetic outpatients and 23 asymptomatic nondiabetic subjects were included in our study. We performed nerve conduction studies on the dorsal sural, medial plantar, and digital branches of the interdigital nerves to toes I, II, and III (as a new antidromic technique). All techniques were applied with the surface stimulator and pick-up electrodes. Results: Only 9 (29%) of patients had impaired routine NCSs. Interestingly, the results of interdigital nerve studies were abnormal in 17 out of 22 patients with normal routine NCSs. Also, 11 and 13 subjects had impaired medial plantar and dorsal sural nerves conduction studies, respectively. According to this method, the prevalence of detectable diabetic neuropathy increased from 46% to 83%. Conclusions: The digital sensory branches can be easily evaluated with the new antidromic SNAP technique for the early diagnosis of diabetic polyneuropathy, especially in presymptomatic and subclinical neuropathies. This method is simple, non-invasive, sensitive, and reproducible. There is no need for needle electrodes or averaging techniques.

Implications of median sensory study to the thumb and deltoid/biceps motor unit recruitment on identifying C6 root avulsion in upper neonatal brachial plexus palsy.

Anatomic representation suggests that a median sensory nerve conduction study recording the thumb (median D1 NCS) may effectively assess upper neonatal brachial plexus palsy (NBPP). We sought to determine the feasibility of technique, establish reference data, and assess its ability to: (a) identify focal upper plexus lesions; and (b) identify C6 root avulsion. In a secondary analysis, we explored the association between absence/presence of motor unit action potentials (MUAPs) during needle electromyography (EMG) of the deltoid and biceps brachii muscles and C6 avulsion status. A retrospective chart review was performed of surgical patients with severe upper NBPP who ultimately underwent surgical reconstruction (between 2017 and 2020). Median D1 sensory nerve action potential (SNAP) amplitude ranges were determined in affected and contralateral limbs and analyzed by C6 root avulsion status. Also, presence/absence of MUAPs during EMG of the deltoid and biceps brachii was compared between C6 avulsion patients and controls. Thirty-eight patients were included in our analysis. A median D1 NCS study was readily performed, showing a contralateral limb mean amplitude of 27.42 μV (range, 3.8-54.7μV). Most patients had a low ipsilateral median D1 SNAP amplitude, regardless of C6 avulsion status. Detectable MUAPs in either deltoid or biceps brachii on EMG were atypical in C6 root avulsion. The median D1 NCS identifies upper NBPP, but does not distinguish C6 avulsions from post-ganglionic lesions, likely due to the frequent co-occurrence of post-ganglionic axonal disruption. The presence of MUAPs on deltoid/biceps brachii EMG suggests C6 avulsion is unlikely.

Different patterns of sensory nerve involvement in chronic inflammatory demyelinating polyneuropathy subtypes.

Among subtypes of chronic inflammatory demyelinating polyneuropathy (CIDP), different immune pathophysiologies have been proposed. In this study, sensory nerve conduction studies were compared among clinical subtypes to attempt to better understand the underlying pathophysiology. A total of 138 patients with CIDP was classified into clinical subtypes: typical CIDP (N=68), multifocal CIDP (N=27), or other (N=2). Patients with immunoglobulin M (IgM) neuropathy anti-myelin-associated glycoprotein neuropathy (MAG; N=19) were also included as disease controls. Sensory nerve action potentials (SNAPs) were recorded in the median, ulnar, and superficial radial and sural nerves. SNAP amplitudes (P < .05) and conduction velocities (P < .01) in the median nerve and conduction velocities (P < .05) in the ulnar nerve were lower in typical CIDP than in multifocal CIDP, whereas those in the radial and sural nerves were comparable in each group. Low median and normal sural SNAP amplitudes were more common in typical CIDP (P < .005) than in multifocal CIDP, suggesting predominant involvement at terminal portions of the nerves. Terminal portions of sensory nerves are preferentially affected in typical CIDP compared with multifocal CIDP. These findings might be partially explained by the hypothesis of antibody-mediated demyelination in typical CIDP at the regions where the blood-nerve barrier is anatomically deficient, whereas multifocal CIDP predominantly affects the nerve trunks, largely due to cell-mediated demyelination, with disruption of the blood-nerve barrier.

In Carpal Tunnel Syndrome, Sensory Nerve Conduction Velocities Are Worst in the Middle Finger Than in the Index Finger.

Although the index finger is generally used for sensory nerve conduction study in cases of carpal tunnel syndrome, there are reports that the middle finger should be used. The purpose of this study was to compare the results of sensory nerve conduction studies of the index finger and middle finger in patients with carpal tunnel syndrome. Among the 120 hands of 93 patients who were diagnosed with carpal tunnel syndrome and underwent carpal tunnel release surgery at our hospital, 54 hands of 48 patients who showed waveforms in sensory nerve conduction studies both index and middle fingers were included. 6 hands of 6 patients who showed no waveform in the index or middle finger, and 60 hands of 39 patients who showed no waveform in both index and middle finger were excluded. The subjects were 14 males and 34 females, and their ages were 66.2 years. The preoperative sensory nerve action potential (μV) and sensory nerve conduction velocity (m/s) of the index and middle fingers were tested using Wilcoxon's signed rank test. Spearman's rank correlation coefficient was also calculated for the results of the index and middle fingers. Sensory nerve action potentials were 2.0 in the index finger and 1.8 in the middle finger, with significantly lower in the middle finger. Sensory nerve conduction velocity was 30.1 in the index finger and 27.2 in the middle finger, with significantly lower in the middle finger. The correlation coefficients of sensory nerve action potentials and conduction velocities between the index finger and middle finger were 0.82 and 0.96, respectively, both of which showed a significant correlation. The results of the sensory nerve conduction studies of the middle finger were significantly worse than those of the index finger in cases of carpal tunnel syndrome. In addition, there was a strong correlation between the results of the index finger and the middle finger. The results of this study suggest that the nerve bundle to the middle finger may be more strongly affected than the nerve bundle to the index finger in cases of carpal tunnel syndrome.

Reference Standards for Nerve Conduction Studies of Individual Nerves of Lower Extremity With Expanded Uncertainty in Healthy Korean Adults

Objective To develop a set of reference standards for tibial motor, common peroneal motor, sural sensory, and superficial peroneal sensory nerve conduction studies (NCSs) with expanded uncertainty in a healthy Korean population.MethodsStandardized procedures were conducted for individual lower extremity NCSs of 199 healthy participants in their 20s (n=100) and 50s (n=99). Mean values and expanded uncertainties for parameters were analyzed with thorough consideration of multiple uncertainty factors under the International Guide to the Expression of Uncertainty in Measurement. In addition, side-to-side differences in onset latency, amplitude, and nerve conduction velocity (NCV) were analyzed.ResultsMean (reference range) for distal onset latency, baseline to negative peak amplitude, NCV of tibial motor nerve in males in their 20s were 4.3 ms (3.1–5.4 ms), 7.1 mV (3.4–10.9 mV), and 50.7 m/s (42.2–59.3 m/s), respectively; sural sensory nerve baseline to negative peak amplitude in males in their 20s was 21.7 μV (8.3–35.2 μV). Including the aforementioned data, we present a vast dataset of normative mean values and expanded uncertainties for NCSs of the leg in a healthy Korean population. Furthermore, upper limits for normal side-to-side differences for onset latency, amplitude, and NCV of each nerve are suggested.ConclusionTo our knowledge, this is the first study to present the reference standards of leg NCSs with consideration for multifactorial uncertainties in an Asian population. We expect these results to help practitioners make reliable and reproducible clinical decisions.

OC08: A-wave serves as a diagnostic measure for demyelinating polyneuropathies

A-wave occurs in various neurologic conditions and occasionally, also in healthy elderly subjects, mainly in the tibial nerve. We designed this study to document types of neurological disorders preferentially associated with the occurrence of A-wave and multiple A-waves. The study consists of a retrospective review of clinical and electrophysiologic data in 610 patients. They comprised 74 ALS, 123 radiculopathy, 206 CTS, 100 DPN, 51 GBS and 56 CIDP patients as well as 127 healthy subjects. We divided all patients into simple A-wave, multiple A-wave and non A-wave groups and analyzed their association with gender, age, sensory nerve conduction studies (SNCS) and clinical diagnosis, using R software decision-tree and Random Forest analysis. Specifically, we compared frequencies of median, ulnar and tibial nerve A-wave and multiple A-waves in DPN, GBS and CIDP patients. A-wave group had more older age, male gender, abnormal SNCS and patients diagnosed as DPN, GBS or CIDP than non A-wave group. Compared with simple A-wave group, multiple A-waves group had more absent SNAP. In simple-A group, DPN emerged as the most common diagnosis whereas in multiple-A group, GBS ranked the highest. Compared to healthy subjects, A-wave occurred more frequently in DPN, GBS and CIDP but not in ALS, radiculopathy or CTS. Tibial nerve A-wave as a whole showed no difference among DPN, GBS and CIDP but multiple A-waves occurred more frequently in the order of GBS > CIDP > DPN. We conclude that A-wave, particularly, multiple A-waves, serve as an early diagnostic measure for acute demyelinating polyneuropathies.

HP38: Neurophysiological assessment of peripheral neuropathies associated with COVID-19

Neurological complications associated with COVID-19 are a significant cause of morbidity, affecting both central and peripheral nervous systems. We aim to assess the electrophysiological features of peripheral nerve injuries (PNI) in patients with COVID-19.Methods: We included 31 patients between March 2020 and April 2021 with a suspected diagnosis of PNI with COVID-19. We performed motor and sensory nerve conduction studies and electromyography (EMG) in the upper and lower extremities.Results: The mean age was 66.8±3.1 years (21 males, 10 females). A 96.7% (30 patients) were admitted to ICU, with a mean stay of 32.9±5.1 days. The neurophysiological examination showed, in descending order: mixed polyneuropathies 22.6% (7 patients), motor axonal polyneuropathies 19.4% (6 patients), sensorimotor axonal polyneuropathies 19.4% (6 patients), peroneal mononeuropathies 12.9% (4 patients), brachial plexopathies 12.9% (4 patients), Guillain-Barré syndrome (GBS) 6.4% (2 patients), Miller Fisher syndrome (MFS) 3.2% (1 patient) and femoral mononeuropathy 3.2% (1 patient).The low amplitude in both motor and sensory conduction studies was the most common neurophysiological finding except in GBS and MFS that showed prolonged distal latency and slow conduction velocity. EMG showed spontaneous activity in all patients.Conclusion: Our study shows the main neuropathy damage related to COVID-19 was critical illness polyneuropathy; however, we must consider mononeuropathies in these patients. There is broad evidence concerning the peripheral nervous system injury as a complication in patients hospitalized by COVID-19, being the neurophysiological tests a valuable tool to assess the peripheral nerve function.

The Significance of Height on Median and Ulnar Nerves Conduction Parameters in Male Subjects

BACKGROUND: Many physiological factors including body temperature, age, height, and gender of the subject affect the nerve conduction parameters (both sensory and motor nerves), so attention should be played for these factors during the evaluation of the nerve function to avoid the false results and later on the false diagnosis of the disease. AIM: The aim of the study was to observe the power of height on median and ulnar nerves conduction parameters (both motor and sensory fibers) in male subjects. METHODS: Seventy healthy males aging 18–60 years were incorporated in the study, for them, motor and sensory nerve conduction study of both ulnar nerve and median nerve was done using NIHON KHODEN machine. RESULTS: There was a significant positive correlation between height and the latency of ulnar sensory nerve (r = 0.29, p = 0.01, and odd’s ratio was 1.6). At the same time, there was significant negative power of height on median and ulnar sensory amplitude (r = −0.32, p = 0.007 and r = −0.28, p = 0.018, respectively). CONCLUSION: The consequence of height on median and ulnar nerve conduction parameters (motor and sensory) is crucial for interpretation the data and later on the diagnosis of the diseases.

Sensory nerve conduction studies in probable painful neuropathy: comparing surface and near-nerve nerve conduction techniques

IntroductionWe compared sensory nerve conduction studies (NCS) using surface and near-nerve recording electrodes in 53 patients with clinical probable painful neuropathy. Our aim was to validate the use of both...

Normative data for ulnar nerve conduction and the influence of gender and height on ulnar nerve conduction velocity in healthy Nigerians.

Background:Despite the usefulness of ulnar nerve conduction studies in identifying disorders of ulnar nerves, there is a lack of normative values for the ulnar nerve in Nigerian population.Objective:The objective of the study was to generate normative values for motor and sensory ulnar nerve conduction studies (NCSs) in Nigerian population and to determine the influence of gender and height on ulnar nerve conduction velocity (NCV).Materials and Methods:A total of 200 healthy volunteers were selected after clinical evaluation to exclude common causes of ulnar neuropathy. We carried out NCS of ulnar nerves on all the healthy volunteers according to a standardized protocol. The NCS parameters included in the final analysis were amplitude, latency, NCV, and f-wave latency. Ethical approval was obtained for the study.Results:The mean ulnar nerve sensory velocity was 55.22 ± 5.67 with 2.5 and 97.5 percentile of 46.9 and 70.1, respectively. The mean latency of the ulnar nerve (sensory) was 2.97 ± 0.62 with 2.5 and 97.5 percentile of 2.00 and 4.52, respectively. The mean amplitude of the ulnar nerve (sensory) was 35.56 ± 9.97 with 2.5 and 97.5 percentile of 15.9 and 57.7, respectively). The ulnar NCV was significantly (P = 0.0202) higher in male. Mild inverse correlation (r = 0.2) was found between ulnar NCV and height of the participants (P = 0.0089).Conclusion:In the Nigerian population, normative values of motor and sensory ulnar nerve conduction parameters are similar to the existing values in the literature. The ulnar NCV appeared to be influenced by height and gender.

Sural-sparing pattern: A study against electrodiagnostic subtypes of Guillain–Barre syndrome

ObjectiveTo study sural-sparing pattern in Guillain–Barre syndrome (GBS) and compare it among GBS’s electrodiagnostic subtypes, classified by two recent criteria. MethodsThis study retrospectively reviewed clinical data and electrodiagnostic studies (EDXs) of 88 GBS patients diagnosed in a tertiary care hospital (2010–2019). ResultsOverall, 79/88 (89.8%) and 36/45 (80%) patients had bilateral sensory nerve conduction studies (NCS) in the first EDX and follow-up EDX, respectively. Sural-sparing occurred in all subtypes (50% overall occurrence rate), most commonly in demyelination. There was no statistically significant difference in sural-sparing occurrence rates between demyelinating and axonal GBS; however, sural-sparing in axonal GBS tended to show a lower number of abnormal upper-limb sensory nerve action potentials (SNAPs) than demyelinating GBS. Shifting between sural-sparing and no sural-sparing occurred in approximately-one-fourth of patients receiving serial studies. Follow-up EDX additionally discovered 20% of all sural-sparing. Unilateral EDX could have omitted up to 30% of sural-sparing. ConclusionsSural-sparing is less obviously manifested in axonal than demyelinating GBS, with respect to the number of affected upper-limb SNAPs. Extended sensory NCS is worth in detecting sural-sparing as a supportive electrodiagnostic GBS feature. SignificanceThis report showed one different character of sural-sparing (number of affected upper-limb SNAPs) between demyelinating and axonal GBS.

High rate of autonomic neuropathy in Cornelia de Lange Syndrome

BackgroundCornelia de Lange Syndrome (CdLS) is a rare congenital disorder characterized by typical facial features, growth failure, limb abnormalities, and gastroesophageal dysfunction that may be caused by mutations in several genes that disrupt gene regulation early in development. Symptoms in individuals with CdLS suggest that the peripheral nervous system (PNS) is involved, yet there is little direct evidence.MethodSomatic nervous system was evaluated by conventional motor and sensory nerve conduction studies and autonomic nervous system by heart rate variability, sympathetic skin response and sudomotor testing. CdLS Clinical Score and genetic studies were also obtained.ResultsSympathetic skin response and sudomotor test were pathological in 35% and 34% of the individuals with CdLS, respectively. Nevertheless, normal values in large fiber nerve function studies.ConclusionsAutonomic nervous system (ANS) dysfunction is found in many individuals with Cornelia de Lange Syndrome, and could be related to premature aging.

Ultrasonographic and electrophysiological outcomes of carpal tunnel syndrome treated with low-level laser therapy: A double-blind, prospective, randomized, sham-controlled study.

Objectives The aim of this study was to investigate the therapeutic effects of low-level laser therapy (LLLT) on clinical, ultrasonographic (US), and electrophysiological findings in carpal tunnel syndrome (CTS).Patients and methods Between January 2015 and August 2015, 42 patients (7 males, 35 females; mean age: 50.4±8.7 years; range, 32 to 65 years) with mild-to-moderate CTS were randomly assigned to one of two groups: active LLLT (therapy group, n=22) 0.8 J/painful point and sham LLLT groups (n=20). Both groups wore neutral wrist orthoses. The patients were evaluated before and after 15 sessions of therapy (670 nm, 4 J/session over the carpal tunnel). Follow-up parameters included the Boston Carpal Tunnel Syndrome Questionnaire (BCTQ) Symptom Severity Scale (SSS), Functional Status Scale (FSS), nerve conduction studies and US evaluation of the median nerve cross-sectional area (CSA), vascularization (via power Doppler), flattening ratio (FR), and palmar bowing of the flexor retinaculum.Results Nocturnal paresthesia improved in both groups; however, pain and patients with a positive Phalen’s test reduced only in the therapy group (p=0.031). The FSS and SSS scores also improved only in the therapy group (p<0.001). Electrophysiologically, median sensory nerve conduction velocities showed a significant improvement only in the therapy group (p=0.002). The CSA, FR, and vascularization of the median nerve showed a significant improvement in the therapy group alone (p<0.001, p=0.048, and p=0.021, respectively).Conclusion Improvements in the signs and symptoms of CTS and hand function, the improvements in sensory nerve conduction studies, and reduction in median nerve CSA, FR and vascularity in the LLLT group can be attributed to the anti-inflammatory and analgesic effects of LLLT. This study provides new US data demonstrating efficacy of LLLT along with a clinical and electrophysiological improvement. The LLLT seems to be an easily applied, non-invasive treatment option.

Peripheral nerve dysfunction and its correlation to interleukin-6 level in obese patients

Abstract Background Obesity is now a worldwide health problem that predisposes to development of numerous complications, one of which is peripheral neuropathy (PN). Elevated interleukin-6 (IL-6) cytokine levels associating the chronic inflammatory state in obesity is thought to play a major role in obesity complications. Methods We conducted a Cross-sectional study on 30 obese patients and 10 matched healthy lean controls. All participants were subjected to full history taking, neurological examination, motor and sensory peripheral nerve conduction studies (NCS). Serum IL-6 levels were assessed using a commercially available ELISA. Laboratory investigations such as glycated haemoglobin, thyroid profile, liver and kidney function tests were done to exclude other known causes of PN. Results Radial, Posterior Tibial and Peroneal nerves had statistically significantly lower motor amplitudes in obese groups compared to control group. Sensory amplitudes of Median nerve showed statistically significant lower values in obese group with PN compared to control group. Conduction velocities (CV) of Ulnar nerve (motor and sensory) and sensory Median nerve showed statistically significant lower CVs in the obese group with PN compared to obese group without PN. Motor Ulnar nerve CV showed highly statistically significant higher velocities in the obese group without PN compared to control group. Posterior Tibial nerve distal motor latencies and Sensory nerve peak latencies of Median nerve had statistically significant higher values in obese group with PN compared to obese group without PN while statistically significant lower sensory peak latencies of Radial nerve were found in obese group without PN compared to control group. Regarding serum IL-6 levels, highly statistically significant higher levels were found in either obese groups when compared to the control group while no statistical significant difference was present between both obese groups and no correlation was found between serum IL-6 and NCS parameters in obese group with PN. Conclusion Our study revealed that despite only 6.667% of our non diabetic obese patients complained of symptoms of PN, by NCS 66.67% of patients were found to have electrophysiological evidence of PN while the remaining 33.33% of patients showed no evidence of PN and no correlation was found between serum IL-6 levels and nerve conduction parameters changes in obese patients diagnosed with PN.

Clinical characteristics and neurophysiology features of amyotrophic lateral sclerosis patients at Sanglah Hospital Denpasar

Background. Amyotrophic lateral sclerosis (ALS) is a one of motor neurons disease. The Incidents in Europe are 2.6 per 100,000 people per year and in the United States, more than 5,600 are diagnosed each year. The death was reportedly 2 per 100,000 people per year. In Sanglah Hospital there are no study that described the characteristics clinical and neurophysiology of ALS at Sanglah Hospital. Objective. To find the characteristics of ALS based on clinical and neurophysiology of ALS at Sanglah Hospital in terms of demography, clinical, Nerve Conduction Studies (NCS) and Electromyography (EMG). Methods. Retrospective descriptive study using medical records of patients in neurology polyclinic at Sanglah Hospital from January until December, 2018. Results. From 14 ALS patients with average age of 47 years old, men and women same amount, high school 71.4%, unemployed 50 %, and married 92.8%. Symptoms first appeared with an average age of 42 years with complaints of lower limb weakness 64.3%. The diagnosis of ALS with the symptom UMN and LMN on bulbar and 2 spinal region 71.4%, and symptom with the UMN and LMN on 3 spinal region 28.6%. Results of motor and sensory NCS were normal, type axonal and mixed neuropathy. Characteristics of EMG were PSW +4, fibrillation +4, MUAP: high amplitude (giant potential), widened duration, polyphasic phase, incomplete IP recruitment in all patients (100%) although in different muscles of the examined patient. Conclusions. Characteristics from 14 patients ALS in 2018 at Sanglah Hospital indicate that patients have a good prognosis.

Enhanced sensory conduction in primary fibromyalgia: a case\u2013control pilot study

BackgroundThis study aimed to test the changes in the conduction properties of peripheral nerves in patients with primary fibromyalgia (FM). Thirty patients with FM and sixteen healthy controls participated in this study. Visual analogue scale (VAS) for pain severity, pain duration, Widespread Pain Index (WPI), Symptom Severity (SS) scale, Hamilton depression rating scale, Taylor’s manifest anxiety scale, and Fibromyalgia Impact Questionnaire (FIQR) were used for measurement of psychiatric comorbidities and quality of life for each patient. Routine motor and sensory nerve conduction studies of both median, ulnar, common peroneal, posterior tibial, and sural nerves were measured for all study participants.ResultsWe found statistically significant increase in Sensory Conduction Velocity (SCV), Sensory Nerve Action Potential (SNAP) amplitude, and decrease in Sensory Latency (SL) in patients with FM compared to controls. There were no significant changes in motor nerve conduction between patients and controls. Regression analysis showed a significant relation between WPI and both SCV and SL especially in nerves of upper limbs. However, no significant relation between SCV and SL and other presumed predictors including VAS for pain severity, pain duration, SS scale, FIQR, and psychiatric comorbidities. Patients with FM suffered more depression and anxiety than controls.ConclusionsWe found enhanced conductivity of the sensory rather than the motor nerves in patients with FM. To our knowledge, this is the first study to describe these sensory changes which may add further evidence of peripheral sensitization in patients with FM.

Frequency of Type-1 Berrettini's Connection in a Neurophysiology Laboratory.

Objective This study aims to estimate the frequency of Berrettini's ulnar-median nerves communication in a neurophysiology laboratory. Materials and Methods A total of 358 hands belonging to patients, both sexes, median age of 58 years, was studied. Antidromic sensory nerve conduction studies of the ulnar nerves, registered in digits III and IV were performed in search of the ulnar-median communication. A Berrettini's percentage was calculated in each communication: [(amplitude SAP digit III/amplitude SAP digit IV) × 100]. Results Ulnar-median nerves communication (Berrettini's branch) was found in 37 hands (10.95%), with a female gender predominance. Bilaterality percentage was low (1.78%). Most communications encountered had a Berretini's percentage between 11 and 50%. Some of them exceeded 100%. Conclusions Electromyographers should routinely search for this nerve communication, especially in those patients undergoing carpal tunnel syndrome or Dupuytren's contracture surgeries.

Age-related sensory neuropathy in patients with spinal muscular atrophy type 1.

Spinal muscular atrophy type 1 (SMA 1) is a devastating motor neuron disorder that leads to progressive muscle weakness, respiratory failure and premature death. Although sensory electrophysiological changes have been anecdotally found in pediatric SMA 1 patients, the age of onset of sensory neuropathy remains unknown. Sensory nerve conduction studies of the median and sural nerves were performed in 28 consecutive SMA 1 patients of different ages. Sensory nerve conduction velocities and sensory nerve action potential (SNAP) amplitudes recorded in these patients were compared with those obtained from 93 healthy subjects stratified by age. SNAP amplitudes decreased with increasing age in the sural and median nerves, without any significant difference between upper and lower limbs. Our data suggest that sural and median nerve SNAP amplitudes are normal in younger patients, while an axonal neuropathy appears in older ones.