Peripheral Nerve Conduction Studies Research Articles

Mutational screening of GDAP1 in dysphonia associated with Charcot-Marie-Tooth disease: clinical insights and phenotypic effects

IntroductionMutations in GDAP1 (Ganglioside-induced differentiation-associated protein 1) gene are linked to Charcot-Marie-Tooth disease (CMT), a Heterogenous group of disorders with multiple phenotypes, characterized by peripheral nerve dysfunction that can lead to vocal cord paralysis and diaphragmatic dysfunction. Main bodyAll three affected children of this chosen family have manifested the same clinical symptoms with progressive weakness, mild sensory impairment, and absent tendon reflexes in their early years. Electrodiagnostic analysis displayed an axonal type of neuropathy in affected patients. Sequencing of the GDAP1 gene was requested for all members of the family. Diagnostic assessments included pulmonary and vocal cord function tests, as well as phrenic and peripheral nerve conduction studies. Pathogenicity of GDAP1 variant p.Pro419Leu with axonal CMT2 and autosomal recessive inheritance was confirmed via in silico analysis. Patients with GDAP1 mutations showed dysphonia, speech difficulties, and the characteristic symptoms of CMT. The severity of symptoms correlated with the presence of a type of GDAP1 mutation. Patients with normal vocal cords and pulmonary function exhibited milder symptoms compared to those with GDAP1 mutations. Our study provides clinical insights into the phenotypic effects of GDAP1 mutations in CMT patients. The findings highlight the adverse clinical course and severe disability associated with GDAP1 mutations, including weak limb and laryngeal muscles. ConclusionPatients with GDAP1 mutations and autosomal recessive neuropathy present with dysphonia and require interventions such as surgery, braces, physical therapy, and exercise. Early diagnosis and comprehensive clinical evaluations are crucial for managing CMT patients with GDAP1 mutations.

Facial nerve neurographies in intensive care unit-acquired weakness

BackgroundPatients with an intensive care unit-acquired weakness (ICU-AW) often present clinically with severe paresis of the limb and trunk muscles while facial muscles appear less affected. To investigate whether the facial nerves are partially spared from this condition, we performed both peripheral and cranial nerve conduction studies in critically ill patients.MethodsIn patients requiring prolonged ICU therapy, the motor and sensory nerve conduction velocities of the peroneal, ulnar and facial nerves and the muscle action potentials of the associated muscles, as well as the orbicularis oculi reflexes were assessed shortly after admission, and on ICU days 7 and 14.ResultsEighteen patients were included in the final data analysis (average age 54.2 ± 16.8 years, 8 females). The amplitudes of the peroneal nerve compound muscle action potentials (CMAPs) were reduced in all patients at ICU days 7 and 14 (F(1.39; 23.63) = 13.85; p < 0.001). There was no similar decrease in the CMAP amplitudes of the ulnar or facial nerve. Other parameters of nerve function (latencies, sensory and motor nerve conduction velocities, sensory nerve action potentials) remained unchanged. The reproducibility of the orbicularis oculi reflex was reduced during the disease course, while its latencies did not change significantly during the disease course.ConclusionsThere is a relative preservation of CMAPs in facial and hand as opposed to foot muscles. This is compatible with the clinical observation that the facial muscles in patients with ICU-AW are less severely affected. This may be primarily a function of the nerve length, and consequently more robust trophic factors in shorter nerves.Trial registration This study was prospectively registered in the German Clinical Trial Register on April 20th 2020 (DRKS00021467).

Polineuropatía asociada a infección por VIH. Revisión del tema y presentación de un caso

La infección por el virus de inmunodeficiencia humana (VIH) constituye un problema de salud pública. La afectación neurológica en los pacientes infectados por el VIH es frecuente, involucrando tanto al sistema nervioso central como al periférico, y en algunos casos puede ser la primera manifestación de la infección. Entre las afecciones neurológicas, las neuropatías periféricas pueden observarse en el 100% de las autopsias. Las mismas pueden adoptar diferentes formas, que por lo general dependen de la fase de la enfermedad en la que se encuentre el paciente. Las neuropatías autoinmunes como el síndrome de Guillain-Barré y la polineuropatía desmielinizante inflamatoria crónica (CIDP) aparecen en los estadios iniciales de la infección, cuando el conteo de CD4 está ligeramente disminuido. La CIDP tiene criterios clínicos y electrofisiológicos bien definidos que la diferencian de otras formas de neuropatías periféricas, responde bien al tratamiento inmunomodulador, pero su diagnóstico puede ser difícil de realizar debido a su forma insidiosa de comienzo. Se realiza una breve revisión de las neuropatías periféricas que pueden asociarse a la infección por VIH y se presenta un caso de asociación de esta infección con CIDP.

Brain imaging findings of methanol poisoning and detection of chronic stage nervous system damage: A case report

In this article, we presented the chronic neurological findings of an acute case of methanol intoxication due to the use of homemade alcohol. In the neurological examination performed 6 months after intoxication, bilateral vision loss, tremor, dysarthria, dysphagia, loss of taste sensation, and decrease in the Cognitive State Test score were detected. Peripheral polyneuropathy consistent with axonopathy was detected in the peripheral nerve conduction study, and optical neuropathy was detected in the examination of the pattern visual evoked potential. Brain magnetic resonance imaging revealed findings compatible with bilateral putaminal necrosis.

Myoclonus and tremor in chronic inflammatory demyelinating polyneuropathy: a multichannel electromyography analysis.

Information regarding involuntary movements in chronic inflammatory polyneuropathy (CIDP) is gradually increasing. Our goal is to identify the types of involuntary movements in CIDP. All patients who were followed with the diagnosis of CIDP were invited for clinical and electrophysiological evaluations. Demographic and clinical findings (age, gender, duration of illness, diagnosis, treatments) were noted. Clinical examination and multichannel surface electromyography were done. We also performed routine upper and lower extremity peripheral nerve conduction studies, F-waves, long latency reflexes, blink reflex, mixed nerve silent period and cutaneous silent period in all patients. Twenty-two patients accepted the invitation. Eleven patients with CIDP had involuntary movements. Ten (45.5%) patients with CIDP had tremor and seven (31.8%) had short-duration and high-amplitude myoclonus. Regarding demographic, clinical and electrophysiological features, there was no significant difference between patients with and without tremor. The latencies of R1, R2 and R2c components of BR were longer among CIDP patients without tremor compared to CIDP patients with tremor. Presence of myoclonus (p = 0.007) and delayed F-waves (p = 0.008) were associated with the presence of tremor. Tremor and myoclonus were frequent in CIDP. The fact that myoclonus was detected in the majority of patients only by multichannel surface EMG who were clinically evaluated as pure tremor suggests that a more detailed electrophysiological evaluation is required. There was no difference in the medications used or other clinical features between patients with and without tremor.

Sympathetic skin responses and electromyographic reaction times in chronic autoimmune thyroiditis: An overlooked electrodiagnostic study.

Objectives This study aims to evaluate peripheral nerve functions, sympathetic skin responses (SSRs), and electromyographic (EMG) reaction times in hypothyroid patients and to compare them to healthy individuals. Patients and methods Between January 2007 and September 2007, a total of 54 patients with Hashimoto’s thyroiditis including 35 euthyroid (3 males, 32 females; mean age: 45.2±10.2 years; range, 35 to 60 years) and 19 with subclinical hypothyroidism (2 males, 17 females; mean age: 43.2±12.6 years; range, 40 to 65 years) were included in the study. The control group consisted of 35 healthy individuals (5 males, 30 females; mean age: 39.1±9.3 years; range, 29 to 52 years). Nerve conduction studies (NCSs), SSRs of the hand and foot obtained by stimulation of the contralateral median nerve, and EMG reaction times of the extensor indicis proprius muscle were performed in all subjects. Results There was no significant difference in peripheral NCSs and SSRs between patients and the control group. However, reaction times were longer in the AIT patients compared to the healthy individuals suggesting alterations in cognitive function related to the primary disease process in AIT. Conclusion Electrodiagnosis of autonomic nervous system involvement and cognitive impairment can be challenging in AIT. However, EMG reaction times and SSRs are practical and useful tools that are often overlooked. On the other hand, SSRs may be combined with more quantitative tests, such as sudomotor axon reflex testing, to allow us to better determine the extent of involvement of the autonomic nervous system in AIT.

Relapsing inflammatory neuropathy with normal peripheral nerve conduction studies – a paradoxical phenomenon in two patients

The diagnosis of Guillain Barre Syndrome and Chronic Inflammatory Demyelinating Polyneuropathy depends on an appropriate history, examination, CSF cyto-protein dissociation and abnormal peripheral nerve conduction studies (PNCS). We present two cases suggestive of GBS but with repeatedly normal PNCS, a paradoxical phenomenon.

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.

Differentiating Moebius syndrome and other congenital facial weakness disorders with electrodiagnostic studies.

Congenital facial weakness (CFW) can result from facial nerve paresis with or without other cranial nerve and systemic involvement, or generalized neuropathic and myopathic disorders. Moebius syndrome is one type of CFW. In this study we explored the utility of electrodiagnostic studies (EDx) in the evaluation of individuals with CFW. Forty-three subjects enrolled prospectively into a dedicated clinical protocol and had EDx evaluations, including blink reflex and facial and peripheral nerve conduction studies, with optional needle electromyography. MBS and hereditary congenital facial paresis (HCFP) subjects had low-amplitude cranial nerve 7 responses without other neuropathic or myopathic findings. Carriers of specific pathogenic variants in TUBB3 had, in addition, a generalized sensorimotor axonal polyneuropathy with demyelinating features. Myopathic findings were detected in individuals with Carey-Fineman-Ziter syndrome, myotonic dystrophy, other undefined myopathies, or CFW with arthrogryposis, ophthalmoplegia, and other system involvement. EDx in CFW subjects can assist in characterizing the underlying pathogenesis, as well as guide diagnosis and genetic counseling.

Peripheral nerve conduction study in early cognitive impairment of Alzheimer's disease

AbstractBackgroundMild cognitive impairment (MCI) individuals are at a higher risk to develop dementia, especially due to Alzheimer’s disease (AD). Dyskinesia, such as facial expressions, gait and postural changes, retardation and tremor, occurs even before significant clinical symptoms of AD. Besides, elders with central nervous degenerative diseases are more likely to have peripheral neuropathy. However, few studies have been devoted to exploring the relationship between peripheral nerve function and early cognitive impairment. The aim of this study was to compare MCI individuals with the normal population for peripheral nerve conduction, and to assess its relationship with cognitive function in elderly population living in Shanghai.Method74 MCI and 82 healthy controls (HC) underwent a peripheral nerve conduction examination and a neuropsychological evaluation. In order to minimized the effect of somatic diseases on peripheral nerve function, all the participants had no diabetes, thyroid dysfunction, Parkinson's disease and peripheral neuropathy. Nicolet EDX was used to assess peripheral nerve conduction of upper and lower limb, including median and sural sensory and median and peroneal motor nerve action potential amplitudes and velocities. Then we compared the peripheral nerve conduction results between two different cognitive groups. Furthermore, we also investigated the relationship between the peripheral nerve conduction and cognitive function.ResultBetween the two groups, MCI was older than HC (70.36±7.38 vs 68.04±6.27, p=0.07) although there was no significant difference. MCI group had less years of education (10.05±3.58 vs 11.45±2.57, p=0.009) and more depressive symptoms (3.65±4.37 vs 2.70±4.17, p=0.044), but no difference was found in gender. Median and peroneal motor nerve velocities were found slower in MCI group compared to HC group (54.51±4.18 vs 47.13±5.90, p=0.011; 56.36±4.72 vs 49.29±5.65, p=0.023). Both median (p=0.005) and peroneal (p=0.003) motor nerve velocities were correlated with MoCA. Furthermore, linear regression revealed that, after taking age, gender, education, depression and body mass index (BMI) into account as covariates, median motor nerve velocity was associated with MoCA (p=0.019).ConclusionOur study found that peripheral motor nerve velocity may be correlated with early cognitive impairment of AD, suggesting a new, possible research direction of early identification markers for AD.

Efficacy of homoeopathic treatment for diabetic distal symmetric polyneuropathy: A multicentric randomised double-blind placebo-controlled clinical trial.

BackgroundIn course of diabetes, some 20–90% of individuals eventually develop diabetic neuropathy. Looking at the disease burden research studies in Homoeopathy were conducted and have shown positive results. These studies were not robust enough to prove the efficacy of individualized homoeopathy. ObjectiveTo assess efficacy of individualized homoeopathic medicines in management of DDSP. MethodsA multi-centric double-blind, placebo controlled, randomised clinical trial was conducted by the Central Council for Research in Homoeopathy at six centres with a sample size of 84. Based on earlier observational studies and repertorial anamnesis of DDSP symptoms 15 homoeopathic medicines were shortlisted and validated scales were used for evaluating the outcomes post-intervention. Primary outcome measure was change in Neuropathy Total Symptom Score-6 (NTSS-6) from baseline to 12 months. Secondary outcomes included changes in peripheral nerve conduction study (NCS), World Health Organization Quality of Life BREF (WHOQOL-BREF) and Diabetic Neuropathy Examination (DNE) Score at 12 months. ResultsData of 68 enrolled cases was considered for data analysis. Statistically significant difference (p<0.014) was found in NTSS-6 post intervention in the Verum group. Positive trend was noted for Verum group as per the graph plotted for DNE score and assessment done for NCS. No significant difference was found between the groups for WHOQOL-Bref. Out of 15 pre-identified homoeopathic medicines 11 medicines were prescribed in potencies in ascending order from 6C to 1M. ConclusionFurther studies must be taken up with larger sample size and defined parameters for NCS to assess the effectiveness of homoeopathy.

Effects of modified-release fampridine on upper limb impairment in patients with Multiple Sclerosis

BackgroundModified-release 4-aminopyridine (fampridine-MR) is used in the symptomatic treatment of walking disability in patients with multiple sclerosis (MS). Its potential for use in other MS symptoms remains unproven and its mode of action in this context is uncertain. Interest is growing in the use of upper limb outcome measures in clinical trials in patients with Multiple Sclerosis, particularly in advanced or progressive disease. This study tests the following hypotheses: (1) Fampridine-MR improves upper limb function in patients with MS and upper limb impairment. (2) Treatment with fampridine-MR is associated with measurable alterations in objective electrophysiological parameters (evoked potentials and transcranial magnetic stimulation (TMS)) which may predict response to drug treatment. MethodsStudy population: patients with MS of any disease subtype, duration and severity who have symptomatic impairment of one or both upper limbs. A healthy control group was included for validation of clinical and electrophysiological measures. Study design: randomised double blind placebo-controlled trial. Treatment details: participants allocated to either fampridine-MR 10 mg bd or placebo of identical appearance for 8 weeks. Primary outcome: performance on 9-hole peg test (9HPT) after 4 weeks. Secondary outcomes: persistence of effect on 9HPT; grip strength; visual acuity and contrast sensitivity; modified fatigue impact scale score; sensory discrimination capacity; visual, somatosensory and motor evoked potentials; resting motor threshold; paired-pulse TMS; peripheral nerve conduction studies. Results40 patients with MS (60% female, median age 52, median disease duration 13.5 years, median EDSS 6.0) were enrolled. Treatment with fampridine-MR was not associated with any change in upper limb function as measured by the clinical primary or secondary outcomes. Treatment with fampridine-MR was also not associated with any difference in electrophysiological measures of upper limb function. This held true after adjustment for hand dominance, disease duration and severity. Four patients withdrew from the trial because of lack of efficacy or side-effects; all were in the placebo arm. Three patients were admitted to hospital during the study period; one with MS exacerbation (placebo group), one with syncope (drug group) and one with UTI (drug group); otherwise there were no serious adverse events. ConclusionTreatment with fampridine-MR was well-tolerated but did not produce clinical benefit in terms of upper limb function, vision or fatigue, nor was there any measurable effect on objective electrophysiological parameters.

Correlation between risk factors for diabetic peripheral neuropathy and nerve conduction study parameters in children with type 1 diabetes mellitus attending Sudan childhood diabetes centre

Diabetic peripheral neuropathy (DPN) is the commonest microvascular complication of diabetes mellitus. Risk factors related to the development of DPN are mainly duration of diabetes, degree of glycaemic control, height of the patient and age at onset of diabetes mellitus. This study aimed to correlate between the risk factors for diabetic peripheral neuropathy (DPN) and lower limbs nerve conduction study (NCS) parameters in children with type 1 diabetes mellitus attending Sudan Childhood Diabetes Centre. This cross-sectional study recruited 50 patients with type 1diabetes, with mean disease duration of 4.9 ± 3.8 years attending Sudan Childhood Diabetes Centre. NCS parameters (latency, amplitude, and conduction velocity) of sural, common peroneal and posterior tibial nerves were measured bilaterally. Using Pearson correlation statistics, the study revealed significant negative correlation between the patient age and the motor velocities of tibial and common peroneal nerves. Furthermore, it proved significant negative correlation between the patient height and velocities of sural, tibial and common peroneal nerves. It also showed significant negative correlation between the age at onset of the disease and the motor velocities of the right tibial and right common peroneal nerves. Moreover, there was significant negative correlation between HbA1c and the motor velocities of both right and left tibial nerves. Duration of the disease did not show any correlation with NCS parameters. The study proved that most of the risk factors for diabetic peripheral neuropathy decrease significantly the conduction velocity especially of the motor lower limbs nerves in type 1 diabetic children.

(Invited) An Electrochemical Perspective on Electrophysiological Measurements

Electrophysiological measurement such as EEG and peripheral nerve conduction studies are commonly used in neurology research and medical diagnoses. Bioelectrochemical structures and reactions at the molecular to micrometer scale propagate charge through space. Electrophysiological measurements made across distances on the scale of centimeters map collective effects of many charge propagation events. In peripheral nerves, charge propagates along nerves in the limbs at ~50 m/s. Voltages measured from the surface of the skin are in the range of 6 to 8 µV for peripheral nerves and as high as 40-60 µV in EEG studies. Charge propagation events that generate measured electrophysiological signals can be viewed with the same electrostatic fundamentals that describe how potentials are established in electrochemical systems. Polarization of a synaptic membrane generates a flux of positive charge and then a charge balancing flux of negative charge as the membrane depolarizes. The flux separates charge that generates a dipole. The dipole propagates down a peripheral nerve as the membrane separates charge sequentially. A sketch of the dipole is based in electrostatics. From an electrostatic perspective, the separation and magnitude of the charges establishes an electrical potential Φ(x,y,z). Consider a single dipole at an instant in time. Evaluation of charge separation yields a map of potential in space as shown in the Figure. The gradient in the electrical potential establishes the electric field. Migration is driven by potential gradients such that the electric field may play a role in dipole propagation. The Figure is an instantaneous snapshot of potential associated with a dipole in space. In electrophysiological measurements, multiple dipoles events yield the measured voltages as nerve impulses that propagate in time along a peripheral nerve tract. A sketch of the correlations between electrophysiological measurements and electrochemical fundamentals is presented. .... Figure 1

Electromyographic study to predict functional outcome of transforaminal epidural steroid injection in lumbosacral radiculopathy

ContextEpidural steriod injections (ESIs) are commonly used for managment of lumbosacral radiculopathy (LSR). Predicting outcomes after ESIs could be another valuable application of needle electromyography (EMG) in these patients.AimThe aim was to determine if EMG study can predict the functional outcome of transforaminal ESIs in patients with LSR.Materials and methodsThe study included 20 patients with clinical diagnosis of LSR. Peripheral nerve conduction study, late responses, somatomsensory evoked potentials, and needle EMG were performed in both lower limbs followed by transforaminal ESI under fluoroscopic guidance. The functional outcome was evaluated using visual analog scale for pain and Oswestry disability index (ODI) that were performed before and after injections.ResultsThere were statistically significant decrease in pain severity (visual analog scale; P=0.022) and in ODI (improvement in functional score; P=0.029) after injection in patients with symptom duration less than 3 months compared with patients with longer duration of symptoms. In patients with negative EMG findings, there was a significantly greater reduction in pain severity (P<0.01) and ODI score (P<0.01) after injection compared with patients with positive findings. Regression analysis showed that negative needle EMG findings were significant predictors of pain reduction (P=0.001) and functional improvement (P=0.002) in patients with LSR after ESI.ConclusionThis study supports the notion that EMG studies can be used for prediction of functional outcome in patients with LSR performing transforaminal ESI.

Peripheral nerve ultrasonography and nerve conduction study in progressive stage of amyotrophic lateral sclerosis

Background: High-resolution ultrasound has been used to evaluate several neuromuscular conditions.

Isolated dysphagia as initial sign of anti-IgLON5 syndrome.

Objective:To report on dysphagia as initial sign in a case of anti-IgLON5 syndrome and provide an overview of the current literature.Methods:The diagnostic workup included cerebral MRI, fiber optic endoscopic evaluation of swallowing (FEES) with the FEES tensilon test, a videofluoroscopic swallowing study, evoked potentials and peripheral nerve conduction studies, polysomnography, lumbar puncture, and screening for neural autoantibodies. A systematic review of all published cases of IgLON5 syndrome is provided.Results:We report a case of anti-IgLON5 syndrome presenting with slowly progressive neurogenic dysphagia. FEES revealed severe neurogenic dysphagia and bilateral palsy of the vocal cords. Autoantibody screening was positive for IgLON5 IgG (+++, 1:1,000) serum levels but no other known neural autoantibody. Polysomnography was highly suggestive of non-REM parasomnia. Symptoms were partially responsive to immunotherapy.Conclusions:Slowly progressive neurogenic dysphagia may occur as initial sign of anti-IgLON5 syndrome highlighting another clinical presentation of this rare disease.

Study of the association between nailfold capillaroscopic changes and serum level of interleukin-17 in rheumatoid: a clue for emerging vaculitis

The aim of this work was to study nailfold capillaroscopic (NC) abnormalities and serum interleukin-17 (IL-17) level among rheumatoid arthritis (RA) patients and to find whether IL-17 is causally involved in the changes in the capillary vascular bed, such as autoimmune prevasculitic changes. The study was conducted on a group of RA Egyptian patients (n=40) who were diagnosed as having RA based on ACR criteria. Those 40 patients were further divided into two groups. Group 1 included RA patients with clinical signs of skin vasculitis and NC changes (n=6). Group 2 included RA patients with no clinical signs of skin vasculitis and no NC changes (n=34). All patients were subjected to demographic data collection, clinical examination, disease activity score 28 calculation, laboratory measurement (including erythrocyte sedimentation rate, C-reactive protein, rheumatoid factor, antinuclear antibody, antineutrophil cytoplasmic antibody, anti-cyclic citrullinated peptide, and IL-17) andNCexamination. Inaddition, group 1 (n=6) was further subjected to electrophysiological evaluation using peripheral nerve conduction studies to determine the effect of vasculitis on the peripheral nerves. IL-17 level and NC changes showed a significant association in RA vasculitis patients. Elevated levels of serum IL-17 and characteristic NC changes raise their importance in the detection of preclinical rheumatoid vasculitis.

Retinal Neurodegeneration Associated With Peripheral Nerve Conduction and Autonomic Nerve Function in Diabetic Patients

In this study, we evaluated the correlation of retinal thickness with peripheral nerve conduction and autonomic nerve function in diabetic patients. Cross-sectional study. Medical records of 160 patients (mean age, 63.61 ± 12.52 years) with diabetes without diabetic retinopathy or mild nonproliferative diabetic retinopathy (NPDR) were reviewed. The mean retinal thickness of the parafoveal area and ganglion cell/inner plexiform layer (GC-IPL) thickness in 6 macular regions were measured using optical coherence tomography. Peripheral nerve conduction studies were conducted on peroneal and posterior tibial motor nerves and the sural sensory nerve. Five cardiovascular autonomic function tests were performed. We classified patients into groups by severity of peripheral neuropathy and autonomic dysfunction and analyzed the correlations with mean retinal thickness. The mean retinal thickness of the parafovea was 315.05 ± 12.70μm and mean macular GC-IPL thickness was 79.89 ± 4.70μm. Macular GC-IPL thickness showed significant correlation with peripheral nerve conduction (no peripheral neuropathy vs definite peripheral neuropathy: 82.0 ± 4.8μm vs 75.2 ± 3.8μm, P < .001). GC-IPL thickness decreased with severity of autonomic nerve dysfunction (no/mild dysfunction vs severe dysfunction: 81.2 ± 6.6μm vs 77.6 ± 5.9μm, P= .005). There was no significant correlation between the retinal thickness of the parafovea and electrodiagnostic tests. The decrease of GC-IPL thickness was positively correlated with both peripheral nerve conduction and autonomic nerve function in diabetic patients who presented with no diabetic retinopathy or mild NPDR.

A Comparative Peripheral Nerve Conduction Study in Type-2 Diabetics with Symptoms of Polyneuropathy with Age and Sex Matched Normal Subjects

Background: Diabetes Mellitus is one among the diseases that affects peripheral nervous system and symptomatic Neuropathy in uncontrolled Diabetes is one of the commonest incapacitating complications. Electro diagnostic tests can be used to detect Diabetic Neuropathy at an early stage (before development of the signs or symptoms of Neuropathy). Nerve Conduction Study (NCS) is considered to be the most sensitive, reliable, non-invasive and objective means of investigations of Diabetic Polyneuropathy. Diabetic Neuropathy is curable, and hence if detected, the proper treatment can be instituted in early stages, which again, can give rise to good outcome. As the peripheral nerve has the ability to regenerate, line of treatment can be planned. Aims & Objectives: To compare and analyze the peripheral nerve conduction studies in symptomatic diabetic neuropathy cases with age and sex matched normal subjects emphasizing on use of Nerve conduction studies as a diagnostic approach to prevent Severe Neuropathy. Methods: The study group consists of 9 cases diagnosed with Diabetic neuropathy referred to our neurophysiology lab and control group consists of 9 age and sex matched normal subjects who are nondiabetic, healthy volunteers. Statistical analysis was done using unpaired t-test and 8 out of 9 cases considered for statistical analysis. Motor and Sensory nerve conduction studies conducted in both Upper (Median and Ulnar nerves) and Lower limbs (Tibial and Peroneal nerves) using bipolar surface electrodes with RMS EMG EP MARK-II machine. Results: There is a definite decrease in amplitude and nerve conduction velocities of both the sensory and motor components, axonal and demyelinating type significantly correlating with higher HBA1c levels. F minimum latencies of Median, Tibial and Peroneal nerves were increased possibly more of demyelinating type of Polyneuropathy. Conclusion: NCS being a simple, harmless, non-invasive and objective technique along with easy interpretation of results can be used routinely to evaluate the status of nerves in patients with Type 2 Diabetes Mellitus to prevent more disabling state at the earliest.