Sural Nerve Conduction Studies Research Articles

Reference values for nerve conduction studies of the peroneal, tibial, and sural nerve derived from a large population-based cohort: Associations with demographic and anthropometric characteristics-The Maastricht study.

Nerve conduction studies (NCSs) are widely used to support the clinical diagnosis of neuromuscular disorders. The aims of this study were to obtain reference values for peroneal, tibial, and sural NCSs and to examine the associations with demographic and anthropometric factors. In 5099 participants (aged 40-79 years) without type 2 diabetes of The Maastricht Study, NCSs of peroneal, tibial, and sural nerves were performed. Values for compound muscle action potential (CMAP) and sensory nerve action potential amplitude, nerve conduction velocity (NCV), and distal latency were acquired. The association of age, sex, body mass index (BMI), and height with NCS values was determined using uni- and multivariate linear regression analyses. Detailed reference values are reported per decade for men and women. Significantly lower NCVs and longer distal latencies were observed in all nerves in older and taller individuals as well as in men. In these groups, amplitudes of the tibial and sural nerves were significantly lower, whereas a lower peroneal nerve CMAP was only significantly associated with age. BMI showed a multidirectional association. After correction for anthropometric factors in the multivariate analysis, the association between sex and NCS values was less straightforward. These values from a population-based dataset could be used as a reference for generating normative values. Our findings show the association of NCS values with anthropometric factors. In clinical practice, these factors can be considered when interpreting NCS values.

Cross-Sectional Study of the Relationship Between Medial Plantar Nerve Conduction Studies and Severity of Diabetic Neuropathy.

Diabetic peripheral neuropathy (DPN), a complication of diabetes, is detected only in later stages. Medial plantar nerve (MPL) can identify earlier stages of neuropathy. We evaluated the correlation of MPL sensory nerve action potentials (SNAPs) and severity of DPN measured using the Toronto Clinical Neuropathy Score (TCNS). In this hospital-based, cross-sectional study, we recruited diabetic subjects referred for suspected DPN. Neuropathy was graded with TCNS. Sural nerve conduction studies were performed using standard techniques. MPL studies were conducted using the modified Ponsford technique. All evaluations were performed on Nihon Kohden (model MEB 9200K). Averaged MPL SNAP was correlated with TCNS using Pearson's correlation coefficient. To estimate a correlation of 0.4 with 80% power (P = 0.05), we needed 46 subjects. Linear regression was conducted to adjust for age, duration, and diabetic control. Receiver operating characteristic (ROC) curve analysis was performed to obtain the cutoff for MPL SNAP values using the Youden index. Fifty-one subjects with a mean age of 53.5 years (8.7) and mean duration of diabetes of 10.2 years (7.2) were included. MPL SNAPs were recordable in 12 patients, and the mean amplitude was 5.15 (2.9) µV. There was correlation between MPL SNAP and TCNS (r = -0.43, P = 0.02). No confounding was seen. Use of MPL SNAP resulted in diagnosis of DPN in an additional six (11.8%) patients. The ROC curve suggested that MPL SNAP cutoff of 1.05 µV had an accuracy of 67% in identifying neuropathy as defined by TCNS. MPL SNAP has a moderate correlation with clinical score and identifies more diabetic neuropathy than sural nerve.

Prevalence of Peripheral Neuropathy (PN) Among Patients with Asymptomatic Monoclonal Gammopathies: A Clinical & Electrophysiological Study

Introduction: Asymptomatic monoclonal gammopathies (MGUS, SMM or aWM) are common among adults >50y. Peripheral neuropathy (PN) refers to any disorder of the peripheral nervous system including mononeuropathies, and symmetrical or asymmetrical polyneuropathy. PN is also common among individuals >50y. Common risk factors include diabetes, vitamin deficiencies, alcohol, renal insufficiency, hypothyroidism, autoimmune diseases and exposure to neurotoxic medication. Epidemiological studies have shown an association between monoclonal gammopathies and PN but a mechanistic link has been established only for some (anti-MAG IgM-related PN, amyloidosis, POEMS syndrome etc). However, the true prevalence of PN among patients (pts) with monoclonal gammopathies is unknown and remains challenging to associate monoclonal gammopathy with PN. The aim of our study is to establish the prevalence of PN in a large cohort of pts with asymptomatic monoclonal gammopathy and identify potential determinants. Methods: This is an ongoing prospective, non-invasive study aiming to screen ~1500 pts with asymptomatic monoclonal gammopathies for PN. Pts under regular follow-up at the Department of Therapeutics, University of Athens, Greece are screened for neuropathic symptoms using the Michigan Neuropathy Screening Instrument (MNSI), a validated screening tool for the presence of PN that consists of 15 yes/no items. A cut off ≥ 4 has been proposed as a screening cut off in diabetic PN. All pts scoring ≥4 on MNSI and pts scoring <4 but without risk factors for PN were assessed clinically and electrophysiologically (EDX) with standard nerve conduction studies (NCS), sympathetic skin response (SSR) test and - if needed - electromyography (EMG) by a specialist. NCS protocol includes assessment of the median nerve (motor and sensory), superficial radial nerve (sensory), tibial nerve (motor) and sural nerve (sensory) conduction studies. Axonal PN was diagnosed when the sural to radial ratio (SRAR) is below 0.25 and/or the sural nerve action potential is below 6μV, demyelinating PN if the EAN/PNS criteria for demyelination are fulfilled and sympathetic dysfunction when the SSR amplitude was <500 uV. Results: As of to date, 320 pts (42.8% males, median 67y) with asymptomatic monoclonal gammopathy have been screened; 64.3% had a diagnosis of MGUS (72.3% IgG, 14.1% IgA, 6.3% IgM, 7.3% light chain only), 23.9% had SMM and 11.8% had aWM. Among enrolled pts, 217 (68%) had no common risk factors for PN and 82 pts (25.6%) had an MNSI score ≥4; the commonest symptoms were cramps (48.4%), weakness (26.9%) and pain when walking (26.3%). Among pts without risk factors for PN, 42 (19.4%) had an MNSI score ≥ 4 and the commonest symptoms were cramps (44.7%), pain when walking (22.1%) and weakness (21.7%) (Table 1). There was no difference in the prevalence of MNSI score ≥4 among pts with different paraprotein types. To date, 105 pts (41.9% males, median 66y) had EDX evaluation, of which 77 (73%) had no common risk factors for PN. Among the EDX evaluated pts, 23 (21.9%) had large fiber PN, 42 (40%) had sudomotor dysfunction and 53 (50.5%) had large fiber PN and/or sudomotor dysfunction. Among the cohort of pts without risk factors for PN, 13 (16.9%) had large fiber PN, 25 (32.5%) had sudomotor dysfunction and 34 (44.2%) had large fiber PN and/or sudomotor dysfunction. Nineteen pts that went through EDX were asymptomatic (MNSI=0), of those 4 (21.1%) had large fiber PN, 4 (21.1%) had sudomotor dysfunction and 7 (33.3%) had large fiber PN and/or sudomotor dysfunction. Only one patient, without other risk factors, had a demyelinating neuropathy while all other pts had a length-dependent axonal sensory or sensorimotor neuropathy. Pts with large fiber PN were older (73.7±11.4 vs 63±9.4, p<0.001) but no significant differences were found regarding sex, or paraprotein or light chain type. Pts with sudomotor dysfunction were more likely to have a non-IgM monoclonal gammopathy (90.2% vs 72.6 %, p=0.029). Conclusion: Peripheral neuropathy is common in pts with monocloncal gammopathies affecting ~20% of those without any other risk factors for PN. Although most pts with PN describe mild symptoms, both large fiber PN and sudomotor dysfunction may remain completely asymptomatic. This data provides a new insight into the prevalence of PN in pts with monoclonal gammopathies with implications for future research. The study is ongoing and updated results will be presented.

Comparison of ulnar, median, and sural sensory nerve conduction studies between demyelinating and axonal forms of Guillain-Barré Syndrome

Background: Guillain-Barré syndrome (GBS) is an important neurological disease that can cause disability. Axonal GBS and acute inflammatory demyelinating polyradiculoneuropathy (AIDP) are two important subgroups.
 Methods: Patients with clinical and electrodiagnostic features compatible with GBS were included in this retrospective study. The patients were divided into two groups neurophysiologically as Axonal GBS and AIDP. Medical research council (MRC) scores of the patients' muscles, median / ulnar / posterior tibial / peroneal / sural nerve conduction study findings were included in the analyses. Sural sparing pattern was considered as the absence of median/ulnar compound nerve action potential (CNAP) and present sural nerve CNAP (SS-M/SS-U).
 Results: Twelve AIDP and 10 Axonal GBS patients were included in the study. MRC scores were not different between the two groups (p=0.895). CNAPs of the right median and ulnar nerves were smaller in AIDP patients than in Axonal GBS patients (p

ANXIETY AND DEPRESSION IN TYPE 2 DIABETES MELLITUS: A STUDY INCLUDING NERVE CONDUCTION STUDY AND NEUROPATHIC PAIN

Objective: It is known that neuropathy, neuropathic pain and psychiatric disorders are associated with diabetes mellitus (DM). It was aimed to find out whether there is a relationship between nerve conduction study findings, neuropathic pain, depression and anxiety.
 
 Material and Methods: Type 2 DM patients that applied to our clinical neurophysiology laboratory between September 2021 and January 2022 were included in this study. Median, ulnar, sural, peroneal and posterior tibial nerve conduction studies were performed on the patients. Douleur Neuropathique 4 Questions (DN4) was applied to the patients to evaluate neuropathic pain. Hospital Anxiety and Depression Scale (HADS) was applied to the patients. Anxiety (HADS-A) and depression (HADS-S) scores, which are the two subsections of HADS, were included in the analysis.
 
 Results: Forty DM patients (27 males, 13 females) were included in the study. The mean age of the patients was 57.9±12.7 (min-max 23-83) years. The number of patients with neuropathic pain, polyneuropathy according to neurophysiological findings, abnormal HADS-A and HADS-D scores were 32 (80%), 23 (58%), 17 (43%), and 24 (60%), respectively. Neuropathic pain was present in 22 (96%) and 10 (59%) of the patients with and without polyneuropathy, respectively. Neuropathic pain was found in 22 (92%) patients with depression and 16 (63%) patients without depression (p=0.046). Among patients with neuropathic pain, compound nerve action potential amplitudes of median, ulnar and sural nerves were lower than those without neuropathic pain (p=0.011, p=0.027, p

Comparing Screening Tools and Electrophysiological Findings of Sural and Peroneal Nerves in the Diagnosis of Neuropathy in Patients with Diabetes: A Cross-sectional Study

Background: Some clinical scoring systems as the quantitative tools have been developed to assess the presence and severity of Diabetic Peripheral Neuropathy (DPN) based on both the patient’s complaints and the physicians’ findings. This study was aimed at assessing the presence and severity of sural and peroneal nerve neuropathies using Michigan Neuropathy Screening Instrument (MNSI) and United Kingdom Screening Test (UKST) questionnaire compared with electrodiagnosis assessments. Methods: 148 patients with Diabetes Mellitus (DM) including 80 females and 68 males with a mean age of 57.6, 19 type 1DM and 129 type 2 DM were recruited in this study. The findings of the electrophysiological study such as peroneal and sural nerves’ conduction delay, velocity and amplitude were gathered. The patients were also assessed regarding the clinical neuropathy status using the two instruments of MNSI and UK. Results: The mean neuropathy score of MNSI and UKST were 2.2 (1.7) and 4.1 (3.0), respectively. Each instrument detected the DPN in 47.3% and 64.9% of the patients, respectively. Also, based on the nerve conduction studies (NCS), the neuropathy of sural and peroneal nerves was found in 54.1% and 79.7%, respectively. Unlike the peroneal nerve, there was a significant agreement between the electrodiagnosis assessment and the screening tools in the diagnosis of sural nerve neuropathy. Conclusion: Given that NCS is a practical, simple, and non-invasive approach and also can determine the level of damage and regeneration in peripheral nerves, sural nerve conduction study is suggested as a convenient option for screening and diagnosing the diabetic neuropathy.

Sural nerve conduction study: Reference values in the Algerian population

Objectives: The sural nerve is the most tested sensory nerve in the lower extremities in the electrodiagnostic assessment of peripheral neuropathies. This study presents the reference values of the sural nerve conduction study (NCS) from a significant sample of the Algerian population. Methods: This is a prospective study of right sural NCS in healthy subjects based on the later recommendations of AANEM-NDTF. The nature of the distribution of each electrophysiological parameter was therefore determined. The lower and upper limits were calculated by using the 5th and 95th percentiles respectively and a logarithmic transformation was performed for Sensory Nerve Action Potential (SNAP) amplitude distribution. Results: 115 subjects aged between 20 and 60 years were selected, including 58 women and 57 men. Unlike Sensory Nerve Conduction Velocity (SNCV), the distribution of SNAP amplitude is not Gaussian. The lower limit of SNAP amplitude was 7.70 µV when using the 5th percentile and 6.80 µV by using the Standard Deviation (SD) method after log transformation. Similarly, the lower limit of SNCV was 43 m/s. The SNAP amplitude was greater in women and decreased with age, height and BMI. Conclusion: The values found in this study are comparable to those published in the literature. It may be more appropriate to determine the reference values using percentiles as recently recommended by several authors.

Clinical Predictors And Levels Of Physical Activity Among Cancer Survivors Treated With Neurotoxic Chemotherapy

PURPOSE: Chemotherapy-induced peripheral neuropathy (CIPN) is a common side-effect for cancer survivors and may negatively impact on physical activity (PA). The primary aim of our study was to descriptively quantify PA levels among cancer survivors treated with neurotoxic chemotherapy regimens. Our secondary aims: 1) investigated the proportion of survivors with CIPN symptoms interfering with PA participation, and 2) investigated CIPN-related predictors of walking and moderate-vigorous PA. METHODS: 361 participants were assessed cross-sectionally post-neurotoxic chemotherapy (68% female, median (IQR) age 59.5 (50-68) years, 12 (6-24) months post-treatment completion). PA was self-reported (IPAQ) and classified as meeting recommended moderate-vigorous PA guidelines (≥150 minutes/week) or not. CIPN severity (NCI-CTCAE, FACT/GOG-Ntx13), sural and tibial nerve conduction studies, and balance (Swaymeter) were assessed. RESULTS: 47% of participants did not meet recommended PA guidelines. 25% did not participate in any moderate-vigorous PA. 71% presented with CIPN symptoms (≥grade 1 NCI). 25% reported that their CIPN symptoms interfered with PA, who had impaired balance (p = .02), but not reduced sural (p = .10) or tibial nerve (p = .17) nerve amplitudes. Univariate analyses identified that survivors aged ≥60, with grade ≥ 1 NCI CIPN, diagnosed with stage III/IV disease or were obese were less likely to meet PA guidelines (all p < .05), although regression models identified older age, higher BMI and female sex were associated with lower levels of walking and moderate-vigorous PA. CONCLUSIONS: Many cancer survivors exposed to neurotoxic chemotherapy have low PA levels. Female cancer survivors, who are older, and with higher BMIs are less likely to participate in walking and moderate-vigorous PA post-neurotoxic chemotherapy. Tailored interventions are needed to increase PA in this population to improve physical function and quality of life.

Physical activity behaviors in cancer survivors treated with neurotoxic chemotherapy.

There are many barriers to physical activity among cancer survivors. Survivors treated with neurotoxic chemotherapy may develop chemotherapy-induced peripheral neuropathy (CIPN) and experience additional barriers related to sensorimotor and mobility deficits. This study examined physical activity behaviors, including physical activity predictors, among cancer survivors treated with neurotoxic chemotherapies. A cross-sectional study of 252 participants, 3-24months after neurotoxic chemotherapy, was undertaken. Physical activity was self-reported (IPAQ). CIPN was self-reported (FACT/GOG-Ntx-13), clinically graded (NCI-CTCAE), and objectively measured using neurological grading scales and neurophysiological techniques (tibial and sural nerve conduction studies). Balance (Swaymeter) and fine motor skills (grooved pegboard) were assessed. Regression models were used to identify clinical, demographic and CIPN predictors of walking and moderate-vigorous physical activity. Forty-four percent of participants did not meet recommended physical activity guidelines (≥150min/week). Sixty-six percent presented with CIPN. Nineteen percent of participants with CIPN reported that symptoms interfered with their ability to be physically active. A lower proportion of survivors aged ≥60, with grade ≥1 CIPN or BMI ≥30, reported meeting physical activity guidelines (all p<.05). Regression models identified older age, higher BMI, and patient-reported CIPN associated with lower walking, while higher BMI and females were associated with lower moderate-vigorous physical activity. Neurologically assessed CIPN did not associate with walking or moderate-vigorous physical activity. Cancer survivors exposed to neurotoxic chemotherapy have low physical activity levels. Further work should examine the factors causing physical activity limitations in this cohort and designing interventions to improve physical function and quality of life in survivors.

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...

Foot Deformity in Patients With Ankylosing Spondylitis: Is It Associated With Functionality and Disease Activity?

Foot involvement affects mobility and functionality in patients with ankylosing spondylitis but it remains unknown if foot deformities in ankylosing spondylitis patients affect functionality, disease activity, and quality of life. The aim of this study was to evaluate in detail the presence of a relationship between radiologically detected foot deformities in ankylosing spondylitis patients and both clinical and electrophysiological findings. The cross-sectional study included 110 patients with ankylosing spondylitis who were diagnosed according to the Assessment in Spondyloarthritis International Society criteria and were followed in our hospital. Demographic and clinical data of all patients were recorded. Bilateral lateral foot x-rays and electrophysiology examinations were evaluated in all subjects. The arch in the dominant foot of the patients was classified in 3 groups as pes cavus, pes planus, or normal. The clinical outcomes, physical examination and electrophysiological findings were compared between the groups, and correlations were examined of the foot deformities with these parameters. Foot deformities were determined at a high rate (74.5%). These deformities affected foot pain, disability and quality of life. Pes cavus deformity was found to be associated with hip pain and enthesopathy. In the electrophysiological studies, the presence of pes planus was found to be associated with the findings of the tibial and sural nerve conduction studies, and the presence of pes cavus with the findings of the peroneal nerve conduction study. In conclusion, foot deformities may have an effect on the quality of life and functionality in ankylosing spondylitis patients.

Erratum: Sural and medial plantar nerve conduction study in the diagnosis of subclinical diabetic neuropathy

Erratum: Sural and medial plantar nerve conduction study in the diagnosis of subclinical diabetic neuropathy

Sural and medial plantar nerve conduction study in the diagnosis of subclinical diabetic neuropathy

Background and Aim Diabetic peripheral neuropathy is one of the most challenging complications of diabetes mellitus. A large number of patients have subclinical neuropathy at the time of detection of diabetes. Proper detection of subclinical diabetic neuropathy is important to prevent more complications. When the symptoms start, there are not many effective therapeutic treatments. Nerve conduction studies (NCS) are known to be sensitive, reliable, noninvasive, and easy to perform to study diabetic neuropathy. Study of the medial plantar and sural nerves can test the most distal parts of the nerves and can be considered an alternative method for the diagnosis of polyneuropathy in the early stages. The aim of this work is to study the utility of both medial plantar and sural nerve conduction in the early diagnosis of diabetic polyneuropathy. Patients and methods Twenty diabetic asymptomatic patients and 20 healthy volunteers of both sexes were included. Their ages ranged between 26 and 44 years and 24 and 46 years, respectively. NCS of the medial plantar and sural nerves for all the patients and control groups is performed using the antidromic method of stimulation for sural nerve and orthodromic stimulation for the medial plantar nerve. Results There were significant changes in the sensory study of both medial plantar and sural nerves of neurologically asymptomatic diabetic patients compared with the control. Conclusion NCS of both medial plantar and sural nerves aids in the detection of subclinical diabetic polyneuropathy.

The Specificity of Near Nerve Method on Sural Nerve Conduction Studies

The Specificity of Near Nerve Method on Sural Nerve Conduction Studies

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

Diabetes mellitus is amongst the most common causes of polyneuropathy worldwide that can eventually terminate to irreversible complications. The remarkable impact of diabetic polyneuropathy as a debilitating condition on the healthcare system and total costs of diabetes care is undeniable. Despite the existence of numerous diagnostic tools such as routine electrophysiologic procedures, its early detection is challenging. This study designed to compare more distal techniques of electrodiagnostic testing, including interdigital sensory nerve conduction studies (NCSs), with conventional approaches and to investigate its role in confirming the early stages of polyneuropathy. This cross-sectional study was performed in the Physical Medicine and Rehabilitation Department of Hazrat Fatemeh Reconstruction Surgery Hospital. Thirty one symptomatic diabetic outpatients and 23 asymptomatic nondiabetic subjects included in our study. We performed nerve conduction studies on five sensory nerves consist of the dorsal sural nerve, medial plantar nerve, digital branches of the interdigital nerves to toes I, II, and III (as a new antidromic technique). In this study, all techniques applied with a surface stimulator and pick-up electrodes. In the group of patients, 9 (29%) and 22 (71%) subjects had impaired and normal routine NCSs, respectively. Interestingly, the results of interdigital nerve studies were abnormal in the 17 out of 22 patients with normal routine NCSs. Also, 11 and 13 subjects had impaired medial plantar nerve and dorsal sural nerve conduction studies, respectively. Accordingly, with this new method, the prevalence of detectable diabetic neuropathy increased from 46% to 83%. We conducted this study intending to demonstrate the application of a new technique for early diagnosis of diabetic polyneuropathy, especially in the presymptomatic and subclinical neuropathies. The digital sensory branches of IDNs known as the most distal sensory nerves, which can be easily evaluated with new antidromic SNAP technique. Our method is simple, non-invasive, suitable, sensitive, and reproducible. There is no need to needle electrode or averaging technique to record an appropriate amplitude of IDN. Thus, it is recommended as a convenient electrophysiological option for early diagnosis of DPN.

Normative reference values for the dorsal sural nerve derived from a large multicenter cohort

ObjectivesDorsal sural nerve conduction studies (NCS) may increase the sensitivity for the diagnosis of polyneuropathy, but clinical use is limited by a lack of reliable normative reference values in all age-groups. The aim of our study was to develop reference values for the dorsal sural nerve, based on a large multicenter cohort of healthy subjects. MethodsBilateral antidromic NCS were performed using standard surface electrodes in 229 healthy subjects (aged 21–80 years; median: 54 years). We assessed the normality of data distribution for amplitudes and conduction velocity (CV) and for their logarithmic (ln) transformation. The effects of age and height were determined using linear regression analysis. ResultsSensory potentials were present in all subjects. Logarithmically transformed data were normally distributed. Age2 and height were most significantly associated with amplitude, and age and height with CV, respectively. There was no significant side-difference. Mean amplitudes (right and left) were 4.8 and 4.9 μV and mean CV 46.7 and 46.9 m/s. Reference limits were e (3.712515 – 0.0000956 * age2 – 0.0115883 * height ± 1.96 * 0.51137) for amplitude and e (4.354374 – 0.0021081 * age – 0.0023354 * height ± 1.96 * 0.11161) for CV. ConclusionsDorsal sural nerve NCS are robust and have well defined normative limits. SignificanceThe findings provide a basis for more sensitive NCS in clinical practice and future studies of the diagnostic accuracy of NCS in polyneuropathy.

Asymptomatic Median Neuropathy in Patients with Diabetic Polyneuropathy

Aim: This study aims to investigate whether asymptomatic median neuropathy (AMN) in patients with diabetic peripheral polyneuropathy (DPNP) is a result of polyneuropathic involvement of median nerve (MN) or its true entrapment. Subjects and Methods: We determined the grades of the Michigan severity scale and the rates of peripheral nerve conduction abnormalities in study subgroups, including patients with carpal tunnel syndrome (CTS), AMN, and normal MN conductions to highlight if the severity of polyneuropathic involvement was different between them. In addition, the results of conventional and comparative nerve conduction studies (NCSs) were compared between these study subgroups. Results: Distributions of Michigan grades and rates of abnormalities in peroneal and sural NCSs were similar between the subgroups (P &gt; 0.05 for all analyses). Abnormality rates of ulnar NCSs were higher in the AMN group than in the other groups, whereas those of comparative transcarpal NCSs were higher in the CTS group. The mean distal sensory latency (DSL) and motor latency (DML) of MN were longer, sensory conduction velocity (SCV) was slower in the CTS group than AMN group, whereas MN motor conduction velocity (MCV) was slower, UN DSL was longer, SCV was slower, SNAP amplitude was smaller, DML was longer, and MCV were slower in the AMN group (P &lt; 0.05 for all analyses). Discussion: Our findings reveal that grade of polyneuropathic involvement is more prominent in AMN, whereas transcarpal MN conduction delay is greater in CTS. The results of the study suggest that the prominence of polyneuropathic impairment in addition to a lesser degree of MN sheet compression obscures the clinical signs in patients with diabetes with AMN.

A Comparison of Neuropathy Quality of Life Tools: Norfolk QOL-DN, PN-QOL-97, and NeuroQOL-28

Aims To explore the effectiveness of the Norfolk QOL-DN (QOL-DN), PN-QOL-97, and NeuroQOL-28 as tools for early detection of diabetic peripheral neuropathy in overweight, obese, and inactive (OOI), prediabetes (PD), and type 2 diabetes (T2D) individuals. Methods Thirty-four adults were divided by A1C [(10 OOI, 13 PD, and 11 T2D] and the sural nerves were tested bilaterally via NC-Stat DPN Check, conducting a sural nerve conduction study (NCS). Participants were individually timed, filling out questionnaires (QOL-DN, NeuroQOL-28, and PN-QOL-97) at a self-selected pace. Data were analyzed and compared to NCS findings to determine the best instrument for early neuropathy detection, usability in screening settings, and application for individuals with OOI, PD, and T2D. Results Abnormal NCS results were obtained from 27 individuals, of which 25 were bilateral and symmetrical. Confirmed DSPN criteria were met for 24, and 1 case met criteria for subclinical neuropathy. Normal NCS findings, reported symptoms, and reduced bilateral sensation were found in 7 cases. The QOL-DN and NeuroQOL-28 significantly predict neuropathy criteria in OOI, PD, and T2D subjects. Analyses revealed the QOL-DN as the quickest for completion (M=5.17; SD=1.83), followed by the NeuroQOL-28 (M=5.58; SD=3.56), and the PN-QOL-97 (M=13.23; SD=3.606). Conclusions The QOL-DN and NeuroQOL-28 are valid early screening measures for DPN detection. Time completion studies revealed that the QOL-DN and NeuroQOL-28 may be used as excellent short screening measures, completed in approximately 6 minutes or less, with reasonable scoring for both. The NeuroQOL-28 is a better fit for immediate feedback, time constraints, or limited staff. Future investigations should evaluate these tools for detection in DPN-prone individuals and in subclinical populations screenings.

Simplified Diagnosis of Critical Illness Polyneuropathy in Patients with Prolonged Mechanical Ventilation: A Prospective Observational Cohort Study.

Background: Although early identification of critical illness polyneuropathy (CIP) is necessary, the established diagnostic criteria have several limitations in the intensive care unit (ICU) setting. The purpose of this study was to define simplified diagnostic criteria of CIP that best predict clinical outcomes. Methods: This prospective, single-center study included 41 ICU patients with prolonged mechanical ventilation (≥21 days). We applied three different sets of diagnostic criteria (combining the results of the Medical Research Council (MRC) sum score and nerve conduction studies (NCS)) for CIP in order to identify the criteria with the best predictive power for clinical outcomes. Results: The simplified diagnosis of CIP meeting the criteria, i.e., that the MRC sum score < 48 and amplitudes of the tibial and sural nerve < 80% of the lower limit of normal, showed the strongest association with 0 ventilator-free days at day 60 (odds ratio, 6.222; p = 0.029). Conclusions: The diagnostic criteria combining the MRC sum score and the tibial and the sural NCS were identified as the simplified criteria of CIP that best predicted the clinical outcomes. The implementation of these simplified criteria may allow for early identification of CIP in the ICU, thereby contributing to prompt interventions for patients with a poor prognosis.

Chronic prurigo: Infrequent association with abnormal sural nerve conduction study results

To the Editor: Chronic prurigo is a highly pruritic condition with ethnic differences in clinical presentation and associations.1 It adversely affects the quality of life of patients. Neuronal plasticity is one of its consistent features.2 It has been suggested that underlying neuropathy may play a role in a subgroup of patients.3 This study was conducted to observe clinical and neurophysiologic attributes of chronic prurigo. The study included 64 consecutive patients from a western province of India and was conducted during 1.5 years after approval from the institutional review board.