Conduction Studies Research Articles

‘When nature breaks the rules’: Guillain-barré syndrome presenting with descending paralysis

Guillain-Barré Syndrome (GBS) typically presents with ascending paralysis, but we report an atypical case involving descending paralysis in a 36-year-old male. The patient experienced upper limb weakness and respiratory muscle involvement, progressing to respiratory distress. Initial cerebrospinal fluid (CSF) analysis and nerve conduction studies (NCS) were normal, delaying the diagnosis. Treatment with intravenous immunoglobulin (IVIG) led to partial recovery. This case highlights the diagnostic challenges of atypical GBS presentations and the importance of early intervention.

Assessment of small fiber neuropathy and distal sensory neuropathy in female patients with fibromyalgia.

We investigated sudomotor dysfunction, small fiber neuropathy (SFN), and their clinical significance in female fibromyalgia patients. Fibromyalgia patients and healthy controls (HCs) were recruited. Clinical and laboratory data were measured. Electrochemical skin conductance (ESC) values of hands and feet were assessed by SUDOSCAN. Additionally, several other methods were employed, including nerve conduction study (NCS), electromyography (EMG), and questionnaires. Spearman correlation coefficient was calculated to identify factors associated with ESC values of SUDOSCAN. Twenty-two female fibromyalgia patients and 22 female HCs were recruited. The fibromyalgia group had lower EQ5D and higher Toronto Clinical Neuropathy scores than the HC group. Most of the EMG/NCS findings of motor and proximal sensory nerves were comparable between the fibromyalgia and HC groups, whereas sensory nerve action potential amplitudes of distal sensory nerves were significantly lower in the fibromyalgia group. Mean ESC values of hands and feet were significantly lower in the fibromyalgia group than in the HC group (57.6 ± 16.2 vs. 68.8 ± 10.3 μS, p = 0.010 for hands, 64.9 ± 11.5 vs. 72.0 ± 8.2 μS, p = 0.025 for feet, respectively). Moderate to severe SFN was more common in the fibromyalgia group (68.2%) than in the HC group (68.2 vs. 50%, p = 0.019). Fibromyalgia disease duration was significantly correlated with the ESC values of hands/feet, and tricyclic antidepressant (TCA) responders had higher ESC values than non-responders. SFN was commonly detected in fibromyalgia patients who had normal EMG/NCS findings and was more severe in fibromyalgia patients with longer disease duration. SUDOSCAN may predict response to TCA therapy.

Evaluation of Split Hand Syndrome in Early Diagnosis of Amyotrophic Lateral Sclerosis by Nerve Conduction Study as a Diagnostic Tool

Background: Amyotrophic lateral sclerosis (ALS), a degenerative disease of the motor neurons that can present diversly. Needle electromyography (EMG) is the gold standard investigation for the diagnosis of ALS. Split hand syndrome (SHS) demonstrated by nerve conduction study (NCS); a noninvasive tool could be useful in diagnosing ALS. This study aimed to assess SHS by NCS in ALS. Methods: This diagnostic accuracy case-control study included 37 cases of ALS and 37 age and gender-matched controls. Compound muscle action potential (CMAP) and distal motor latency (DML) of median and ulnar nerves and the ratio of median and ulnar CMAP and DML were compared between study groups. The diagnostic validity testing of electrophysiological SHS was also done. Results: The mean age of the ALS and control groups were similar, 39.8±2.7 and 39.3±2.6 years, respectively. Sixteen (43.2%) ALS patients were in 30-59 years age group. Male-female ratio was 5.2. In the ALS group, median-ulnar CMAP ratio was lower and median-ulnar DML ratio was prolonged than the control. The diagnostic efficacy of median-ulnar CMAP ratio and DML ratio were calculated. A median-ulnar CMAP ratio cut-off value ≤1 showed 70% sensitivity, 97% specificity, 96% positive predictive value and 77% negative predictive value. A median-ulnar DML ratio cut-off value ≥1.5 showed 48% sensitivity, 89% specificity, 82% positive predictive value and 65% negative predictive value. Conclusion: NCS demonstrating SHS can be an important tool in the early diagnosis of ALS. J Bangladesh Coll Phys Surg 2024; 42: 350-354

Photoinduced modulation and the effect of CNT loading on field effect transistor characteristics of CNT/ZnO/PVDF composite.

CNT/ZnO/PVDF polymer composite phototransistor is studied for the effect of CNT loading and the photoinduced modulation on its transfer characteristics. XRD study shows that the induced strain in the composite is due to the addition of CNT to the ZnO/PVDF composite. The percentage of β-phase present in PVDF is estimated through Raman spectroscopy and the composite's spectral response is determined by UV-Vis absorbance spectroscopy. From the DC electrical conductivity study it is found that the percolation threshold for the composites is obtained for 0.3 wt% of CNT, and 0.44 wt % of CNT loading makes the composite conductive. On adding 1 wt% of CNT, the electrical conductivity of the ZnO/PVDF composite increases 40 times (~ 0.2 μS/m). The temperature-dependent DC conductivity shows that the conductivity of the composites changes from variable range hopping (VRH) to band conductance upon an increase in CNT loading above the percolation threshold and exhibits a negative temperature coefficient (NTC). Two terminal photoconductivity studies are done to understand the photo enhancement and sensitivity of all the devices. PE hysteresis studies show that the polarization of the composites increases drastically from 0.05 μC/cm2 below the percolation threshold to 10 - 30 μC/cm2 above the percolation threshold of CNT in the composite. To study the effect of interfacial polarization on photoconductivity, the composite is studied in a three-terminal device format using SiO2 as a gate dielectric. A band diagram analysis of the oxide-composite and CNT/ZnO interface is done to understand the mechanism behind the photoinduced field effect on transfer characteristics and the effect of CNT loading. The switching behavior and decay time under UV illumination are studied to understand the effect of CNT loading and photoinduced polarization. The persistent photoconductivity decreases and the charge collection efficiency of the FET increases as the CNT loading increases.

Assessment of median nerve with magnetic resonance neurography in cases with carpal tunnel syndrome and controls

Background: Carpal tunnel syndrome (CTS) is a common peripheral nerve entrapment disorder that is diagnosed using clinical signs and symptoms and confirmed via nerve conduction studies (NCSs). While NCS is a semi-invasive procedure, magnetic resonance imaging (MRI) is a non-invasive diagnostic tool that detects macroscopic nerve abnormalities and evaluates a patient's surgical or medication treatment options. This study assessed magnetic resonance neurography (MRN)’s diagnostic and grading value by comparing it to electrodiagnostic studies in patients with CTS and healthy individuals. Methods: This was a cross-sectional study on 27 wrists with CTS and 27 healthy wrists. After history taking and physical examination, we employed an NCS to confirm and determine the severity of CTS, then MRN and diffusion tensor imaging (DTI) were used to calculate apparent diffusion coefficient (ADC), fractional anisotropy (FA), and cross-sectional area (CSA). Results: 18 patients with CTS (27 median nerves) and 15 healthy controls (27 median nerves) were evaluated. The mean FA in the CTS group was significantly lower (0.38 ± 0.05 vs. 0.45 ± 0.06, P < 0.001).The mean CSA and ADC were higher in patients with CTS but not statistically significant. FA’s diagnostic cut-off was 0.42, with a sensitivity of 70.4% and a specificity of 63%. Conclusion: MRN with DTI can be an effective and non-invasive diagnostic technique for the detection of CTS. The FA measure demonstrated adequate sensitivity and specificity for differentiating patients with CTS from healthy individuals.

Ultralow thermal conductivity in Si–Ge nanograin mixtures: A cost-effective granular material for thermoelectric applications

This paper presents a theoretical study of the thermal conductivity of Si–Ge nanograin mixtures using a multiscale computational methodology based on solving the Boltzmann transport equation for phonons with first-principles techniques. A size-dependent correction factor is developed to account for the spatial dependence of the phonon distribution function on nanograin size, with parameters derived from the phonon properties of infinite Si and Ge crystals. This approach makes it possible to accurately calculate the thermal conductivity within a single nanograin, using force constants obtained from first-principles calculations. Thermal energy transport by phonons across grain boundaries is modeled by accounting for phonon transmission by two-phonon processes, weighting specular, and diffuse transmission for each phonon mode as a function of the root-mean-square roughness of the boundary relative to the phonon wavelength. The boundary thermal conductance model, previously validated against experimental data, is implemented using first-principles techniques. This approach excludes specular transmission for phonon modes with specific symmetries while ensuring conservation of the total number of modes in each symmetry class. The study examines the influence of grain size, nanograin mixture composition, temperature, and boundary asperities on the thermal conductivity of nanograin mixtures.

Chronic Immune Sensory Polyradiculopathy (CISP): A Systematic Review of the Literature

Chronic immune sensory polyradiculopathy (CISP) is a rare inflammatory immune disorder affecting the nervous system, primarily targeting the proximal sensory nerve roots. The condition was first described by Sinreich in 2004. We conducted a systematic review of CISP cases published on PubMed to identify common clinical presentations, along with neurophysiological, radiological, cerebrospinal fluid (CSF), and other findings. Our review included a total of 22 patients from 8 articles. Many patients presented with gait difficulties and sensory ataxia and were found to have normal nerve conduction studies (NCS) and electromyography (EMG) but exhibited characteristic abnormalities in somatosensory evoked potentials (SSEP), elevated CSF protein levels, thickened nerve roots on contrast-enhanced lumbar spine MRIs, and histological changes on nerve root biopsies. Clinical improvement was observed following treatment with steroids and/or intravenous immunoglobulin (IVIG). The study concluded that while CISP is rare, it is an important clinical entity to consider, as accurate diagnosis and appropriate treatment can lead to significant improvements in neurological symptoms and disabilities.

Normative values and factors affecting saphenous nerve responses in a south Asian population: a cross-sectional neurophysiological study at a tertiary care hospital in Pakistan

BackgroundThe saphenous nerve, a sensory branch of the femoral nerve, is not commonly included in routine lower extremity nerve conduction studies due to a high frequency of non-recordable responses in healthy subjects. However, saphenous nerve conduction studies are sometimes utilized for the diagnostic assessment of isolated lumbosacral plexus, femoral, or saphenous mononeuropathies. Our study aims to determine normative saphenous nerve response values in a healthy Pakistani population and to investigate their associations with patient body mass index, age, and gender.MethodsThis cross-sectional descriptive study was undertaken over a 3‑month period (May to July 2021) at a neurophysiology department of a tertiary care center in Pakistan. Healthy subjects underwent neurological examination, anthropometric measurements, and bilateral SN nerve conduction studies, with recording of peak-latency, peak-to-peak amplitude and conduction velocity. Statistical analyses and linear regression were conducted to evaluate associations between nerve conduction study variables and patient characteristics. Statistical analyses were also run to assess patient characteristics affecting recordability of saphenous nerve responses. A p-value < 0.05 was considered statistically significant.ResultsAmong 117 subjects, 79.5% (n = 93) had recordable saphenous nerve responses. Median peak-latency, amplitude, and conduction velocity were 3.2 (3.0-3.3) m/s, 7.7 (5.8–9.9) uV, and 44.0 (42.0–47.0) m/s, respectively. Bilaterally absent responses were observed in 20.5% (n = 24) of subjects. Obese participants had a significantly higher number of absent saphenous responses (p = 0.033). Females had shorter peak-latency (p = 0.006) and higher conduction velocity (p = 0.012).ConclusionsSaphenous nerve responses can be used to assess unilateral femoral and saphenous nerve pathologies, provided they are recordable on the asymptomatic side for comparison. Absent bilateral saphenous nerve responses should be interpreted with caution given their prevalence in healthy individuals. Patient characteristics should be taken into consideration when interpreting recordable and nonrecordable saphenous nerve responses.

Electrophysiological Signal Validation of Regenerative Peripheral Nerve Interface at Nerve Ending: A Preliminary Rat Model Experiment.

As the number of extremity amputations continues to rise, so does the demand for prosthetics. Emphasizing the importance of a nerve interface that effectively amplifies and transmits physiological signals through peripheral nerve surgery is crucial for achieving intuitive control. The regenerative peripheral nerve interface (RPNI) is recognized for its potential to provide this technical support. Through animal experiment, we aimed to confirm the actual occurrence of signal amplification. Rats were divided into three experimental groups: control, common peroneal nerve transection, and RPNI. Nerve surgeries were performed for each group, and electromyography (EMG) and nerve conduction studies (NCS) were conducted at the initial surgery, as well as at 2, 4, and 8 weeks postoperatively. All implemented RPNIs exhibited viability and displayed adequate vascularity with the proper color. Clear differences in latency and amplitude were observed before and after 8 weeks of surgery in all groups (p < 0.05). Notably, the RPNI group demonstrated a significantly increased amplitude compared with the control group after 8 weeks (p = 0.031). Latency increased in all groups 8 weeks after surgery. The RPNI group exhibited relatively clear signs of denervation with abnormal spontaneous activities (ASAs) during EMG. This study is one of few preclinical studies that demonstrate the electrophysiological effects of RPNI and validate the neural signals. It serves as a foundational step for future research in human-machine interaction and nerve interfaces.

Guillain-Barré syndrome with overlap between the finger drop variant and acute bulbar palsy: a case report

BackgroundGuillain-Barré syndrome (GBS) is a clinically heterogenous disease and encompasses several distinct clinical variants. Overlap between these variants can pose a diagnostic challenge. We report a case of finger drop variant and acute bulbar palsy overlap as an unusual manifestation of GBS.Case presentationAn 81-year-old man presented with dysarthria, dysphagia, and upper limb weakness. Neurological examination revealed impaired tongue protrusion, the finger drop sign, and diminished brachioradial and triceps muscle reflexes. Nerve conduction studies showed reduced amplitudes and decreased velocities in the median and ulnar nerves. Cerebrospinal fluid analysis revealed albuminocytological dissociation and an anti-ganglioside antibody study revealed positivity for GM1, asialo-GM1, GT1a, GD1b, and GQ1b. As GBS was suspected, we initiated intravenous immunoglobulin treatment, resulting in gradual improvement within the next 3 weeks.ConclusionTo the best of our knowledge, this is the first reported case of an overlap between the finger drop variant and acute bulbar palsy in GBS, highlighting the importance of considering GBS when patients present with a combination of atypical symptoms. Anti-ganglioside antibodies can be helpful and add diagnostic value in these complex cases.

A case of X-Linked adrenoleukodystrophy caused by a novel mutation with singular clinical manifestation: unilateral lower limb weakness.

X-linked adrenoleukodystrophy (X-ALD) is caused by mutations in the ABCD1 gene, leading to the accumulation of very long-chain fatty acids (VLCFAs) in plasma and tissues. It primarily affects the central nervous system white matter and the adrenal cortex. Clinical manifestations include myeloneuropathy, leukodystrophy, and adrenal insufficiency. Reliable methods for diagnosis include VLCFAs and genetic testing. We report the case of a 31-year-old male X-ALD patient who mainly presented with unilateral lower limb weakness. Adrenal insufficiency was not observed, and there was no evidence of peripheral nerve involvement in nerve conduction studies. MRI revealed only mild atrophy of thoracic spinal cord without other relevant abnormalities. Ultimately, Next-Generation Sequencing (NGS) and VLCFAs testing confirmed the diagnosis of X-ALD, and the NGS indicated a novel missense mutation.

Is Dorso-Volar Kinesiotape Added to the Home Exercise Program Effective in the Treatment of Carpal Tunnel Syndrome? Randomized Controlled Electrodiagnostic Study

Abstract Objective We aimed to compare the short- and medium-term efficacy of dorso-volar kinesiotape (KT) added to home exercises (HE) with sham-KT and HE alone in the treatment of mild or moderate carpal tunnel syndrome (CTS) in terms of pain, symptom severity, function, gripping strength, and electrophysiological parameters. Materials and Methods A total of 120 patients (99 females, 21 males) were divided into three groups dorso-volar KT and HE (n=40), sham-KT and HE (n=40), and HE (n=40). Pain (The visual analog scale [VAS]), symptom severity (Boston symptom severity scale [SSS]), functional status (Boston functional status scale [FSS]), nerve conduction study (NCS), hand, finger muscle strength were evaluated pretreatment, at the end of treatment (4th week), and in the third month posttreatment. Results There were statistically significant improvements in VAS (p&lt;0.001), Boston SSS (except HE group) (p&lt;0.001), and Boston FSS (p&lt;0.001) in all groups posttreatment compared to pretreatment, and more in the dorso-volar KT group than pretreatment and the posivite improvement continued at a decreasing rate in the third month posttreatment. At the end of treatment the dorso-volar KT group showed statistically significant improvement in Boston SSS (p&lt;0.001, p&lt;0.001) and Boston FSS (p&lt;0.001, p&lt;0.001) compared to the sham-KT and HE groups. Conclusions The combination of dorso-volar KT and HE program makes a more effective and durable contribution to the improvement of CTS symptom severity, pain and functional status, as well as handgrip strength and NCS parameters compared with sham-KT and HE program.

The Role of 70-MHz Ultrahigh-Frequency Ultrasound in the Peripheral Nerve Injury.

High-frequency ultrasound with an 18-MHz probe (18 MHz-HFUS) plays a relevant role in the evaluation of peripheral nerve injury (PNI). Ultrahigh-frequency ultrasound with a 70-MHz probe (70 MHz-UHFUS) offers higher spatial resolution and could allow a better detection of PNI. This study aimed to compare the diagnostic performance of HFUS and UHFUS in PNI detection. In this retrospective study, were selected, between July 2022 and April 2024, 61 patients underwent HFUS, UHFUS, and nerve conduction study (NCS) for clinical suspicion of traumatic forearm PNI. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy of HFUS and UHFUS in PNI detection were calculated and compared. NCS was used as the reference standard. Nonparametric statistical tests were used. A p value of < 0.05 was considered statistically significant. Comparing the diagnostic performance in PNI detection, the 70 MHz-UHFUS showed a sensitivity and diagnostic accuracy significantly higher than 18 MHz-HFUS, respectively, 98.0% versus 82.4% (p = 0.0205) and 95.1% versus 82.0% (p = 0.0468). Otherwise, not significantly difference were in specificity, PPV, and NPV. UHFUS compared to HFUS demonstrated a higher sensitivity and diagnostic accuracy in PNI detection.

Ultrasound as a Complementary Tool to Electrodiagnostics in the Evaluation of Compressive Neuropathy of the Common Fibular Nerve

Background: Compressive neuropathy of the common fibular nerve (CFN) is increasingly recognized as an etiology for foot drop and falls. Electrodiagnostic (EDX) studies are widely used to evaluate this condition, but such tests are invasive and costly. As with carpal and cubital tunnel syndromes, there may be patients with characteristic symptoms of CFN compressive neuropathy but normal EDX studies in which ultrasound may aid in decision-making. Purpose: We sought to examine the association between ultrasound and nerve conduction studies (NCS) and electromyography (EMG) in the diagnosis of compressive neuropathy of the CFN. Methods: We performed a retrospective review identifying 104 patients who underwent CFN decompression from January 1, 2015, to June 30, 2023. Patients were included if they had both ultrasound and NCS/EMG prior to CFN decompression for compressive neuropathy and if they were older than 18 years at time of surgery. Patients were excluded if they had entrapment secondary to trauma, iatrogenic injury, or if they had had superficial fibular decompression alone without CFN decompression. After applying exclusion criteria, 17 patients remained in the cohort. Results: Mean ultrasound cross-sectional area and side-to-side (STS) ratios were significantly higher in those with abnormal compound muscle action potential (CMAP) amplitudes versus those with normal CMAP amplitudes. The probability of having an abnormal CMAP amplitude when STS ratio was abnormal was 18 times greater compared with those with normal STS ratio. With each unit increase in STS ratio, CMAP amplitude was reduced by 2.79 mV. Conclusions: This retrospective review found that ultrasound may provide complementary diagnostic information to EMG/NCS for compressive neuropathy of the CFN. Further study is needed to examine the relationship between ultrasound findings for CFN compressive neuropathy and results of surgical decompression.

Numerical search for the effective thermal conductivity of cracked media

Spacecraft parts accumulate damage during operation and defects that are invariably present even in new designs may grow. This leads to changes in the behavior of individual parts of the space vehicle and, consequently, to the risk of fracture. A more accurate assessment of spacecraft safety requires internal defects to be included in the material models under consideration. One of the main hazardous effects on space objects is multiple temperature heating and cooling due to periodic action of solar rays. This paper presents a study of thermal conduction of media containing cracks. It is carried out with the help of a technique developed by the authors to determine the effective thermal conductivity of materials and based on approximate numerical solution of the steady-state thermal conduction problem for a three-dimensional medium with cracks by the boundary element method. This technique allows to obtain the distribution of the temperature field and heat flux density at any point of the body under consideration, as well as to calculate the effective parameters of materials with high accuracy at relatively low calculation time using ordinary personal computers of average power. The basis of the numerical method presented in this paper is the decomposition of the desired solution into a series of some pre-calculated analytical solutions of the heat conduction equations. The dependence of the effective thermal conductivity on the density of thermally insulated cracks was considered. The formula of this dependence is proposed. Verification of the proposed methodology was carried out by comparing the numerical results of a number of problems with the results of other authors.

Relaxation dynamics and conductivity in poly(vinylidene fluoride)/graphene oxide composites

The αc relaxation, which originates from the crystalline phase of Poly(vinylidene fluoride), is studied in the composite system of Poly(vinylidene fluoride) and Graphene oxide. PVDF/GO composites were prepared using solvent casting. The crystalline phases in PVDF/GO composites were identified using XRD and quantified using FTIR. The thermal properties were analyzed using DSC, and the crystallization degrees were calculated. The electric modulus formalism is employed to understand the relaxation mechanism with temperature. AC conductivity studies reveal the activation energy for conduction in these composites.

Nerve conduction studies of sensory nerves with proven vasculitic neuropathy often show an absent electrical response.

In vasculitic neuropathy (VN), it is not known whether nerve conduction studies (NCSs) showing low amplitude sensory nerve action potentials (SNAPs) or those with absent responses have a higher yield in detecting appropriate nerves for pathological confirmation. Our goal was to describe NCS findings of nerves prior to biopsy in patients with VN. We performed a retrospective study between January 2000 and April 2021 in patients with VN who either met pathological definite criteria for VN or criteria for clinically probable VN and had NCS of the sural or superficial radial sensory nerves prior to biopsy of the same nerve. We included 61 patients with VN. The pathological findings showed 37 (60.7%) definite, 14 (23%) probable, and 2 (3.3%) possible VN; eight (13%) samples did not meet Peripheral Nerve Society pathological criteria. Most patients who met definite (20 out of 37, 54%) and probable (9 out of 14, 64%) VN pathological criteria had absent SNAPs. Only three out of eight (37.5%) patients without VN pathological findings had absent SNAPs. There was no statistically significant correlation between pathological diagnosis and SNAP amplitude (χ2 = 1.98, p = .58). Additionally, no association was found between VN pathological criteria and use of immunomodulatory treatment (p = .67) or corticosteroids (p = .52). Most nerves with pathological VN findings showed no response on NCS. In patients with suspected VN, sural or superficial radial sensory nerves with absent responses on NCS are adequate biopsy targets as compared to nerves in which SNAPs can be recorded.

Prognostic Value of Early Nerve Conduction Studies in Suspected Guillain-Barré Syndrome in Pediatric Age Group: An Observational Study

Prognostic Value of Early Nerve Conduction Studies in Suspected Guillain-Barré Syndrome in Pediatric Age Group: An Observational Study

Comparing the efficacy of multiple quantitative and qualitative ultrasound parameters for the diagnosis of carpal tunnel syndrome.

Carpal tunnel syndrome (CTS) is a compression neuropathy causing significant morbidity. Over the years, ultrasound has been evaluated as an alternative to nerve conduction study (NCS) for diagnosing CTS, however, there is no consensus as to which ultrasound parameter is the best. Our study aimed to determine and compare the efficacy of various ultrasound-based variables for diagnosis of CTS. 80 patients with clinical suspicion of CTS underwent ultrasound examination with calculation of cross-sectional area (CSA), delta CSA, wrist forearm ratio (WFR), palmer bowing (PB), flattening ratio (FR), flexor retinaculum thickness (FT), and evaluation of echogenicity and vascularity of median nerve. NCS was taken as the gold standard and the diagnostic efficacy of all these variables was compared, followed by receiver operator curve (ROC) analysis. Delta CSA had the highest accuracy (91.25%), followed by CSAc (80%), WFR (78.75%), and PB (73.75%). Youden's index and sensitivity were highest for delta CSA (0.783 and 96.15% respectively), while specificity was highest for FT (89.29%). The highest area under the curve was noted for delta CSA (97.1%), followed by WFR (AUC = 87.4%) and CSAc (AUC = 86.0%). Delta CSA was found to be the best ultrasound parameter for diagnosis of CTS, followed by CSAc, WFR, and PB, and can be used as an alternative to NCS. Using ROC analysis this study also predicted the best cut-off values for these parameters which could improve their diagnostic accuracy and further research is needed to confirm these findings.

Electrophysiological Changes in Median Nerve among Young Male Cigarette Smokers

Background: Cigarette smoking has been associated with numerous cardiovascular and respiratory disorders. Chronic smoking may also disrupt neuronal function and damage neurons in the peripheral nervous system. Median nerve conduction study is an important electrodiagnostic test for the detection of peripheral nerve dysfunction. Objectives: To observe the impact of cigarette smoking on the electrophysiological status of median motor and sensory nerves in apparently healthy male cigarette smokers. Materials and Methods: This case-control study was carried out in the Department of Physiology, Sir Salimullah Medical College, Dhaka, from July 2017 to June 2018 on thirty male cigarette smokers aged 25 to 40 years. For comparison, thirty age and BMI matched non-smoker healthy male subjects were selected as controls. Motor and sensory nerve conduction parameters (latency, amplitude and nerve conduction velocity) of right median nerve were evaluated by standard methods, using standard nerve conduction study and electromyography machines in the Department of Neurology, Dhaka Medical College Hospital. For statistical analysis, unpaired t test was performed. Results: In this study, median sensory nerve latency was significantly prolonged (p ˂ 0.001) and sensory nerve conduction velocity was significantly slower (p ˂ 0.001) in cigarette smokers. The mean amplitude was also slightly reduced in smokers, but statistically, it was insignificant. However, the distal latency of median motor nerve was slightly prolonged whereas, the amplitude and motor nerve conduction velocity were slightly reduced in cigarette smokers in comparison to those of non-smokers. But the differences were not statistically significant. In addition, 10% of cigarette smokers had subclinical impairment in median sensory nerve function. Conclusion: Chronic cigarette smoking induces significant electrophysiological changes in median sensory nerve fibers and causes sensory nerve dysfunction, while it does not markedly affect median motor nerve fibers in young individuals. KYAMC Journal Volume: 15, No: 01, April 2024: 03-07.