Latency Ratio Research Articles

An optimized deep neural network based DoS attack detection in wireless video sensor network

Due to the technological advancements in sensor and modern devices, the Wireless Multimedia Sensor Network (WNSMs) have gained attraction among various communities. It makes it firm and remarkable achievements in wireless communication, media transfer and digital transmission by adopting portable technologies. In recent decades, in applications such as agriculture and industry the sensor nodes are intended to measure the parameters such as temperature, moisture content and other environmental factors. WNSMs have also facilitates the applications by providing the devices with self-governing access for sending and processing the data associated with suitable audio and video information.Numerous video sensor network researches focus on reducing power consumption and optimizing transmission capacity, but data reliability is the real need. The hindrance involved in the sensor nodes result into various attacks on WMSN especially Denial of Service (DoS) attacks. The core of this attack is to incapacitate proper functioning of the network. Both Attacker and attackers, focus on attacking and preventing the legitimate network nodes from using the network resources. Distributed attack is defined as the network which is being attacked by multiple attackers. This type of attack causes significantly more issues in functionality of the network than attacks involved on a single node. Redemption of the network from the threats of DoS attacks, an enhanced machine learning algorithm has to be presented. For detecting DoS in WMSN an optimized Deep Neural Network algorithm is proposed. The parameters required are chosen from adaptive particle swarm optimization algorithm. The approach’s efficiency to be measured by the ratio of packet transmission, energy consumption, latency, network length, and throughput.

Working memory and mild cognitive impairment: Digital intra‐response latency, subcortical nuclei, and neuropsychological test performance

AbstractBackgroundDigital technology offers the ability to obtain nuanced data previously unobtainable. A digital Backward Digit Span (BDT) using voice recognition was administered to memory clinic patients. Our goal was to assess the validity of this technology by (1) analyzing differences between non‐MCI versus MCI patients; (2) examining correlations with other neuropsychology tests; and, (3) analyzing test performance in relation to MRI subcortical regions of interest known to be related to working memory.MethodJak‐Bondi (2009) criteria classify patients into MCI (n= 67) and non‐MCI (n= 72) groups. Working memory (WM) was assessed with the Backward Digit Span Test (BDT) consisting of 7 trials of 5 digits backwards; all trials were administered; and comprehensive neuropsychological testing was obtained. Only correct test trials were analyzed. BDT variables of interest included latency for each five responses. NeuroquantTM software calculated thalamic, caudate and hippocampal volume (n= 23) controlled for intracranial volume (ICV).ResultBetween‐group difference for total time to completion was not significant (M= 55.64 + 18.91 sec.). An analysis of serial order position latencies clearly suggests two distinct epochs (Figure 1). A latency ratio (LR) for serial order 1 versus serial order 3 was calculated. Using this measure, non‐MCI patients presented with slower latency to initiate their response (serial order 1); but faster latency to sustain their response (serial order 3) compared that MCI patients (F[1,52]= 6.26, p< .016). Simple correlations were significant between the BDT‐LR and Judgement of Line Orientation Oblique test items (r= 0.325, p< .019) and WAIS‐III Digit Symbol test performance (r= 0.316, p< .017). Simple correlations were significant or near significant between the BDT‐LR and left thalamic volume (r= 0.468, p< 0.032); right thalamic volume (0.410, p< .065); total thalamic volume (r= 0.470, p< 0.032); and left caudate volume (r= 0.447, p< .042).ConclusionThese data are remarkable for how patients allocate their time to generate a correct response. Correlations between BDT‐LR, subcortical nuclei, and neuropsychological test performance provide evidence for the validity of using discrete latency measures to assess WM in patients with MCI. Intra‐response BDT latency ratios could be a meaningful neurocognitive biomarker for emergent illness.

Cervical vestibular evoked myogenic potentials in patients with the first episode of posterior canal benign paroxysmal positional vertigo before and after repositioning

Background Cervical vestibular evoked myogenic potentials (cVEMPs) are used to assess the sacculo-collic pathways. Benign paroxysmal positional vertigo (BPPV) is mainly a utricular disorder. Objectives To investigate cVEMPs in BPPV patients before and after repositioning maneuvers. Methods Forty patients with posterior canal BPPV with new onset symptoms underwent cVEMP testing at the time of diagnosis and a month after successful repositioning maneuver. p13, n23 latency and amplitude ratio values were compared with the results of 40 healthy controls. Results p13 and n23 latencies of the affected side were significantly longer than the healthy controls more prominent for the p13 latency. Comparison of the affected side with the non-affected side revealed delayed p13 latency on the affected side. Though a significant improvement in p13 latency was observed after repositioning, it was still prolonged when compared with the healthy controls. An abnormality regarding amplitudes was not present. Conclusions and significance cVEMP abnormalities in patients with BPPV indicate saccular dysfunction accompanying utricular dysfunction which seems to be confined to the symptomatic side at least in the early phase of the disease. Partial recovery can be seen after treatment with residual findings following even the first attack.

Association of long-term exposure to ambient air pollutants with prolonged sleep latency: The Henan Rural Cohort Study

BackgroundProlonged sleep latency is associated with far-reaching public health consequences. Although evidence about the effect of air pollution on sleep problem has been shown, the effect on sleep latency remained unknown. The study aimed to analyze the association between long-term exposure to air pollution and prolonged sleep latency in rural China. MethodsIn all, 27935 participants were included in the study from Henan Rural Cohort Study. A satellite-based spatiotemporal model was used to evaluate the 3-year average concentration of air pollutants at the home address of participants before the baseline survey. Air pollutants included NO2 (nitrogen dioxide), PM1 (particulate matter with aerodynamic diameters ≤1 μm), PM2.5 (particulate matter with aerodynamic diameters ≤ 2.5 μm), and PM10 (particulate matter with aerodynamic diametes ≤ 10 μm). A logistic regression model was conducted to assess the odds ratio (OR) and 95% confidence interval (95% CI) between air pollutants and prolonged sleep latency. ResultsThere were 5825 (20.85%) participants with prolonged sleep latency. The average concentration of NO2, PM1, PM2.5, and PM10 were 38.22 (2.54) μg/m3, 56.29 (1.75) μg/m3, 72.30 (1.87) μg/m3, and 130.01 (4.58) μg/m3. The odds ratio (95%CI) of prolonged sleep latency with an IQR increase of NO2, PM1, PM2.5, and PM10 were 1.59 (1.33–1.90), 1.23 (1.13–1.33), 1.28 (1.13–1.45) and 1.43 (1.22–1.67). The stratified analysis showed the effect of air pollutants was stronger among those with stroke. ConclusionLong-term exposure to NO2, PM1, PM2.5 and PM10 were associated with prolonged sleep latency. The adverse impact of air pollution should be considered when treating sleep problems.

The clinical study of ocular vestibular evoked myogenic potential on three eye positions

Objective: To analyze the characteristics of the ocular vestibular evoked myogenic potential on three different eye positions and to explore the appropriate eye position for oVEMP. Methods: 15 patients (30 ears) with vertigo who underwent oVEMP test from December 2017 to May 2018 were selected as the patient group, including seven males and eight females, with an average age of (51±13) years. Another 22 (44 ears) healthy young people were recruited into the control group, including 10 males and 12 females, with an average age of (23±5) years. oVEMPs were measured on the following three eye positions respectively: 30 degrees straight up(upper median position),45 degrees upper right(upper right position), and 45 degrees upper left(upper left position). oVEMP elicitation rate, oVEMP latencies, amplitudes and interaural amplitude asymmetry ratio were analyzed by SPSS 23.0 statistical software. Results: There was no statistical significance (P>0.05) in the oVEMP elicitation rate, oVEMP latency, amplitude and asymmetry ratio on the three eye positions among the control group, the patient group and the overall subjects. Conclusions: The three eye positions can be used to detect oVEMP in clinic. There is no difference in the extraction rate and waveform characteristics. When one of the eye positions is difficult to gaze or not easy to obtain the coincidence curve, the other two can be used to obtain the ideal oVEMP curves as well.

Modeling Remapping Based Fault Tolerance Techniques for Chip Multiprocessor Cache with Design Space Exploration

On top of the wear-out failures and external particle interventions, voltage scaling to mitigate the power consumption in multiprocessor makes cache more vulnerable to cell failures. For the indispensable voltage reduction to prolong the battery life of handheld devices, fault tolerance techniques are extremely important to ensure fault free execution in near-threshold voltage. Several fault tolerance techniques have been proposed and the remapping based techniques are found to be effective to address the issue of fault tolerance in single core systems. This work proposes an analytical model for remapping based fault tolerance techniques to evaluate the effectiveness of such schemes in multicore systems. The metrics Expected Miss Ratio in Multicore (EMRMC) and Expected Latency Ratio in Multicore (ELRMC), are introduced to characterize the behavior of remapping based techniques. The EMRMC and ELRMC are defined as the function of probability of cell failure (Pfail), block size, number of cores and threads. The system is simulated in Multi2sim 5.0, a multicore CPU-GPU simulator. The values of the metrics for different configuration parameters like probability of cell failure, number of cores, number of blocks, block size and number of threads are analysed for framing the guidelines of system configuration to deliver better performance in remapping based fault tolerance. It is observed that the EMRMC is proportional to Pfail and block size but inversely proportional to the number of cores and threads and it is not affected by the number of blocks. On the contrary, the ELRMC is inversely proportional to Pfail and block size and proportional to the number of cores and threads. It is also observed that the ELRMC is independent of the number of cores and blocks. EMRMC is best minimized for Pfail ≤ 1e-4, block size ≤ 64 bytes, number of cores ≥ 4 and number of threads ≥ 2. On the other hand, ELRMC is best observed for Pfail ≤ 1e-4, block size ≥ 64 bytes, number of cores ≥ 4 and number of threads 2.

Cervial vestibular-evoked myogenic potential induced by galvanic vestibular stimulation in normal people

Objective:To establish a new method for detecting vestibular function by testing cervical vestibular-evoked myogenic potential induced by galvanic vestibular stimulation in normal population. Method:Twenty normal ears were tested for cervical vestibular evoked myogenic potential induced by galvanic vestibular stimulation. SPSS 18.0 software was used to analyze the obtained data. Result:In all healthy subjects mastoid-forehead galvanic vestibular stimulation produced a positive-negative biphasic EMG responses on SCM ipsilateral to the cathodal electrode. The latency of p13 was（11.52±3.05） ms. The latency of n23 was（15.31±3.38） ms. The amplitude of p13-n23 was（40.55±27.93） μV. The interval of p13-n23 was（3.53±1.38） ms. The interaural asymmetry ratio（AR, %） of p13, n23 latency, the amplitude and interval were respectively（6.96±6.79）%, （6.47±5.93）%, （28.08±26.42）% and （16.61±11.11）%. There was no significant difference in all parameters between the right and left ears of all subjects. Conclusion:The value of cervical vestibular-evoked myogenic potential induced by galvanic vestibular stimulation in normal subjects can be established to explore methods for diagnosis, treatment and researching mechanism of auditory neuropathy and vestibular neuropathy.

Enhanced cache sharing through cooperative data cache approach in MANET

In a mobile ad hoc network (MANET) under normal cache sharing scenarios, when the data is transmitted from source to destination, all the nodes along the path store the information on the cache layer before reaching the destination. This may result in increased node overhead, increased cache memory utility and very high end-to-end delay. In this paper, we propose an enhanced cache sharing through cooperative data cache (ECSCDC) approach for MANETs. During the transmission of desired data from the data centre back to the request originator, the data packets will be cached by the intermediate caching nodes only if required, by using the asymmetric cooperative cache approach. Those caching nodes that can retain the data in its cache, for future data retrieval is selected based on scaled power community index. By simulation results, we show that the proposed technique reduces the communication overhead, access latency and average traffic ratio near the data centre while increasing the cache hit ratio.

Vestibular evoked myogenic potential (VEMP) results in migraine and migrainous vertigo

Background: The pathophysiology of vertigo is not fully known; thus, it is difficult to diagnose vestibular migraine (VM) in some migraine patients with vertigo symptoms.Aims/objectives: We aimed to evaluate the diagnostic value of cervical vestibular evoked myogenic potential (cVEMP) in patients with VM.Materials and Methods: Thirty-two patients diagnosed with migraine and 31 patients with VM were prospectively included in this study. The cVEMP responses were obtained, and P1-N1 latency, interpeak amplitude, amplitude asymmetry ratio were calculated. The patients' demographics, results of physical and audiometric examinations, and VEMP records as well as absence of responses were evaluated and compared between groups.Results: The incidence of ears with absence VEMP responses was found to be numerically higher in the migraine group than in the VM group (p = .106). Additionally, there were no statistically significant differences detected between the groups in terms of the p13 or n23 latency, interpeak amplitude, and amplitude asymmetry ratio measured in both right and left ears (p > .05).Conclusions: The increased rate of absent VEMPs was associated with the hypoperfusion of the sacculo-collic reflex pathway in migraine patients. In addition, it was concluded that VEMP reflex responses appear to be insufficient to differentiate between VM and migraine diagnoses.

Least Mobility High Power (LMHP) Dynamic Routing for QoS Development in Manet

The problem of routing in mobile adhoc network has been approached in different methods. However, they suffer to achieve the required performance in quality of service. The mobile nodes spent most of the energy on routing because of cooperative transmission. To improve the performance of mobile adhoc network, an efficient LMHP routing algorithm is proposed in this paper. The source node discovers the route by sending LMHP route discovery (LMHP-RD) message to all its neighbors, identified in the neighbor discovery phase. The neighbors reply the LMHP-route request (RREQ) packet to the source node which contains power and displacement information about the intermediate nodes. The source node collects the information about the routes available along with power and displacement details. Using the identified information, the source node computes the transmission completeness weight for each route. Based on computed transmission completeness weight, the method selects a single route with maximum weight to perform data transmission. This method improves the throughput performance and increases the lifetime of the network. The proposed system is developed and simulated in NS2 and the performance has been analyzed based on three metrics Throughput, pocket delivery ratio and latency ratio. The simulated results show that the power consumption is relatively low in the proposed method, comparing the available techniques.

Analysis of Price of Total Anarchy in Congestion Games via Smoothness Arguments

Efficiency loss may exist at every stage of repeated play. With the rapid development of our society, how to improve the overall efficiency in repeated games becomes increasingly crucial. This paper studies the performance of a sequence of action profiles generated by repeated play in a multiple origin-destination network. To analyze the overall efficiency of these action profiles, the price of total anarchy (POTA), defined as the worst-case ratio of the average total latency over a period of time and the total latency of any optimal strategy, is adopted. First of all, it is shown that the sequence of action profiles generated by best response principle with inertia possesses almost sure no-regret property. Then, we identify the upper bound of POTA via smoothness arguments for both linear and nonlinear latency cases. After that, we analyze the effect of road pricing on POTA in traffic networks with linear latency function. It is shown that the road price we designed can reduce the upper bound of POTA compared with that without road price. In addition, how the inaccurate parameter information of the latency function affects the POTA is discussed for the linear latency case. Moreover, in a traffic network with heterogeneous players, we show that the upper bound of POTA is the same as that in a network with homogeneous players as time goes to infinity. Finally, the results are applied to a traffic routing problem based on the real traffic data of Singapore.

Poster 31: Diagnostic Value of Segmental Study with Distoproximal Latency Ratio for Carpal Tunnel Syndrome

PM&RVolume 9, Issue 9S1 p. S150-S150 General Rehabilitation Poster Hall: Original Research Poster 31: Diagnostic Value of Segmental Study with Distoproximal Latency Ratio for Carpal Tunnel Syndrome Ki Un Jang, Ki Un Jang Gangnam Sacred Heart Hosp., Hallym University Medical College, Seoul, South Korea, Korea, Republic OfSearch for more papers by this authorJee Hee Jo MD, Jee Hee Jo MD Gangnam Sacred Heart Hosp., Hallym University Medical College, Seoul, South Korea, Korea, Republic OfSearch for more papers by this author Ki Un Jang, Ki Un Jang Gangnam Sacred Heart Hosp., Hallym University Medical College, Seoul, South Korea, Korea, Republic OfSearch for more papers by this authorJee Hee Jo MD, Jee Hee Jo MD Gangnam Sacred Heart Hosp., Hallym University Medical College, Seoul, South Korea, Korea, Republic OfSearch for more papers by this author First published: 19 September 2017 https://doi.org/10.1016/j.pmrj.2017.07.069Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume9, Issue9S12017 AAPM&R Annual Assembly AbstractsSeptember 2017Pages S150-S150 RelatedInformation

Effects of pharmacological gap junction and sodium channel blockade on S1S2 restitution properties in Langendorff-perfused mouse hearts

Gap junctions and sodium channels are the major molecular determinants of normal and abnormal electrical conduction through the myocardium, however, their exact contributions to arrhythmogenesis are unclear. We examined conduction and recovery properties of regular (S1) and extrasystolic (S2) action potentials (APs), S1S2 restitution and ventricular arrhythmogenicity using the gap junction and sodium channel inhibitor heptanol (2 mM) in Langendorff-perfused mouse hearts (n=10). Monophasic action potential recordings obtained during S1S2 pacing showed that heptanol increased the proportion of hearts showing inducible ventricular tachycardia (0/10 vs. 5/8 hearts (Fisher’s exact test, P < 0.05), prolonged activation latencies of S1 and S2 APs, thereby decreasing S2/S1 activation latency ratio (ANOVA, P < 0.05) despite prolonged ventricular effective refractory period (VERP). It did not alter S1 action potential duration at 90% repolarization (APD90) but prolonged S2 APD90 (P < 0.05), thereby increasing S2/S1 APD90 ratio (P < 0.05). It did not alter maximum conduction velocity (CV) restitution gradient or maximum CV reductions but decreased the restitution time constant (P < 0.05). It increased maximal APD90 restitution gradient (P < 0.05) without altering critical diastolic interval or maximum APD90 reductions. Pro-arrhythmic effects of 2 mM heptanol are explicable by delayed conduction and abnormal electrical restitution. We concluded that gap junctions modulated via heptanol (0.05 mM) increased arrhythmogenicity through a delay in conduction, while sodium channel inhibition by a higher concentration of heptanol (2 mM) increased arrhythmogenicity via additional mechanisms, such as abnormalities in APDs and CV restitution.

Analysis of KDD CUP Dataset Using Multi-Agent Methodology with Effective Fuzzy Based Intrusion Detection System

ABSTRACTSecure environment construction against the several intrusions is an attractive research area in Wireless Sensor Network (WSN) and Mobile Ad-hoc Network (MANET)-based real-time applications. Intrusion Detection System (IDS) evolved in network research studies improves the security and protects the resources from the various intrusions. The centralized and the distributed IDS are the major IDS categories. The central point failure in centralized IDS under heavy load introduces the security issues. The centralized system deficiency and hierarchical nature introduces the agent-based IDS. This article proposes the Multi-Agent IDS to detect the packet transmission failures and anomaly behavior in two different datasets namely KDD cup 1999 and the real-time traffic dataset. The Multi-Agent Based IDS (MAIDS) employs the distance and density-based algorithms for cluster formation. The rules formation in either association or sequential manner detects and classifies the attacks to the respective agent. Finally, the fuzzy-rules formulation in MAIDS predicts the intrusion type. The comparative analysis between the MAIDS and Network Intrusion Detection System (NIDS) regarding latency, overhead, and packet delivery ratio conveys that the MAIDS provided the better performance than the NIDS.

Enhancement of Asynchronous MAC Protocol in Wireless Sensor Networks for Smart Monitoring Applications

Up to now, many research works have been focusing on designs in MAC layer of Wireless Sensor Networks (WSNs) to target high throughput, low latency and solving the problem of idle listening. In this paper, an enhancement of Low-power asynchronous protocol for MAC layer, namely E-MAC, is proposed to target a long lifetime of sensor nodes working 6LoWPAN/IPv6 networks. Moreover, the E-MAC protocol is implemented on TI low-power platforms to verify the efficiency of the proposed design. Several parameters such as energy consumption, latency and packet delivery ratio are simulated and measured in a real monitoring test-bed to show the better performance in comparison with other popular MAC protocols.

Terminal latency abnormality in amyotrophic lateral sclerosis without split hand syndrome

Amyotrophic lateral sclerosis (ALS) has a peculiar involvement pattern; clinically it is known as split hand syndrome and electrophysiologically shows abnormalities in the abductor pollicis brevis (APB)/abductor digiti minimi (ADM) ratio. The aim of this study was to find a significant electrophysiological parameter in upper limb onset ALS patients with normal APB/ADM ratio when compared to cervical spondylotic amyotrophy (CSA) and healthy controls. We retrospectively reviewed the electrophysiological results of 47 upper limb onset ALS and 42 CSA cases; 20 healthy individuals were included as controls. We included ALS and CSA patients with normal ADM/APB ratio (≥0.6, and ≤1.7), and the parameters of electrophysiological study were compared. The electrophysiological parameters of statistical significance among ALS, CSA and normal controls were: amplitude of median and ulnar nerves, the terminal latency of median nerve, F-wave latency of median and ulnar nerves, terminal latency ratio of ulnar/median nerves, and F-wave latency ratio of ulnar/median nerves (p<0.05). Among these parameters, the terminal latency ratio of ulnar/median nerve and terminal latency of median nerve in ALS were significantly different with both of CSA and normal control (p<0.006). The abnormality in the terminal latency of the median nerve can be partly explained by the distal motor axonal dysfunction due to sodium and potassium channel abnormalities. The hypothesis of distal axonopathy is known to play an important role in the pathogenesis of ALS causing a significant prolongation of the terminal latency in the median nerve and the ulnar/median nerve ratio.

Hierarchical content caching in fog radio access networks: ergodic rate and transmit latency

In order to alleviate capacity constraints on the fronthaul and decrease the transmit latency, a hierarchical content caching paradigm is applied in the fog radio access networks (F-RANs). In particular, a specific cluster of remote radio heads is formed through a common centralized cloud at the baseband unit pool, while the local content is directly delivered at fog access points with edge cache and distributed radio signal processing capability. Focusing on a downlink F-RAN, the explicit expressions of ergodic rate for the hierarchical paradigm is derived. Meanwhile, both the waiting delay and latency ratio for users requiring a single content are exploited. According to the evaluation results of ergodic rate on waiting delay, the transmit latency can be effectively reduced through improving the capacity of both fronthaul and radio access links. Moreover, to fully explore the potential of hierarchical content caching, the transmit latency for users requiring multiple content objects is optimized as well in three content transmission cases with different radio access links. The simulation results verify the accuracy of the analysis, further show the latency decreases significantly due to the hierarchical paradigm.

Ocular vestibular evoked myogenic potential testing for the prognosis of Bell’s palsy

Conclusion: oVEMP could be a useful tool for predicting the prognosis of Bell's palsy comparable to ENoG and H–B grade.Objectives: Several previous studies have reported cases of Bell’s palsy with vestibular function disorder. The basic hypothesis behind this effect lies in the close proximity of the vestibular and facial nerves in the internal auditory canal (IAC). Therefore, the aim of this study was to investigate the correlation between Bell’s palsy prognosis and ocular vestibular evoked myogenic potentials (oVEMPs).Methods: Total 104 consecutive patients who were diagnosed with Bell?s palsy from January 2012 to December 2014 were enrolled. Patients were divided into complete recovery group and incomplete recovery group. All of patients underwent oVEMP recordings within 1 week after disease onset. For the evaluation of correlation between H–B grades, ENoG, oVEMP and Recovery of Bell?s palsy, logistic regression analysis was performed.Results: The mean value of ocular vemp asymmetry was significantly higher in the incomplete recovery group than the complete recovery group (p < 0.05). No association was found between the ipsilesional PTA threshold, caloric test, and rate of abnormal EMG and recovery state. However, the initial state of ENoG, initial H–B grade, and oVEMP abnormal findings (Latency & Amplitude symmetry ratio) were significantly correlated with the rate of recovery (p = 0.025, p = 0.013, and p < 0.005, respectively).

Correlations of neurophysiological features with clinical manifestation in patients with diabetic peripheral neuropathy

Objective To explore the correlation of electrophysiological features with clinical manifestation in patients with diabetic peripheral neuropathy(DPN). Methods The clinical data of 306 patients with DPN undergoing nerve conduction study (NCS) during May 2013 to June 2015 were retrospectively analyzed. Among 306 patients, 304 were type 2, and 2 were type 1 diabetes with a mean age of 64.1 years and disease duration of 1 week-31 years. The relationship between the electrophysiological features and clinical manifestations was evaluated. Nerve conduction studies and F-wave and in sympathetic skin response were analyzed. Results ① NCS in lower limbs presented more abnormalities than that in upper limbs. There was the highest prevalence of not elicited sensory potential in Tibial nerve [56.9%(174/306), χ2=175.9] and the highest prevalence of not elicited motor potential in peroneal nerve [7.8%(24/306), χ2=1 103.1]. Amplitude abnormality was more severe in sensory nerve than that in motor nerve [41.4%(507/1 224) vs. 10.8%(132/1 224), χ2=559.2]. The ratio of abnormal motor conduction velocity or distal latency was higher than that of amplitude decreased [22.9%(280/1 224) vs. 10.8%(132/1 224), χ2=1 077.4]. ② The abnormal ratios of the shortest F-wave latency was lower than that of the prolonged distal latency in median and tibial nerve [5.4%(33/612) vs. 20.6%(126/612), χ2=607.6]. ③ The abnormal ratio of sympathetic skin response (SSR) in lower limbs were higher than that of upper limbs [40.2%(246/612)vs. 27.3%(167/612), χ2=129.4, P<0.001], abnormal ratio of amplitude was higher than that of the prolonged latency [30.1%(368/1 224) vs. 4.7%(58/1224), χ2=1 040.5, P<0.001]. Among the 99 cases presenting abnormal SSR in upper limbs, 32 cases were normal in conventional NCS. Among the 127 cases presenting abnormal SSR in lower limbs, 7 cases were normal in conventional NCS. ④Disease course and glycosylated hemoglobin values were positively correlated with the distal motor latency, and negatively correlated with the nerve conduction velocity and amplitude. Conclusion Electrophysiological features of DPN is mainly shown in axon of the distal sensory nerve. Long duration and hyperglycemia may lead to more abnormalities in electrophysiological tests. Key words: Diabetic neuropathies; Peripheral nerves; Neural conduction studies; Electrophysiology

Correlation between muscle electrophysiology and strength after fibular nerve injury.

Muscle strength measurement is important when evaluating the degree of impairment in patients with nerve injury. However, accurate and objective evaluation may be difficult in patients with severe pain or those who intentionally try to avoid full exertion. We investigated the usefulness of the affected-to-unaffected side electrophysiological parameter ratios as a measure of objective ankle dorsiflexion (ADF) strength in patients with unilateral fibular nerve injury (FNI). ADF strength was measured in patients with FNI via handheld dynamometer and manual muscle test (MMT). Fibular nerve compound muscle action potential (CMAP) amplitude and latency and ADF strength of the affected side were presented as ratios to the corresponding measurements of the unaffected side. We analysed the correlation of the CMAP ratio with the ADF strength ratio using a dynamometer and compared the CMAP ratios according to MMT grade. Fifty-two patients with FNI were enrolled. The mean CMAP latency ratio did not differ between MMT groups (p=0.573). The CMAP amplitude ratio proportionally increased with the quantified ADF strength ratio via dynamometer increase (ρ=0.790; p<0.001), but the CMAP latency ratio and the quantified ADF strength ratio did not significantly correlate (ρ=0.052; p=0.713). The average CMAP amplitude ratio significantly differed between MMT groups (p<0.001), and post hoc tests showed significant differences in all paired comparisons except of Fair and Good grades (p=0.064). Electrophysiological parameter ratio, such as the affected-to-unaffected side CMAP amplitude ratio, might be sensitive parameters for ADF power estimation after FNI.