A robust multi-branch multi-attention-mechanism EEGNet for motor imagery BCI decoding.

BACKGROUND: Motor-Imagery-based Brain-Computer Interface (MI-BCI) is a promising technology to assist communication, movement, and neurological rehabilitation for motor-impaired individuals. Electroencephalography (EEG) decoding techniques using deep learning (DL) possess noteworthy advantages due to automatic feature extraction and end-to-end learning. However, the DL-based EEG decoding models tend to show large variations due to intersubject variability of EEG, which results from inconsistencies of different subjects' optimal hyperparameters. NEW METHODS: This study proposes a multi-branch multi-attention mechanism EEGNet model (MBMANet) for robust decoding. It applies the multi-branch EEGNet structure to achieve various feature extractions. Further, the different attention mechanisms introduced in each branch attain diverse adaptive weight adjustments. This combination of multi-branch and multi-attention mechanisms allows for multi-level feature fusion to provide robust decoding for different subjects. RESULTS: The MBMANet model has a four-classification accuracy of 83.18% and kappa of 0.776 on the BCI Competition IV-2a dataset, which outperforms other eight CNN-based decoding models. This consistently satisfactory performance across all nine subjects indicates that the proposed model is robust. CONCLUSIONS: The combine of multi-branch and multi-attention mechanisms empowers the DL-based models to adaptively learn different EEG features, which provides a feasible solution for dealing with data variability. It also gives the MBMANet model more accurate decoding of motion intentions and lower training costs, thus improving the MI-BCI's utility and robustness.

Análisis de los parámetros ecográficos descritos en el estudio del síndrome del túnel del carpo. Una revisión sistemática / Analysis of the echographic parameters described in the study of carpal tunnel syndrome: A systematic review

El síndrome del túnel del carpo (STC) es la mononeuropatía por atrapamiento más frecuente; el diagnóstico se establece mediante pruebas electrodiagnósticas con un número sustancial de falsos positivos/negativos. Presentamos la siguiente revisión sistemática, cuyo objetivo es analizar la literatura más reciente en relación con los parámetros ecográficos descritos para estudiar el STC. Seleccionamos estudios que evaluasen parámetros ecográficos en pacientes con sospecha clínica, siguiendo las recomendaciones del manual Cochrane; incluimos revisiones sistemáticas, metaanálisis, estudios caso-control y de pruebas diagnósticas, valorando estudios retrospectivos y revisiones bibliográficas con buena calidad metodológica. La revisión se hizo de artículos publicados entre 2005-2019. Incluimos 8 artículos (2 revisiones sistemáticas/metaanálisis, 2 estudios caso-control, un estudio de pruebas diagnósticas, 2 revisiones literarias y un estudio retrospectivo). Los parámetros analizados fueron el área de sección transversa del nervio mediano, el índice muñeca-antebrazo, el índice entrada-salida, el rango de adelgazamiento del nervio mediano, el abombamiento del retináculo flexor y la vascularización/movilidad. La evidencia actual permite afirmar que la ecografía tiene utilidad en el cribado del STC.(AU)

Carpal tunnel syndrome (CTS) is the most common entrapment mononeuropathy; the diagnosis is established by electrodiagnostic tests with until 34% of false positives/negatives. We present the following systematic review which objective is to analyze the most recent literature related to the ultrasound parameters described to study CTS. We selected studies that evaluated ultrasound parameters in patients with clinical suspicion following the Cochrane manual's recommendations. We include systematic reviews, meta-analyses, case–control studies and diagnostic tests, evaluating retrospective studies and bibliographic reviews with proper methodological quality. Articles published between 2005 and 2019. We included eight articles (two systematic reviews/meta-analyses, two case–control studies, one diagnostic test study, two literature reviews, and one retrospective). The parameters analyzed were cross-sectional area, wrist–forearm index, entry–exit index, thinning range, palmar bowing of the flexor retinaculum, and vascularity/mobility. Current evidence allows us to affirm that ultrasound is useful in screening for CTS.(AU)

Electrodiagnostic methods to verify Guillain-Barré syndrome subtypes in Istanbul: A prospective multicenter study.

BACKGROUND AND AIMS: This study aimed to identify the clinical characteristics and electrodiagnostic subtypes of Guillain-Barré syndrome (GBS) in Istanbul. METHODS: Patients with GBS were prospectively recruited between April 2019 and March 2022 and two electrodiagnostic examinations were performed on each patient. The criteria of Ho et al., Hadden et al., Rajabally et al., and Uncini et al. were compared for the differentiation of demyelinating and axonal subtypes, and their relations with anti-ganglioside antibodies were analyzed. RESULTS: One hundred seventy-seven patients were included, 69 before the coronavirus disease 2019 pandemic (April 2019-February 2020) and 108 during the pandemic (March 2020-March 2022), without substantial changes in monthly frequencies. As compared with the criteria of Uncini et al., demyelinating GBS subtype diagnosis was more frequent according to the Ho et al. and Hadden et al. criteria (95/162, 58.6% vs. 110/174, 63.2% and 121/174, 69.5%, respectively), and less frequent according to Rajabally et al.'s criteria (76/174, 43.7%). Fourteen patients' diagnoses made using Rajabally et al.'s criteria were shifted to the other subtype with the second electrodiagnostic examination. Of the 106 analyzed patients, 22 had immunoglobulin G anti-ganglioside antibodies (14 with the axonal subtype). They had less frequent sensory symptoms (54.5% vs. 83.1%, p = 0.009), a more frequent history of previous gastroenteritis (54.5% vs. 22.9%, p = 0.007), and a more severe disease as compared with those without antibodies. INTERPRETATION: Serial electrodiagnostic examinations are more helpful for accurate subtype diagnosis of GBS because of the dynamic pathophysiology of the disease. We observed no significant increase in GBS frequency during the pandemic in this metropolis.

Subjective and Objective Differences in Patients with Unilateral and Bilateral Carpal Tunnel Syndrome and the Role of Obesity in Syndrome Severity.

BACKGROUND: It remains unclear whether physiologic differences exist in musculoskeletal ultrasound nerve measurements when comparing bilateral and unilateral carpal tunnel syndrome (CTS) patients. Similarly, the influence of body mass index on CTS severity is not well characterized. METHODS: Unilateral and bilateral CTS patients were seen from October of 2014 to February of 2021. Obese and nonobese CTS patients were compared. Median nerve cross-sectional area (CSA), Boston Carpal Tunnel Syndrome Questionnaire (BCTSQ), and six-item Carpal Tunnel Symptom Score (CTS-6) measures were obtained. Nerve conduction studies recorded distal motor latency (DML) and distal sensory latency (DSL). Statistical analysis used Wilcoxon signed rank testing for paired continuous variables, Mann-Whitney U testing for nonpaired continuous variables, and chi-square testing for continuous variables, with a significance level of P < 0.05. RESULTS: A total of 109 (218 nerves) bilateral and 112 (112 nerves) unilateral CTS patients were reviewed. Bilateral patients had larger median nerve CSAs on their more symptomatic side, when defined by BCTSQ score ( P < 0.0001), CTS-6 score ( P < 0.0001), DML ( P < 0.0001), and DSL ( P < 0.01). Bilateral patients also had higher symptom severity scale ( P < 0.01) and DSL ( P < 0.001) outcomes compared with unilateral patients. Obese patients had higher median nerve CSA ( P < 0.01), prolonged DML, and prolonged DSL ( P < 0.0001) values despite similar CTS severity (BCTSQ and CTS-6). CONCLUSIONS: Ultrasound identifies the more symptomatic side in bilateral patients, which correlates with increasing severity (NCS and BCTSQ). Obesity increases median nerve CSA and prolongs nerve conduction studies without influencing CTS severity. This information can be used when considering which diagnostic test to order for CTS.

Electrodiagnostic findings in amyotrophic lateral sclerosis: Variation with region of onset and utility of thoracic paraspinal muscle examination.

INTRODUCTION/AIMS: Limited data exist regarding variation of electrodiagnostic (EDX) findings in amyotrophic lateral sclerosis (ALS) patients with different onset regions and specificity of thoracic paraspinal muscle (TPSP) examination for confirming a diagnosis of ALS. We aimed to demonstrate the variation of EDX features and characterize the utility of TPSP muscle examination in the electrodiagnosis of ALS. METHODS: This is a retrospective study of a large cohort of ALS patients who had a comprehensive EDX evaluation. RESULTS: The study included 448 patients; all fulfilled the Gold Coast criteria for ALS. The average age at the time of EDX study was 64 years, and 41.1% were women. The onset region was identified as follows: bulbar (N = 149), cervical (N = 127), lumbosacral (N = 162), and other (N = 10). In contrast to limb onset, bulbar-onset patients more frequently demonstrated a pattern of normal or near normal needle electromyography (EMG) (p < .0001) and less frequently had abnormalities on EMG of TPSP (p = .002). Clinical or EDX diagnosis of sensory polyneuropathy was present in 12.6% patients, more frequently in the lumbosacral onset subgroup (p < .03). EMG showed active denervation in 9.6% and chronic denervation in 59% of craniobulbar muscles examined, without observed difference among different onset regions. TPSP showed higher frequencies of active and chronic denervation in ALS than a group of patients with non-ALS neuromuscular disorders. DISCUSSION: EDX features may differ among ALS patients of different onset regions. TPSP EMG is highly useful in differentiating ALS from non-ALS neuromuscular disorders while the yield of craniobulbar muscles, especially for active denervation, is low.

Comparison of electrodiagnostic findings in acute traumatic versus chronic non-traumatic ulnar neuropathy at the elbow.

INTRODUCTION/AIMS: A common concept is that traumatic nerve injuries are more likely axonal, and that compressive neuropathies are more likely demyelinating. The purpose of this study was to compare traumatic versus non-traumatic ulnar neuropathy at the elbow (UNE) to look for electrodiagnostic differences between the two groups. METHODS: A retrospective 3 year review of UNE patients at two academic health science centers was conducted. Patients were grouped into acute traumatic UNE versus chronic non-traumatic UNE based on clinical history. Electrodiagnostic measurements were compared between the two groups. RESULTS: There were 50 subjects with acute traumatic UNE and 41 with chronic non-traumatic UNE. Mean age and sex distribution were similar but those with traumatic UNE had a 7 month duration of symptoms, while those with chronic UNE had 29 month duration (p < .001). All electrodiagnostic measurements were similar between the two groups including compound muscle action potential amplitudes, motor conduction velocities, frequency of conduction block, sensory nerve studies, and needle electromyography. DISCUSSION: We did not find a difference between the two groups. One should not make inferences regarding acuity or etiology based on electrodiagnostic features alone.

Training factors that influence electrodiagnostic medicine knowledge.

INTRODUCTION/AIMS: Self-assessment examinations (SAEs) help trainees assess their progress in education. SAEs also provide feedback to training programs as to how factors in training influence examination performance. This study's goal was to examine the relationship between the number of months of training in electrodiagnostic (EDx) medicine, the number of EDx studies during training, and scores on the American Association of Neuromuscular and Electrodiagnostic Medicine SAE. METHODS: This was a retrospective study of the 2023 AANEM-SAE results. In addition to the examination score, participants were asked approximately how many EDx studies they performed in training and how many months of training they had completed. Analysis included correlation of the examination scores with months of training as well as number of EDx studies. In addition, a multivariate linear regression model was developed. RESULTS: A total of 756 participants completed the proctored examination in May 2023. Examination score was moderately and positively correlated with the number of months of training (Pearson r = .5; p < .001) as well as the number of EDx studies during training (Pearson r = .55; p < .001). Scores steadily improved with additional months of training, but leveled off after 300-400 EDx studies. Regression analysis indicated that higher numbers of EDx studies were correlated with a higher examination score even after accounting for the number of months of study. DISCUSSION: We believe that a greater number of months of training is associated with better performance on the AANEM-SAE and that greatest improvement in examination performance occurs during the first 300-400 EDx studies.

The necessity of electrodiagnostic studies and ultrasound in ulnar nerve entrapment according to surgeons in the Netherlands.

BACKGROUND: Ulnar nerve entrapment at the elbow (UNE) is the second most prevalent entrapment neuropathy after carpal tunnel syndrome. The objective of this study was to evaluate the expert opinion of different surgical disciplines regarding the need for electrodiagnostic or ultrasound confirmation of UNE and, if so, which test was preferred for confirmation. METHODS: A questionnaire was sent to all neurosurgeons and plastic or hand surgeons in the Netherlands to evaluate the current practice in planning surgical treatment of UNE. RESULTS: The response rate was 36.4 % (134 out of 368). 94 % of surgeons reported that > 95 % of their patients had EDX or ultrasound studies before surgery. 80.6 % of all surgeons who responded reported that they seldom operated on UNE without electrodiagnostic confirmation. Hand surgeons (25.9 %) were more willing to operate on clinically diagnosed UNE without EDX than neurosurgeons (9.4 %) CONCLUSIONS: Dutch surgeons prefer diagnostic confirmation of UNE either by ultrasound or EDX, with a preference for EDX and the vast majority of operated patients do have either EDX or ultrasound or both before surgery. Compared to neurosurgeons, hand surgeons are more willing to operate on patients with clinically defined UNE but normal electrodiagnostic studies.

Diagnosis of Ulnar Neuropathy at the Elbow Using Ultrasound - A Comparison to Electrophysiologic Studies.

PURPOSE: Given the relatively high false negative rate of electrodiagnostic studies (EDX) in patients with clinically diagnosed ulnar neuropathy at the elbow (UNE), we sought to determine whether an alternative objective test could more effectively detect UNE. Additionally, we proposed to determine the relationship between the cross-sectional area (CSA) of the ulnar nerve on ultrasound (US), EDX, and clinical symptoms. METHODS: This was a retrospective study of patients presenting with symptomatic UNE. The performance characteristics of EDX versus ultrasound were calculated using the clinical diagnosis of UNE as the reference standard. Standard EDX studies and US of the ulnar nerve were analyzed. Maximal CSA of the ulnar nerve and EDX severity were analyzed for patients with each combination of US-positive/negative and EDX-positive/negative findings. RESULTS: Analysis was performed on 89 patients and 115 nerves with signs and symptoms of cubital tunnel syndrome. In total, 56 (49%) nerves were diagnosed as mild UNE, 32 (28%) nerves were diagnosed as moderate UNE, 17 (15%) nerves were diagnosed as severe UNE, and 10 (8%) nerves were negative for UNE by EDX. Maximal-maximal CSA was highly correlated with disease severity as determined by nerve conduction studies/electromyography. Compared with EDX+/US+, patients with EDX-/US+ showed higher rates of ulnar sensory loss and elbow tenderness with similar rates of positive Tinel and intrinsic muscle atrophy. In this sample of patients with clinically diagnosed UNE, 91.3% of the patients demonstrated positive EDX studies, whereas 94.8% had a positive US. CONCLUSIONS: Ultrasound is an alternative to EDX that could be incorporated clinically in the diagnosis and management of UNE. Ultrasound was able to consistently detect clinically positive cubital tunnel syndrome demonstrating its utility as a confirmatory or supplemental test to the clinical assessment if one is required. Ultrasound additionally may be able to better identify patients with early stages of UNE with negative EDX findings. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic IV.

Influence of Electrodiagnostic Studies on Surgery for Carpal Tunnel Syndrome: A Retrospective Analysis of Data from a Single Urban Institution.

Background: This study aimed to clarify the influence of preoperative electrodiagnostic (EDX) utilisation and its severity on surgically treated patients with carpal tunnel syndrome (CTS). Methods: This retrospective study analysed the data of patients who underwent CTS surgery at our facility from 2012 to 2022. Data regarding age, sex, affected side, diabetes mellitus, rheumatoid arthritis, haemodialysis and insurance type were collected, along with the following clinical information: utilisation of EDX, steroid injection, number of items of preoperative physical examination and history taking, intervals between symptom onset and the initial visit and between the initial visit and surgery, type of surgical procedure and surgery categorisation (primary or revision). EDX data (EDX severity, interval between EDX and surgery and concomitant nerve lesions) were also investigated. Univariate and multivariate analyses were conducted to assess the influence of EDX utilisation and severity on clinical parameters. Results: Of the 343 hands enrolled in our study, 304 (89%) underwent preoperative EDX assessment. EDX severity was classified as normal, mild, moderate or severe in 6 (2%), 18 (6%), 102 (34%) and 178 hands (58%), respectively. After the univariate and multivariable analyses, more items of preoperative physical examination and history taking were associated with non-EDX utilisation, whereas younger age, female sex and steroid injection were associated with milder EDX. Conclusions: Increased number of items of preoperative physical examination and history taking or steroid injection were independently associated with non-EDX utilisation or milder EDX, respectively, suggesting that when thorough clinical evaluation is conducted, hand surgeons may be less likely to request for EDX before surgery. Moreover, their treatment recommendation may be influenced by EDX severity. Level of Evidence: Level III (Diagnostic).

Neuromuscular electrodiagnosis.

The electrodiagnostic (EDX) study is an extension of the clinical examination, which means that the clinical features dictate the initial nerve conduction studies (NCS) performed. However, once the EDX study is started, it continues in an independent manner, meaning that the initial NCS findings dictate the subsequent studies performed. Because competent EDX study performance requires considerable knowledge (and special training), it is not possible to convey all of the basic and advanced concepts in a single chapter. Nonetheless, the most important concepts are easily conveyed by a discussion limited to EDX-pertinent anatomical, physiological, pathological, pathophysiological, and basic electrical concepts. The focus of this chapter will be on the standard NCS and needle EMG measurements made during EDX studies and their significance with regard to lesion localization and characterization. Because the most challenging portion of EDX study is motor unit action potential analysis, this topic is more extensively reviewed. The utility of the sensory NCS for identifying focal axon loss, the utility of the motor NCS for screening long nerve segments for focal demyelination and for determining lesion severity, and the utility of the needle EMG for confirming the NCS findings, better defining lesion localization, and identifying the temporal features (e.g., chronicity) and rate of progression of the lesion are also reviewed.

Clinical and neurophysiological recovery of ulnar nerve conduction block at the elbow.

INTRODUCTION/AIMS: An important mechanism of peripheral nerve motor and sensory dysfunction is conduction block (CB). However, recovery from mechanically induced CB has been rarely studied in humans. The aim of this study was to describe clinical, electrodiagnostic (EDx), and ultrasonographic (US) characteristics of CB recovery in ulnar neuropathy at the elbow (UNE). METHODS: We recruited a group of consecutive patients presenting to our EDx laboratory with UNE and >50% motor CB. Patients' histories were obtained and neurologic, EDx, and US examinations were repeated every 1-3 mo for at least 12 mo. RESULTS: We studied 10 patients (5 men), with a mean age of 63 y (range, 51-81 y). In all affected arms CB was localized to the retrocondylar groove. Following conservative management, myometrically measured index finger abduction improved from a median of 49% to 100% relative to the contralateral index finger, and ulnar nerve CB decreased from a median of 74% to 6%. Most of the improvement took place within 8 mo of symptom onset, and 6 mo after receiving treatment instructions. Mean motor nerve conduction velocity improved from 15 to 27 m/s in the most affected 2-cm ulnar nerve segment. DISCUSSION: The resolution of CB after typical chronic compression may take longer than after acute compression. This should be considered by clinicians when estimating prognosis for discussions with patients.

Exploring the role of biopsy-proven diabetic axonal neuropathy in outcomes of carpal tunnel release in diabetic and non-diabetic populations.

BACKGROUND: Carpal tunnel release outcomes in diabetic and non-diabetic patients are conflicting, possibly due to lack of differentiating patients with axonal neuropathy and those without axonal neuropathy. MATERIALS AND METHODS: Sixty-five diabetic and 106 non-diabetic patients who failed conservative treatment and then underwent carpal tunnel release from 2015 to 2022 were selected from a hand surgeon's patient database. Diagnosis was established with parameters established with the CTS-6 Evaluation Tool, and electrodiagnosis when indicated. Patient outcomes were evaluated using preoperative and postoperative Disabilities of Arm Shoulder and Hand (DASH), Brief Pain Inventory (BPI), Boston Carpal Tunnel Questionnaire, Numeric Pain Scale, and Wong-Baker Pain Scale. Postoperative evaluations were taken 6 months to a year post-surgery. Skin biopsies for nerve fiber density and morphology were taken from 50 diabetic patients. Another 50 were taken from non-diabetic patients with carpal tunnel syndrome and served as controls. Biopsy-proven axonal neuropathy was used as a confounding variable in the assessment of diabetic patients' recovery RESULTS: When comparing diabetics with biopsy-proven axonal neuropathy to diabetics without axonal neuropathy, the recovery outcomes are increasingly better for diabetics without neuropathy. Diabetics with biopsy-proven neuropathy have an improvement in recovery outcomes as well; however, not to the level of non-diabetics. CONCLUSION: Patients with increased scale scores or clinical suspicion for axonal neuropathy can be offered the option of undergoing a biopsy, and counseled about the risks for increased time to meet outcomes comparable to non-diabetics and diabetics without axonal neuropathy.

Correlation of Carpal Tunnel Syndrome 6 Score and Physical Exam Maneuvers With Electrodiagnostic Test Severity in Carpal Tunnel Syndrome: A Blinded Prospective Cohort Study.

PURPOSE: Although carpal tunnel syndrome (CTS) can be diagnosed clinically with the Carpal Tunnel Syndrome 6 (CTS-6) evaluation tool, the relationship between disease severity and CTS-6 score has not been elucidated. The purpose of our study was to determine the correlation of the CTS-6 score and other physical examination maneuvers with the carpal tunnel severity grade by electrodiagnostic testing (EDT). We hypothesized that the CTS-6 score, Durkan test, and Semmes Weinstein Monofilament Testing (SWMT) positively correlate with EDT severity. METHODS: We prospectively enrolled 105 consecutive patients who presented to the office with suspected CTS, excluding those with previous surgery, previous EDT from an outside facility, or concomitant neuropathy. Four fellowship-trained hand surgeons obtained the CTS-6 score, time to obtain a positive Durkan compression test, and SWMT of the thumb, index, and middle fingers. All patients were sent for EDT. Hand surgeons were blinded to the results of the EDT, and the electrodiagnosticians were blinded to the clinical data. We used the Bland criteria (0-6) to grade CTS severity on EDT. This grade was compared with the CTS-6 score, Durkan time, and SWMT results. RESULTS: Using Spearman correlation coefficients, we found a weakly positive correlation between a higher CTS-6 score and a higher severity grade on EDT. The mean CTS-6 score based on EDT grading were the following: (1) 14.8 (grade 0), (2) 16.0 (grade 1), (3) 14.8 (grade 2), (4) 16.7 (grade 3), (5) 18.7 (grade 4), (6) 18.3 (grade 5), and (7) 22.4 (grade 6). We also found a statistically significant association between the SWMT and a higher CTS-6 score as well as a higher severity grade on EDT. Durkan compression test did not appear to correlate with the EDT grade. CONCLUSIONS: The CTS-6 and SWMT show a positive correlation with EDT severity in CTS on the basis of the Bland criteria. The time to a positive Durkan test did not show any correlation. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic II.

Post COVID-19 Guillain-Barre syndrome presents as sensory dominant neuropathy with reversible conduction failure.

Guillain-Barré syndrome (GBS) has several clinical variants. The sensory presentations of GBS are atypical but well-recognized. We report a patient who presented with predominantly sensory symptoms associated with reversible conduction failure (RCF). RCF is a well-defined neurophysiological abnormality noted mainly in axonal GBS and may be misinterpreted as evidence of demyelination. A 25-year-old woman presented 2 weeks after a coronavirus 2019 infection with acute sensory symptoms, distal allodynia, mild weakness, and mild hyporeflexia in her upper limbs. A nerve conduction study (NCS) showed delayed motor distal latencies, and lumbar puncture confirmed cytoalbuminologic dissociation. After excluding other etiologies, she was diagnosed with GBS, treated with an IV immunoglobulin course, and showed remarkable recovery. Results of a repeat NCS were consistent with RCF and confirmed the presence of axonal GBS. Increased awareness of sensory GBS and RCF is expected to improve the diagnosis and management of atypical GBS presentations.

An electrophysiological prognostic diagnosis for facial palsy.

Two electrophysiological tests for facial palsy-electroneurography (ENoG) and nerve excitability test (NET)-were reviewed. ENoG has advantages over NET in that it reflects the percentage of degenerated facial nerve fibers and can provide an accurate prognosis. However, as disadvantages, ENoG requires large, expensive equipment, and such supramaximal electrical stimulation can be quite painful for patients. NET is less painful due to weak stimulation with just enough current to meet the threshold, and the required equipment is compact and inexpensive to procure. However, it is impossible to calculate the percentage of degenerated nerve fibers, and NET is inferior to ENoG in terms of accurate prognostic prediction for facial palsy. The appropriate timing for both ENoG and NET is 7 to 10 days after the onset. While ENoG has proven more popular than NET because of its accuracy for prognostic prediction, we should not predict the prognosis of facial palsy based solely on the results of electrophyisiolgical examinations; a comprehensive evaluation including the facial muscle grading system is essential.