I. Zay Melville , Kyla Yamsuan , Helen Wu , Peter R. Thorne , Kei Kobayashi , Rachael L. Taylor
{"title":"Do measures of gain asymmetry and catch-up saccades improve video head impulse test agreement with caloric results?","authors":"I. Zay Melville , Kyla Yamsuan , Helen Wu , Peter R. Thorne , Kei Kobayashi , Rachael L. Taylor","doi":"10.1016/j.cnp.2024.07.001","DOIUrl":"10.1016/j.cnp.2024.07.001","url":null,"abstract":"<div><h3>Objective</h3><p>To investigate the relative sensitivity and agreement of caloric testing and video head impulse test (vHIT) across four groups of vestibular disorders.</p></div><div><h3>Methods</h3><p>Caloric and vHIT results of 118 patients with either Ménière’s disease, vestibular neuritis/labyrinthitis, vestibular migraine, or vestibular schwannoma were retrospectively analyzed. vHIT gain, gain asymmetry, and catch-up-saccades (≥100°/sec) were compared with reference limits of 91 controls.</p></div><div><h3>Results</h3><p>Abnormal caloric results and vHIT gain were recorded in 57.6 % and 33.1 % of patients, respectively. Consideration of all three measures increased vHIT sensitivity to 43.2 %, and concordance with caloric results improved from 66.1 % to 70.3 %. A significant interaction effect confirmed the relationship between tests depended on the diagnosis (p = 0.013). Vestibular migraine and vestibular neuritis/labyrinthitis produced similar results on both tests, usually normal and abnormal respectively. Vestibular schwannoma produced more caloric abnormalities than vHIT gain but not compared with catch-up-saccades and gain asymmetry; Ménière’s disease produced more caloric abnormalities than all vHIT measures. When vHIT was normal (all measures), a 37 % canal paresis was 90 % specific for Ménière’s disease.</p></div><div><h3>Conclusions</h3><p>Rates of vHIT catch-up-saccades and gain asymmetry can improve sensitivity and concordance with caloric testing, but this is disease-dependent.</p></div><div><h3>Significance</h3><p>vHIT outcome measures are complementary to the caloric test and each other.</p></div>","PeriodicalId":45697,"journal":{"name":"Clinical Neurophysiology Practice","volume":"9 ","pages":"Pages 217-226"},"PeriodicalIF":2.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2467981X24000209/pdfft?md5=7818b0a50eef5b4bed91e0a41abd8b17&pid=1-s2.0-S2467981X24000209-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141710606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ø. Dunker , T.S. Szczepanski , H.O.P. Do , P. Omland , M.U. Lie , T. Sand , J.F. Jabre , K.B. Nilsen
{"title":"Harnessing historical data to derive reference limits – A comparison of e-norms to traditionally derived reference limits","authors":"Ø. Dunker , T.S. Szczepanski , H.O.P. Do , P. Omland , M.U. Lie , T. Sand , J.F. Jabre , K.B. Nilsen","doi":"10.1016/j.cnp.2024.04.001","DOIUrl":"10.1016/j.cnp.2024.04.001","url":null,"abstract":"<div><h3>Objective</h3><p>Nerve conduction studies (NCS) require valid reference limits for meaningful interpretation. We aimed to further develop the extrapolated norms (e-norms) method for obtaining NCS reference limits from historical laboratory datasets for children and adults, and to validate it against traditionally derived reference limits.</p></div><div><h3>Methods</h3><p>We compared reference limits obtained by applying a further developed e-norms with reference limits from healthy controls for the age strata’s 9–18, 20–44 and 45–60 years old. The control data consisted of 65 healthy children and 578 healthy adults, matched with 1294 and 5628 patients respectively. Five commonly investigated nerves were chosen: The tibial and peroneal motor nerves (amplitudes, conduction velocities, F-waves), and the sural, superficial peroneal and medial plantar sensory nerves (amplitudes, conduction velocities). The datasets were matched by hospital to ensure identical equipment and protocols. The e-norms method was adapted, and reference limit calculation using both ±2 SD (original method) and ±2.5 SD (to compensate for predicted underestimation of population SD by the e-norms method) was compared to control data using ±2 SD. Percentage agreement between e-norms and the traditional method was calculated.</p></div><div><h3>Results</h3><p>On average, the e-norms method (mean ±2 SD) produced slightly stricter reference limits compared to the traditional method. Increasing the e-norms range to mean ±2.5 SD improved the results in children while slightly overcorrecting in the adult group. The average agreement between the two methods was 95 % (±2 SD) and 96 % (±2.5 SD).</p></div><div><h3>Conclusions</h3><p>The e-norms method yielded slightly stricter reference limits overall than ones obtained through traditional methods; However, much of the difference can be attributed to a few outlying plots where the raters found it difficult to apply e-norms correctly.<!--> <!-->The two methods disagreed on classification of 4–5% of cases. Our e-norms software is suited to analyze large amounts of raw NCS data; it should further reduce bias and facilitate more accurate ratings.</p></div><div><h3>Significance</h3><p>With small adaptations, the e-norms method adequately replicates traditionally derived reference limits, and is a viable method to produce reference limits from historical datasets.</p></div>","PeriodicalId":45697,"journal":{"name":"Clinical Neurophysiology Practice","volume":"9 ","pages":"Pages 168-175"},"PeriodicalIF":1.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2467981X24000155/pdfft?md5=64f25142bfd766fa5e5d681037d332ee&pid=1-s2.0-S2467981X24000155-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140787470","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Diagnosis and differential diagnosis of MND/ALS: IFCN handbook chapter","authors":"Mamede de Carvalho , Michael Swash","doi":"10.1016/j.cnp.2023.12.003","DOIUrl":"10.1016/j.cnp.2023.12.003","url":null,"abstract":"<div><p>Accurate and rapid diagnosis of amyotrophic lateral sclerosis (ALS) is essential in order to provide accurate information for patient and family, to avoid time-consuming investigations and to permit an appropriate management plan. ALS is variable regarding presentation, disease progression, genetic profile and patient reaction to the diagnosis. It is obviously important to exclude treatable conditions but, in most patients, for experienced neurologists the diagnosis is clear-cut, depending on the presence of progressive upper and lower motor neuron signs. Patients with signs of restricted lower motor neuron (LMN) or upper motor neuron (UMN) dysfunction may present diagnostic difficulty, but electromyography (EMG) is often a determinant diagnostic test since it may exclude other disorders. Transcranial magnetic stimulation may aid detection of UMN dysfunction, and brain and spinal cord MRI, ultrasound and blood neurofilament measurements, have begun to have clinical impact, although none are themselves diagnostic tests. Several sets of diagnostic criteria have been proposed in the past; all rely on clinical LMN and UMN signs in different anatomic territories, EMG changes, exclusion of other disorders, and disease progression, in particular evidence of spreading to other anatomic territories. Fasciculations are a characteristic clinical feature and increased importance is now attached to fasciculation potentials detected by EMG, when associated with classical signs of denervation and reinnervation. The Gold Coast diagnostic criteria rely on the presence of UMN and LMN signs in one (or more) anatomic territory, or LMN signs in two (or more) anatomic territories, recognizing the fundamental clinical requirements of disease progression and exclusion of other diseases. Recent studies confirm a high sensitivity without loss of specificity using these Gold Coast criteria. In considering the diagnosis of ALS a critical question for future understanding is whether ALS should be considered a syndrome or a specific clinico-pathologic entity; this can only be addressed in the light of more complete knowledge.</p></div>","PeriodicalId":45697,"journal":{"name":"Clinical Neurophysiology Practice","volume":"9 ","pages":"Pages 27-38"},"PeriodicalIF":1.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2467981X23000355/pdfft?md5=a5fa4ccc67823182f5565a3f5a377e49&pid=1-s2.0-S2467981X23000355-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139019674","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"REM parasomnias: Straddling the sleep-wake line","authors":"Jayant N. Acharya, Vinita J. Acharya","doi":"10.1016/j.cnp.2024.01.002","DOIUrl":"10.1016/j.cnp.2024.01.002","url":null,"abstract":"","PeriodicalId":45697,"journal":{"name":"Clinical Neurophysiology Practice","volume":"9 ","pages":"Pages 51-52"},"PeriodicalIF":1.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2467981X24000039/pdfft?md5=90c8ff173712075f56fbe8fb9f775611&pid=1-s2.0-S2467981X24000039-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139456916","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Daniel San-juan , Rafael Diaz-Martinez , Victor Alcocer-Barradas , Luis Alberto Ortega-Porcayo , Marcela Amparo Osuna-Zazueta , Maria Fernanda Tejada-Pineda
{"title":"Spinal lumbar multimodal neurophysiological monitoring in a patient with deep brain Stimulator: A case report","authors":"Daniel San-juan , Rafael Diaz-Martinez , Victor Alcocer-Barradas , Luis Alberto Ortega-Porcayo , Marcela Amparo Osuna-Zazueta , Maria Fernanda Tejada-Pineda","doi":"10.1016/j.cnp.2024.10.003","DOIUrl":"10.1016/j.cnp.2024.10.003","url":null,"abstract":"<div><div>Intraoperative neurophysiological monitoring (IONM) is a highly valuable tool in spinal surgery. It allows for real-time evaluation of nervous system function and alerts the surgeon to any warning signs. Among the various techniques used are motor evoked potentials (MEPs) through transcranial electrical stimulation, which involve applying an electrical stimulus to the scalp in the primary motor cortex region and recording it in the corresponding muscles of the corticospinal tract. There are relative contraindications for this technique, such as in patients who have an implantable device. There is no consensus on how to perform this technique in patients with a deep brain stimulator.</div><div>We present the case of a 61-year-old patient with Parkinson’s disease and a deep brain stimulator (DBS), and who underwent spinal surgery for lumbar discopathy. IONM was performed during the procedure using MEPs, necessitating the deactivation of the DBS to protect its function. Upon completion of the surgical procedure, the device was reactivated, confirming its proper function. We demonstrate that this technique can be safe for these patients, weighing the potential risks and benefits. However, it will be necessary to develop specific guidelines for performing these techniques in the future.</div></div>","PeriodicalId":45697,"journal":{"name":"Clinical Neurophysiology Practice","volume":"9 ","pages":"Pages 261-265"},"PeriodicalIF":2.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142571621","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chiara Abagnale , Gabriele Sebastianelli , Francesco Casillo , Antonio Di Renzo , Vincenzo Parisi , Ettore Cioffi , Mariano Serrao , Jean Schoenen , Gianluca Coppola , Cherubino Di Lorenzo
{"title":"A 1-month ketogenic diet in patients with migraine gives a clinical beneficial effect associated with increased latency of somatosensory thalamo-cortical activity","authors":"Chiara Abagnale , Gabriele Sebastianelli , Francesco Casillo , Antonio Di Renzo , Vincenzo Parisi , Ettore Cioffi , Mariano Serrao , Jean Schoenen , Gianluca Coppola , Cherubino Di Lorenzo","doi":"10.1016/j.cnp.2024.11.002","DOIUrl":"10.1016/j.cnp.2024.11.002","url":null,"abstract":"<div><h3>Objective</h3><div>Since the habituation deficit of evoked potentials could be related to abnormal thalamocortical drive, we searched for a modulatory effect of ketogenic diet (KD) on somatosensory-evoked thalamo-cortical activity. KD is effective in preventing migraine. Previous studies showed that KD normalises habituation of somatosensory and visual cortical evoked responses in parallel with a decrease in of migraine attack frequency.</div></div><div><h3>Methods</h3><div>We electrically stimulated the median nerve at the wrist to record somatosensory high-frequency oscillations (HFOs) in twenty patients with episodic migraine with and without aura before and after one month of normo- (n = 9) or hypocaloric KD (n = 11). For pre-synaptic thalamocortical and post-synaptic cortical HFOs, we measured the latency of the negative oscillatory maximum, the intra-burst frequency, the number of negative peaks, and the maximum peak-to-peak amplitude.</div></div><div><h3>Results</h3><div>In the total group of patients, the one-month KD significantly increased the latency of the negative oscillatory maximum in pre-synaptic, i.e. thalamocortical activity (t = 2.70, p = 0.015) and in post-synaptic HFOs, i.e. cortical activity (t = 3.08, p = 0.006). This effect could be attributed to hypo-caloric KD, as it was not found after normo-caloric KD. Other HFO parameters, such as amplitude, duration, or number of oscillations, were not affected.</div></div><div><h3>Conclusions</h3><div>A 1-month hypo-caloric KD is able to delay the propagation of neuronal activity through the thalamo-cortical network. This effect does not seem to be correlated with the therapeutic efficacy of KD, but rather to low-calorie intake.</div></div><div><h3>Significance</h3><div>Our results imply that consuming a restricted amount of calories could alter the balance between central excitation and inhibition in migraine.</div></div>","PeriodicalId":45697,"journal":{"name":"Clinical Neurophysiology Practice","volume":"9 ","pages":"Pages 292-298"},"PeriodicalIF":2.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142698312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Stephan Neidhart , Oona Kohnen , Lennart Stieglitz , Lukas Imbach
{"title":"Directional deep brain stimulation of the centromedian thalamic nucleus reduces DBS-induced ataxia and dysarthria in Lennox-Gastaut Syndrome: A single case study","authors":"Stephan Neidhart , Oona Kohnen , Lennart Stieglitz , Lukas Imbach","doi":"10.1016/j.cnp.2024.08.001","DOIUrl":"10.1016/j.cnp.2024.08.001","url":null,"abstract":"<div><h3>Background</h3><p>We present a case of a 46-year-old man with Lennox-Gastaut syndrome and drug-resistant epilepsy. An adjunctive neurostimulation therapy strategy was implemented involving bilateral deep brain stimulation (DBS) of the centromedian thalamic nucleus (CMT).</p></div><div><h3>Methods</h3><p>Robotically assisted implantation of bilateral DBS directional lead system with 8 contacts in the CMT was performed. The clinical course was assessed in repeated in-patient follow-ups.</p></div><div><h3>Results</h3><p>Initial DBS stimulation resulted in progressive ataxia and dysarthria significantly beyond the level seen before surgery. Deactivation of DBS coincided with improvement of dysarthria. A DBS stimulation paradigm with reduction of lateral and superior stimulation resulted in improvement and eventually complete resolution of the stimulation side effect.</p></div><div><h3>Discussion</h3><p>This case suggests that stimulation-induced dysarthria in DBS can be improved by targeted reduction of lateral and/or superior thalamic stimulation. When dysarthria and ataxia occur during DBS, directed stimulation to medial thalamic structures and more inferior electrode contacts offers a promising strategy to reduce side effects while maintaining positive effects.</p></div>","PeriodicalId":45697,"journal":{"name":"Clinical Neurophysiology Practice","volume":"9 ","pages":"Pages 233-235"},"PeriodicalIF":2.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2467981X24000222/pdfft?md5=be5e66cca745f2972659627bfc20c150&pid=1-s2.0-S2467981X24000222-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142097607","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Visualization of radial nerve activity at the upper arm using magnetoneurography","authors":"Takeyasu Toyama , Muneharu Ando , Masaaki Paku , Shinji Sato , Yusuke Yamamoto , Shinichirou Taniguchi , Nobuo Kohara , Takanori Saito","doi":"10.1016/j.cnp.2024.11.001","DOIUrl":"10.1016/j.cnp.2024.11.001","url":null,"abstract":"<div><h3>Objective</h3><div>To evaluate the function of the radial nerve in the upper arm using Magnetoneurography (MNG).</div></div><div><h3>Methods</h3><div>Eight asymptomatic male volunteers (age 25–63 years) and one 67-year-old female patient with radial nerve palsy were included. The radial nerve was electrically stimulated in the right wrist, and the evoked magnetic field was recorded using a 132-channel bio-magnetometer system with a superconducting quantum interference device positioned below the upper arm. The measurements were divided into distal and proximal sessions because of the extensive range of the nerve.</div></div><div><h3>Results</h3><div>MNG recorded the radial nerve’s evoked magnetic field in all cases, and the neural activity of the radial nerve at the upper arm was visualized using reconstructed currents. The mean conduction velocity calculated from the peak latency of the inward currents was 43.9 m/s for distal measurements and 57.9 m/s for proximal measurements. A 67-year-old female patient with radial nerve palsy had a disappearance of the reconstructed inward current and conduction disturbance of the axonal current, facilitating the identification of the lesion site.</div></div><div><h3>Conclusions</h3><div>MNG allowed visualization of the radial nerve activity in the upper arm and facilitated the identification of the lesion site in a patient with radial nerve palsy.</div></div><div><h3>Significance</h3><div>This method could be a useful diagnostic tool for patients with radial nerve palsy.</div></div>","PeriodicalId":45697,"journal":{"name":"Clinical Neurophysiology Practice","volume":"9 ","pages":"Pages 283-291"},"PeriodicalIF":2.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142698310","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Marie Laure Inghilleri , Sandrine Alonso , Hélène Moron , Hector Ruiz , Sophie Bastide , Sarah Coudray
{"title":"The value of ultrasound-guidance of nerves and muscles for patient tolerance and parameters electrodiagnostic studies","authors":"Marie Laure Inghilleri , Sandrine Alonso , Hélène Moron , Hector Ruiz , Sophie Bastide , Sarah Coudray","doi":"10.1016/j.cnp.2024.01.003","DOIUrl":"10.1016/j.cnp.2024.01.003","url":null,"abstract":"<div><h3>Objective</h3><p>To assess impact of ultrasound guidance (USG) on patient’s perception of nerve conduction studies (NCS).</p></div><div><h3>Methods</h3><p>In this single-center, randomized, sham-controlled, parallel, single-blind trial, we evaluated ultrasound (US) in identifying NCS stimulation site. Consecutive adults (18–80 old) without neuropathy referred for NCS were electronically randomized 1:1 to USG or Sham US. The primary outcome was sensory supramaximal intensity (SSMI) for each site/nerve; motor supramaximal intensity (MSMI), amplitudes, number of non-routine muscle punctured, Visual Analogue Scale (VAS), satisfaction were secondary outcomes.</p></div><div><h3>Results</h3><p>290 participants were randomized, with 145 in the USG and 144 Sham US groups, respectively. No difference in SSMI, CMAP or SNAP, VAS, satisfaction was recorded. With USG, the median at the elbow and fibular MMSI were lower (p = 0.04; p = 0.02). With normal NCS or overweight and obese subgroups patients had lower median SSMI (p = 0.05/ p = 0.02), higher median and sural SNAP with normal NCS (p = 0.04; p = 0.007) and the sural SNAP for the expert US subgroup (p = 0.02).</p></div><div><h3>Conclusions</h3><p>USG is useful for nerves, that are anatomically variable or in obesity. The sural SNAP gain with US in the normal NCS subgroup could facilitate routine NCS.</p></div><div><h3>Significance</h3><p>In standard NCS the USG does not modify the patient’s tolerance.</p><p><strong>Trial Registration:</strong> clinicaltrials.gov (NCT03868189).</p></div>","PeriodicalId":45697,"journal":{"name":"Clinical Neurophysiology Practice","volume":"9 ","pages":"Pages 78-84"},"PeriodicalIF":1.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2467981X24000064/pdfft?md5=b429328969813cf5ba4ede5768daa0d1&pid=1-s2.0-S2467981X24000064-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139637403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}