Neurophysiologie Clinique/Clinical Neurophysiology最新文献

Objectives

To examine postnatal functional status of the brainstem auditory pathway in late preterm infants and detect any postnatal auditory abnormality.

Methods

Thirty preterm infants born at 33–36 weeks gestation were studied three months after term. None had major perinatal and postnatal complications to minimize confounding effects. Brainstem auditory evoked responses were recorded with 21–91/s clicks.

Results

Compared with postnatal age-matched normal term infants, the late preterm infants did not manifest any major abnormalities in brainstem auditory evoked responses at conventionally used 21/s clicks. At higher click rates, however, the late preterm infants manifested a moderate prolongation in BAER wave V latency. All interpeak intervals tended to be prolonged at higher click rates. The I-V interval was significantly prolonged at 51/s and particularly at 91/s clicks. Both the I-III and III-V intervals were significantly prolonged at 91/s. The late preterm infants also manifested reduced amplitudes of BAER waves III and V at most click rates.

Conclusion

The central components of the brainstem auditory evoked responses were abnormal at higher click rates three months after term in the late preterm infants. Postnatal brainstem auditory function is suboptimal in late preterm infants without major complications. This suboptimal brainstem auditory function may not be clearly shown at term or an earlier stage, but can be shown later. Late preterm infants, although they may not have major complications, should be followed for later auditory development, providing valuable information for improving postnatal care.

Objectives

To synthesise the literature on the efficacy of primary motor cortex anodal transcranial direct current stimulation (M1-a-tDCS), as a standalone or priming technique, for pain reduction in people with knee osteoarthritis (KOA).

Methods

The systematic literature search was conducted in MEDLINE, CINAHL, Embase and CENTRAL according to PRISMA statement.

Results

Fourteen studies involving 740 people with KOA were included. In the meta-analysis, six studies compared a-tDCS alone with sham stimulation, and five studies compared a-tDCS combined with other methods with sham stimulation. We found positive effect of a-tDCS alone on pain in KOA (standard mean difference (SMD) −0.52; 95% CI, −0.78 to −0.25; P=0.001; I2 = 69%). Further, a-tDCS with other treatments showed positive effect (SMD −1.23; 95% CI, −1.59 to −0.88; P<0.001; I2 = 48%) on pain in people with KOA. This evidence showed low certainty due to a high risk of bias and imprecision.

Discussion and Conclusion

A-tDCS could be considered as standalone and an adjunct treatment for pain reduction in people with KOA. Future randomised studies should address quality issues, including small sample size, to enhance the overall certainty of the findings.

Significance

A-tDCS can be used as a standalone and adjunct treatment for KOA.

Study registration

PROSPERO number CRD42021255114

Objective

Transcranial direct current stimulation (tDCS) has demonstrated its efficacy in alleviating pain among individuals with musculoskeletal disorders. This review focuses on the application of tDCS as a therapeutic intervention for managing knee osteoarthritis (OA), a prevalent musculoskeletal condition. The primary objective is to assess the effectiveness of tDCS(add-on tDCS and /or stand-alone tDCS), whether as an add-on to existing treatments or as a standalone therapy, in reducing pain and enhancing functional capacity in patients with knee OA.

Methods

A comprehensive search was conducted across multiple databases, including PubMed, Science Direct, OVID, MEDLINE, CINAHL, EMBASE, ProQuest, and Google Scholar, and Web of Science. The search terms employed were "Transcranial direct current stimulation" or "tDCS" in combination with "Osteoarthritis" or "OA" and "knee." After eliminating duplicates and studies that did not meet the inclusion criteria, a total of 14 relevant articles were identified for review.

Results

Among the included studies, twelve reported statistically significant improvements in pain levels when comparing the active tDCS group to the sham tDCS group. Only two studies reported no significant difference in pain intensity between the active tDCS and sham tDCS groups. Findings regarding functional abilities were diverse, with some studies demonstrating a significant enhancement in functional outcomes in the active tDCS group, while others observed no statistically significant differences.

Conclusion

The results of this review suggest that tDCS holds promise as a pain management intervention for individuals with knee OA. Notably, anodal tDCS applied over the primary motor cortex (M1) appears to be particularly effective in alleviating pain in patients with knee OA. However, the impact of tDCS on functional performance appears to be limited.

Objective

The present study investigated the relationship between three genetic polymorphisms of OPRM1 (rs1799971 - A118G and rs1799972 - C17T) and BDNF (rs6265 - C196T) and EEG-measured brain oscillations in Knee Osteoarthritis (KOA) patients.

Materials and Methods

We performed a cross-sectional analysis of a cohort study (DEFINE cohort), KOA arm, with 66 patients, considering demographic (age, sex, and education), clinical (pain intensity and duration), OPRM1 (rs1799971 - A118G and rs1799972 - C17T) and BDNF (rs6265 - C196T) genotypes, and electrophysiological measures. Brain oscillations relative power from Delta, Theta, Alpha, Low Alpha, High Alpha, Beta, Low Beta and High Beta oscillations were measured during resting state EEG. Multivariate regression models were used to explore the main brain oscillation predictors of the three genetic polymorphisms.

Results

Our findings demonstrate that Theta and Low Beta oscillations are associated with the variant allele of OPRM1-rs1799971 (A118G) on left frontal and left central regions, respectively, while Alpha brain oscillation is associated with variant genotypes (CT/TT) of BDNF-rs6265 on frontal (decrease of oscillation power) and left central (increase of oscillation power) regions. No significant model was found for OPRM1-rs1799972 (C17T) in addition to the inclusion of pain intensity as a significant predictor of this last model.

Conclusion

One potential interpretation for these findings is that polymorphisms of OPRM1 – that is involved with endogenous pain control - lead to increased compensatory oscillatory mechanisms, characterized by increased theta oscillations. Along the same line, polymorphisms of the BDNF lead to decreased alpha oscillations in the frontal area, likely also reflecting the disruption of resting states to also compensate for the increased injury associated with knee OA. It is possible that these polymorphisms require additional brain adaption to the knee OA related injury.

Objective

Preoperative non-invasive mapping of motor function with navigated transcranial magnetic stimulation (nTMS) has become a widely used diagnostic procedure. Determination of the patient-individual resting motor threshold (rMT) is of great importance to achieve reliable results when conducting nTMS motor mapping. Factors which contribute to differences in rMT of brain tumor patients have not been fully investigated.

Methods

We included adult patients with all types of de novo and recurrent intracranial lesions, suspicious for intra-axial brain tumors. The outcome measure was the rMT of the upper extremity, defined as the stimulation intensity eliciting motor evoked potentials with amplitudes greater than 50µV in 50 % of applied stimulations.

Results

Eighty nTMS examinations in 75 patients (37.5 % female) aged 57.9 ± 14.9 years were evaluated. In non-parametric testing, rMT values were higher in patients with upper extremity paresis (p = 0.024) and lower in patients with high grade gliomas (HGG) (p = 0.001). rMT inversely correlated with patient age (r_s=-0.28, p = 0.013) and edema volume (r_s=-0.28, p = 0.012) In regression analysis, infiltration of the precentral gyrus (p<0.001) increased rMT values. Values of rMT were reduced in high grade gliomas (p<0.001), in patients taking Levetiracetam (p = 0.019) and if perilesional edema infiltrated motor eloquent brain (p<0.001). Subgroup analyses of glioma patients revealed similar results. Values of rMT did not differ between hand and forearm muscles.

Conclusion

Most factors confounding rMT in our study were specific to the lesion. These factors contributed to the variability in cortical excitability and must be considered in clinical work with nTMS to achieve reliable results with nTMS motor mapping.

We utilized computational analysis to investigate the impact of skull defects and skull implants on the TMS-induced EF. Our findings revealed a noteworthy alteration in the induced EF when acute skull defects were present. When high-conductivity titanium plates were used, we observed a pronounced increase in the peak EF, accompanied by a shift in the induced EF from the center towards both ends of the implant. These findings underscore the importance of carefully considering skull defects and implant materials during TMS.

Objective

This study aims to evaluate the feasibility of substituting electrochemical skin conductance measurement using SUDOSCAN for sudomotor function testing in the Composite Autonomic Scoring Scale (CASS) and to correlate the results with the Composite Autonomic Symptom Scale 31 (COMPASS 31) among patients with type 2 diabetes mellitus (T2DM).

Methods

Fifty patients with T2DM underwent cardiovascular autonomic function testing and the SUDOSCAN test and completed the COMPASS 31 questionnaire. We developed a SUDOSCAN-based sudomotor subscore as a substitute for the original sudomotor subscore (based on the quantitative sudomotor axon reflex test [QSART]). The modified CASS score (SUDOSCAN-based sudomotor subscore combined with the adrenergic and cardiovagal subscores) and the original CASS score without suomotor assessment (sum of the adrenergic and cardiovagal subscores) were obtained according to the results of the cardiovascular autonomic function and SUDOSCAN tests.

Results

The total COMPASS 31 score was significantly correlated with the modified CASS score (p = 0.019 and 0.037 for the raw and weighted scores, respectively) but not with the CASS score without sudomotor assessment. After adding the SUDOSCAN-based sudomotor subscore, the number of patients identified as having diabetic autonomic neuropathy (DAN) increased from 24 (48 %, based on the CASS score without sudomotor assessment) to 35 (70 %, based on the modified CASS score). The modified CASS score enhances the accuracy of assessing autonomic function and improves the diagnosis of diabetic autonomic neuropathy (DAN) among patients with T2DM. In medical settings where QSART is not accessible, SUDOSCAN testing offers a practical and efficient alternative.

Objectives

Encephalopathy is a severe pathological process induced by multiple factors, which is typically associated with electroencephalogram (EEG) abnormalities. Early diagnosis, management, and treatment improve the patient's prognosis. Psychotropic treatments are a risk for drug-induced encephalopathies. In this study, the prevalence of encephalopathies in a psychiatric hospital has been studied for 5 years (2012 to 2016) using 5217 EEG records.

Methods

EEGs were performed i) systematically on patient admission, ii) in response to inexplicable modifications of consciousness or behavior, or when metabolic anomalies occurred, and iii) to perform therapeutic monitoring in outpatient consultations. When encephalopathy was suspected, the clinical data (age, sex and concomitant treatment) and biological data (plasma levels of medications) were collected.

Results

Encephalopathy was suspected in 189 patients. Following EEG examination, and monitoring of clinical course, encephalopathy was subsequently determined to be highly probable for 52 patients, (giving a prevalence of 1% per year), and low suspicion of encephalopathy in the other 137 patients. The suspicion of encephalopathy was made on both clinical (n=28) and non-clinical (n=24) signs. Involved drugs were mainly valproic acid (n=14), lithium (n=11) and clozapine (n=11) in the highly probable encephalopathy group.

Conclusions

Our study demonstrates the importance of EEG in the diagnosis and monitoring of encephalopathies in a psychiatric hospital. Clinical symptoms of encephalopathies are polymorphic and sometimes atypical. This diagnosis is underestimated in a context where behavior or consciousness disorders are generally not attributed to psychotropic drugs used in psychiatry.

Objective

Intermittent theta burst stimulation (iTBS) is based on the phase-amplitude coupling (PAC) pattern. We aimed to investigate the effect of iTBS on PAC in resting electroencephalography (EEG), which may provide insight into the underlying mechanism.

Methods

Twenty-one healthy volunteers were recruited and received both active and sham neuroimaging-guided iTBS on two separate days, which was precisely delivered to the right superior temporal gyrus. On each experimental day, resting EEG was recorded before and after stimulation for each participant. PACs across electrodes and frequency bands were calculated and compared to investigate the effect of iTBS.

Results

Theta (4–6 Hz) -low gamma (45–55 Hz) PAC over the stimulation site had a significant interaction effect, which increased after the active iTBS but did not differ after the sham iTBS. No significant interaction effect occurred in other cross-frequency couplings such as delta-low gamma, alpha-low gamma, delta-high gamma, theta-high gamma, or alpha-high gamma PAC in the region of interest.

Conclusion

iTBS selectively modulated theta-low gamma PAC at the stimulation area, which exhibited both region- and frequency- specificity. This suggests that PAC may be a bridge connecting external neuromodulation to internal neuroplasticity.