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Background: Previous studies showed that vagus nerve stimulation (VNS) can improve cognitive function in patients with epilepsy, but there is still great controversy about the effect of VNS on cognitive function in patients with epilepsy. Objective: To investigate the effect of VNS on the cognitive function of epilepsy patients. Methods: Clinical trials published in PubMed, The Cochrane Library, and Embase before September 20, 2022, were comprehensively searched. Primary outcomes were overall cognitive performance, executive function, attention, memory; Secondary outcomes were seizure frequency, mood, and quality of life (QOL). Random effects were used to calculate the pooled outcome. Results: Twenty clinical trials were included. There was no significant improvement in overall cognitive performance in patients with epilepsy after VNS treatment (SMD = 0.07; 95% CI: -0.12 to 0.26; I2 = 0.00%) compared to pre-treatment. Compared to pre-treatment, there was no significant difference in executive function (SMD = -0.50; 95% CI: -1.50 to 0.50; p = 0.32), attention (SMD = -0.17; 95% CI: -0.43 to 0.09; p = 0.21) and memory (SMD = 0.64; 95% CI: -0.11 to 1.39; p = 0.09), but there were significant differences in seizure frequency, mood, and quality of life in patients with epilepsy after VNS. Conclusion: This meta-analysis did not establish that VNS can significantly improve cognitive function in patients with epilepsy, but it shows that VNS can significantly improve the seizure frequency, mood and quality of life of patients with epilepsy. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier: CRD42023384059.
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OBJECTIVES: The effectiveness of deep brain stimulation (DBS) in treating vocal tremors is currently a subject of debate. To assess the efficacy of DBS therapy in adults with vocal tremors (VT), we analyzed its impact on voice tremor severity, voice-related quality of life, fundamental frequency, voice intensity, and emotional state. METHODS: We conducted a systematic review with meta-analysis to investigate the impact of DBS therapy on voice tremor severity, voice-related quality of life, fundamental frequency, voice intensity, and emotional state in adults with vocal tremors (PROSPERO/CRD42023420272). The PubMed, Embase, Cochrane Library, Cochrane Central Register of Controlled Trials databases were searched up to September 20, 2022. Primary outcome measures included voice tremor severity and voice-related quality of life (V-RQOL), while fundamental frequency (F0) and voice intensity, along with emotional state, were selected as secondary outcome indicators. We employed the Cochrane Collaboration's tool for assessing bias risk in randomized trials. Meta-analysis (standardized difference of means and weighted mean differences) and heterogeneity analysis (I2) were performed. RESULTS: Our search identified 1186 studies, of which nine studies involving 61 patients met the inclusion criteria. The severity of voice tremor (SMD = -1.08; 95% CI: -1.80 to 0.35; P = 0.02) and V-RQOL (SMD = -1.39; 95% CI: -2.68 to -0.09; P = 0.04) in patients with vocal tremor significantly improved after DBS "on". Subgroup analyses revealed that the stimulation site may contribute to high heterogeneity. Specifically, Vim DBS showed significant improvement in voice tremor severity (SMD = -0.97; 95% CI: -1.84 to -0.09; I2 = 51.01%), while STN DBS did not demonstrate a clear benefit in addressing vocal tremor. There was no significant difference between DBS "on" and DBS "off" in terms of F0, voice intensity, or emotional status. CONCLUSION: DBS therapy is effective in enhancing voice quality and voice-related quality of life in patients with vocal tremors. Notably, Vim DBS demonstrates a significant improvement in voice tremor severity, particularly in VT patients with ET and SD.
RESUMO
OBJECTIVE: This study aimed to investigate the effects of different types of masks on acoustic, aerodynamic, and formant parameters in healthy people. METHODS: Our study involved 30 healthy participants, 15 of each gender, aged 20-40 years. The tests were conducted under four conditions: without a mask, after wearing a surgical mask, after wearing a head-mounted N95 mask, and after wearing an ear-mounted N95 mask. Voice recording was done with the mask on. The acoustic parameters include mean fundamental frequency (F0), mean intensity, percentage of jitter (local), percentage of shimmer (local), mean noise to harmonic ratio (NHR), aerodynamic parameter, maximum phonation time (MPT), and formant parameters (/a/, /i/, /u/ three vowels F1, F2). RESULTS: The main effect of mask type was significant in MPT, mean F0, mean HNR, /a/F1, /a/F2, /i/F2. However, the effect sizes and power in /a/F2, /i/F2 were low. MPT, mean F0 and mean HNR significantly increased and /a/F1 significantly decreased after wearing the head-mounted n95 mask. The mean F0 and mean HNR increased significantly after wearing the ear-mounted n95 mask. No significant changes were observed in parameters after wearing the surgical mask in this study. When the statistics are performed separately for males and females, the results obtained are similar to those previously obtained for unspecified males and females. CONCLUSION: After wearing the surgical mask, this study found insignificant changes in mean F0, jitter (local), shimmer (local), mean NHR, mean intensity, MPT, and the vowels F1 and F2. This may be due to the looser design of the surgical mask and the relatively small attenuation of sound. N95 masks have a greater effect on vocalization than surgical masks and may cause changes in F0 and HNR after wearing an N95 mask. In the present study, no significant changes in jitter and shimmer were observed after wearing the mask. In addition, there was a significant reduction in /a/F1 after wearing the N95 headgear mask may owing to its high restriction of jaw mobility. In future studies, the change in jaw movement amplitude after wearing the mouthpiece can be added to investigate.
