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《Clinical neurophysiology》2021,132(10):2357-2364
ObjectivesTo investigate the subcortical somatosensory evoked potentials (SEPs) to electrical stimulation of either muscle or cutaneous afferents.MethodsSEPs were recorded in 6 patients suffering from Parkinson’s disease (PD) who underwent electrode implantation in the pedunculopontine (PPTg) nucleus area. We compared SEPs recorded from the scalp and from the intracranial electrode contacts to electrical stimuli applied to: 1) median nerve at the wrist, 2) abductor pollicis brevis motor point, and 3) distal phalanx of the thumb. Also the high-frequency oscillations (HFOs) were analysed.ResultsAfter median nerve and pure cutaneous (distant phalanx of the thumb) stimulation, a P1-N1 complex was recorded by the intracranial lead, while the scalp electrodes recorded the short-latency far-field responses (P14 and N18). On the contrary, motor point stimulation did not evoke any low-frequency component in the PPTg traces, nor the N18 potential on the scalp. HFOs were recorded to stimulation of all modalities by the PPTg electrode contacts.ConclusionsStimulus processing within the cuneate nucleus depends on modality, since only the cutaneous input activates the complex intranuclear network possibly generating the scalp N18 potential.SignificanceOur results shed light on the subcortical processing of the somatosensory input of different modalities.  相似文献   
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ObjectiveSpinal cord stimulation (SCS) is an effective treatment in failed back surgery syndrome (FBSS). We studied the effect of preimplantation opioid use on SCS outcome and the effect of SCS on opioid use during a two-year follow-up period.Materials and methodsThe study cohort included 211 consecutive FBSS patients who underwent an SCS trial from January 1997 to March 2014. Participants were divided into groups, which were as follows: 1) SCS trial only (n = 47), 2) successful SCS (implanted and in use throughout the two-year follow-up period, n = 131), and 3) unsuccessful SCS (implanted but later explanted or revised due to inadequate pain relief, n = 29). Patients who underwent explantation for other reasons (n = 4) were excluded. Opioid purchase data from January 1995 to March 2016 were retrieved from national registries.ResultsHigher preimplantation opioid doses associated with unsuccessful SCS (ROC: AUC = 0.66, p = 0.009), with 35 morphine milligram equivalents (MME)/day as the optimal cutoff value. All opioids were discontinued in 23% of patients with successful SCS, but in none of the patients with unsuccessful SCS (p = 0.004). Strong opioids were discontinued in 39% of patients with successful SCS, but in none of the patients with unsuccessful SCS (p = 0.04). Mean opioid dose escalated from 18 ± 4 MME/day to 36 ± 6 MME/day with successful SCS and from 22 ± 8 MME/day to 82 ± 21 MME/day with unsuccessful SCS (p < 0.001).ConclusionsHigher preimplantation opioid doses were associated with SCS failure, suggesting the need for opioid tapering before implantation. With continuous SCS therapy and no explantation or revision due to inadequate pain relief, 39% of FBSS patients discontinued strong opioids, and 23% discontinued all opioids. This indicates that SCS should be considered before detrimental dose escalation.  相似文献   
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ObjectiveTo analyze the effects of electrolysis, through a medium frequency current, associated to aerobic physical activity in the body composition of young women.MethodsThe study was composed of 34 sedentary women (24.35 ± 4.43 years, 71.30 ± 7.08 kg, 1.61 ± 0.06 m, 27.31 ± 1.67 kg/m2) which were evaluated for their anthropometric measures and body composition. The volunteers were randomly assigned to two group: Electrolyphysis plus Aerobic Exercise (gEEA): 17 volunteers were submitted to the application, for 60 min , of the Aussie current, followed by aerobic physical activity (77% of HRmax) on the trampoline for 40 min, through video-lessons of Jump; and Aerobic Exercise group (gEA): 17 volunteers performed only physical activity following the same parameters mentioned above. Each group performed its protocols twice weekly, for 5 weeks, totaling 10 sessions. For the data analysis, measures repeated ANOVA was performed to compare the means of the variables analyzed before and after the treatment protocols using the SPSS - 21.0 software, adopting a p ≤ 0.05.ResultsAlthough gEEA decreased suprailiac skinfold (p = 0.04), abdominal skinfold (p = 0.03) and circumference at umbilical scar (p = 0.02) in an intragroup analysis, these means differences in anthropometric measures were not important between-groups (p > 0.05). Furthermore, there were no effect of treatment on body composition (p > 0.05).ConclusionTo this studied condition, our results suggested that application of medium frequency electrolysis did not enhance the losses on anthropometric measures and body composition.  相似文献   
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Cutaneous leiomyomas are rare benign smooth‐muscle tumors. These lesions are distinguished based on their cell of origin and are subclassified as pilar leiomyoma, angioleiomyoma, and genital‐type leiomyoma. Nipple leiomyoma is the least common genital‐type leiomyoma, arising from the dartoic muscle cell of the nipple. Histologic examination of the lesion is necessary for definitive diagnosis, and these uncommon tumors can pose a diagnostic challenge. We describe herein a series of six nipple leiomyomas with a spectrum of histologic appearances.  相似文献   
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目的探究面肌痉挛患者微血管减压术(MVD)中异常肌反应(AMR)的变化特点与术后疗效的关系。方法回顾性分析73例MVD术中采用AMR全程定量化监测患者的AMR变化特点,减压操作前AMR阈值较基础阈值升高≥1倍为A1组、1倍为A2组,手术结束时AMR完全消失为B1组、未消失为B2组,B2组中AMR阈值较基础阈值升高≥1倍为B2a组、1倍为B2b组,对各组的术后疗效进行对比分析。结果 A1组21例中,19例立即治愈,1例延迟治愈,1例未愈; A2组52例中,35例立即治愈,9例延迟治愈,8例未愈。A1组较A2组疗效好(P=0. 046)。B1组50例中,42例立即治愈,5例延迟治愈,3例未愈; B2组23例中,12例立即治愈,5例延迟治愈,6例未愈。B1组较B2组疗效好(P=0. 003)。B2 a组的治愈比例较B2 b组高(分别为14/16、3/7),差异有统计学意义(P=0. 045)。结论 AMR在术中的变化特点对术者有重要参考意义,AMR在减压前升高、在手术结束时完全消失、未消失但升高较基础阈值≥1倍者术后疗效相对较好。  相似文献   
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观察并评估角膜电刺激对糖尿病大鼠前部缺血性视神经病变(AION)模型的影响。方法:实验 研究。健康雄性Sparague-Dawley大鼠40只,随机分组后抽出8只作为正常大鼠组。余下32只先予 以链脲佐菌素腹腔注射建立糖尿病大鼠模型,将造模成功的大鼠随机抽出8只作为糖尿病组,余下 24只糖尿病大鼠采用孟加拉玫瑰红联合532 nm激光方法建立AION大鼠模型。将24只造模成功的 AION大鼠随机分成3组,每组8只,分别为AION模型组,不予任何处理;电刺激组,予以角膜电刺 激(刺激参数为:电流1 mA,频率20 Hz,波宽1 ms/phase,刺激时间1 h,隔日1次,刺激2周);假电 刺激组,电极安放位置与电刺激组相同,仅不接通电源。2周后5组大鼠进行眼底照相、光学相干断 层扫描和视觉诱发电位,然后处死,行视网膜及视神经冰冻切片,苏木精伊红染色观察。数据采用 单因素方差分析和LSD-t检验进行分析。结果:正常大鼠组视盘上半部视网膜厚度为(211±13)μm, 糖尿病大鼠组为(206±16)μm,AION模型组为(240±54)μm,假电刺激组为(216±11)μm,电刺 激组为(198±4)μm,5组视盘上半部视网膜厚度差异有统计学意义(F=2.854,P=0.038)。其中AION 模型组视盘上半部视网膜厚度高于正常组、糖尿病组、电刺激组,差异均有统计学意义(P<0.05); 正常组与糖尿病组差异无统计学意义,AION模型组与假电刺激组未见明显差异。视觉诱发电位示 AION模型组N1潜伏期较电刺激组延长,差异有统计学意义(t=4.1,P<0.001);AION模型组P1潜伏 期较正常组、糖尿病组、假电刺激组、电刺激组延长,差异均有统计学意义(t=4.1、2.5、2.6、3.2, P<0.05);电刺激组N1-P1波幅大于假电刺激组,差异有统计学意义(t=4.0,P<0.001)。结论:角膜电 刺激能促进糖尿病大鼠前部缺血性视神经病变模型肿胀的视盘变薄,加速视盘水肿的消退,同时在 一定程度上改善视功能。  相似文献   
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