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91.
Imaging the infant brain with MRI has improved our understanding of early neurodevelopment. However, head motion during MRI acquisition is detrimental to both functional and structural MRI scan quality. Though infants are typically scanned while asleep, they commonly exhibit motion during scanning causing data loss. Our group has shown that providing MRI technicians with real-time motion estimates via Framewise Integrated Real-Time MRI Monitoring (FIRMM) software helps obtain high-quality, low motion fMRI data. By estimating head motion in real time and displaying motion metrics to the MR technician during an fMRI scan, FIRMM can improve scanning efficiency. Here, we compared average framewise displacement (FD), a proxy for head motion, and the amount of usable fMRI data (FD ≤ 0.2 mm) in infants scanned with (n = 407) and without FIRMM (n = 295). Using a mixed-effects model, we found that the addition of FIRMM to current state-of-the-art infant scanning protocols significantly increased the amount of usable fMRI data acquired per infant, demonstrating its value for research and clinical infant neuroimaging.  相似文献   
92.
《Brain stimulation》2020,13(6):1668-1677
BackgroundEndovascular delivery of current using ‘stentrodes’ – electrode bearing stents – constitutes a potential alternative to conventional deep brain stimulation (DBS). The precise neuroanatomical relationships between DBS targets and the vascular system, however, are poorly characterized to date.ObjectiveTo establish the relationships between cerebrovascular system and DBS targets and investigate the feasibility of endovascular stimulation as an alternative to DBS.MethodsNeuroanatomical targets as employed during deep brain stimulation (anterior limb of the internal capsule, dentatorubrothalamic tract, fornix, globus pallidus pars interna, medial forebrain bundle, nucleus accumbens, pedunculopontine nucleus, subcallosal cingulate cortex, subthalamic nucleus, and ventral intermediate nucleus) were superimposed onto probabilistic vascular atlases obtained from 42 healthy individuals. Euclidian distances between targets and associated vessels were measured. To determine the electrical currents necessary to encapsulate the predefined neurosurgical targets and identify potentially side-effect inducing substrates, a preliminary volume of tissue activated (VTA) analysis was performed.ResultsSix out of ten DBS targets were deemed suitable for endovascular stimulation: medial forebrain bundle (vascular site: P1 segment of posterior cerebral artery), nucleus accumbens (vascular site: A1 segment of anterior cerebral artery), dentatorubrothalamic tract (vascular site: s2 segment of superior cerebellar artery), fornix (vascular site: internal cerebral vein), pedunculopontine nucleus (vascular site: lateral mesencephalic vein), and subcallosal cingulate cortex (vascular site: A2 segment of anterior cerebral artery). While VTAs effectively encapsulated mfb and NA at current thresholds of 3.5 V and 4.5 V respectively, incremental amplitude increases were required to effectively cover fornix, PPN and SCC target (mean voltage: 8.2 ± 4.8 V, range: 3.0–17.0 V). The side-effect profile associated with endovascular stimulation seems to be comparable to conventional lead implantation. Tailoring of targets towards vascular sites, however, may allow to reduce adverse effects, while maintaining the efficacy of neural entrainment within the target tissue.ConclusionsWhile several challenges remain at present, endovascular stimulation of select DBS targets seems feasible offering novel and exciting opportunities in the neuromodulation armamentarium.  相似文献   
93.
Central illustration: geographic distribution of the 49 centres participating in the FRENSHOCK registry (35 academic hospitals, 10 general hospitals and four private clinics). Inclusion per centre varied from 1 to 72 patients.
  相似文献   
94.
目的探析经鼻高流量湿化氧疗用于小儿先心病术后治疗中的效果以及护理措施。方法2014年9月—2017年10月在郑州儿童医院外科监护室接受手术治疗的先心病患儿中随机抽取130例,根据术后氧疗方法不同分组:对照组患儿术后给予常规面罩吸氧,观察组患儿术后给予经鼻高流量湿化氧疗,2组患儿均给予优质术后护理,对比2组的血气指标、住院时间等。结果2组患者氧疗后24h、48h的血氧饱和度差异无统计学意义,在氧疗后24h的PaCO2水平差异无统计学意义,而在氧疗后24h和48h的氧合指数,观察组明显高于对照组,差异有统计学意义(P<0.05);2组ICU入住时间和总住院时间差异无统计学意义(P>0.05)。结论经鼻高流量湿化氧疗的应用提高先心病患儿术后的舒适度,改善呼吸状况,值得推广。  相似文献   
95.
目的: 评估液相色谱-电喷雾串联质谱(LC-ESI-MS/MS)分析人全血中环孢素的基质效应,并探究其发生机理。方法: 全血裂解物的蛋白沉淀上清液用作全血基质。分别用乙腈水溶液和全血基质配制等浓度环孢素A(CyA)、环孢素C(CyC)的质控样品。分别在添加H+、NH4+和Na+的流动相中,用LC-ESI-MS/MS的MRM模式检测质控样品中CyA,CyC的[M+H]+、[M+NH4]+和[M+Na]+(M=CyA,CyC)峰面积,以其计算基质效应因子;用MS Scan模式检查质控样品中CyA、CyC色谱流出峰的质谱离子组成情况,用于判断基质效应原因。结果: 在添加H+、NH4+和Na+的流动相中,全血基质中CyA、CyC基质效应因子分别为-76.6%~-54.0%、-86.0%~-55.3%和-42.8%~-34.1%。在加H+、加NH4+流动相中,标准液加全血基质的CyA、CyC色谱峰的质谱中出现丰度很高的[M+Na]+和[M+K]+,在加Na+流动相中它们出现丰度很高的[M+K]+,而对应的定量离子[M+H]+、[M+NH4]+或[M+Na]+的丰度显著降低。结论: 全血基质对环孢素的LC-ESI-MS/MS分析产生明显的基质效应,其原因与基质中Na+、K+同添加在流动相中用于辅助电离的H+、NH4+或Na+竞争与环孢素加合,导致定量目标加合离子丰度显著降低有关。  相似文献   
96.
Summary We present a case of blindness and Anton’s syndrome in a psychiatric patient with late diagnosis of a giant frontal meningioma. The criteria for advanced diagnostic imaging in the psychiatric population are discussed. We conclude that MR or CT scan is indicated in psychiatric in-patients who fail to improve with standard psychiatric treatment. This strategy should be submitted to a cost-benefit analysis.  相似文献   
97.
目的探讨重度脑外伤患者早期高压氧治疗的临床效果。方法重度脑挫裂伤患者56例,入院时患者的格拉氏哥评分(glasgowcomascale,GCS)为3~8分,均于入院1h内行去骨瓣减压术或同时行血肿清除术;20例在伤后5~20h内行早期高压氧(HBO)治疗,36例在脑水肿消退后(7~18d)行常规HBO治疗。两组均治疗2个疗程。观察3周后重新GCS评分,6个月后进行格拉氏哥结果评级(glasgowoutcomescale,GOS)。结果两组患者治疗后3周GCS评分和6个月后GOS评分差异具有统计学意义。早期HBO治疗组明显优于常规HBO治疗组。结论早期的HBO治疗可以及时提高血氧含量,阻止恶性缺血缺氧的发生。重度脑挫裂伤患者术后在可能的条件下应尽早行HBO治疗,以提高患者的生存质量。  相似文献   
98.
目的探讨帕金森病(Parkinson's disease,PD)苍白球腹后部毁损术(posteroventral pallidotomy,PVP)后再行丘脑底核(subthalamic nucleus,STN)脑深部电刺激术(deep brain stimulation,DBS)的可行性、术中电生理学特点和治疗结果。方法应用MR和微电极记录技术进行靶点定位,对12例单侧PVP术后症状再次加重的PD患者实施STN-DBS手术,其中4例行毁损灶对侧的STN-DBS,8例行双侧STN-DBS。结果STN-DBS对本组12例PD患者症状有不同程度的改善,双侧STN-DBS的效果尤为明显,术后3个月的UPDRS运动及ADL评分较术前明显减少(P<0.05或0.01),美多巴的用量明显减少(P<0.01),无明显术后并发症。术中电生理记录显示毁损灶同侧的细胞放电明显低于正常情况。结论曾行单侧PVP的PD患者如面临二次手术,可以选择DBS手术,以双侧STN的DBS效果最好,可减少药物用量。  相似文献   
99.
目的应用BOLD-MfRI研究正常人及脑肿瘤患者听觉性中英文语言皮层定位并探讨其对脑肿瘤的临床应用价值。方法应用MarconiEclipse1.5T超导型磁共振机,30例受试者,行听觉性中、英文语言刺激的BOLD-MfRI,以定位正常人和脑肿瘤患者的语言皮层。结果正常人听觉性中英文语言任务激活区域均以左侧大脑半球为主,主要有双侧颞横回、Wernicke区、Broca区和SMA区。中文语言任务刺激时脑区激活面积和程度比英文语言任务大,但英文语言任务时可见更明显的Broca区和角回激活。累及功能皮层的脑肿瘤患者患侧半球可见残留部分功能激活区,但激活区移位,分布弥散,激活程度及范围较正常人略增高。未累及功能皮层者功能区定位与正常人大致相同。结论BOLD-MfRI是一种有效而无创的功能皮层定位方法,有利于脑肿瘤的精确定位诊断并指导临床治疗。  相似文献   
100.
Objectives. Traditional deep brain stimulation (DBS) at the subthalamic nucleus (STN) has proved to be efficacious on core Parkinsonian symptoms. However, very disabling l ‐dopa–induced abnormal involuntary movements (AIMs) and axial signs are slightly affected, suggesting that we target less conventional targets. Our candidates for DBS were the globus pallidus internus (GPi) plus the intralaminar thalamic complex (Pf or CM), given its extensive functional links with basal ganglia nuclei. Materials and Methods. The routine utilization of our innovative stereotactic apparatus allows us to implant, at the same time, both the CM‐Pf complex together with the GPi in six Parkinson disease patients. Both intraoperative and postoperative neurophysiologic assessments helped us recognize functional subregions while optimizing implantation of electrodes. Unified Parkinson disease rating scale (UPDRS) motor scores, AIMs, and freezing were carefully blindly evaluated for each condition. Results. A significant amelioration of UPDRS scores was achieved by simultaneous activation of both targets. CM‐Pf activation was only slightly effective in reducing rigidity and akinesia, but more efficacious on freezing. Not surprisingly, AIMs were peculiarly decreased by the activation of the permanent electro‐catheter in the posteroventral GPi. Conclusions. These findings confirm that, in selected patients, it is conceivable to target structures other than the conventional STN in order to maximize clinical benefit.  相似文献   
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