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Objective To investigate the effects of different degrees of neuromuscular blockade (NMB) induced by rocuronium on facial nerve evoked-electromyographic (EEMG) monitoring in patients undergoing resection of acoustic neuroma.Methods Thirty-five ASA Ⅰ or Ⅱ patients of both sexes,aged 20-64 yr,with body mass index ≤30 kg/m2,scheduled for elective resection of acoustic neuroma under general anesthesia,were included in the study.Anesthesia was induced with midazolam,fentanyl and propofol.The patients were mechanically ventilated after tracheal intubation.Facial nerve EEMG monitoring and peripheral NMB monitoring were performed simultaneously during operation.Facial nerve EEMG was monitored using the Epoch XP2000 multichannel electrophysiological nerve monitoring system (Axon Co.,USA),facial nerve was stimulated and evoked potential of orbicularis oculi was recorded during operation.Peripheral NMB degrees were monitored with TOF-Watch SX monitor (Organon Co.Holland).After rocuronium 0.6 mg/kg was injected intravenously,the facial nerve EEMG responses were monitored when the degree of NMB (T1) was at 100％,75％,50％,25％ and 0 of the control height.The amplitude and latency of EEMG were recorded.The amplitude reservation ratio (the ratio of the amplitude of EEMG monitored to the baseline value) was calculated.Linear correlation of the amplitude reservation ratio or latency of EEMG with the degree of NMB was analyzed.Results No EEMG response was elicited when the degree of NMB was 100％ in 6 patients.The lirear regression equation of the interaction between the degree of NMB (X) and the amplitude reservation ratio (Y) was Y =1 - 0.787 X,the coefficient of determination was 0.898 ( P ＜ 0.05) and the correlation coefficient was - 0.947 ( P ＜ 0.05).The correlation coefficient between the latency of EEMG and the degree of NMB was 0.328 ( P ＜ 0.05).Conclusion When the degree of NMB is maintained at 25 ％-50％,facial nerve EEMG can be monitored effectively and body movement can be avoided during resection of acoustic neuroma.
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ObjectiveTo study the methods of how to protect facial nerve function following complete resection of acoustic neurinomas and the value of the techniques of F wave assisted electrophysiological monitoring intraoperatively.Methods Retrospectivelysummarizing theresultsof combining three electrophysiological monitoring techniques such as nasal muscle F wave recording,online EMG and triggered EMG to monitor 46 cases of microoperations for acoustic neurinomas intraoperatively during the period of Feb.2004 to Dec. 2008. Correlating every intraoperative monitoring index with their follow-up results of facial nerve function 1 day and 6 months after their operations.The tendency of the two continuous monitoring techniques between nasal F wave recording and online EMG of facial muscles has also been studied in this paper. Results Among 46 cases of acoustic neurinomas, 45(97.83 %) tumors have been totally resected, and 1 (2.17 %) tumor subtotally resected,lcase (2.17 %)died after operation,and 2ases occurred the leakage of cerebrospinal fluid(CSF) which have been cured through conservative treatment. The whole anatomic protection rate of facial nerve is 97.83 %,and their functional protection rates 6 months after operation are:HB Ⅰ - Ⅱ,75.56 %;Ⅲ-Ⅳ,22.22 % and Ⅴ-Ⅵ,2.22 %.The completely accordant rate between the intraoperative findings of nasal F wave recording and online EMG is 52.17 %, partially accordant rate is 45.65 %, and totally opposite rate is 2.17 % (x2 趋势= 6.113, P ＜0.05). The intraoperative monitoring indexes in nasal muscle F wave recording are correlated well with the facial nerve function in the 6th month' s follow-up (κ=0.429, P ＜0.001).In triggered EMG monitoring after tumors being resected,the stimulus threshold ratio and maximum amplitude ratio of facial nerve between leaving brain stem part and inner acoustic porus part are also correlated well with the facial nerve function 6 months after operation(κ=0.576, P ＜0.001; κ=0.595, P ＜0.001). ConclusionNasal muscle F wa recording cooperated well with online EMG and triggered EMG intraoperatively and correlates well with the postoperative facial nerve function, so they should be routinely applied together intraoperatively.
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Objective To explore the value of F wave recording in evaluating facial nerve function and its pathological changes in the pressure-induced rat models of acoustic neurinoma. Methods 58 rats in different groups were conducted F wave recording and biotinylated dextran amine(BDA) retrograde tracing for their right facial nerve one week after establishing models. Their latencies, amplitudes and F/M rates were analyzed first. 72 hours after BDA was injected into right whisker muscle, the rats were infused with 4% polyoxymethylene, then pontines and facial nerves in the CPA cistern were obtained. Pontiues were cut into frozen sections for histochemical staining with avidin-horseradish peroxidase (HRP)-DAB and Nissl 's counterstaining, calculating the positive BDA neurons ratio(BDA+-N%)in facial nuclear. Facial nerves were cut and stained with toluidine blue for light-micrescope inspection, and/or stained for transmission electron microscope observation. Correlating F/M with BDA+-N% and the facial nerve pathological findings. Results F/M are 97.66 % and 97.48 % in normal and pseudo-operation group, respectively, when stimulus are 1.4 mA; while 77.13 %, 48.91% and 11.54 % in from small to large tumor model groups because F waves were delayed in latencies or increasinglylost (P <0.001). Similarly, BDA+-N% are 98.37 % and 97.96 % in the above two control groups, while 77.28 %, 48.28 % and 11.55 % in from small to large tumor model groups (P < 0.001). Thus F/M are positively correlated with their BDA+-N% in all groups (r =0.996,P <0.001). Facial nerve examinations under light and electron microscope show increasing pathological changes along with increasing "tumor" size. Conclusion The findings of F wave recording in facial nerve may reflect its functional status and pathological changes. Therefore, F wave detection may help electrophysiological monitoring during acoustic neurinoma resection and facial nerve function evaluation after surgery.
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AIM: To investigate the effects of Lobelia Chinensis Lour alkaloid (LCLA) on the proliferation of cultured vascular smooth muscle cells (VSMC) induced by ET-1. METHODS: Human umbilical artery VSMC was cultured and divided into five groups: ET group, ET+LCLA group, ET+BQ-123 group,ET+ staurosporine (ST) group and control group. The cell proliferation activity was subsequently quantified by cell counting kit-8 (CCK-8) and [3H]-TdR incorporation. Flow cytometry was used to examine cell cycle. Quantitative immunohistochemical technique was used to investigate the expression of proliferating cell nuclear antigen (PCNA) and confocal microscope was used to measure the fluorescent intensity of Ca 2+. Cytotoxicity was measured by Trypan blue exclusion and LDH colorimetry tests. RESULTS: BQ-123 (10 -6mol/L), ST (10 -7mol/L) and LCLA (100, 200 and 400 mg/L) inhibited the increase in cell number, [3H]-TdR incorporation, the percentage of the S phase and markedly decreased the expression of PCNA and fluorescent intensity of Ca 2+ in response to ET-1 of VSMC (P