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111.
BACKGROUND: Regional anaesthesia for ophthalmic surgery is generally accomplished by peri- or retrobulbar techniques. Depending on the duration of ophthalmic surgery, reblock might become necessary. Our goal was to invent a catheter technique for ophthalmic regional anaesthesia that enables the user to administer local anaesthetics intraoperatively into the peri- or retrobulbar space continuously. METHODS: Twenty-five adult cadaver orbits of normal size and anatomy were used for the experiments. A flexible catheter was introduced transcutaneously or transconjunctivally into the extra- or intraconal space. Methylene blue solution was injected through the catheter. RESULTS: Using the same transcutaneous retro- and peribulbar technique, it was possible to introduce flexible catheters into a proper position of the cadaver orbits. The injected dye was found intra- or extraconally. CONCLUSION: Examining the spread of the dye in the orbit, we concluded that it is possible to provide ophthalmic anaesthesia for surgery through an indwelling catheter. We proved that continuous or intermittent administration of a local anaesthetic agent into the extra- or inraconal space can be achieved and this technique may allow us to maintain anaesthesia as long as it is necessary.  相似文献   
112.
BACKGROUND: Usually general anaesthesia is chosen if ophthalmic surgery of longer duration is expected. Our goal was to introduce a flexible catheter preoperatively into the extra- or intraconal space and to provide sufficient anaesthesia by continuous administration of a local anaesthetic via the catheter. METHODS: The continuous anaesthetic technique was applied in 28 patients undergoing vitreoretinal surgery. An indwelling catheter was introduced in 20 patients into the intraconal and in 8 patients into the extraconal space. In 6 patients, the position of the catheter was controlled by ultrasound examination prior to the injection of the local anaesthetic agent. RESULTS: For all patients adequate anaesthesia could be achieved and maintained with continuous retrobulbar administration (CRA) of a local anaesthetic by catheter. There were two patients who experienced moderate pain intraoperatively during continuous peribulbar administration (CPA). No complications occurred with the placement of the catheters. The catheter did not disturb the surgeon or the process of the ophthalmic surgery. CONCLUSIONS: Continuous administration of a local anaesthetic agent via an indwelling catheter into the intraconal space allowed ophthalmic anaesthesia without time restriction. Thus, CRA is a good alternative to general anaesthesia for patients undergoing long-lasting ophthalmic surgery.  相似文献   
113.
【目的】探讨注意缺陷/多动障碍(ADHD)各亚型局部脑血流(rCBF)特点以及与不同临床类型的关系。【方法】用单光子发射计算机断层扫描(SPECT)测定了40例ADHD患儿和11例正常儿童rCBF灌注情况。【结果】定性分析结果显示,ADHD患儿低疋BF灌注量的发生率(57.5%)高于正常儿童(9%),低灌注部位涉及额叶、颞叶、枕叶和丘脑,以额叶发生率最高;伴有多动一冲动组低rCBF注量的发生率(66.7%)高于注意缺陷组(47.3%),同时,伴有多动一冲动组中在所有疋BF降低的脑区中,左侧占14例次,右侧占10例次,左右侧rCBF差异有显著性。【结论】额叶rCBF降低与ADHD行为抑制缺陷相关,同时左侧脑区血流下降与病情的严重程度相关。  相似文献   
114.
目的探讨螺旋CT多平面重建对中国人视神经管区解剖特征的研究价值,为鼻内窥镜下手术提供相应数据。方法对100例椎动脉造影的患者行头部螺旋CT水平位扫描,通过多平面重建,对视神经管及相关结构进行测量。结果(1)前鼻棘到蝶窦前壁最近距离,男(56.69±3.34)mm,女(54.09±4.31)mm。前鼻棘到垂体窝最近距离,男(75.19±3.13)mm,女(71.55±3.19)mm。(2)前鼻棘到视神经管眶口的距离,男(71.08±3.94)mm,女(67.53±3.63)mm;该平面与鼻底平面所成上仰角(38.64±4.80)°;该平面与蝶窦窦底平面所成上仰角(59.63±8.84)°;该平面与正中矢状面的外偏角,左(12.04±1.21)°,右(12.20±1.29)°。(3)蝶嘴到视神经眶口连线的距离,左(22.05±0.26)mm,右(22.05±0.25)mm;蝶嘴到视神经眶口连线与正中矢状面的外偏角(39.50±0.59)°。(4)蝶嘴到颈内动脉隆突最突点距离,左侧(19.65±0.26)mm,右侧(20.07±0.24)mm。蝶嘴到颈内动脉隆突最突点连线与正中矢状面的外偏角(30.32±0.52)°。结论螺旋CT多平面重建能对视神经管区精细解剖结构做出准确的观测;能对蝶筛区病变的确诊及手术治疗提供指导。  相似文献   
115.
改革开放以来的24年中,长三角15个城市地区存在比较明显的经济增长趋同现象,同时经历了首先快速趋同而后缓慢趋异的动态变化过程,其转折点是二十世纪九十年代初期;不包括上海在内的长三角14个城市地区的经济增长同样存在趋同现象,也经历了先趋同后趋异的变化过程。二者存在着比较明显的差别:前一时段14城市地区经济增长趋同的速度较15城市为慢,而后一时段经济增长趋异的速度较15城市地区为快。长三角地区经济增长趋同及其变化过程的主要作用机制不是资本边际报酬递减,不是技术扩散和转移,也不是结构变迁或生产要素跨部门的再配置,而是经济全球化背景下国际资本(外商直接投资)转移的空间选择及其演化规律。  相似文献   
116.
Peripheral nerve blocks (PNBs) in paediatric patients are usually used as an adjunct to general anaesthesia, providing intra- and postoperative analgesia. These blocks provide good-quality analgesia preventing morbidity related to pain and reducing adverse effects from systemic analgesics. PNBs aid early patient recovery and discharge, which is essential in day-case surgery. Like all invasive techniques, PNBs are associated with complications and adverse effects. They should therefore be performed only after careful analysis of the risk:benefit ratio for each child. This article discusses a general approach to PNBs in children. It covers a small selection of limb and trunk blocks, and discusses the benefit of ultrasound guidance.  相似文献   
117.
locStra is an ‐package for the analysis of regional and global population stratification in whole‐genome sequencing (WGS) studies, where regional stratification refers to the substructure defined by the loci in a particular region on the genome. Population substructure can be assessed based on the genetic covariance matrix, the genomic relationship matrix, and the unweighted/weighted genetic Jaccard similarity matrix. Using a sliding window approach, the regional similarity matrices are compared with the global ones, based on user‐defined window sizes and metrics, for example, the correlation between regional and global eigenvectors. An algorithm for the specification of the window size is provided. As the implementation fully exploits sparse matrix algebra and is written in C++, the analysis is highly efficient. Even on single cores, for realistic study sizes (several thousand subjects, several million rare variants per subject), the runtime for the genome‐wide computation of all regional similarity matrices does typically not exceed one hour, enabling an unprecedented investigation of regional stratification across the entire genome. The package is applied to three WGS studies, illustrating the varying patterns of regional substructure across the genome and its beneficial effects on association testing.  相似文献   
118.
Effective prevention of chronic postoperative pain is an important clinical goal, informed by a growing body of studies. Peri-operative regional anaesthesia remains one of the most important tools in the multimodal analgesic toolbox, blocking injury-induced activation and sensitisation of both the peripheral and central nervous system. We review the definition and taxonomy of chronic postoperative pain, its mechanistic basis and the most recent evidence for the preventative potential of multimodal analgesia, with a special focus on regional anaesthesia. While regional anaesthesia targets several important aspects of the mechanistic pathway leading to chronic postoperative pain, evidence for its efficacy is still mixed, possibly owing to the heterogeneity of risk profiles within the surgical patient, but also to variation in techniques and medications reported in the literature.  相似文献   
119.
区域性空中医疗救护体系构建   总被引:1,自引:0,他引:1  
目的探讨构建区域性空中医疗救护体系的必要性、可行性和体系构建后的运行。方法综合分析外军及联合国维和部队空中救护体系,参考我国灾害救援中的有关经验。结果指挥系统、区域性医疗救援中心、运输工具、空中医疗救援队及现场分类救援力量是该体系构建的重点。结论区域性空中医疗救护体系是未来的一个重点方向。  相似文献   
120.
BackgroundThe head and neck region has rich regional lymphatic network, with a theoretical risk on contralateral metastasis from oropharyngeal cancer (OPC). There is a long-standing convention to irradiate the great majority of these tumors electively to both sides of the neck to reduce the risk of contralateral regional failure (cRF), but this can induce significant toxicity. We aimed to identify patient groups where elective contralateral irradiation may safely be omitted.MethodsPubMed and EMBASE were searched for original full-text articles in English with a combination of search terms related to the end points: cRF in OPC primarily treated by radiotherapy only to the ipsilateral neck and identifying predictive factors for increased incidence of cRF. The data from the identified studies were pooled, the incidence of cRF was calculated and the correlation with different predictive factors was investigated.ResultsEleven full-text articles met the inclusion criteria. In these studies, 1116 patients were treated to the ipsilateral neck alone. The mean incidence of cRF was 2.42% (range 0–5.9%, 95% CI 1.6–3.5%). The incidence of cRF correlated only with T-stage (p = 0.008), and involvement of midline (p = 0.001). However, the significant correlation with T-stage can be explained by the very low incidence of cRF among T1 (0.77%), and disappeared when the incidence of cRF was compared between T2, T3,and T4 (p = 0.344).ConclusionThe incidence of cRF in patients with OPC is very low, with involvement of midline providing the most significant prognosticator. These results call for trials on unilateral elective irradiation in selected groups.  相似文献   
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