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91.
目的:探讨岩斜区肿瘤外科治疗手术入路选择。方法:回顾性分析我院自1997年至2000年6月显微外科手术治疗的17例岩斜区肿瘤。12例肿瘤直径大于4cm。采用6种手术入路:颞下-小脑幕;天幕上下联合;颞下-乙状窦前;枕下乳突后;枕下远外侧;额眶颧入路。结果:肿瘤全切除12例(71%),术后恢复良好者11例(65%),术后新增颅神经损害6例(35%)。结论:选择和掌握适合的颅底手术入路,采用显微外科技术入路,采用显微外科技术切除岩斜区肿瘤可取得满意效果。  相似文献   
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A new type of ultra-short acting -blocker which might prove advantageous in treating acute arrhythmias was designed, synthesized and investigated. Based on the soft drug inactive metabolite approach, the inactive phenylacetic acid metabolite of both metoprolol and atenolol was reactivated by esterification with sulfur-containing aliphatic alcohols. Since the sulfur-containing moieties are labile to the ubiquitous esterases, the new compounds should be inactivated by a one step enzymatic cleavage back to the inactive phenylacetic acid derivative. Pharmacological and pharmacokinetic profiles of the new compounds were evaluated in rats and rabbits. Isoproterenol-induced tachycardia was inhibited with short-term infusion of each compound. This tachycardia blocking effect rapidly disappeared upon termination of infusion, while -blocking activity was 2–4-fold longer after comparable doses of the short-acting -blocker, esmolol. The rapid recovery from the -receptor blockade is believed due to fast hydrolysis of the soft drugs in the body. This is supported from in vitro results showing the tl/2 of esmolol is about 10-fold longer than the new soft drugs in rat, rabbit, dog and human blood. Hydrolysis studies in phosphate buffered solutions indicated that the esters are labile to base-catalyzed hydrolysis. However, the relative t1/2 values measured in biological media compared to phosphate buffered solution clearly support rapid enzymatic cleavage of the soft drugs. Interestingly, one of the soft -blockers, the sulfonyl ester derivative, showed a unique property of exhibiting good -receptor blocking activity without significant hypotensive action.  相似文献   
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95.
目的:为获得经岩骨入路颈静脉孔区手术相关的国人解剖学参数,指导临床实践。方法:通过解剖观测30 侧国人尸头,对有关岩骨入路数据进行测量。结果:鼓环~颈静脉球顶距离为(4.84±3.84)m m ,鼓环~面神经距离为(2.71±0.81)m m ,后半规管~颈静脉球顶距离为(4.99±4.41)m m ,膝状神经节~颈内动脉膝部距离为(7.71±1.47)m m ,面神经垂直部~颈静脉球距离为(5.67±2.24)m m 。结论:术中如能注意相关解剖学参数,可提高治愈率,减少并发症和死亡率  相似文献   
96.
Summary  The incidence of high cervical disc lesions is extremely rare, and the mechanism of their development is unclear. We report these three cases, and discuss the possible mechanisms. We also describe surgical strategies for these lesions.  The first and second cases were an 82-year-old male and an 84-year-old male with retro-odontoid disc hernia. The third was an 83-year-old female with a herniated disc at C2/C3. To investigate Aetiological mechanisms of these lesions, we examined the findings on cervical images in extension and flexion, and compared the results in a younger than 80-year-old group and an older than 80-year-old group.  The patients underwent surgery via a posterolateral intradural approach. Wide laminectomy and incision of the dentate ligaments enabled access to the ventral space of the upper cervical spinal canal and sufficient decompression. All patients became ambulatory postoperatively without special fixation of the cervical spine. In the younger group, the level mostly loaded during cervical movement was C5/6, however, the levels in the older group were C2/3 and C3/4.  In elderly patients, less mobilization of the middle and/or lower cervical spine due to spondylotic change causes overloading at higher levels resulting in high cervical disc lesions. Retro-odontoid disc lesions can be caused by a herniated disc at C2/C3, which migrates upward. Regarding surgical strategy, the posterolateral intradural approach is less invasive and more advantageous for these lesions.  相似文献   
97.
98.
Multiple intracranial aneurysms: A high risk condition   总被引:1,自引:0,他引:1  
Summary There is still a relative silence in the literature on what policy should be followed in treating multiple aneurysms. The main risks are: bleeding of a formerly asymptomatic aneurysm during the haemodynamic tides of the peri-operative period; aneurysm(s) can be hidden on angiograms and tend to be overlooked easier in case of an already revealed aneursym; misjudgement of the ruptured one as a silent additional aneurysm, therefore left for second stage surgery.This paper, based on a material of 330 operations for multiple aneurysms, focuses on these problems. It advocates the one stage complete repair of all lesions using both options of bilateral pterional craniotomies or the contralateral approach. But it also describes those silent aneurysms which safely could be clipped later. Hazards and disadvantages concerning the more aggressive surgery proved to be less significant than the natural history of multiple aneurysms represents.Presented at the EANS Wintermeeting on High Risk Neurosurgery, Budapest, February 20–23, 1991.  相似文献   
99.
颈静脉球解剖变异对经内镜行岩斜坡区病变手术的影响   总被引:1,自引:0,他引:1  
目的 了解颈静脉球的解剖变异对颞骨径路在内镜下行桥小脑角区病变手术的影响。方法 在20例40侧成人尸头上模拟颞骨径路内镜手术,测量相关数据。结果 颈静脉球高度为左侧(7.39±2.11)mm,右侧(9.05±3.10)mm;宽度为左侧(6.28±1.25)mm,右侧(6.34±0.79)mm;颈静脉球顶距鼓室天盖、后半规管上、下缘、上半规管顶点、内淋巴囊上缘、面神经锥段中点、内听道下缘之间距离分别为:(16.05±3.34)mm、(8.73±3.11)mm、(3.13±1.83)mm、(14.63±3.33)mm、(5.01±2.88)mm、(3.70±3.36)mm、(5.03±3.19)mm。结论 高位颈静脉球对内镜手术有一定影响,但相对非内镜手术而言要小,高位颈静脉球的定义依不同的术式而不同。  相似文献   
100.
目的 探讨经迷路进路听神经瘤切除术后脑脊液漏发生的影响因素及处理方法。方法1999年以来采用迷路进路或扩大迷路进路听神经瘤切除术 85例 ,前 4 1例采用传统关闭术腔技术 ,后4 4例对关闭技术进行改良 ,分析其脑脊液漏的发生率。发生脑脊液漏者行保守或手术治疗。结果传统关闭技术组中脑脊液漏的发生率为 19 5 % ( 8 4 1) ,改良关闭技术组中脑脊液漏的发生率为 2 3%( 1 4 4 ) ,两组差异有显著性意义 (P =0 0 13)。传统关闭技术组中脑脊液漏多数发生在大型听神经瘤中 ,其发生率随肿瘤增大有上升的趋势。 9例脑脊液漏的患者中 ,3例经保守治疗 ;6例经手术修补成功 ,其中 5例 1次修补成功。结论 改良关闭术腔技术可显著降低经迷路进路听神经瘤切除术后脑脊液漏的发生率 ,手术修补为终止脑脊液漏的有效措施  相似文献   
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