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11.
周围神经端侧动脉套接后神经再生的研究 总被引:6,自引:2,他引:4
目的研究周围神经端侧动脉套接后神经再生的可能性及其特点. 方法取SD大鼠75只,在股骨中下段切断腓神经,将近断端逆转90度包埋于肌肉中.随机分为5组.A组:将截取的左颈总动脉套接于右侧正常胫神经侧方与腓总神经远端2 mm距离之间,缝合部胫神经外膜不予切除;B组:在胫神经套接部外膜开窗1.0 mm;C组:腓总神经切断14天后再予动脉套接,余同B组;D组:同B组,且于动脉套接部注入神经生长因子(neural growth factor, NGF)1 ml;E组:将腓总神经远端以端侧缝合形式直接缝合于胫神经的一侧,外膜开窗1.0 mm.术后4、8和12周分别行组织学、电镜和神经纤维计数等检查. 结果 4周时C、D及E组周边区域有神经纤维轴突和髓鞘再生,A组则无神经纤维生长; 8周时C、D及E组再生神经纤维较B组多,E组神经纤维较C、D组多,差异有统计学意义(P<0.05); 12周时C、D及E组神经纤维多于B组,差异有统计学意义(P<0.05);C组及D组有较丰富的神经再生,与神经端侧直接吻合的E组差异无统计学意义(P>0.05). 结论神经端侧2 mm距离动脉套接可作为修复周围神经损伤的一种可行方法. 相似文献
12.
Heubner回返动脉显微外科解剖及其临床应用 总被引:2,自引:0,他引:2
目的 :为前交通动脉复合体部位显微手术避免损伤Heubner回返动脉提供相关的应用解剖学资料。方法 :对经双侧椎动脉 (VA)、颈内动脉 (ICA)乳胶灌注的尸头标本 2 2例 ,按翼点入路方向 ,在手术显微镜下解剖观测 2 0例Heubner回返动脉的起点、管径、行径及其毗邻关系。 2例模拟手术操作。结果 :(1)本组观测到 4 3支回返动脉 ,其中 39支Heubher回返动脉 ;4支副Heubner回返动脉。 (2 )Heubner回返动脉 4 6 .5 % (2 0 / 4 3)起于A2 段 ,2 5 .6 % (11/ 4 3)起于A1段 ,2 7.9% (12 /4 3)起于前交通动脉 (ACOA)水平的大脑前动脉 (ACA)。 (3)Heubner回返动脉起点管径 :左侧 0 .81± 0 .2 1mm(0 .35~ 1.17mm) ;右侧 0 .84± 0 .2 6mm(0 .37~ 1.2 1mm)。 (4 )回返动脉发出后 ,与ACA反方向成锐角 ,沿A1上壁、外侧及后内侧 ,越过ICA两分叉 ,经大脑中动脉 (MCA)始段前面穿通入脑 ,少数回返动脉行走于前穿质 (APS)的后部。A1近端 3~ 5mm或中 1/ 3段穿通支少。结论 :在前交通动脉复合体部位手术时 ,A1近端 3~ 5mm或中 1/ 3段夹闭 ,并解剖寻找、剥离Heubner回返动脉 ,可避免损伤Heubner回返动脉及其它穿通支 ,最大限度减少术后并发症 相似文献
13.
目的 :探讨二维彩色多普勒超声及彩色血管三维超声在颈动脉疾病的诊断价值。材料方法 :疑为缺血性脑卒中患者 80例 ,行颈动脉彩色多普勒超声检查 ,其中 2 8例同时做彩色血管三维超声成像 ,5 5例经临床、CT、MRI证实为脑梗死。结果 :①本组 5 5例脑梗死 ,彩色多普勒超声发现 4 9例颈动脉粥样硬化斑。②有脑梗死的彩色血管三维血流图呈“串珠”状 ,而非脑梗死的彩色血管三维血流图呈连续“圆锥”状。结论 :彩色多普勒超声诊断颈动脉粥样硬化有良好的价值 ,三维彩超是二维彩色多普勒超声的有益补充。 相似文献
14.
目的 评价介入放射方法诊断治疗肢体创伤性动脉病变的效果。方法 8例肢体动脉创伤伴有远端肢体缺血改变,其中2例伴大出血,伤者接受了选择性患肢动脉造影检查;7例随后进行了动脉病变的血管腔内介入治疗。治疗方法包括动脉分支或主干栓塞、动脉内溶栓和血管内支架置放。结果 血管造影精确显示了动脉破裂、假性动脉瘤、血栓形成或动脉内膜损伤等病变性质。3例假性动脉瘤、3例动脉血栓病变综合应用介入治疗方法取代外科手术获得满意疗效。1例溶栓后证实动脉破裂和1例造影证实动静脉瘘后转手术治疗。结论 介入放射与外科方法相结合能明显提高肢体动脉创伤的诊断治疗水平,有效挽救伤者肢体和生命。 相似文献
15.
老年人血清胆红素水平与冠状动脉病变程度的关系 总被引:2,自引:0,他引:2
目的观察老年人血清胆红素与冠状动脉病变的关系。方法经冠状动脉造影确诊的冠心病患者80例,其中冠状动脉轻度狭窄组15例,中度狭窄组32例,重度狭窄组33例;另外选取冠状动脉造影正常者40例做对照。采用重氮苯磺酸法测定血清胆红素水平,并对胆红素与各因素进行直线相关分析。结果冠心病组血清胆红素水平明显低于正常对照组,血清胆红素水平与冠状动脉病变程度成显著负相关关系(r=-0.26,P<0.05)。结论冠心病患者血清胆红素水平较正常人明显降低。低血清胆红素可能是冠心病的一种危险因素。血清胆红素水平与冠状动脉狭窄程度有明显相关性。 相似文献
16.
Marcela Hernández Hoyos Piotr Orłowski Ewa Piątkowska-Janko Piotr Bogorodzki Maciej Orkisz 《International journal of computer assisted radiology and surgery》2006,1(1):51-61
The accuracy of 2D phase contrast (PC) magnetic resonance angiography (MRA) depends on the alignment between the vessels and
the imaging plane. PC MRA imaging of blood flow is challenging when the flow in several vessels is to be evaluated with one
acquisition. For this purpose, semi-automatic determination of the plane most perpendicular to several vessels is proposed
based on centerlines extracted from 3D MRA. Arterial centerlines are extracted from 3D MRA based on iterative estimation-prediction,
multi-scale analysis of image moments, and a second-order shape model. The optimal plane is determined by minimizing misalignment
between its normal vector and the centerlines’ tangent vectors. The method was evaluated on a phantom and on 35 patients,
by seeking the optimal plane for cerebral blood flow quantification simultaneously in internal carotids and vertebral arteries.
In the phantom, difference of orientation and of height between known and calculated planes was 1.2° and 2.5 mm, respectively.
In the patients, all but one centerline were correctly extracted and the misalignment of the plane was within 12° per artery.
Semi-automatic centerline extraction simplifies and automates determination of the plane orthogonal to one vessel, thereby
permitting automatic simultaneous minimization of the misalignment with several vessels in PC MRA. 相似文献
17.
Summary During 1978 to 1989, 235 patients were operated upon with 260 procedures for cervical carotid endarterectomy. The patients were classified according to the presence or absence of ischaemic symptomatology, and for symptomatic patients, according to the reversibility or persistance of ischaemic symptoms. So the selection of patients was: reversible ischaemia 46%, stroke 29%, asymptomatic patients 25%. In the stroke group, no patient was operated on as an emergency, the endarterectomy was only performed after stabilization of the clinical state. Three subgroups were included in patients operated on for asymptomatic carotid stenosis: casual discovery 40%, treatment of the second carotid artery (previous endarterectomy for symptomatic contralateral stenosis) 34%, and treatment of the second carotid artery (previous ECIC by-pass for contralateral carotid occlusion) 26%. All patients were operated upon after angiographic exploration (femoral catheterisation in most cases), and after cerebral CT scan. The surgical technique included general anaesthesia, systematic shunting, endarterectomy after longitudinal arteriotomy, closure without patch. The operating microscope has been used since 1985.The surgical results were studied in terms of uneventful postoperative course (87%), reversible complications (8%) and long lasting complications (5%). The long lasting complications were of local origin (1%), of neurological origin (2%), of general origin (1%). Overall the operative outcome at 6 months was: return to previous clinical state 95%, neurological sequelae 2%, death 3%. In the patients operated on for asymptomatic carotid stenosis the overall outcome was: previous clinical state 97%, death 3%. The legitimacy of carotid endarterectomy procedure is discussed in relation to some recent pertinent literature. 相似文献
18.
I. Y. Shvera A. M. Cherniavsky W. Yu. Ussov M. P. Plotnikov A. A. Sokolov V. M. Shipulin V. I. Chernov 《European journal of nuclear medicine and molecular imaging》1995,22(2):132-138
In this study we aimed to work out a quantitative prognostic index for preoperative assessment of brain technetium-99m hexamethylpropylene amine oxime (HMPAO) single-photon emission tomography (SPET) in patients referred for urgent carotid endarterectomy due to acute obstructive disease of the internal carotid artery (ICA) and neurological deficit. To this end we compared data from preoperative SPET studies with the postinterventional changes in neurological status in 20 patients (17 males, three females; mean age 53 years, SD 4 years) with acute ischaemic cerebral disorders induced by obstruction of the ICA. Carotid obstruction was diagnosed by ultrasound B-mode study. All patients underwent urgent carotid endarterectomy from the ICA. Patients were divided into two groups in accordance with the results of postoperative follow-up: group A comprised patients with significant (more than 3 points) postoperative improvement in neurological condition as quantified by the Canadian Neurological Scale (11 patients); group B consisted of patients with minimal improvement or deterioration (nine, three of whom died). All patients were studied preoperatively by99mTc-HMPAO SPET. The volume of nonperfused tissue (VS, cm3) was quantified using the Mountz technique. Hypoperfused volume (V
hypoperf, cm3) in the affected hemisphere was calculated as the total volume of voxels with99mTc-HMPAO uptake <90% of the contralateral symmetric voxels. Discriminant prognostic function was calculated by discriminant analysis as:PF = 0.072×VS + 29.46×(VS/V
hypoperf). Patients with preoperativePF values <8.20 demonstrated postoperative improvement in neurological status, while the group withPF>8.90 comprised patients who demonstrated minimal improvement or deterioration. PF values in the range 8.20–8.90 carried an indefinite prognosis. We conclude that the preoperative99mTc-HMPAO SPET can be used for the selection of patients in whom improvement in neurological status may be expected after urgent surgical correction of acute extracranial obstruction of the ICA. 相似文献
19.
颈动脉粥样硬化斑块中COX-2、mPGES-1表达及塞来昔布对其的影响作用 总被引:2,自引:1,他引:1
目的探讨兔颈动脉粥样硬化斑块中环氧化物酶-2(COX-2)、诱导型前列腺素合成酶-1(mPGES-1)的表达机制及塞来昔布对其表达的影响。方法采用32只雄性新西兰大白兔.其中正常对照组8只(A组),另24只将特制的硅橡胶圈置于兔右侧颈动脉。术后给予1%高胆固醇喂养14d,建立兔颈动脉粥样硬化性狭窄动物模型,将模型兔随机分为颈动脉狭窄无干预组(B组1、小剂量塞来昔布治疗组(15mg/kg,C组),大剂量塞来昔布治疗组(35mg/kg,D组),每组各8只。治疗4周后取双侧颈动脉并分为平等2段,分别行半定量逆转录聚合酶链反应(RT—PCR)及Western blot法测定颈动脉斑块干预后COX-2及mPGES-1的表达。结果与A组比较,B、C、D组颈动脉粥样硬化模型兔的斑块中COX-2及mPGES.1表达增高,差异具有显著性(P〈0.05);与B组比较,C、D组颈动脉斑块的C0X-2及mPGES.1表达显著下调,差异有显著性(P〈0.051。结论在颈动脉粥样硬化斑块的病理过程中炎症反应可能起着主导作用。塞来昔布干预可抑制COX-2及mPGES—1的表达,减缓颈动脉粥样硬化的进展。 相似文献
20.