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41.
目的 探讨椎动脉形态学异常对后循环TIA症状持续时间的影响。
方法 回顾性分析2015年10月-2018年3月在中国科学院大学重庆仁济医院神经内科完成头颈部DSA
或CTA的后循环TIA住院患者临床资料,根据症状持续时间分为<10 min组、10~59 min组和≥60 mi n组,
比较椎动脉形态异常各亚型在3组间的差异。通过多因素Logistic回归分析明确椎动脉形态异常与后
循环TIA症状持续时间之间的关系。
结果 共纳入237例患者,其中症状持续时间<10 min组109例(45.99%)、10~59 min组71例(29.96%)
和≥60 min组57例(24.05%)。一般临床资料的比较显示,性别、椎动脉和基底动脉狭窄率≥50%
在3组间差异具有统计学意义(P<0.05)。椎动脉形态异常中,动脉粥样硬化性椎动脉狭窄(狭窄
率1%~99%)在3组间的差异具有统计学意义(P =0.004),而一侧迂曲、双侧迂曲、一侧优势、一
侧优势合并迂曲和起源异常在3组间差异均无统计学意义;多因素Logi sti c回归分析显示椎动脉
狭窄(OR 2.500,95%CI 1.381~4.525,P =0.002)、基底动脉狭窄率≥50%(OR 12.066,95%CI
1.446~100.668,P =0.021)是TI A症状持续时间延长的独立影响因素。
结论 椎动脉狭窄和基底动脉狭窄率≥50%是影响后循环TIA症状持续时间延长的独立影响因素。  相似文献   
42.
We report the findings of spinal magnetic resonance imaging (MRI) in 2 patients who had undergone intrathecal chemotherapy and presented with the subacute onset of ascending numbness and weakness. MRI revealed a symmetric hyperintensity at the posterior columns of the spinal cord from the lower cervical region down to the conus medullaris level on T2-weighted images, and no abnormal enhancement. The imaging findings are similar to those seen in subacute combined degeneration (SCD), but the serum vitamin B(12) levels were normal in these 2 cases.  相似文献   
43.
 Resource implications of hospitalization for osteoporosis-related vertebral fracture are sparsely documented. This study utilized data abstracted from a national sample of hospitalized patients to identify characteristics of patients who are hospitalized with vertebral fracture and their patterns of resource utilization. These were compared with patterns observed for hip fracture hospitalizations. Data from the Nationwide Inpatient Sample (NIS) for 1997 were used to identify men and women age 45 years and above who had a primary diagnosis of vertebral fracture. After patients whose fractures might have been due to metastatic cancer or severe trauma were excluded, 68 901 individuals hospitalized for vertebral fracture were identified. Seventy-seven percent of these were women, most were white, 75 years and older, and had multiple comorbid diagnoses. Total charges averaged US$8000–10 000 per hospitalization and were higher in men. Mean length of stay was just under 6 days and more than 50% of discharged patients required some form of continuing care. Hospitalizations for vertebral fracture occurred at only one-fourth the rate of those for hip fracture, and created only half the hospital charges per admission. Vertebral fracture accounted for over 400 000 total hospital days and generated charges in excess of US$500 million. This resource impact is considerably higher than has been described in prior studies. Received: 25 June 2002 / Accepted: 13 August 2002 Acknowledgement This research was supported by Procter & Gamble Pharmaceuticals and Aventis.  相似文献   
44.
The estimation of vertebral fracture risk in individuals with suspected osteopenia is commonly based on measurements of lumbar spine bone density. The efficacy of vertebral size and deformity, as assessed by vertebral morphometry, in the prediction of fractures has been less studied. In an ex vivo investigation the regional relationships between vertebral size, vertebral deformity, bone density and compressive strength throughout the thoracolumbar spine were examined. In 16 vertebral columns (T1–L5) the bone mineral content (BMC) and bone mineral density (BMD) of each segment were measured using lateral projection dual-energy X-ray absorptiometry, and the vertebral cancellous density (VCD) and mid-vertebral cross-sectional area (CSA) measured using quantitative computed tomography. Vertebral body heights were determined from mid-sagittal CT scans, and vertical height ratios calculated for each segment. The failure load and failure stress of the isolated vertebral bodies were determined using a material testing device. Separate analyses were performed for the upper (T1–4), middle (T5–8) and lower (T9–12) thoracic, and lumbar (L1–5) segments. In all regions, failure load was strongly correlated with BMD (r=0.82–0.86), moderately correlated with VCD (r=0.60–0.71) and vertebral height (r=0.22–0.49), and poorly correlated with the height ratios (r=0.04–0.33). Failure stress was best predicted by BMD (r=0.73–0.78) and VCD (r=0.70–0.78) but was poorly correlated with all morphometric variables (r=0.01–0.33). The segmental correlations between BMD and VCD ranged fromr=0.49 tor=0.79. For all regions, BMD and VCD were included in the stepwise regression models for predicting failure load and failure stress. Either the mid-vertebral height or CSA were included in all the failure load models, while mid-vertebral height was included in only one of the failure stress models. The results suggest that vertebral deformity and size (as assessed by vertebral morphometry) make only a minor contribution to the prediction of vertebral strength additional to that provided by bone densitometry alone. The consistent regional relationships between variables appear to support the practice of global fracture risk assessment based on lumbar spine densitometry.  相似文献   
45.
目的 :观察椎动脉型颈椎病的高频彩色多普勒表现和血流动力学变化。方法 :应用彩色多普勒超声诊断仪 (高频探头 ,频率 7~ 10MHz)检测 138例椎动脉型颈椎病患者 (颈椎病组 )的椎动脉 (VH)内径 (D)、血流速度 (V)和血流量 (Q)、阻力指数 (RI)和搏动指数 (PI) ,观察其形态结构、并与 10 0例 (对照组 )进行对照分析。结果 :颈椎病组VA的V(除平均血流速度外 )、D ,Q ,RI,PI与对照组比较差异有显著性 (P <0 0 1)。结论 :高频彩超显示的椎动脉形态和血流参数变化为临床评价椎动脉型颈椎病治疗效果提供了有价值的依据  相似文献   
46.
目的 研究椎动脉损伤在闭合性颈椎创伤中的发病率及其与颈椎损伤机制、类型、损伤程度的相关性 ,观察椎动脉损伤后的临床症状、体征 ,探讨早期正确诊断的方法。 方法 于2 0 0 0年 8月~ 2 0 0 2年 2月间 ,利用颈部动脉磁共振血管造影 (MRA)技术 ,连续观察 4 6例闭合性颈椎创伤患者 ,结合颈椎X线、MRI、CT检查及患者的临床症状、体征综合分析。 结果 4 6例闭合性颈椎创伤中 ,12例 (2 6 % )伴椎动脉损伤。其中 7例为双侧损伤 (4例一侧未显影、一侧狭窄 ,3例双侧狭窄 ) ,5例为单侧损伤 (均为一侧狭窄 ) ;10例椎动脉损伤患者无任何症状 ,2例出现眩晕、恶心呕吐、面部麻木、偏盲等症状。椎动脉损伤与屈曲型损伤及颈椎严重不稳定相关 (P <0 .0 5 ) ,与小关节绞锁、横突孔骨折及脊髓完全性损伤明显相关 (P <0 .0 1)。 结论 椎动脉损伤是闭合性颈椎创伤的较常见并发症 ,其临床症状体征缺乏特异性。颈椎创伤中的颈椎严重不稳定、屈曲型损伤、伴有脊髓完全性损伤、小关节绞锁和 (或 )横突孔骨折应高度怀疑椎动脉损伤。临床医师应对此类损伤有较高的警惕性 ,常规进行颈部动脉MRA检查是最有效的早期正确辅助诊断方法。  相似文献   
47.
Modic changes following lumbar disc herniation   总被引:4,自引:3,他引:1  
Only a small proportion (20%) of patients with LBP can be diagnosed based on a patho-anatomical entity. Therefore, the identification of relevant subgroups, preferably on a patoanatomical basis, is strongly needed. Modic changes have been described by several authors as being closely linked with LBP. The aims of this study were to describe the prevalence of Modic changes, their development as well as their association to LBP, previous disc contour, and surgery in patients with previous severe sciatica. This is a longitudinal cohort study where the patients were recruited from an RCT comparing two active conservative treatments, the 181 patients, who at baseline had radicular pain in or below the knee; all underwent a physical examination and MRI. MRI’s, pain history and physical examination of 166 patients were obtained at follow-up 14 months later. The prevalence of Modic changes type 1 increased from 9% at baseline to 29% at follow-up. At that time, a strong association between Modic changes and non-specific LBP was noted. Apparently, Modic changes type 1 was more strongly associated with non-specific lumbar pain than Modic changes type 2. The development of new Modic changes was closely related to the level of a previous disc herniation. A lumbar disc herniation is a strong risk factor for developing Modic changes (especially type 1) during the following year. Furthermore, Modic changes are strongly associated with LBP.  相似文献   
48.
The aims of this study were to ascertain vertebral deformity prevalence in elderly men and women and to describe the association between bone mineral density (BMD) at the lumbar spine and femoral neck, severity of spinal degenerative disease and vertebral deformity prevalence. We performed standardized spinal radiographs in a random sample of 300 elderly men and women participating in the Dubbo Osteoporosis Epidemiology Study, a population-based study of fracture risk factors. Radiographs were read independently by masked observers for the prevalence of vertebral deformity and severity of osteophytosis. BMD was measured by dual-energy X-ray absorptiometry. The prevalence of vertebral deformities was critically dependent on the criterion used. The less strict criteria seemed to overestimate deformities at either end of the spine region analysed. However, irrespective of the criterion used, prevalence of deformity was higher in men than in women (25% vs 20% for the 3 SD criterion, 17% vs 12% for the 4 SD criterion and 27% vs 25% for the 25% criterion). Femoral neck BMD was more strongly associated with vertebral deformities than spinal BMD for the 25% criterion (OR/SD change in BMD 1.39 (p=0.02) vs 1.20 (p=0.19)), 3 SD criterion (OR/SD change in BMD 1.45 (p=0.01) vs 1.10 (p=0.34)) and 4 SD criterion (OR/SD change in BMD 1.98 (p=0.0002) vs 1.68 (p=0.008)). BMD was also more strongly associated with biconcave deformities than either wedge or crush deformities and more so in men than in women. Severity of spinal osteophytosis was not associated with vertebral deformity. In conclusion, femoral neck BMD is at least equivalent to the lumbar spine BMD in strength of association with prevalent vertebral fractures. Spinal osteophytosis falsely elevates BMD without a concomitant decrease in fracture risk, indicating that any interpretation of spinal BMD needs to be adjusted for osteophytosis. These findings support the use of femoral neck bone densitometry in older men and women. Moreover, these data indicate that current criteria for radiological assessment of vertebral deformity are sufficiently loose to include a substantial proportion of non-fractures in the elderly, with important implications for the design of clinical trials. However, irrespective of the criterion used, vertebral deformities in men are at least as common, if not more so, than in women, suggesting that vertebral osteoporotic fractures are overlooked in men.  相似文献   
49.
Percutaneous transluminal angioplasty (PTA) of the vertebral artery was performed with an autoperfusion balloon catheter in five patients. There were no complications in the form of embolic episodes or neurological deficits due to brain ischaemia during inflation. In critical cases with insufficient collateral circulation during temporary occlusion, the use of an autoperfusion balloon catheter may expand the indications for PTA in patients with ischaemic cerebrovascular disease.  相似文献   
50.
Summary The effects of calcitonin gene-related peptide (CGRP) on canine cerebral arteries and on vertebral blood flow were investigated in-vivo and in-vitro and the findings compared with the effects of vasoactive intestinal peptide (VIP) and substance P. Administration of CGRP into the vertebral artery caused a dose-dependent and long-lasting increase in blood flow. The in-vivo vasodilatory effects of substance P and VIP were short-lasting. CGRP (0.1 to 100 nmol/l) elicited a concentration-dependent relaxation of the isolated middle cerebral and basilar arteries when the tissues were precontracted by exposure to prostaglandin F2 (PGF2). This effect was not antagonized by propranolol, atropine, tetrodotoxin, (N-Ac-Tyr1, D-Phe2)-growth hormone-releasing factor(1–29)-NH2 or (D-Pro2, D-Trp7,9) substance P. CGRP also reduced concentration-dependently the contraction of cerebral arteries induced by KCl or 9,11-epithio-11,12-metano-thromboxane A2 (STXA2). Mechanical removal of the endothelium did not abolish the vasodilatory response to CGRP. In PGF2-contracted canine cerebral arteries, VIP (0.1 to 100 nmol/l) was less potent a vasodilator than CGRP. At low concentrations (0.01 to 1 nmol/l) substance P elicited a rapid and short-lasting relaxation, and in the absence of endothelium this relaxation disappeared. These findings are clear evidence that CGRP modulates vascular tone.  相似文献   
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