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91.
脊柱原发性肿瘤的手术治疗策略   总被引:1,自引:0,他引:1  
郭卫  唐顺  杨毅  董森 《中华骨科杂志》2006,26(12):793-797
目的 回顾性研究对脊柱原发性肿瘤患者应用多种入路实施手术治疗的效果及并发症。探讨脊柱原发性肿瘤的手术治疗策略。方法 自1998年7月至2005年7月,共收治脊柱原发性肿瘤患者135例。其中,骨髓瘤25例,神经纤维瘤、神经鞘瘤23例,巨细胞瘤17例,血管瘤15例,淋巴瘤9例,软骨肉瘤7例,骨母细胞瘤6例,嗜酸性肉芽肿6例,尤文肉瘤5例,动脉瘤样骨囊肿4例,粒细胞肉瘤4例,骨肉瘤3例,恶性纤维组织细胞瘤3例i血管内皮瘤2例,骨纤维异样增殖症2例,骨软骨瘤2例,脊索瘤2例。病变累及颈椎13例,胸椎79例,腰椎43例。出现神经系统受累者92例,其中Frankel分级A、B级9例,C、D级83例;无神经系统受累者43例。前后路联合手术切除肿瘤18例,经后路侧前方手术13例,经前路切除肿瘤73例,经后路切除肿瘤31例。结果 135例患者中,126例(93.3%)术后疼痛得到不同程度的缓解,9例术后疼痛无明显减轻。92例术前有神经系统受累的患者中,86例术后麻痹症状得到不同程度的缓解。在随访期内未见严重并发症。11例患者术后出现脑脊液漏,经应用抗生素及抬高床尾治疗后愈合。3例应急性溃疡患者,经输血及抗酸药治疗溃疡愈合。皮下气肿3例,伤口浅表感染3例,神经根损伤2例,内固定物松脱2例,瘫痪加重1例。结论 对于脊柱巨细胞瘤或软骨肉瘤等恶性肿瘤破坏单个或相邻的两个脊椎时,应采用前后路联合手术切除肿瘤。术前根据肿瘤的Tomita或WBB分期设计手术方案,合理切除肿瘤,降低术后复发率。  相似文献   
92.
Summary The Gd-DTPA-enhanced magnetic resonance findings in two patients with herniated thoracic intervertebral discs are reported. The first patient was a 56-year-old woman with a small subligamentous T6-7 disc herniation, slightly lateralized to the right. The second patient was a 51-year-old man with a central and right posterolateral disc herniation, including a large calcified fragment, at the T8-9 level. The nonenhanced MR examination revealed the presence of an extradural mass lesion in both patients, impinging upon the dural sac and compressing and displacing the spinal cord posteriorly. The lesion was slightly hypointense on both T1- and T2-weighted spin echo sequences. Following intravenous injection of Gd-DTPA in a dosage of 0.1 mmol/kg body weight, enhancement of the posterior longitudinal ligament was noted and triangular areas of contrast uptake were seen to occur in the epidural space above and below the herniated disc. At surgery, they were found to correspond to dilated and congested epidural veins.  相似文献   
93.
目的:探讨外固定器治疗不稳定型桡骨远端骨折的疗效。方法:对12例不稳定型桡骨远端骨折的患者采用改良AO外固定器治疗,术后随访5-8个月,根据骨折愈合情况和腕关节形态及功能情况,按Jakim评分结果评价治疗效果。结果:骨折愈合时间为6-8周,优良率为91%。结论:外固定器治疗不稳定型桡骨远端骨折具有良好的固定作用,能较好地防止骨折畸形愈合和保护腕关节功能。  相似文献   
94.
A phase III multicenter study was conducted in 89 patients with known intracranial vascular lesions to evaluate an extracellular gadolinium contrast agent, gadoteridol, for intracranial magnetic resonance (MR) angiography. The pre- and postcontrast MR angiograms of 82 patients were evaluated by the unblinded investigators and by two blinded readers (A and B) for visualization of lesions; arterial and venous anatomy; extent, size, and number of lesions; and disease classification. The unblinded readers indicated that lesions were visualized better on postcontrast images in the following categories: venous anatomy, 87 (81%) of 107 lesions; arterial anatomy, 43 lesions (40%); and extent or size of lesions, 38 lesions (36%). In 29 (35%) of 82 patients, the unblinded readers determined that enhanced MR angiography provided more diagnostic information than unenhanced MR angiography. The blinded readers determined that enhanced MR angiography provided more information for visualization of vascular anatomy in more than 60% of cases. The additional information provided with gadoteridol would have changed the diagnosis in nine (8%) of 107 lesions seen by the unblinded readers, 11 (12%) of 90 lesions seen by reader A, and three (3%) of 93 lesions seen by reader B. The results confirm that the use of gadoteridol improves the visualization of intracranial vascular lesions with MR angiography. The authors conclude that development of new postprocessing algorithms will improve the utility of contrast-enhanced MR angiography.  相似文献   
95.
Yucatan Pig: An Optimal Hairless Model for a True Random Cutaneous Flap   总被引:1,自引:0,他引:1  
Porcine models have been used extensively for skin flap research because of the established similarity between the cutaneous blood supply of the swine and humans. The Yucatan minipig provides an excellent model for researching the properties of random cutaneous flaps, offering several advantages over other breeds of swine. In this study, a total of 67 random cutaneous dorsal flank flaps measuring 4 × 14 cm were raised on nine Yucatan minipigs. The mean survival length (10.03 ± 1.60 cm) of the nondelayed flaps was greater than others reported in the literature. The well-defined plane between the subcutaneous tissue and the panniculus carnosus facilitated flap elevation consistently above the level of the panniculus carnosus thereby ensuring the creation of a true random cutaneous flap. Furthermore, the hairless nature of the skin, particularly beneficial in studying chemical peels, permits easy visualization and monitoring of any external skin changes. These advantages make the Yucatan minipig a more desirable alternative to other breeds of swine for use in skin flap research.  相似文献   
96.
A problem of current MRA techniques is the inability to accurately depict the vascular anatomy, particularly in areas of disturbed flow. Various reasons, such as intravoxel phase dispersion, saturation, temporal variations, and maximum intensity projection (MIP) nonlinearity, cause a wrong delineation of vessel boundaries. A phase contrast (PC)-based postprocessing operation, the phase derivative (PhD), is introduced to detect phase fluctuations indicating flow. Two-dimensional and three-dimensional angiographic reconstruction algorithms are presented. Mathematical formulas are derived to predict the effect of sampling to flow profiles and the effect on the PhD of these profiles. Numerical, phantom, and preliminary in vivo experiments demonstrate that PhD images do not suffer from phase wraps and allow a velocity dynamic range extension only limited by a differential phase change. It is also shown that PhD MIPs produce higher signal-to-noise ratios than conventional PC angiograms and give a better impression of the anatomy of (stenotic) vessels and of their diameters for both laminar and disturbed flow.  相似文献   
97.
Normal blood flow and velocity in the superior sagittal sinus were measured in 30 patients. A fast two-dimensional ungated phase-contrast (PC) pulse sequence was compared with a peripherally gated cine PC technique for velocity and flow quantitation. The same imaging parameters were used for both methods. Measured values for mean velocity and flow obtained with the two methods were compared by using regression analysis and t testing. For blood flow, the correlation coefficient was 0.976. For velocity measurements, r was 0.950. Mean flow was 285 mL/min ± 19 with the ungated PC method and 281 mL/min ± 19 with the cine PC method. The mean velocities measured with the two methods were 12.94 cm/sec ± 1.1 and 13.59 cm/sec ± 1.1, respectively. There was no significant difference (paired t test) between the methods for mean flow or velocity data. This was true even though flow in the superior sagittal sinus is moderately pulsatile, as shown with the cine PC technique. The ungated PC method provided these data in 13 seconds versus 3.5 minutes for the cine PC method.  相似文献   
98.
Prospective study of phobic anxiety and risk of Parkinson's disease.   总被引:3,自引:0,他引:3  
Anxiety disorders are common in Parkinson's disease (PD). However, the risk of PD among people with anxiety has not been examined in a prospective cohort study. We examined this relation prospectively within the Health Professionals Follow-Up Study, a cohort of US male health professionals. In 1988, anxiety was assessed using the Crown-Crisp phobic anxiety index in 35,815 men without PD, stroke, or cancer at baseline. There were 189 incident cases of PD during 12 years of follow-up. After adjusting for age, smoking, and caffeine intake, the relative risk of PD among men with the highest level of anxiety (Crown-Crisp index scores of 4 and above) was 1.5 (95% CI = 1.0-2.1; P-trend = 0.01) compared to men with the lowest level of anxiety. This positive association persisted after excluding cases of PD with onset in the first 2 years of follow-up. Use of anxiolytic medication was also associated with an elevated risk of PD (RR= 1.6; 95% CI = 0.9-3.1), but adjusting for this potential confounder did not materially affect the association between anxiety and risk of PD. Our results suggest that anxiety is a risk factor for PD. Whether this association is causal or the result of shared underlying biology remains a question.  相似文献   
99.
Small vessels in three-dimensional MR angiograms have low visibility in maximum-intensity projection images because of their low contrast. In a previous study, we had two nonlinear filters that appeared to give significant improvement in small vessel detail. In this paper, we report on a generalization of this filter that allows a more general modeling of the vessels and a more complete suppression of background. One implementation of the general filter gave a vessel mean contrast-to-noise ratio that is 2.52 and 3.51 times higher than the vessel mean contrast-to-noise ratio obtained using our previously reported maximum-minimum (max-min) filter and cross- section filter, respectively.  相似文献   
100.
Magnetic resonance imaging maps of velocity were acquired with a 1.5-T system in 10 subjects in a plane perpendicular to the main pulmonary artery. Velocity images were successively acquired with a method developed from Fourier-encoding velocity imaging (FEVI) principles with eight gradient steps and one excitation, and with two-point phase-subtraction mapping. Reconstruction in FEVI was implemented by zero-filling interpolation around the eight gradient steps and then around the four central steps. The methods were compared by using estimates of noise in velocity measurements based on the difference between the experimental map and a smooth fitted map. For the same acquisition time, FEVI with four encoding steps was more precise in velocity measurements than phase mapping. Precision was further increased by the use of eight encoding steps, but acquisition time was doubled.  相似文献   
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