消毒硫酸钡用于经皮椎体成形术的实验研究

目的探索行经皮椎体成形术时所需BaSO4粉的合适消毒方法.方法将BaSO4粉分成干热法消毒组及环氧乙烷消毒组,对其分别进行细菌培养;然后选择2种消毒法制备的BaSO4粉,将灌注剂按粉液比(g/ml)为3∶2,而粉剂中BaSO4的百分比为20%,分别进行调配.每组制备6个样本,测定其聚合时间、CT值、强度和刚度,对结果进行2组独立样本的t检验.结果 2种消毒法制备的BaSO4粉经细菌培养显示无菌,2组灌注剂间的刚度和强度有明显改变,结果差异有显著性(P ＜0.05),干热法消毒组高于环氧乙烷组;2组灌注剂的聚合时间、CT值无显著性差异(P ＞0.05).结论 2种消毒法灭菌效果满意,但干热消毒法组灌注剂材料性能优于环氧乙烷组,是经皮椎体成形术中制备BaSO4粉的较好消毒方法.     

Late changes in barium sulfate aspiration: HRCT features

Ohne Zusammenfassung     

Effects of barium concentration on the radiopacity and biomechanics of bone cement: experimental study

Purpose  This study was undertaken to evaluate the changes in the radiopacity and mechanics of polymethylmethacrylate (PMMA) bone cement with the addition of barium. Materials and methods  Barium sulfate powder was added to a PMMA bone cement with an initial 10% barium concentration. The changes in radiopacity and strength were evaluated by testing cement blocks containing four barium concentrations (10%, 20%, 30%, 40%). Radiopacity was evaluated by measuring the computed tomography (CT) values of the bone cement, and strength was evaluated by compressive, three-point bending, and impact load tests. Results  CT values increased in proportion to the barium concentration. The compressive load test showed that cement with a 40% barium concentration was significantly more fragile than cement with lower barium concentrations. The three-point bending load test showed that the cement became more fragile in proportion to the barium concentration. The impact load test showed that cement with 30% and 40% barium concentrations was significantly more fragile than cement with 10% and 20% barium concentrations. Conclusion  Radiopacity is increased and strength is reduced by adding increasing concentrations of barium powder to bone cement. The results of the present study suggest that adding barium permits the radiopacity and strength of bone cement to be adjusted in clinical practice.     

放射性覆膜金属支架制备方法的研究

目的 探索32P放射性覆膜金属支架的制备方法.方法　通过比较聚乙烯醇和聚氨酯以及不同制备工艺制作的放射性膜材料在生理盐水中的32P放射性物质的泄漏率;测量不同聚氨酯涂膜工艺和同一膜不同部分的质量和放射性计数率,测量每部分单位质量的放射性计数率,评价支架膜上放射性物质的均匀性;比较旋转滴涂法和浸涂法在支架上涂膜的不同效果.结果 聚乙烯醇中放射性物质在生理盐水中泄漏率达90%,聚氨酯能有效降低放射性物质在生理盐水中的泄漏,在其表面再涂聚氨酯涂层,泄漏率处于本底水平;不同聚氨酯膜中的放射性物质分布百分差率差异没有统计学意义(非参数检验Mann-Whitney test方法,U=10.0,P=0.602＞0.05),同一膜材料中放射性物质分布平均百分差率为11.76%;旋转滴涂法在支架上形成的膜层不均匀,出现穿孔现象,而浸涂法可形成均匀的膜层.结论 以聚氨酯作为覆膜材料,能有效减低32P放射性物质的泄漏,同时放射性物质在膜材料中的分布亦较均匀.     

大剂量人体白蛋白和硫酸镁对溶栓后脑组织的保护与促进修复作用

目的 评价rt-PA溶栓治疗联合大剂量人体白蛋白与硫酸镁延长溶栓时间窗的可能性和可靠性.方法 健康雄性成年SD大鼠40只,对血栓法建立的急性大鼠大脑中动脉栓塞(MACO)模型随机分为4组.A组:缺血3 h,rt-PA单纯溶栓(对照组,10只);B组:缺血6 h,rt-PA单纯溶栓(10只);C组:缺血6 h,rt-PA溶栓 人体白蛋白(10只);D组:缺血6 h,rt-PA溶栓 人体白蛋白 硫酸镁(10只).rt-PA(10 mg/kg)与20%人体白蛋白(2.5 g/kg)分别从大鼠股静脉缓慢注入,人体白蛋白在脑缺血3 h开始注射,1 h内完成;5%硫酸镁溶液(500 mg/kg)在脑缺血3 h和18 h自腹腔注射.于治疗前、治疗后24 h、7 d、14 d行MRI检查,在治疗14 d MRI检查结束后立即处死,行病理学检查(包括光镜、电镜和免疫组化)、激光扫描共聚焦显微镜检查.结果 ①溶栓治疗后14 d与治疗前比较,A、B、C、D 4组中脑梗死体积分别缩小5.07%、2.58%、10.18%和35.40%,以D组缩小最为明显.②4组间梗死边缘区相对脑血流量(rCBV)在4个时间段分别比较差异均有统计学意义(P均<0.05).③4组中大鼠的生存时间以D组最长,以B组最短,4组之间存活时间比较差异无统计学意义(F=0.188,P=0.904).④激光扫描共聚焦显微镜显示C组、D组脑梗死边缘区微血管轻度扩张,有少量、局限的荧光物质渗出,较B组明显减少.⑤免疫组化显示C组与D组脑梗死边缘区胶质纤维酸性蛋白(GFAP)增生活跃,与B组比较增生层较厚且密集.⑥电镜结果显示C组、D组神经元核形态基本正常,线粒体轻度肿胀.星形细胞足板轻度空泡化,较B组损害程度轻.结论 rt-PA溶栓治疗联合人体白蛋白、硫酸镁明显缩小脑梗死体积,提高脑梗死边缘区rCBV速率,促进星形细胞增生.研究表明rt-PA溶栓治疗联合大剂量人体白蛋白、硫酸镁,能有效地延长溶栓时间窗,可以延长至脑缺血 6 h内.     

Brachytherapy of a choroidal melanoma using radioactive gold grains: a long-term follow-up study.

PURPOSE: We used radioactive gold grains to treat a patient with choroidal malignant melanoma. Radioactive sources were placed into surgically constructed scleral pockets. The patient was followed up for six years after therapy to assess changes in the tumor, recurrence, and side effects. METHODS AND MATERIALS: A male patient presented with malignant melanoma arising from the choroidal membrane of the posterior pole of the left eyeball. We placed radioactive gold grains into surgically constructed scleral pockets adjacent to the tumor, arranged in a plane based on the Manchester's method. The patient was followed up for six years after treatment. RESULTS: The radiation dose was 120 Gy at the apex of the tumor, which slowly became smaller and completely disappeared at one year and 10 months after treatment. Tumor recurrence was not observed. Radiation dose at the ipsilateral lens was 280 cGy. Side effects associated with therapy were a decrease in visual acuity secondary to retinal degeneration and atrophy, but his vision was correctable with suitable glasses. In addition, the visual field of the left eye was also restricted. Mild cataracts also developed in the ipsilateral eye after treatment. CONCLUSION: Although this therapeutic method is technically difficult compared with other methods, it permits the tumor to be treated without loss of the eye. This may significantly improve the patient's quality of life.     

The adhesiometer: a simple device to measure adherence of barium sulfate to intestinal mucosa

A simple, inexpensive device assessing barium sulfate adherence to alimentary tract mucosa was tested in an animal study using pigs and dogs. Interaction of gastric, intestinal, and colonic mucosal lining with three different barium preparations was studied. In both pigs and dogs, barium adherence to gastric mucosa was significantly stronger when compared with colonic mucosa.     

Acute cerebral infarction in monkeys: an experimental study using MR imaging

Magnetic resonance (MR) imaging was performed in five monkeys with experimentally induced acute cerebral infarction to define the MR imaging features and correlate these with computed tomographic (CT) findings, laboratory analysis, and histopathologic studies. Acute infarct (2-4 hours after embolization) was generally visible on MR images but not on CT scans. CT at 24 and 48 hours did show the infarcts. In all cases the infarct was more clearly depicted with MR imaging and was visualized as an area of high signal intensity on T2-weighted images. Spectrometric nuclear MR measurements of the postmortem cerebral tissue confirmed prolongation of both T1 and T2 values similar to that calculated from MR images. At postmortem laboratory testing, the area of infarction detected with MR imaging had decreased specific gravity and increased water content, reflecting edema.