一种防脱出易制作义眼台的研制

目的探讨一种新型简易防脱出的义眼台的制作方法与效果。方法根据眼球摘除后的解剖特点设计义眼台大小,选择聚甲基丙烯酸甲酯和涤纶布为材料制作复合材料义眼台,并对6只家兔行眼球摘除后置入义眼台,经HE染色观察及肉眼观察术后不同时间置入物与眼周围组织的解剖关系。结果聚甲基丙烯酸甲酯部分与组织无黏连,涤纶布形成牢固黏连,周围有纤维组织长入并包绕,义眼台无脱出、移位。结论以聚甲基丙烯酸甲酯和涤纶布为材料制作复合义眼台,方法简易,效果可靠,组织相容性好,术后反应轻,值得在临床上推广使用。     

PMMA/HA-GF医用复合材料制备及性能测试

本文主要研究了无机玻璃纤维增强聚甲基丙烯酸甲酯(PMMA)/羟基磷灰石(HA)复合材料的制备及相关的性能测试,证明此复合材料性能稳定、物理机械强度高以及工艺简单,有良好的应用前景。     

超声乳化联合折叠式人工晶体植入治疗年龄相关性白内障临床观察

目的 探讨年龄相关性白内障患者实施超声乳化术后植入折叠式人工晶体的临床价值.方法 分别选取我院年龄相关性白内障超声乳化术患者植入聚甲基丙烯酸甲酯（PMMA）晶体及折叠式晶体的患者87例和93例.对两组患者术后7 d、14 d以及1个月时的视力进行统计和比较;对两组患者手术前及手术后7 d和1个月时的角膜散光情况进行统计和比较.结果 B组患者在术后7 d、14 d、1个月时视力＞0.8者分别占11.83%、18.28%以及19.35%,均明显优于A组3.45%、5.575%和13.79%,两组比较差异有统计学意义（P＜0.05）.术后7 d两组患者角膜散光分别为（1.20±0.18）D和（0.95±0.21）D,均较术前明显增加,差异有统计学意义（P＜0.05）.术后1个月,A组患者角膜散光为（0.98±0.29）D,仍明显大于术前,差异有统计学意义（P＜0.05）,而B组患者角膜散光为（0.75±0.33）D,与术前相比差别不大,无统计学意义（P＞0.05）.结论 折叠晶体的应用有利于超声乳化术联合人工晶体植入术患者术后视力的提高,如经济状况允许,建议患者选用.     

Radio-frequency plasma treatment improves the growth and attachment of endothelial cells on poly(methyl methacrylate) substrates: implications in tissue engineering

The aim of this study was to improve the biocompatibility of poly(methyl methacrylate) (PMMA) substrates for possible applications in corneal prostheses or in micro-carrier cell culture systems. PMMA substrates were exposed to radio-frequency (RF) argon and nitrogen plasmas for 5 and 10 min each. The PMMA films were examined by Fourier transform infrared (FT-IR) spectroscopy, to characterize the surface changes after plasma exposure. Plasma treatment in general was found to decrease the water contact angle of PMMA, thus increasing its hydrophilicity. There was also an associated increase in the work of adhesion of plasma-treated PMMA substrates. PMMA substrates exhibited differential properties towards endothelial cell (CPA-47) growth. The untreated PMMA surface did not support endothelial growth, compared with both polystyrene (TCPS) and plasma-treated PMMA, while plasma (PL):PMMA exhibited growth rates slightly lower than the TCPS control, as assessed by [³H]thymidine incorporation profiles. The compatibility and growth supportive properties of PL: PMMA were further confirmed by an MTT assay, which showed preserved cellular viability and mitochondrial activity of the cells. Confocal microscopic visualization of cells with fluorescence-labeled vimentin showed normal organization of the cytoskeletal fibers, indicating appropriate attachment to the substrate. Cells growing on PL:PMMA maintained their functionality, as seen from Factor VIII expression. Taken collectively, the findings of this study point out the suitability of RF plasma treatment in inducing desirable changes in PMMA substrates, so as to improve their ability to support the growth and attachment of endothelial cells.     

Retroprosthetic membrane: A complication of keratoprosthesis with broad consequences

Keratoprosthesis (KPro) devices have the remarkable ability to restore vision in patients suffering from corneal blindness who are poor candidates for traditional penetrating keratoplasty. However, eyes with KPro can experience various complications, including the development of retroprosthetic membrane (RPM). RPMs reduce visual acuity in patients due to physical obstruction of the visual axis, but studies have shown that RPM can also lead to a variety of other consequences, from melting of the corneal carrier graft to precipitating retinal detachments. Histopathologic studies have shown that RPMs are composed of elements from both the recipient and donor. The presence of myofibroblasts in RPMs imparts them with contractile properties, which can contribute to their downstream complications, including angle closure, hypotony, and retinal detachment. At present, there are limited treatments to combat the growth of RPM. Future therapies could include anti-metabolites and targeted anti-inflammatory treatments, as well as device coatings or textured device surfaces that can hinder RPM proliferation. The long-term success of KPro depends on devising an effective solution for preventing RPM growth.     

Discoloration of Provisional Restorations after Oral Rinses

Purpose: Oral rinses are widely used to promote periodontal health with provisional restorations during the interim period. The aim of this study was to compare the discoloration of provisional restoration materials with different oral rinses.Material and Methods: A total of 140 disc-shaped specimens (shade A2) (10 mm x 2 mm) were prepared from one PMMA-based (TemDent Classic^®) and three different bis-acrylic-based (Protemp II^®, Luxatemp^® and Fill-In^®) provisional restoration materials (n=7). The color values (L*, a*, and b*) of each specimen were measured before and after exposure with a colorimeter, and the color changes (∆E) were calculated according to the CIE L*a*b* system. The specimens were immersed in each of the 4 oral rinses (alcohol-containing mouthwash, chlorhexidine, benzydamine HCl, benzydamine HCl and chlorhexidine) twice a day for 2 minutes. After 2 minutes of immersion in the oral rinses, the specimens were immersed in artificial saliva. The specimens were exposed to the oral rinses and the artificial saliva for 3 weeks. Two-way ANOVA, the Bonferroni test and the paired sample t-test were used for statistical analyses (p<0.05).Results: Comparison of the discoloration from the oral rinses after immersion for three weeks revealed no significant differences (p>0.05). The lowest color change was observed in PMMA-based Temdent in all oral rinses (p<0.05). There were no significant differences between the bis-acryl composites after immersion in saliva or the mixture of benzydamine HCl and chlorhexidine and the alcohol-containing mouthwash for 3 weeks (p>0.05). After immersion in chlorhexidine, the color change values of Protemp II and Fill-in showed significant differences (p=0.018). Protemp II also showed less discoloration than the other bis-acryl composites, and this color change was statistically significant (p <0.05). For all oral rinses, the L* value decreased while b* values increased, and this color change was found to be statistically significant (p <0.05). A* values were found to be significantly higher with oral rinses (p<0.05), except Protemp II immersed in benzydamine HCl or alcohol-containing mouthwash.Conclusions: The type of the oral rinse did not affect the discoloration process. For long-term esthetic results, choosing MMA-based materials for provisional restorations appears to be more effective.     

负载抗菌药物的骨水泥的药物释放实验研究

目的 揭示负载抗菌药物的骨水泥的药物释放浓度、持续时间、药物残留程度及低于最小有效抑菌浓度的释放时间,为合理应用抗菌药物提供理论依据。方法 通过对负载盐酸万古霉素和亚胺培南西司他丁钠的骨水泥进行体外洗提实验,采用高效液相色谱法检测分析两种负载抗菌药物的骨水泥的药物释放浓度、释放持续时间和药物残留程度。结果 ①负载抗菌药物的骨水泥第一天药物释放量最大,后逐渐持平,且释放时间较长,释放浓度较低;②截止到第7周盐酸万古霉素、亚胺培南西司他丁释放量分别只占总负载量的15%、25%;③盐酸万古霉素第1周后释放浓度低于最小有效抑菌浓度,亚胺培南西司他丁钠第7周后释放浓度低于最小有效抑菌浓度。结论 载抗菌药物骨水泥存在长时间药物残留现象,是导致持续低于最小有效抑菌浓度的主要原因。此种现象不但对细菌起不到抑菌作用,而且是诱导细菌耐药性的危险因素。     

Polymethyl methacrylate intraocular lens opacification 20 years after cataract surgery: A case report in a tertiary eye hospital in Saudi Arabia

Snowflake degeneration is a slow progressive opacification of polymethyl methacrylate (PMMA) intraocular lenses (IOLs). This late postoperative complication can occur a decade or later after implantation. The deposits are composed of IOL materials that tend to aggregate centrally. There is a relative paucity of the literature on snowflake degeneration of IOLs. Symptoms can range from mild visual disturbance to significant loss of visual acuity. In cases of opacification after IOL implantation, the different diagnosis should include snowflake degeneration to prevent surgical intervention such as lens exchange or explantation unless clinically warranted. We report a case of late optical opacification of a PMMA IOL, the clinical diagnosis and treatment that increased best corrected vision.     

人工晶状体光学材料对后囊膜混浊影响的荟萃分析

目的系统评价不同光学材料人工晶状体对后囊膜混浊的影响。方法通过计算机和手工检索,获得以往发表的相关文献。按照选择标准选取合适的随机对照临床研究进行荟萃(Meta)分析。按照意向性分析原则对纳入文献的相关资料进行提取摘录,并根据Meta分析的统计学方法进行合并分析。以钕:铱铝石榴石(Nd:YAG)激光囊膜切开术为临床治疗终点,以危险差来判定预防效果,选择随机效应模型计算总的治疗效应。结果总计有14个试验纳入Meta分析。疏水性丙烯酸和聚甲基丙烯酸甲酯(PMMA)的合并危险差为-20%(95%CI为-24%～-16%),硅凝胶和PMMA的合并危险差为-8%(95%CI为-15%～-1%),水凝胶和PMMA的合并危险差为10%(05%CI为-9%～29%),硅凝胶和疏水性丙烯酸的合并危险差为4%(95%CI为-1%～8%),水凝胶和疏水性丙烯酸的合并危险差为14%(1%～26%),水凝胶和硅凝胶的合并危险差为23%(95%CI为8%～39%)。结论硅凝胶和疏水性丙烯酸人工晶状体可以预防后囊膜混浊的发生,从而减少Nd:YAG激光囊膜切开术的应用,相反水凝胶人工晶状体不能减少囊膜切开术的应用。