| Cataract is the first cause of blindness in our country. As the statistic evidence showed, 450 thousand cases underwent operations in 2001, approximate 265.5 thousand (59% ) of which had intraocular lens (IOL) implantations, and approximate 45 thousand of which were treated by phacoemulsification. Therefore, most of IOLs used in our country were poly (methyl methacrylate). The biocompatibility of PMMA IOL is worse than other soft foldable IOLs. In 1990s, heparin surface-modified poly (methyl methacrylate) (HSM-PMMA) IOL was produced by Pharmacia company. The clinical observation indicated it had better biocompatibility. Then, experts started trying other way to modify the IOL. Yuan et al.(Chinese) prepared F-heparin surface modified IOLd; Kim K grafted PEG on the PMMA IOL surface; Eloy R treated PMMA IOL with CF4 plasma. All the methods could reduce the cellular deposits or synechia of the iris by changing the hydrophilicity or surfacial enegy of IOLs. The results of cell culture and animal experiments showed that the surface modification was an effective way to improve the biocompatibility of IOL. However, there were 3 ways to modify the IOLs: 1) hydrophilized modification, 2) hydrophobizedmodification, 3) without hydrophilicity changing.Hydrophilized and hydrophobized modification were the two complete opposite ways. We were confused why the different ophthalmologists chose the opposite ways and all of their results showed some advantage of the modigied IOLs. We studied all the documents, and tried to clear the relationship between the biomaterials and clinical complications.The IOL can induce pathophysiological reactions through the stimulation of adjacent tissues. Through the stimulation of lens epithelial cells (LECs), the anterior surface of the IOL typically causes anterior capsular opacification (ACO), which can be more severe when the IOL contains hydrophobic biomaterials rather than their hydrophilic counterparts. In addition, stimulation of the iris by the IOL can induce cellular deposits, such as macrophage adhesion, aqueous flare, synechia of the iris, etc. Recently, clinical observations have indicated that hydrophobic IOLs stimulate the iris more than hydrophilic IOLs]. The posterior surface of the IOL is only able to induce posterior capsular opacification (PCO), through the stimulation of immigratory LECs from the peripheral anterior capsule. PCO is a serious complication, which can reduce visual acuity. The induction of PCO has been reported to be less severe when using hydrophobic IOLs rather than hydrophilic IOLs.Therefore, the problem was cleared now: the 2 kinds of IOLs have their own advantage. How can prepare a new kind of IOL to have both advantages of these 2 kinds? The novel idea is the new IOL would have a hydrophilic anterior surface and a hydrophobic posterior surface.Part IThe surface modification of poly methyl methacrylate intraocular lens with a-Allyl Glucoside and the attachment and NO production of macrophage on the a-Allyl glucoside-modified PMMA intraocular lensObjective To study a method for improving the biocompatibility of the intraocular lens (IOL) and reducing the cell attachment. And to investigate the attachment and NO ( nitric oxide ) production of macrophage on hydrophilic a-Allyl glucoside(a-AG)-modified PMMA IOLs.Methods The methods were achieved by modifying the a-Allyl glucoside on the poly methyl methacrylate (PMMA) 1OL surface by plasma-induced in site polymerization. The IOLs were indivived into 2 groups:the control group and the treated groupa, in which the treatment times were 0 min ( the control), 30min, 60min, 90min and 1 20min.( 8 IOLs of each group)The surfaces of control and treatment IOLs were characterized by contact angle estimation and ESCA techniques. The resolution, diopter and anti- fatigue of loops were determined by physical and optical methods. Cell attachment on these surfaces were examined by light microscopy. The production of NO by macrophage on the IOLs surfaces was measured by an automated colorimetric a...
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