经角膜上皮激光角膜切削术治疗近视及近视散光术后1年的临床疗效观察

目的评价经角膜上皮的激光角膜切削术（TPRK）治疗近视及近视散光的临床疗效。方法前瞻性研究。入选2013年5月至2014年6月在安徽医科大学第二附属医院屈光中心行TPRK治疗的65例（127只眼）患者。术后1~3 d对患者行疼痛评分问卷调查。记录术前术后视力、术后残余屈光度及术后角膜上皮下雾状混浊（Haze）程度的变化。术后1年对患者行满意度问卷调查。手术前后视力对比采用配对t检验。结果术后第1天疼痛程度平均为（2.29±0.71）（1~3）。术后1年UCVA达到1.0为65只眼（98.5%）,所有眼均达到0.8（100%）。术后1年UCVA优于术前BCVA（t=6.11,P﹤0.001）,Haze值为（0.08±0.20）。术后1年平均等效球镜为（-0.25±0.57）D。结论 TPRK治疗近视合并散光疗效明确,为安全、有效、精确的角膜屈光手术方式,能有效改善患者视力及生活质量。     

Trans-PRK与PRK临床对比分析研究

目的：为了减轻患者准分子激光角膜切削术术后的疼痛,提高角膜上皮的愈合速度,现将激光切削与酒精剥除角膜上皮进行对比分析,旨在检测经角膜上皮的准分子激光角膜表层切削术(Trans-PRK)与准分子激光角膜表面切削术(PRK)相比的可预测性、安全性、有效性。方法60例需行PRK手术的患者全部纳入临床观察研究,所有患者均为右眼行酒精去上皮的PRK手术,左眼行激光去上皮的Trans-PRK手术,术前未与患者特别说明两种方式的区别,术后第1、3、7天通过询问患者双眼疼痛感、异物感、畏光流泪等不适感觉,对患者双眼自我感觉进行对比分析,然后术后1、3 d行裂隙灯下观察,术后7 d、1、3、6个月行裂隙灯下观察、角膜染色等方式检查术眼角膜上皮修复情况,然后分析两种手术方式在屈光矫正的可预测性、安全性、有效性。结果 Trans-PRK和PRK两种手术方式,患者在术后1 d双眼不适的自我感觉方面无明显差异,3 d时行PRK的术眼较行Trans-PRK的术眼不适感明显(60例,38例主诉右眼较左眼不适感明显),术后3 d观察行Trans-PRK术眼的角膜上皮修复较行PRK术眼恢复快(60例左眼角膜上皮3 d均恢复,可以取下角膜接触镜,46例右眼角膜上皮3 d恢复,余下14例更换角膜接触镜后,延迟1 d,于术后第4天取下角膜接触镜)。患者术后3 d的裸眼视力,左眼视力明显高于右眼视力。结论 Trans-PRK手术方式较传统20%酒精去上皮的PRK手术更加简便易行,不但利于临床医生掌握操作,也能加速术后角膜创面的恢复,减轻患者术后的痛苦,加快患者术后视力的恢复,虽然观察数量为60例,为期6个月,但仍能证实较传统PRK手术的优越性。     

应用高透氧性角膜接触镜在准分子激光角膜切削术后的病原学分析

目的针对准分子激光屈光性角膜切削术(PRK)后所使用的绷带式高透氧性角膜接触镜的病原学进行分析。方法对接受PRK手术的50例(100只眼)患者,手术前取结膜囊分泌物进行细菌学培养。术后给予术眼配戴高透氧性绷带式角膜接触镜,术后第6~8天摘除角膜接触镜,将角膜接触镜进行细菌学检测,并同时再次取结膜囊分泌物进行细菌学培养。并将接触镜培养阳性的患者与培养阴性的患者分组对比,分析两组间矫正视力、眼压、角膜厚度等相关影响因素的差异性。结果 100片角膜接触镜中,3片(3%)细菌学检测结果呈阳性,均为表皮葡萄球菌。所有患者术前、术后结膜囊均未监测到细菌,术后均未见眼部感染表现。阳性组和阴性组间,泪液分泌量存在差异,可能与培养阳性有相关。结论 PRK术后使用的高透氧性绷带式角膜接触镜具有发生细菌污染的可能,尤其对于泪液分泌量较少的患者,其角膜接触镜发生感染机率较高。手术前后合理用药可有效控制接触镜中细菌的繁殖。     

Pigment dispersion syndrome diagnosed after photorefractive keratectomy—A case report

Pigment dispersion syndrome predominantly affects young myopes. It is not uncommon for such patients to seek refractive surgery. It may also be encountered after an uneventful refractive surgery. We report a case of a young myopic male who presented with bilateral pigment dispersion syndrome 9 months after an uneventful photorefractive keratectomy. A meticulous ocular examination is the cornerstone of a successful refractive surgery. Through this report, we highlight the need for gonioscopy to be included as a routine examination in screening for refractive surgery.     

Photorefractive Composite Based on a Monolithic Polymer

A new class of photorefractive (PR) composite based on a fully functionalized polymer with high phase‐stability is reported. The polymer containing non‐linear optical (NLO) chromophores and charge‐transporting carbazole moieties is synthesized by a polymer‐analogous reaction. The polymer is doped with plasticizer, NLO dye, and sensitizer to fabricate the PR composite. The NLO dye is the same as the NLO chromophore moiety in the polymer side chain. The PR performance of the composite is evaluated by degenerated four‐wave mixing and two‐beam coupling measurements. A diffraction efficiency of 30% at a relatively low applied electric field of 45 V μm^?1 is achieved. Despite a high concentration of NLO dye, the composites show good stability for a long period without phase separation.     

Quickly Updatable Hologram Images Using Poly(N-vinyl Carbazole) (PVCz) Photorefractive Polymer Composite

Quickly updatable hologram images using photorefractive (PR) polymer composite based on poly(N-vinyl carbazole) (PVCz) is presented. PVCz is one of the pioneer materials of photoconductive polymers. PR polymer composite consists of 44 wt % of PVCz, 35 wt % of 4-azacycloheptylbenzylidene-malonitrile (7-DCST) as a nonlinear optical dye, 20 wt % of carbazolylethylpropionate (CzEPA) as a photoconductive plasticizer and 1 wt % of 2,4,7-trinitro-9-fluorenone (TNF) as a sensitizer. PR composite gives high diffraction efficiency of 68% at E = 45 V μm⁻¹. Response speed of optical diffraction is the key parameter for real-time 3D holographic display. The key parameter for obtaining quickly updatable holographic images is to control the glass transition temperature lower enough to enhance chromophore orientation. Object image of the reflected coin surface recorded with reference beam at 532 nm (green beam) in the PR polymer composite is simultaneously reconstructed using a red probe beam at 642 nm. Instead of using a coin object, an object image produced by a computer was displayed on a spatial light modulator (SLM) and used for the hologram. The reflected object beam from an SLM was interfered with a reference beam on PR polymer composite to record a hologram and simultaneously reconstructed by a red probe beam.     

LASIK与LASEK矫正近视的对比研究

[目的]对比分析准分子激光角膜原位磨镶术（LASIK）和准分子激光上皮下角膜磨镶术（LASEK）术后安全性、有效性.[方法]选择高度近视72例127眼,分为LASEK治疗组38例（68眼）和LASIK治疗组34例（59眼）,检查并比较两组患者术后裸眼视力（UCVA）、屈光度、角膜上皮下雾状混浊（haze） 程度和并发症.[结果]术后1周时, LASEK 组UCVA 明显低于LASIK组（P〈 0.05）,但术后1个月、3 个月、6个月时两组UCVA 比较,差异均无显著性（P〉0.05）.术后1周及1个月、3个月时,两组屈光度比较,差异无显著性（P〉0.05）.术后6个月时,两组中有部分患者出现屈光回退现象,LASEK 组回退幅度较LASIK组明显,两组屈光度比较,差异有显著性（P〈0.05）.全部患者手术进行顺利,术中无严重的并发症发生.LASIK 组未出现Haze, 而LASEK组术后可见少量haze, 无2级以上Haze出现.[结论]LASIK和LASEK在矫正高度近视方面均具有良好的有效性好,安全性,但前者较后者视力恢复快,而远期疗效和安全性不及后者.     

PRK术中应用低浓度丝裂霉素治疗低中度近视

目的：评价PRK术中应用低浓度(0.02g/L)丝裂霉素(PRK+LMMC)30s治疗低、中度近视眼术后疗效。

方法：选取我院接受屈光性角膜切削术(PRK)治疗的30例57眼低、中度近视患者,术中应用0.02g/L的MMC 30s,将术后6mo的随访结果与同期接受准分子激光原位角膜磨镶术(LASIK)治疗的疗效进行比较。

结果：术后6mo,PRK+LMMC治疗组等值球镜屈光度0.210D、等值球镜屈光度在±0.50D范围内的发生率71.9%、裸眼视力≥1.0者77.2%,平均最佳矫正视力1.19±0.18; LASIK治疗组等值球镜屈光度-0.017D,等值球镜屈光度在±0.50D范围内的发生率70.1%,裸眼视力≥1.0者72.7%,平均最佳矫正视力1.16±0.19,两组比较差异均无统计学意义(P>0.05)。术后6mo,PRK+LMMC治疗组没有出现超过1级的haze,所有眼最佳矫正视力均好于术前。LASIK治疗组1眼因角膜上皮植入使最佳矫正视力较术前下降3行,其余眼最佳矫正视力均好于术前。

结论：PRK术中应用0.02g/L的MMC 30s治疗低、中度近视同LASIK具有同样的视力结果,避免了LASIK瓣的并发症,不失为一个可取的手术程序。     

Optimization of Photorefractivity Based on Poly(N‐vinylcarbazole) Composites: An Approach from the Perspectives of Chemistry and Physics

The optimization of photorefractivity (PR) based on a poly(N‐vinylcarbazole) (PVCz) composite devise is proposed from the perspectives of chemistry and physics. The device's PR chemistry (dependence of PVCz's molecular weight) and physics (dependence of grating periodicity and laser wavelength) are studied. Increasing the molecular weight of PVCz from 23 000 to 1 270 000 g mol^?1 significantly increases diffraction efficiency, grating build‐up speed (inverse of response time), and sensitivity. Narrowing grating period from 5.1 to 1.1 μm gives faster response time and larger optical gain. Shorter wavelength of writing laser from 633 to 532 nm provides higher diffraction efficiency, faster response time, and larger optical gain.

     

角膜胶原交联术及其联合屈光手术治疗圆锥角膜研究进展

自90 年代末以来,角膜胶原交联术（CXL）已成为治疗圆锥角膜的首选治疗方式。如今,CXL与屈 光矫正术的结合（CXL plus）受到更多关注。CXL plus在阻止圆锥角膜进展的同时,也为患者的视觉 康复提供了新途径。现有多种联合方案且均已得到不同程度的研究,包括准分子激光屈光性角膜消 融术、准分子激光治疗性角膜消融术、角膜基质内环植入及有晶状体眼人工晶状体植入等。本综述 旨在介绍目前常用的CXL及CXL plus的研究现状,并讨论这些方案的潜力。