波前优化和波前引导准分子激光角膜切削对比

传统的准分子激光角膜切削术经过多年临床实践证实能获得较好的视力，然而传统疗法行角膜球面切削会将一般的扁平角膜变成更扁圆的轮廓，并导致球面像差。角膜非球面性的改变引起球面像差的增加，并影响夜视力和对比敏感度等视觉质量。波前优化旨在用基于总体均数的调整措施保留眼球先前的视觉像差，并优化角膜的非球面性，从而建立一个基于理想模型的个体化调整措施。波前引导测量眼球像差并行个体化切削治疗可达到更好的视觉效果。就波前优化和波前引导疗法对于球面像差的矫正效果进行综述。     

准分子激光角膜切削术与磨镶术后兔角膜基质细胞凋亡的研究

目的研究准分子激光角膜切削术(photorefractive keratectomy,PRK)和准分子激光原位角膜磨镶术(laser in situ keratomileusis,LASIK)后不同时间点角膜基质细胞凋亡的特点并探索不同手术方式、不同的矫正度数对角膜基质细胞凋亡水平的影响。方法50只新西兰纯种白兔随机分为A、B两大组,每组25只;A组兔子为PRK组,B组兔子为LASIK组;每组兔子左眼进行-4.0D激光切削,右眼进行-8.0D激光切削。分别在术后4h、24h、1w、4w和3m五个时间点处死兔子,每个时间点每组随即处死5只兔子,取兔角膜制作病理切片,行透射电镜检查,用脱氧核糖核苷酸末端转移酶介导的缺口末端标记法(terminal-deoxynucleotidyl transferase mediated dUTP nick end labeling,TUNEL)原位显示凋亡细胞,激光扫描共聚焦显微镜观察凋亡细胞形态,定量统计比较凋亡水平的差别。结果在术后4h、24hPRK组角膜基质中凋亡细胞较多,其中PRK-8.0D组的凋亡细胞数较PRK-4.0D组多,其差异有显著性意义(P<0.05);在术后4h、24h两个时间点,PRK-8.0D组与LASIK-8.0D组的角膜基质中的凋亡细胞数进行比较,两者差异有显著性意义(P<0.05);在不同的时间点,LASIK-4.0D组与LASIK-8.0D组TUNEL阳性细胞计数的比较,两者之间差异无显著性意义(P>0.05)。结论LASIK术后角膜基质细胞的凋亡水平较PRK低,凋亡程度与制瓣中的角膜损伤有关,与切削深度无明显相关;PRK术后角膜基质细胞的凋亡水平随切削深度增加而增高。     

Corneal ectasia after photorefractive keratectomy

Background Corneal ectasia after photorefractive keratectomy (PRK) has only been occasionally reported, and its incidence has not been assessed. Methods In a retrospective, non-comparative case series, incidence of corneal ectasia was evaluated in a personal consecutive 6453-case series of myopic PRK with a minimum follow-up of 18 months. Features and prognosis were evaluated in all patients with ectasia after PRK (in both personal and referred cases). Results Ectasia was detected in three eyes of two patients (patients 1 and 2) 3 years and 1 year after PRK performed elsewhere. In addition, in the personal PRK series, two eyes of two patients (patients 3 and 4) developed corneal ectasia 5 months after surgery (incidence: 0.03%). Pre-operatively, forme fruste keratoconus was present in patients 1, 3 and 4; keratoconus in the fellow eye in patient 2; pachymetry <500 micron in patients 2 and 3. In patient 1, rigid contact lenses were prescribed, and in patient 2 deep anterior lamellar keratoplasty was needed; in patients 3 and 4, low induced astigmatism resulted, requiring driving spectacles in patient 3. Conclusions PRK induced corneal ectasia in predisposed eyes, even after low myopic ablations. Forme fruste keratoconus and keratoconus in the fellow eye were the main pre-operative findings. Prognosis varies according to severity. The author has no financial or proprietary interest in any product or technique mentioned. The author has full control of all primary data, and agrees to allow Graefes Archive for Clinical and Experimental Ophthalmology to review the data upon request.     

Moria M2"90"微型角膜刀联合准分子激光角膜切削术治疗近视的临床观察

目的 探讨Moria M2"90"微型角膜刀联合准分子激光角膜切削术治疗近视的预测性、稳定性及安全性.方法 使用Moria M2微型角膜刀,90μm深度一次性切割头和德国ALLEGRETTOWAVETM Eye-Q准分子激光机对98例195眼近视病人施行矫治手术.按屈光度分为两组,Ⅰ组89眼(-6～-12.875)D,Ⅱ组106眼(-1.25～-5.875)D,术后随访3m以上.结果 术中制瓣良好,出现薄角膜瓣1例,未出现瓣碎裂、游离瓣等严重并发症.术后1d181眼(92.82%)裸眼视力达到术前最佳矫正视力.术后3m裸眼视力大于或等于最佳矫正视力的I组为84眼(97.67%),Ⅱ组为97眼(91.51%).195眼中共5眼(2.56%)出现-1.25D～-2.75D的回退.术后3m角膜地形图曲率(38.37±1.88)D和散光(-0.82±0.69)D均显著低于术前(P＜0.05);术后平均高阶像差均方根为(0.24±0.08)较术前增大.结论 Moria M2"90"微型角膜刀联合准分子激光角膜切削术治疗近视是安全和有效的.     

准分子激光原位角膜磨镶术与角膜上皮下磨镶术对中高度近视高阶像差影响的对比研究

目的 比较准分子激光原位角膜磨镶术（LASIK）和准分子激光上皮下磨镶术（LASEK）对中高度近视眼高阶像差的影响。方法 选择中高度近视行准分子激光屈光手术的连续病例27例（41眼）,其中LASIK14例（23眼）、LASEK13例（18眼）。使用Zeiss-WASCA客观像差仪在术前和术后6月测量患眼暗室自然瞳孔下的波前像差。结果 术后6月两组总高阶像差均方根（RMSh）以及3～5阶高阶像差均方根（RMS3～5）均明显高于术前,以RMS4最明显。LASIK组术后RMSh的增幅高于LASEIK组（P=0.042）。LASIK组术后Y轴彗差（Z8）与球差（Z12）明显增高（均P〈0.01）。LASEK组术后Z12明显增高（P〈0.01）。LASIK组术后Z8大于LASEK组（P=0.021）。结论 对于中高度近视矫正,LASEK对高阶像差的影响比LASIK小。     

Early phototherapeutic keratectomy in recurrent corneal erosion

AIM: To evaluate the morphological and functional outcomes of earlier excimer laser phototherapeutic keratectomy (PTK) for treatment of recurrent corneal erosion (RCE). · METHODS: A total of 25 eyes of 23 patients with RCE were enrolled in a prospective non-randomized consecutive study. In all cases, RCEs were unresponsive to conventional treatment methods. No one had experienced stromal puncture or tried contact lens previously. After complete ophthalmologic examination, central excimer laser PTK with ablation depth of 10μm and optical zones of 4-8 mm was performed. Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), spherical equivalents (SE) and refractive cylinder (RC) were compared before and after phototherapeutic keratectomy. · RESULTS: Previously 2 patients had undergone epithelial scraping. Duration of disease ranged from 2 months to 3 years prior to PTK (mean=9.3 months). The mean follow-up time was 10.1±5.5 months (4.2-19.2 months). Success rate after PTK, regarding prevention of recurrence was 96% when they were under follow-up. BCVA was also increased from 0.69±0.30 to 0.90±0.23 (P <0.001). Mean SE remained constant with values of 0.41±1.67D preoperatively and 0.35?.63D postoperatively (P =0.26). Mean RC was also improved from -1.22±0.90D preoperatively to -0.57±0.57D postoper- atively (P <0.001). · CONCLUSION: PTK using 193nm excimer laser is an effective and safe choice of treatment for a fast epithelial closure, an increase of visual acuity and alleviating symptoms in most patients with RCE in earlier course of the disease.     

准分子激光屈光性角膜切削术后兔角膜基质细胞凋亡及其防治的研究

目的：探讨准分子激光屈光性角膜切削术（photorefractive keratectomy,PRK）后凋亡机制介导的角膜创伤愈合反应对屈光度数回退和角膜雾状混浊（haze）的影响,以及局部应用锌制剂的药物效果。方法：对90只新西兰白兔行双眼PRK,将左眼作为实验眼,手术前、后分别给予A组0．1％地塞米松眼液、B组0．5％硫酸锌眼液和C组0．04％丝裂霉素眼液滴眼;右眼作为对照眼。术后定期裂隙灯下观察haze的程度,测量角膜的厚度,进行光镜和透射电镜观察,采用脱氧三磷酸尿苷缺口末端标记法行凋亡细胞检测,并进行对比性分析。结果：（1）PRK术后角膜前基质细胞出现凋亡,实验眼B组凋亡细胞最少（P＜0．01）。（2）术后角膜厚度增加,前基质细胞增多,实验眼haze和增生程度眼B组凋亡细胞最少（P＜0．01）。（3）术后角膜上皮增生,实验眼B组角膜上皮厚度最小（P＜0．01）。结论：PRK术后屈光度数回退和haze的形成是凋亡机制介导的角膜创伤愈合过程,锌制剂可阻止角膜前基质细胞凋亡,最大限度减轻反应性过度增生,有望成为临床防治haze形成和屈光度数回退的理想药物。     

准分子激光原位角膜磨镶术后角膜瓣下角膜上皮内生的治疗

目的　探讨准分子激光治疗性角膜切削术 (phototherapeutickeratectomy ,PTK)治疗准分子激光原位角膜磨镶术 (laserinsitukeratomileusis,LASIK)术后角膜瓣下角膜上皮内生的疗效。方法对LASIK术后发生角膜瓣下角膜上皮内生患者 6例 (6只眼 )行PTK ,术中重新掀开角膜瓣 ,刮除植入的角膜上皮组织 ,采用直径 7mm光斑 ,以 5～ 10个脉冲切削角膜瓣基质面和基质层表面 ,层间冲洗 ,复位角膜瓣 ,采用直径 3mm光斑 ,以 5 0～ 75个脉冲沿角膜瓣边缘进行切削。术后随访时间 5～ 12个月。结果　 5只眼表现为颞侧角膜瓣边缘下出现匍行性灰白色物质 ,局部角膜瓣边缘水肿和融解 ;1只眼表现为角膜瓣下局限性灰白色团块状物质 ,角膜瓣下基质层局部融解。全部术眼PTK术后无角膜瓣下角膜上皮内生复发 ;除 1只眼残留轻度角膜瘢痕外 ,余 5只眼角膜恢复透明 ;术后视力均达到LASIK术前最佳矫正视力。结论　采用PTK治疗LASIK术后角膜瓣下角膜上皮内生 ,不仅效果良好 ,而且可有效防止复发     

病灶切除联合多层羊膜移植治疗角膜溃疡

目的观察病灶切除联合多层羊膜移植治疗角膜溃疡的临床效果。方法对6例（6眼）细菌性角膜溃疡、3例（3眼）真菌性角膜溃疡、5例（5眼）无菌性角膜溃疡均行病灶切除联合多层羊膜移植。结果术后随访6月14例中未见排斥反应，角膜感染均在12天内得到控制，溃疡灶留下不同程度的瘢痕。结论病灶切除联合多层羊膜移植是一种治疗角膜溃疡有效的方法。     

准分子激光治疗性角膜切削术治疗角膜弥漫性火药伤

目的:探讨准分子激光治疗性角膜切削术在角膜浅层弥漫性火药伤中的应用,为角膜弥漫性火药伤提供一种新的有效的治疗方法。方法:收集1999年12月至2003年12月期间在我院就诊的25例(39只眼)角膜浅层弥漫性火药伤患者,采用准分子激光治疗性角膜切削术进行异物清除。术后观察视力、角膜上皮恢复时间、眼压、远视状态和Haze等状况。结果:该手术与常规手术相比,缩短了手术时间,一只眼激光手术过程在10min以内。一次手术即可完成绝大部分的异物剔除,手术损伤小,一般在1周内角膜上皮可以完全恢复。术后在角膜光学区基本不残留角膜斑翳,术后视力显著提高。术后10d平均视力为0.6。术后患者轻度远视38例,中度远视1例。该手术产生的并发症在术中和术后也能得到良好的控制,安全性和预测性较高。结论:准分子激光治疗性角膜切削术在角膜浅层弥漫性火药伤中是一种方便、效果好、费用低廉并值得推广的治疗方法。