激光角膜光学切除术后兔角膜上皮细胞凋亡的研究

目的 探讨激光角膜光学切除术后（ｐｈｏｔｏｒｅｆｒａｃｔｉｖｅ ｋｅｒａｔｅｃｔｏｍｙ,ＰＲＫ）伤口愈合过程中角膜上皮细胞凋亡情况。方法 对６只兔双眼分别行Ｐ．Ｒ,激光切削参数为一８．０Ｄ、１５６μｍ深,消隔直径５．６ｍｍ。将兔分别于ＰＲＫ后１ｍｏ、３ｍｏ处死,取下角膜进行冰冻切片,用的位标记检测法（ＴＵＮＥＬ法）分别检测角膜上皮细胞凋亡情况。结果 正常兔角膜可见上皮上皮浅层有少量细胞亡,ＰＲＫ后     

兔准分子激光角膜切削术后角膜血小板源性生长因子mRNA表达的变化

研究角膜上皮下混浊形成的发生机制,检测准分子激光屈光性角膜切削术后角膜上皮和基质血小板源性生长因子表达的变化。方法新西兰白兔施行ＰＲＫ后１,２,３月用裂隙灯显微镜观察ｈａｘｅ形成情况,并用原位酸分子杂交方法,检测角膜上皮和基质ＰＤＧＦ ｍＲＮＡ的表达。结果正常角膜上皮细胞有ＰＤＧＦ ｍＲＮＡ表达,基质层无表达;ＰＲＫ后角膜上皮细胞ＰＤＧＦｍＲＮＡ表达增加,术后２月表达最强,且基质中亦有轻微表达。上     

准分子激光角膜切削术前后角膜地形图对比分析

应用角膜地形图仪对比分析了９０例（１７６眼）ＰＲＫ手术前后角膜表面的形态特征及其变化。结果表明,术前角膜地形图以蝴蝶结形为多（７３．３％）;术后７９．０％为圆形或钥匙孔形,半圆形和蝶形为１８．８％中央岛形占２．２％。ＰＲＫ对散光的一次最大矫正量为－１．７５Ｄ,切削中心偏位是最佳矫正视力下降,复视和屈光度回退的重要原因。提示：ＰＲＫ术后角膜地形图的检查可准确显示角膜形态的细微变化,有利于手术设计的不断完善和效果的提高。     

准分子激光屈光性角膜切削术对角膜内皮细胞的影响

目的 探讨分析准分子激光屈光性角膜切削术（ＰＲＫ）治疗近视后对角膜内皮细胞的影响。方法 对１０１只眼ＰＲＫ术后者,用接触型镜面反光角人皮显微镜（Ｋｏｎａｎ ＳＰ－３５００型,日本）检测不同部位角膜内皮细胞,并统计分析其在不同度数范围内的平均细胞密度、细胞面积的变异系数和六角形细胞的百分率。结果 平均细胞密度在Ｃ组上降１０％,Ａ,Ｂ组的下降无统计学意义。细胞面积的变异系数及六角形细胞百分率均下降１０     

Plasminogen activator activity in tears after excimer laser photorefractive keratectomy

PURPOSE: To quantify changes of plasminogen activator activity in tear fluid during corneal re-epithelialization after excimer laser photorefractive keratectomy (PRK). METHODS: Tear samples were collected with glass capillaries from 77 eyes of 42 patients immediately before and immediately after PRK treatment and on postoperative days 3 and 5. In 20 patients, the contralateral eye was similarly sampled to serve as control. Plasminogen activator activity in the tear samples was measured by a spectrophotometric method using human plasminogen and chromogenic peptide substrate, D-valyl-L-leucyl-L-lysine-p-nitroanilide (S-2251). RESULTS: In tears of all eyes that underwent PRK, the plasminogen activator activities were lower immediately after PRK than were the preoperative values. For patient eyes with normal wound healing, tear plasminogen activator activities were significantly elevated above the preoperative level on the third postoperative day and then returned to the preoperative level by the fifth postoperative day. In contrast, tear plasminogen activator activities remained low through the third postoperative day in all (six) eyes in which haze developed after 3 to 6 months. The contralateral control eyes showed no appreciable change in plasminogen activator activity over the 5-day period. CONCLUSIONS: Plasminogen activator activity levels measured in tears of excimer laser PRK-treated eyes may serve as a predictor of wound healing. Extended low levels of plasminogen activator activity through the third postoperative day correlate with the development of corneal healing abnormalities (haze). The low plasminogen activator activity could be not only an accompanying sign but also a cause of defective corneal wound healing.     

准分子激光屈光性角膜切削术后角膜上皮愈合的影响因素

目的　探讨年龄、性别、绷带式隐形眼镜配戴、术后局部使用不同药物及手术切削深度诸因素对PRK术后角膜上皮愈合的影响。方法　对 2 5 8例实施PRK术病人 (393只眼 )进行前瞻、随机、双盲、设立安慰剂对照的临床研究。结果　不同年龄、性别、术后配戴隐形眼镜及手术切削深度诸因素对角膜上皮愈合时间无显著性差别 (P >0 0 5 )。术后使用双氯灭痛滴眼液、透明质酸钠及安慰剂组角膜上皮愈合的时间分别是 :3 78天± 1 37天、2 86天± 1 44天、3 31天± 1 5 0天 (P <0 0 5 )。结论　年龄、性别、术后配戴隐形眼镜以及手术切削深度对PRK术后角膜上皮愈合不构成影响 ,而双氯灭痛可延长角膜上皮愈合 ,透明质酸钠可促进角膜上皮的修复。     

准分子激光屈光性角膜切削术后角膜地形图岛状隆起

目的 探讨准分子激不屈光性角膜切削术（ＰＲＫ）后角膜地形图出现岛状隆起与患者各种因素的关系。方法 对连续３３３例（５９２只眼）接受ＰＲＫ治疗病人术后６个月的角膜地形图进行回顾性分析,将地形图中出现中央岛状隆起与半岛,双峰岛的资料进行比较。结果 双眼再现岛状隆起的比例高于单眼。术后１～３月岛状隆起明显且有不断增加的现象,６月时５２．６３％的岛状隆起消失。岛状隆起与角膜雾浊无关;双峰岛的隆起度较高,可     

Scanning laser polarimetry in corneal topographic changes after photorefractive keratectomy

Purpose: To examine whether, or not, corneal topographic changes after excimer laser photorefractive keratectomy (PRK) for myopia and myopic astigmatism have any influence on measurements of the retinal nerve fiber layer (NFL) with scanning laser polarimetry. Methods: Retinal NFL thicknesses were determined by scanning laser polarimetry in 17 eyes of 13 patients with myopia and myopic astigmatism before and after PRK. Total ablation depth ranged from 26 to 71 μm. We used the relative ratios for superior and inferior NFL thicknesses which were calculated by dividing the NFL values of respective regions by the nasal value. Results: The mean superior NFL ratio measured was 3.02 ± 0.92 preoperatively, and 3.00 ± 0.76 postoperatively. The mean inferior NFL ratio was 2.95±0.75 preoperatively, and 2.99±0.66 postoperatively. There was no statistically significant difference between preoperative and postoperative NFL measurements (Wilcoxon signed rank test, p > 0.05). Conclusions: Corneal topographic changes after PRK have no significant influence on NFL measurements by scanning laser polarimetry. Our results suggest that scanning laser polarimetry can be used as a reliable method for retinal NFL thickness measurements even after excimer laser PRK. This revised version was published online in July 2006 with corrections to the Cover Date.     

SPT辅助的TPRK术后角膜上皮厚度和光密度的变化及两者的相关性

目的：观察智能脉冲技术(SPT)辅助的经上皮准分子激光角膜切削术(TPRK)术后角膜上皮厚度(CET)和光密度(CD)变化,并分析两者的相关性。

方法：前瞻性研究。选取2023-02/08在新乡医学院第一附属医院眼科行SPT-TPRK手术治疗的近视及近视散光患者60例120眼,评估术前、术后1 wk,1、3 mo CET与CD的变化。

结果：纳入患者失访14例28眼,术后出现haze 3例6眼,均剔除本研究,最终纳入患者43例86眼。术后1 wk,CET高于术前(P<0.05),角膜中央0-2 mm区域CET明显增厚(P<0.05); 术后1 mo,角膜中央0-2 mm区域CET明显变薄(P<0.05); 术后3 mo,角膜中央0-2 mm区域CET基本达术前水平。术后CD值升高,术后3 mo,0-2 mm区域CET与0-2 mm区域全层CD值呈正相关(r=0.256,P<0.05),2-5 mm区域CET与2-6 mm区域前层CD值呈正相关(r=0.319,P<0.05)。

结论：角膜中央2 mm以内区域角膜上皮重塑需要3 mo时间; CET较薄的区域,术后角膜上皮重塑更快,术后早期增厚更多; 术后早期CD值较术前均增加,且部分区域CET与CD值呈正相关。     

准分子激光屈光性角膜切削术后的再治疗

目的 评价准分子激光屈光性角膜切削术（ｐｈｏｔｏｒｅｆｒａｃｔｉｖｅ ｋｅｒａｔｅｃｔｏｍｙ,ＰＲＫ）术后因屈光回退,欠矫出现的残留近视及严重角膜上皮下雾状混沌（ｈａｚｅ）而再次手术治疗的疗效及安全性。方法 采用准分子激光仪对－１．００～－１６．５０Ｄ的近视眼及近视散光患者进行治疗。ＰＲＫ术后３５例（５１只眼）患者出现残留近视及严重ｈａｚｅ。结合ＰＲＫ手术及准分子激光治疗性角膜切削术（ｐｈｏｔｏｐ     

Topography versus non-topography-guided photorefractive keratectomy with corneal cross-linking variations in keratoconus

AIM: To compare the visual results of non-topography-guided and topography-guided photorefractive keratectomy (PRK) applying sequential and simultaneous corneal cross-linking (CXL) treatment for keratoconus. METHODS: Interventional and comparative prospective study. Sixty-nine eyes (36 patients) suffering from keratoconus (stages 1 Amsler-Krumeich classification) were divided into four groups: sequential topography-guided photorefractive keratectomy with CXL, simultaneous topography-guided photorefractive keratectomy with CXL, simultaneous non-topography guided photorefractive keratectomy with CXL, and sequential non-topography guided photorefractive keratectomy with CXL. The main outcome measures were pre- and postoperative uncorrected distance visual acuity (UDVA), best corrected distance visual acuity (CDVA), manifest refraction, contrast sensitivity, and keratometry. RESULTS: All analyzed visual, contrast sensitivity, and refractive parameters showed a significant improvement in the four groups (all P<0.05). A noticeable improvement was seen in keratometry in all the groups, and a remarkable difference was observed between topography-guided groups in comparison to non-topography-guided groups (P<0.05). Interestingly, the improvement in all parameters showed a degree of stability to the end of the follow-up. CONCLUSION: The treatment priorities in all four groups are safety, efficacy, and predictability in the correction of the sphero-cylindrical errors in mild and moderate keratoconus. No significant differences among groups in the recorded objective outcomes were found.     

自体血清滴眼液对屈光性角膜切削术后角膜上皮愈合的影响

目的：研究自体血清滴眼液对屈光性角膜切削术(PRK)后角膜上皮愈合的影响。

方法：本研究共纳入20例40眼近视及近视散光患者,其中男性9例,女性11例。每例患者随机选取一眼作为研究组应用20%含自体血清的人工泪液,另一眼为对照组应用常规人工泪液。PRK 术中,40眼均于角膜表面居中放置直径8 mm的酒精储槽, 20%的酒精作用20s。术后每天观察直到角膜上皮愈合后,分别于1mo,6mo,12mo进行随访。上皮愈合时间为主要观察指标,并记录裸眼视力(UCVA),显然验光和混浊度。

结果：两组间术前小瞳检影结果无明显差异。术后1d,2d,3d,研究组平均疼痛评分均显著低于对照组(P<0.05)。术后1d,3d,研究组的平均水平和垂直上皮缺损低于对照组(P<0.05)。研究组上皮完全愈合的平均时间比对照组短约0.7d(3.15±0.366d vs 3.85±0.587d, P=0.00)。

结论：研究表明,应用自体血清滴眼液,通过加速角膜上皮愈合和减轻疼痛,从而缩短视力恢复时间,降低屈光性角膜切削术术后不适、混浊度和感染风险。     

Undercorrection after photorefractive keratectomy in Wilson's disease

A 34-year-old woman with Wilson’s disease and prominent Kayser–Fleischer rings had uncomplicated photorefractive keratectomy (PRK) in both eyes. Her preoperative refraction was −3.25 −2.50 × 180 in the right eye and −3.25 −1.50 × 180 in the left eye. The corneal topographic pattern showed symmetric bow tie with-the-rule astigmatism, and central corneal thickness was 550 μm in both eyes. Three months postoperatively, her refraction was −1.00 −1.25 × 180 in the right eye and −1.50 −1.00 × 180 in the left eye. The following enhancement surgery resulted in a stable and satisfactory refraction in 2 years. We conclude that Wilson’s disease might not be a contraindication for PRK.     

Repeated phototherapeutic keratectomy (PTK) followed by PTK with photorefractive keratectomy for anterior granular corneal dystrophy

Two preteen siblings with the anterior-stromal variant of granular corneal dystrophy type 1 underwent multiple phototherapeutic keratectomies (PTK) (due to recurrences of the dystrophy) with progressively increasing hyperopia after each procedure. The last procedure performed was an additional photorefractive keratectomy along with the PTK which led to a decrease in the hyperopia with better refractive outcomes. The addition of mitomycin C may have led to a delay in the recurrence of the dystrophy.     

Combined corneal CXL and photorefractive keratectomy for treatment of keratoconus: a review

Keratoconus and iatrogenic keratectasia are the corneal ectatic disorders occurring due to biomechanical weakening of the cornea resulting in distorted images, myopia, and irregular astigmatism. Corneal collagen cross-linking (CXL) is performed to arrest keratoconus successfully. The main aim of this review is to discuss the safety and efficacy of the adjuvant therapies, such as the combination of CXL and photorefractive keratectomy (PRK) for the treatment of corneal ectatic disorders. A comprehensive literature search was performed using PubMed, MEDLINE, and Scopus using keywords ‘collagen’ ‘keratoconus’, ‘keratectasia’, ‘collagen cross-linking’, and ‘photorefractive keratectomy’. Search results were restricted to clinical studies published in English. Corneal CXL effectively arrests the progression of keratoconus by enhancing corneal rigidity. However, functional vision is not improved by cross-linking. Combining CXL to refractive surgeries such as topography-guided PRK or transepithelial PRK is found to be a safe and effective method in providing corneal stability as well as significantly improving functional visual acuity with few minor complications. This combined technique also prevents regression of keratoconus and reduce the risk of keratectasia. CXL combined with PRK is a promising therapeutic approach in ophthalmology that can be successfully used to treat progressive keratoconus and other corneal ectatic disorders and to enhance visual acuity.     

准分子激光兔角膜切削术后细胞凋亡和增殖

目的 寻找准分子激光角膜切削术（ＰＲＫ）术后细胞凋亡和激活增殖的动态联系,评价激光去除上皮（ＰＴＫ）和机械刮除上皮（ＭＥＳ）对凋亡和增殖的影响。方法 对１８只兔按ＰＴＫ和ＭＥＳ行ＰＲＫ（－９．９０Ｄ,６．０ｍｍ直径）,术后定期用活体共聚焦显微镜观察及制作病理切片,ＴｄＴ介导ｄＵＴＰ缺口末端标记（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差别。结果 ＰＲ     

Transepithelial photorefractive keratectomy mode using SCHWIND-ESIRIS excimer laser: initial clinical results

AIM: To evaluate postoperative pain, uncorrected visual acuity (UCVA), and cornea haze value after transepithelial photorefractive keratectomy (T-PRK) performed with aspherical ablation profile using SCHWIND ESIRIS excimer laser. METHODS: Retrospective case series. Fifty-nice eyes (32 patients) with myopia associated with or without astigmatism underwent phototherapeutic keratectomy (PTK) followed by photorefractive keratectomy (PRK) which performed by Optimized Refractive Keratecomy (ORK)-CAM software based on aspherical ablation profile using SCHWIND ESIRIS excimer laser. Postoperative pain scale was measured on a questionnaire through five levels. Haze was graded by five grades, and UCVA, manifest refraction spherical equivalent (MRSE) were analyzed. RESULTS: Mean pain level was (1.37±0.613) (range: 1 to 3), the mean time picking out the soft contact lens was (6.22±1.73) days, at 3 months, UCVA was 1.0 for 40 eyes (67.8%), 0.5 for all eyes (100.0%). The UCVA was significantly less than the preoperative best spectacle corrected visual acuity (BSCVA) (t=-2.84, P=0.006), haze value was (0.27±0.25), no patients had a haze grade up to 2. Mean MRSE was (0.76±0.96) diopter(D) by 3 months. CONCLUSION: The outcomes from this study show that using the SCHWIND ESIRIS aspherical ablation profile for transepithelial PRK has a good visual result. The primary advantage is related to a spherical ablation profile, automatically considers the ablation volume of the stroma and the accurate and smooth removal of the epithelium with PTK. Additional studies are needed to determine long-term outcomes.     

准分子激光屈光性角膜切削术后角膜地形图分析

目的分析准分子激光屈光性角膜切削术（ｐｈｏｔｏｒｅｆｒａｃｔｉｖｅｋｅｒａｔｅｃｔｏｍｙ,ＰＲＫ）术后角膜切削区的形态、偏心情况和屈光的稳定性。方法对３１２例（３６６只眼）ＰＲＫ手术患者进行术后１、３和６个月的角膜地形图检查。结果术后１个月切削区中心偏离瞳孔中心的距离为０．２６６ｍｍ,双眼平均偏离瞳孔中心的方向均为鼻上侧。切削区形态平滑型占４９．５％,半环型、钥匙洞型、肾型和哑铃型占４２．９％,中心岛型占６．０％。中心岛型对术后最佳矫正视力影响较大。术后１～３个月角膜屈折力变化较大,高度近视比低度近视回退明显。结论提示ＰＲＫ术中瞄准中心问题非常重要,直接影响术后的效果,同时也应长期随访角膜地形图,进一步观察术后的稳定性。     

Delayed epithelial healing following photorefractive keratectomy with mitomycin C treatment

Purpose: To evaluate the epithelial healing following photorefractive keratectomy (PRK) with mitomycin C (MMC) 0.02%. Methods: A total of 1520 eyes of 760 patients with myopia with spherical equivalent between ?1.5 and ?8.0 dioptres underwent PRK during 2004–2008. The epithelium was removed mechanically, and laser ablation was followed by topical application of MMC (0.02%) for 20 seconds. A therapeutic contact lens (TCL), kept in 4°C, was fitted and worn until complete epithelialization. Antibiotic, steroid and diclofenac drops were instilled during the healing phase. Steroid drops were used for 6–8 weeks and gradually reduced. The results were compared with a retrospective analysis of 500 myopic eyes which underwent PRK without MMC therapy during 2002–2004. Results: In 30 MMC treated eyes (2%), epithelial healing was delayed with a stellate defect which healed after 12–14 days. Another fifteen eyes (1%) revealed loose midperipheral epithelium and complete epithelialization took 10–14 days after scraping. Two of these eyes developed recurrent erosion treated by scraping and TCL. Seven eyes (0.5%) revealed delayed healing with paracentral epithelial plaques which were scraped and complete healing took 12–14 days. No final haze was found in the MMC‐treated eyes. In comparison, only 0.8% of the eyes which had undergone PRK without MMC revealed epithelial problems. Haze was found in 8% of these eyes. A statistically significant difference was found between the rate of epithelial problems of the two groups (p ≤ 0.002). Conclusions: MMC (0.02%) applied for 20 seconds post‐PRK was found to delay epithelial wound healing up to 14 days in 3.5% of patients with myopia compared to 0.8% of PRK eyes without MMC application. Final haze was not found despite delayed epithelialization because of MMC treatment.