角膜基质环植入术治疗圆锥角膜的临床疗效

目的：评估角膜基质环植入术治疗圆锥角膜的临床疗效。

方法：这一回顾性对照干预性研究对56例87眼圆锥角膜患者进行手术后随访。所有患者完善眼科检查,评估视力。15眼使用飞秒激光制备角膜隧道。72眼使用机械的方法制备角膜隧道。

结果：所有患者术前裸眼视力1.38±0.37。术后4mo裸眼视力达到0.58±0.32。术后16mo达到0.48±0.30。

结论：角膜基质环植入术是治疗圆锥角膜的有效方法。有效的干预与理想的术后视力相关。飞秒激光角膜隧道制备和机械方法一样安全。     

角膜基质环植入术的研究进展

角膜基质环(intrastromal corneal ring，ICR)植入术，是一种矫正低、中度近视的角膜屈光手术。它与PRK，LASIK不同，不需切削角膜中央光学区组织，手术后患者不会出现任何异物感。而且具有可预测性、安全性、稳定性及可逆性和可调换性的优点。     

基质内角膜环植入术的研究

基质内角膜环是一种新型的角膜屈光矫正装置，一种非闭合的聚甲基丙烯酸甲酯环，用于矫正近视眼。本文综介绍了基质蚋角膜环植入术的手术方法、手术效果以及与手术有关的角膜变化。     

MyoRing植入术治疗圆锥角膜的疗效观察

目的：比较MyoRing植入前后圆锥角膜(KCN)患者角膜前后表面散光和全屈光散光。

方法：历史队列研究。比较植入360度全环植入物(MyoRing)的KCN患者的术前和术后全屈光、角膜前后表面散光,术后3、6、9、12 mo连续随访四次。

结果：共纳入KCN患者79例85眼,其中男43例,女36例,平均年龄29±7.41(17-48)岁。随访期间,全屈光散光、角膜前后表面散光呈减少趋势。MyoRing植入后12 mo,总屈光散光测量值显著下降2.09 D(4.27±3.15 vs 2.18±1.63 D,P<0.001)。此外,术后测量显示,角膜前表面和后表面散光分别改善约3.20 D和0.59 D\〖6.40±1.90 vs 3.20±1.75 D(P<0.001)和1.30±0.55 vs 0.71±0.35(P<0.001)\〗

结论：MyoRing植入可显著改善散光参数,包括全屈光散光以及角膜前后表面散光。     

圆锥角膜基质环植入手术前后人工晶状体度数的比较

目的:评估圆锥角膜基质环(keraring 355°)(ICRS)植入术前术后3mo人工晶状体(IOL)度数的计算和生物学特征.方法:队列研究.收集18例(19眼)圆锥角膜接受角膜基质环植入术患者术前及术后3mo数据.分析裸眼视力(UCVA), 最佳矫正视力(BCVA),屈光度,人工晶体度数计算公式,眼轴长度(AL)和角膜曲率.结果:患者平均年龄为29.58±0.6y.裸眼视力由0.84(0.35) LogMAR 显著提高到0.43 (0.31) LogMAR (P<0.001).3mo后,最佳矫正视力和眼轴长度无明显变化.球镜度数,柱镜度数和等效球镜(SE)均显著提高 (P<0.001).另一方面,角膜曲率1(K1)和角膜曲率2(K2)显著下降.3mo后, SRK/II (P<0.001), Hoffer Q (P<0.001) and Holladay I (P<0.001)发生显著变化.结论:角膜基质环植入术后,视力,屈光率和角膜曲率均有所提高,此外,人工晶状体计算公式度数明显改变.然而,角膜基质环植入术过程没有过度干预眼轴长,但降低角膜曲率值使得人工晶状体度数计算更加精确,所有公式得出同一晶状体度数.     

圆锥角膜治疗进展

圆锥角膜是一种以角膜扩张为特征,病因不明的双侧进行性角膜病变。角膜接触镜是轻中度圆锥角膜最常用的矫正方法。角膜表层镜片术、深板层角膜移植术、角膜基质环植入术、角膜交联疗法及穿透性角膜移植术是临床上常用的手术治疗方法。     

角膜基质环植入术治疗近视眼的临床研究进展

角膜基质环植入术是一种即将兴起新的矫正近视眼的屈光手术,其区别于当今流行的屈光手术如PK、PRK和LASIK手术的主要特点在于该手术具有不损伤角膜结构的完整性和手术操作方式的可逆性,尽管目前其仍处于临床实验阶段,但据其所取得初步临床效果,已令人感到鼓舞,为此,本就目前角膜基质环植入手术有关临床方面的研究进展加以综述。     

基质内角膜环植入术的最新研究进展

基质内角膜环植入术是一种新型的有膜屈光手术。本文综合介绍了ＩＣＲＩ对角膜非球面性的影响,生物相容性的组织学检查,屈光矫正效果和术后反应的研究,以及对圆锥角膜的治疗尝试。     

圆锥角膜的治疗进展

本文通过对圆锥角膜治疗方法的综述,为临床医生选择合适的治疗方法做出参考。通过数据库对“圆锥角膜”“隐形眼镜”“角膜胶原交联”“Intacs(角膜环)”“角膜成形术”“基因治疗”“不规则散光”等关键词进行搜索,并根据相关文献对圆锥角膜的治疗方法进行综述。眼镜和隐形眼镜可用于圆锥角膜早期,而疾病晚期时可采用前弹力层移植术、穿透性角膜成形术(PK)和深层前板层角膜成形术(DALK)、传导性角膜成形术和基因治疗。此外,角膜胶原交联可以阻止圆锥角膜进展,角膜基质环植入术(ICRS)通过使变形角膜变平,减少屈光不正以达到治疗目的。总得来说,眼科诊断技术和治疗方法的发展可以减缓圆锥角膜进展,从而减少晚期角膜圆锥患者对角膜移植的需要。选择恰当的圆锥角膜治疗方案可以帮助患者改善视力和预防失明。     

Evaluation of intrastromal corneal ring segments for treatment of keratoconus with a mechanical implantation technique

Purpose:

To evaluate the clinical outcomes of intrastromal corneal ring segment (ICRS) implantation in patients with keratoconus using a mechanical implantation technique.

Materials and Methods:

Thirty eyes of 17 patients with keratoconus were enrolled. ICRSs (Keraring) were implanted after dissection of the tunnel using Tunc''s specially designed dissector under suction. A complete ophthalmic examination was performed, including uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), spherical equivalent, keratometric readings, inferosuperior asymmetry index (ISAI), and ultrasound pachymetry. All 3-, 6-, and 12-month follow-ups were completed, and statistical analysis was performed.

Results:

The mean preoperative UDVA for all eyes was 1.36 ± 0.64 logMAR. At 12 months, the mean UDVA was 0.51 ± 0.28 logMAR (P = 0.001), and the mean preoperative CDVA was 0.57 ± 0.29 logMAR, which improved to 0.23 ± 0.18 (P = 0.001) at 1 year. There was a significant reduction in spherical equivalent refractive error from –6.42 ± 4.69 diopters (D) preoperatively to –1.26 ± 1.45 D (P = 0.001) at 1 year. In the same period, the mean K-readings improved from 49.38 ± 3.72 D to 44.43 ± 3.13 D (P = 0.001), and the mean ISAI improved from 7.92 ± 3.12 to 4.21 ± 1.96 (P = 0.003). No significant changes in mean central corneal thickness were observed postoperatively. There were no major complications during and or after surgery.

Conclusion:

ICRS implantation using a unique mechanical dissection technique is a safe and effective treatment for keratoconus. All parameters improved by the 1-year follow-up.     

Evaluation of intrastromal corneal ring segments for treatment of post-LASIK ectasia patients with a mechanical implantation technique

Aim:

To evaluate the clinical outcomes of Keraring segment implantation in patients with post- laser-assisted in situ keratomileusis (LASIK) ectasia, using a mechanical implantation technique.

Materials and Methods:

Twelve eyes of 10 patients with post-LASIK ectasia were enrolled. Intracorneal ring segments (ICRS) were implanted after dissection of the tunnel using Tunc''s specially designed dissector under suction. A complete ophthalmic examination was performed, including uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), spherical equivalent, keratometric (K) readings, inferosuperior asymmetry index (ISAI), and ultrasound pachymetry. All 3, 6, and 12-month follow-ups were completed, and statistical analysis was performed.

Results:

The mean preoperative UDVA for all eyes was 1.28 ± 0.59 logMAR. At 12 months, the mean UDVA was 0.36 ± 0.19 logarithm of the Minimum Angle of Resolution (logMAR) (P=0.002), and the mean preoperative CDVA was 0.58 ± 0.3 logMAR, which improved to 0.15 ± 0.12 (P=0.002) at 1 year. There was a significant reduction in cylindrical refractive and spherical equivalent refractive error from –5.29 ± 2.47 diopters (D) and –5.54 ± 5.04 D preoperatively to –1.47 ± 0.71 D and –0.74 ± 1.07 D (P=0.001, P=0.002), respectively, at 1 year. In the same period, the mean K- readings improved from 47.93 ± 4.84 D to 40.87 ± 2.36 D (P=0.002), and the mean ISAI improved from 5.34 ± 3.05 to 2.37 ± 1.68 (P=0.003). No significant changes in mean central corneal thickness were observed postoperatively. There were no major complications during or after surgery.

Conclusion:

ICRS implantation using a unique mechanical dissection technique is a safe and effective treatment for post-LASIK ectasia. All parameters showed improvement at 1-year follow-up.     

Clinical effectiveness of intrastromal corneal ring segments among keratoconus patients

AIM: To evaluate the clinical effectiveness of intrastromal corneal ring segments (ICRS) among the patients suffering from keratoconus. METHODS: A retrospective and non-comparative interventional design had been utilized on the basis of postoperative follow-up among 56 keratoconus patients. Visual acuity was significantly assessed during complete ophthalmic examination of the patients. The femtosecond laser had been used to create the corneal tunnels in 15 eyes; whereas, the corneal tunnels were created in 72 eyes mechanically. RESULTS: The ranges and standard deviations had been used to obtain results. It had been revealed through ophthalmic assessment that the mean preoperative uncorrected visual acuity observed was 1.38±0.37 logarithm of Minimal Angle of Resolution. Moreover, a significant improvement was observed postoperatively in visual acuity by 0.58±0.32 during the 4th month. The improvement was also witnessed in the 16th month by 0.48±0.30. CONCLUSION: The implantation of ICRS is an efficient and effective surgical intervention for the treatment of keratoconus. Thus, identified intervention seems to be associated with appropriate visual outcomes and safety after the development of femtosecond as well as mechanical tunnels.     

Clinical outcomes after intrastromal corneal ring segments reoperation in keratoconus patients

AIM:To evaluate the clinical outcomes after Ferrara intrastromal corneal ring segments (ICRS) reoperation in patients with keratoconus.RESULTS: The mean follow-up time after the reoperation was 30.5±9.7 months. The mean UCVA improved from 20/300 to 20/80 (P=0.005); the mean BCVA improved from 20/160 to 20/50 (P=0.0002), the mean keratometry reduced from 49.33±4.19D to 46.16±3.90D (P=0.0001), the mean pachymetry at the thinnest point increased from 450±42.9mm to 469±40.8mm (P=0.0001). The asphericity increased from -0.84±0.74 to -0.35±0.81 (P=0.15) and the spherical equivalent reduced from -4.64±4.87D to -3.04±3.45D (P=0.137). The changes in the asphericity and spherical equivalent were not statistically significant.CONCLUSION: Ferrara ICRS implantation showed to be a reversible and readjustable surgical procedure for keratoconus treatment. Good outcomes can be obtained even after removal, addition, reposition or exchange of ICRS.     

Intrastromal corneal ring segments for management of keratoconus

Keratoconus is a progressive corneal ectasia, which can be managed both by conservative measures like glasses or contact lenses in non-progressive cases or surgical procedures like collagen crosslinking (CXL) with or without adjuvant measures like intrastromal corneal rings segments (ICRS) or topography guided ablation. Various kinds of ICRS are available to the surgeon, but it is most essential to be able to plan the implantation of the ring to optimize outcomes.

Aims:

The aim of this study is to evaluate the visual outcome and progression in patients of keratoconus implanted with ICRS.

Materials and Methods:

Two different types of ICRS-Intacs (Addition Technology) and Kerarings (Mediphacos Inc.) were implanted in 2 different cohorts of patients and were followed-up to evaluate the outcome of the procedure. All patients underwent a complete ocular examination including best spectacle corrected visual acuity, slit lamp examination fundus examination, corneal topography and pachymetry. The ICRS implantation is done with CXL to stop the progression of the disease. Improvement in uncorrected visual acuity (UCVA), best spectacle corrected visual acuity and topographic changes were analyzed.

Results:

A significant improvement in keratometry and vision was seen in both groups.

Conclusion:

ICRS have been found to reduce corneal irregularity and flatten keratometry with improvement in UCVA and best corrected visual acuity.     

基质内角膜环植入术的实验研究

目的　观察基质内角膜环（ＩＣＲ） 植入术在动物实验中的安全性。方法　选择３０ 只新西兰纯种兔６０ 眼随机植入不同厚度（０１９ ～０４１ ｍ ｍ ） 的基质内角膜环,分别于术前及术后１ｄ ,１ ｗ ｋ ,１ 、３ 、６ ｍｏ 作裂隙灯检查,术前及术后１ ｗｋ ,１ ｍ ｏ 作眼压检查。结果　所有各眼的角膜切口均愈合良好,ＩＣＲ 在角膜基质中表现出良好的组织相容性,未见明显的ＩＣＲ 表面角膜上皮糜烂及ＩＣＲ 被挤出现象发生。术后所有各眼中央角膜均保持透明。术前、术后眼压比较无显著性差异。周边部的角膜浑浊及切口处的新生血管生长是常见的二个并发症。结论　ＩＣＲ 植入术是一种简单、安全的角膜屈光手术     

Spontaneous breakage of intracorneal ring segments (ICRS) 8 years after implantation

We present a case of spontaneous in situ breakage of intracorneal ring segments (ICRSs) 8?years after their implantation in a patient with keratoconus. The patient presented to our clinic with a red and painful right eye that had not improved despite topical steroids and antibiotics. The decision was made to explant the broken ICRSs from the cornea and send them for laboratory analyses, by which manufacturer defects were excluded. It is noteworthy that corneal curvature re-steepening was observed 4?months after ICRS removal despite the performance of crosslinking (CXL) 1?year prior to ICRS implantation.     

Complications of intrastromal corneal ring segment implantation using a femtosecond laser for channel creation: a survey of 850 eyes with keratoconus

Acta Ophthalmol. 2011: 89: 54–57

Abstract.

Purpose: To report complications after the implantation of intrastromal corneal ring segments (Keraring; Mediphacos, Belo Horizonte, Brazil) in keratoconic eyes using a femtosecond laser (IntraLase; Advanced Medical Optics, Santa Ana, California, USA) for channel creation. Methods: Retrospective chart review of 531 patients (850 eyes) who underwent Keraring insertion using a femtosecond laser for channel creation. Intraoperative and postoperative complications were recorded. Results: Intraoperatively, there were 22 (2.7%) cases of incomplete channel formation. The rest of the intraoperative complications were galvo lag error (system malfunction) [five eyes (0.6%)], endothelial perforation [five eyes (0.6%)] and incorrect entry of the channel [two eyes (0.2%)]. Postoperatively, there were 11 (1.3%) cases of segment migration, two (0.2%) cases of corneal melting and one (0.1%) case of mild infection. The overall complication rate was 5.7% (49 cases out of 850 eyes). Conclusion: In this study, intracorneal ring segment implantation using a femtosecond laser for channel creation was related to a number of complications. The most common complications were incomplete channel creation (intraoperatively) and segment migration (postoperatively).