Rose K RGP对圆锥角膜矫正视力影响的初步观察

目的:初步观察Rose K硬性透氧性角膜接触镜(Rose K RGP)对圆锥角膜矫正视力的影响。方法:为经角膜地形图确诊为圆锥角膜的12例20眼验配Rose K RGP。该组病例球镜屈光度范围-1.00～-21.50DS;柱镜屈光度范围-1.25～-8.75DC。排除配戴禁忌证,经RGP规范验配程序(高度数球镜患者采用快速睫状肌麻痹检影,次日复查屈光度)和Rose K RGP试戴片戴镜验光,确定RGP镜片参数。配发镜片后,教育戴镜者依照规范操作方法及程序配戴和护理镜片。随访时间5～14mo。我们采用自身前后对照方法进行最佳矫正视力的对比研究。结果:该组病例中14眼(70%)为三点接触配适形态,5眼(25%)为顶点离开的配适形态,1眼(5%)为可接受的顶点接触配适形态。全部病例均能通过配戴Rose K RGP获得较框架眼镜更好的矫正视力(平均框架视力0.6±0.03,平均RGP视力0.9±0.05)。随访期内无严重并发症发生。结论:在角膜地形图指导下,圆锥角膜患者验配Rose K RGP容易达到比较理想的配适形态,获得较满意的矫正视力,矫正效果理想。     

硬性透气性角膜接触镜矫正圆锥角膜疗效分析

目的 探讨硬性透气性角膜接触镜(RGP)矫正圆锥角膜的临床疗效及安全性.方法 对2004～2010年视光门诊应用RGP矫正的63例圆锥角膜患者,男41例,女22例.年龄16-35岁,平均年龄(24.6±7.81)岁.双眼57例,单眼6例.对散光度明显增大,框架眼镜矫正视力下降的患者应用电脑验光仪、角膜地形图仪、角膜内皮镜检测,筛查圆锥角膜病.对确诊及疑似圆锥角膜患者根据角膜圆锥程度采用普通RGP镜或特殊设计圆锥角膜镜进行矫正.测量RGP矫正视力及戴镜验光.应用SPSS13.0统计软件对框架眼镜矫正视力、RGP矫正视力、及配戴RGP前后球镜度、散光度进行统计学分析,P＜0.05为有统计学意义.结果 (1)本组病例框架眼镜矫正视力均值:0.56±0.29,RGP矫正视力均值:0.93±0.20,(t=-14.627,P=0.000),RGP矫正视力明显优于框架矫正视力.(2)配戴RGP前散光均值:(-4.16±2.19)DC,配戴RGP后散光均值:(-0.77±1.2)DC,(t=-14.585,P=0.000),配戴RGP散光度明显降低与配镜前比较差异显著有统计学意义.(3)其中22只眼平均观察3.5年,其中1只眼角膜混浊加重,施板层角膜移植术.其余21只眼角膜散光度降低,有统计学意义.角膜厚度、角膜曲率变化差异无统计学意义.结论 RGP矫正圆锥角膜不规则散光明显提高矫正视力,改善视觉质量,在一定程度上延缓圆锥角膜病的进展.     

硬性透气性角膜接触镜矫治屈光不正的临床观察

目的:观察硬性透气性角膜接触镜矫治屈光不正的效果、使用安全程度及舒适度.方法:对38例(76眼)来我院验配RGPCL的患者,根据其屈光度、角膜曲率和配适情况选择合适的镜片.定期观察其配戴RGPCL的矫正视力、适应性及舒适度.结果:配戴RGPCL可以获得良好的矫正视力,尤其对高度近视、散光及圆锥角膜的矫正效果明显优于框架眼镜(P=O.005).RGP镜片屈光度均低于框架眼镜屈光度.戴镜1mo后均感觉较为舒适,镜片中心位置及活动度好,未见有严重角结膜并发症.结论:RGPCL对屈光不正有良好的矫正效果,明显优于框架镜,且安全有效容易被接受.     

硬性透氧性角膜接触镜治疗高度与特殊类型屈光不正

目的：探讨采用硬性透氧性角膜接触镜( rigid gas permeable,RGP)治疗成人高度与特殊类型屈光不正的临床效果及安全性。
　　方法：回顾性分析2010-01/2012-12在本院眼科中心验配RGP的110例185眼患者的临床资料,根据患者的屈光不正类型分为高度近视散光组49例92眼、圆锥角膜组36例64眼、特殊屈光不正组25例29眼,观察三组患者行RGP配戴后不同时间的视力、常规框架镜的矫正视力差异及不良反应情况。
　　结果：配戴 RGP 后即刻,高度近视散光组的矫正视力为4.94±0.16,圆锥角膜组4.98±0.15,特殊屈光不正组4.87±0.19,均显著优于配戴框架镜时的矫正视力(4.86±0.23,4.79±0.22,4.61±0.27),且差异均具有统计学意义(P<0.05)。配戴RGP后第3,6 mo三组患者的视力复查结果显示优于配戴框架镜时(P<0.05)。视散光组、圆锥角膜组、特殊屈光不正组配戴RGP后的视力分布明显优于配戴框架镜时(P<0.05)。
　　结论：RGP配戴矫正成人高度与特殊类型屈光不正较普通框架镜均具有显著的效果,不会增加干燥、异物感、易疲劳等不良反应的发生率,值得临床应用推广。     

球面透气性硬性角膜接触镜矫正高度角膜散光

目的评价球面透气性硬性角膜接触镜（rigid gas permeable contact lens，RGP）矫正高度角膜散光（≥3．00 D）时的有效性、稳定性和患者耐受性。方法选择高度角膜散光患者41例55眼，经角膜曲率检查、电脑验光、检影验光、综合验光仪验光，确认为总散光与角膜散光基本一致者，进行试戴片配适评估、戴片验光，给予配戴球面RGP。定期回访，记录矫正视力、镜片配适及配戴情况。结果RGP最佳矫正视力：30眼（占54.5％）高于框架镜，22眼（占40.0％）等于框架镜，3眼（占5．5％）低于框架镜。患者均获得稳定配适。随访1—65个月（平均40．5个月），3例（4眼）患者因不能适应镜片的异物感而停戴。其余38例（51眼）仍坚持配戴，并对该矫正方法满意。结论应用球面RGP矫正高度角膜散光，可获得良好配适和满意的视力矫正效果。多数患者能够坚持长期配戴。     

RGP对早期圆锥角膜患者屈光状态改变的分析

目的：分析RGP与框架镜对圆锥角膜患者屈光系统的影响及RGP对不同类别(性别、年龄不同)患者的影响,进而探讨RGP的作用。

方法：确诊为早期圆锥角膜患者46例,其中27例为双眼,19例为单眼,共73眼。对患者配戴框架镜及RGP时,视力矫正幅度的差异进行比较; 对配戴RGP前、后分别进行的2次验光的差值进行比较,并针对RGP对不同性别、年龄人群矫正视力的改变值进行统计学分析,对其中44例患者69眼的角膜厚度与正常人进行比较。

结果：配戴框架镜与配戴RGP的患者视力矫正幅度的差异有统计学意义(P<0.05)。患者配戴RGP前2次验光结果的差值与配戴RGP时2次验光结果的差值相比较,差异有统计学意义(P<0.05)。男性与女性矫正视力幅度差异有统计学意义(P<0.05)。25岁以下与大于等于25岁患者矫正视力幅度差异无统计学意义(P>0.05)。确诊患者角膜厚490μm。

结论：(1)配戴RGP患者矫正视力优于配戴框架镜患者。(2)配戴RGP时验光误差小于不戴镜验光。(3)RGP矫正视力男性优于女性。(4)RGP矫正视力与年龄差异无关。(5)圆锥角膜患者角膜中央区厚度变薄。     

非球面高透氧性硬性透气性角膜接触镜矫正特殊类型屈光不正的临床评价

目的:评价非球面高透氧性硬性透气性角膜接触镜(rig idgas-permeable contactlens,RGPCL)矫正特殊类型屈光不正的临床疗效及安全性。方法:收集2009-03/2009-12验配非球面高透氧性RGPCL的特殊屈光不正的患者53例99眼,分为:(1)高度近视组6眼;(2)高度散光8眼;(3)屈光参差组15眼;(4)高度近视+高度散光组(近视≥-6.00D或散光≥-2.00D)10眼;(5)高度近视+高度散光+屈光参差组8眼;(6)圆锥角膜组(确诊为圆锥角膜的患者)48眼;(7)混合散光2眼;(8)特殊类型屈光不正组(角膜屈光手术后)2眼。观察验配RGPCL后的矫正视力,并与框架镜的矫正视力比较。定期复诊,记录矫正视力、镜片配适及配戴情况。结果:本组病例戴框架镜(试镜架)的等效球镜度数为(-8.10±5.38)D,而RGP度数为(-6.50±4.13)D,两者差异有显著性(t=-7.499,P<0.01)。戴RGPCL后的视力矫正视力(LOGMAR)为(0.02±0.09),低于戴框架镜的最佳矫正视力(0.14±0.20)。两者具有统计学差异(t=7.03,P<0.01);戴镜3~6mo后,出现10眼角膜上皮擦伤,3眼镜片丢失。结论:应用非球面RGP可矫正高度近视散光、圆锥角膜及各种原因引起的高度屈光不正,其矫正视力明显优于框架眼镜,并有较高的舒适度和安全性,无明显的并发症发生。     

硬性透气性角膜接触镜对超高度近视的矫治作用

目的探讨硬性透气性角膜接触镜对超高度近视的矫治作用。方法对40例74眼,等效球镜值≥-10.00D的超高度近视者,配戴硬性透气性角膜接触镜。观察其配适情况和视力矫正效果。结果配戴RGP后最佳矫正视力平均达到了1.04±0.30,≥1.0视力者占64.86%,≥0.8视力者占85.14%(P<0.01)。结论超高度近视配戴RGP后能达到最佳的视觉矫正效果,对于高度散光和高屈光参差者,也能达到较理想的矫正视力。     

儿童配戴RGP镜片的临床分析

目的探讨儿童配戴RGP镜片的有效性和安全性。方法3年来观察配戴RGP镜片48例(94眼)7-12岁屈光不正儿童。分析配戴前检查、验光、基弧设计,正确配戴健康教育及护理。观察配适、视力矫正效果和并发症。结果94眼屈光类型以复性近视散光居多,占59．5％。屈光度≥±10．00D的极重度屈光不正占25．5％。94眼框架眼镜矫正视力与首次配戴RGP镜片矫正视力对比,RGP镜片矫正视力明显优于框架眼镜(P<0．01)。94眼戴框架眼镜被诊断为弱视者有44眼。首次配戴RGP镜片矫正视力≥0．8者32眼(76．2％),其中有19眼(45．2％)配戴RGP镜片矫正视力在1．0以上,否定了弱视诊断。一次性配戴成功占89．6％。在3个月内丢失镜片占12．8％。无角膜上皮擦伤或角膜溃疡等并发症。结论RGP镜片矫正视力良好,特别是高度屈光不正,高度散光,高度屈光参差能获得较好矫正视力,对屈光不正性弱视有更好的矫正。儿童适合配戴RGP镜片,安全有效。安全性关键在于镜片良好的配适及配戴教育。镜片基弧的设计,配适的评估与成人有差异。要重视复诊时的体征,适当调整基弧至关重要。     

配戴硬性透气性角膜接触镜治疗难治性弱视

目的：研究硬性透气性角膜接触镜（ RGP）在难治性弱视患配戴硬性透气性角膜接触镜治疗难治性弱视 者中的治疗效果。 方法：对98例98眼难治性弱视患者,根据自愿原则给以配戴RGP镜及继续配戴框架眼镜,并继续予以正规弱视训练6mo,观察两组的弱视治疗效果（当天,1,3,6mo矫正视力）及RGP组并发症。 结果：RGP组同期矫正视力较框架眼镜组提高明显;治疗6mo后,RGP组治疗效果明显优于框架眼镜组,且RGP组无严重并发症发生。 结论：对于治疗难治性弱视患者,配戴RGP比配戴框架眼镜能获得更好的矫正视力,是一种安全、有效的方法。     

Use of SoftPerm contact lenses when rigid gas permeable lenses fail.

PURPOSE: We evaluated the performance of the SoftPerm contact lens (Wesley Jessen) in patients with irregular astigmatism, usually due to keratoconus or after penetrating keratoplasty (PK), who were unable to befitwith, or intolerant of, rigid gas permeable (RGP) contact lenses. METHODS: A retrospective study of patients fit with SoftPerm lenses in the Cornea Department at Wills Eye Hospital between March 1985 and March 2000 was performed. RESULTS: Thirty-five cases were reviewed, with follow-up available in 33 cases. Most of the eyes had irregular astigmatism secondary to keratoconus (22/35,62.9%) or PK (10/35,28.6%) and had failed a trial of RGP lenses. The mean logMAR visual acuity with SoftPerm lenses was 0.13+/-0.18 (range -0.12 to 0.6). In 25 cases in which comparison with glasses or RGP lenses was possible, SoftPerm lenses provided better visual acuity than glasses in 17/25 cases (68%) with a mean difference of -0.24 (P = 0.001, paired t-test); visual acuity with SoftPerm lenses was better than RGP visual acuity in 13/25 cases (52%), with a mean difference of -0.06 (P = 0.07, paired t-test). Complications included broken lenses (16/33,48.5%), giant papillary conjunctivitis (GPC) (9/33, 27.3%), and peripheral corneal neovascularization (9/33, 27.3%). The GPC and peripheral corneal neovascularization were often delayed in presentation. The major subjective complaint was discomfort (13/33, 39.4%). At the last follow-up, the SoftPerm lens was still in use in 22/33 cases (66.7%). Discomfort was the most common reason for discontinuation. The mean duration of lens wear was 52.5+/-31.7 months, range 3 to 110 months. CONCLUSIONS: The SoftPerm lens can provide satisfactory visual correction in many cases of irregular astigmatism with RGP failure. However, problems such as frequent breakage, GPC, peripheral corneal neovascularization, and discomfort necessitate close follow-up.     

Management of pellucid marginal corneal degeneration with rigid gas permeable contact lenses.

PURPOSE: To study the clinical performance of rigid gas permeable contact lenses (RGPCL) in patients with pellucid marginal corneal degeneration (PMCD). METHODS: This retrospective study consisted of 15 patients with clinical PMCD, confirmed by videokeratography (TMS-1, Computed Anatomy, Inc., New York, NY). Information collected from the medical records included patient demographic data, uncorrected visual acuity, refraction, best-corrected spectacle visual acuity, and topographic details, including kerotometry. Twenty-seven of 30 eyes were subjected to several contact lens trials using polymethylmethacrylate (PMMA) contact lenses, using a systematic and consistent approach. After successful contact lens trials, data regarding number of trials, trial time, final contact lens choice parameters, and best-corrected contact lens visual acuity were noted for each patient. During follow-up, visual acuity with RGPCLs, lens fit, and average wearing time were noted. RESULTS: Fifteen patients (30 eyes) with typically inferiorly located pellucid marginal corneal degeneration were included in this study. There were 12 men and 3 women, with a mean age of 39.73 years. Twenty-seven eyes of 15 patients were identified as subjects for multiple contact lens trials, and 24 (88.8%) eyes were successfully fitted with RGPCLs. Best-corrected visual acuity of 6/12 or better with spectacles was achieved in 14 (46.66%) eyes. The average astigmatism was -8.56D, and a majority of the patients with PMCD who were in the contact lens trial had an against-the-rule astigmatism (63.3%). The mean trial time for attempted eyes (i.e., patients with PMCD who successfully underwent the contact lens trials) was 77.7 minutes, and the number of trials required to finalize the choice of contact lenses ranged between 2 and 7. The median base curve for RGP lenses was 7.57, and median diameter was 10.00 mm. Best-corrected visual acuity of 6/12 or better with the final contact lens was achieved in 95.4% of the subjects. After an average follow-up of 22.91 months, one patient was lost to follow-up, and 2 eyes required discontinuation of the contact lenses. The average wearing time among the contact lens wearers at their last follow-up visits was 9.58 hours. Final visual acuity of 6/12 or better was observed in 77.3% of eyes at the end of 22.91 months. CONCLUSION: Large-diameter RGPCLs are better tolerated and lead to significant improvement in visual acuity in inferior PMCD.     

透气硬性角膜接触镜在角膜屈光手术后的应用

目的 观察透气硬性角膜接触镜(Rigid Gas-permeableContactlenses,RGP)在角膜屈光手术后矫正视力、改善视觉症状的效果.方法 眼科视光门诊中做过近视性角膜屈光手术的患者7例1 1只眼,经常规检查后,予验配多种设计的RGP,记录戴镜前的裸眼视力、框架镜最佳矫正视力和戴RGP的最佳矫正视力.记录部分患者戴RGP前后的波前像差.随访过程中记录配戴情况及并发症.结果 该组患者需要三种设计的RGP镜片:圆锥角膜RGP、逆几何RGP和大直径非球面RGP.戴RGP前裸眼视力在0.03～0.4者7只眼,0.8～1.0者4只眼.戴RGP前的框架镜最佳矫正视力在0.2～0.5者5只眼,0.7～1.0者6只眼.戴RGP的最佳矫正视力在0.7～0.9者4只眼,1.0者7只眼.配戴RGP后的球差、彗差和三叶草差分别较配戴前降低88.7%、92.9%和18.9%.全部患者的视觉症状在配戴RGP后均改善.角膜上皮染色是最常见的并发症,主要是圆锥角膜的锥顶部上皮磨损染色.平均随访21.5月,全部患者能够坚持日间配戴.结论 角膜屈光手术后配戴特殊设计的RGP可以提高视力,改善视觉质量.未见严重地角膜接触镜相关的并发症.

Abstract：

Objective To evaluate the efficacy of specially designed rigid gas-permeable contact lenses (RGP) in visual correction and visual symptom control after corneal refractive surgery. Methods Eleven eyes of 7 cases after myopic corneal refractive surgery from optometry clinic were fitted with RGP in different designs after routine eye checks. Uncorrected visual acuity (UCVA), best spectacle corrected visual acuity (BSCVA) before RGP fitting and best contact lens corrected visual acuity (BCLCVA) after RGP fitting were recorded. Wave front aberrations of some patients before and after RGP fitting were measured. Fitting state and complications were recorded at follow-ups. Results Three kinds of lens design were applied: keratoconic design, reverse geometry design and aspheric design with larger diameter. BCLCVA was much higher than UCVA and BSCVA. Spherical aberration, coma and trefoil were reduced by 88.7%, 92.9% and 18.9% respectively after RGP fitting. Visual symptoms of all patients after RGP fitting were improved. The main complication was corneal staining of iatrogenic keratoconus. All patients can tolerate wearing RGP in the day time after an average follow-up of 21.5 months. Conclusions Specially designed RGP fitted after corneal refractive surgery can raise the best corrected visual acuity and improve the quality of vision. No serious complications related to RGPwearing are observed.     

A summary of the findings from the Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study. CLEK Study Group.

BACKGROUND: This summary of the Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study includes the study design and results to date. METHODS: The CLEK Study is a longitudinal, observational study of 1,209 patients with keratoconus. The study's main outcome measures are corneal scarring, visual acuity, corneal curvature, and quality of life. RESULTS: These patients' mean age at baseline was 39.3 +/- 10.9 years, and they had moderate to severe keratoconus. Ninety-five percent of the patients had steep keratometric readings of at least 45 D, and 78% had best-corrected visual acuity of 20/40 or better in both eyes. Sixty-five percent of the patients wore rigid gas-permeable contact lenses in both eyes, and most of those (73%) reported that their lenses were comfortable. Most rigid gas-permeable contact lens wearers were fitted with apical touch (88%). Fifty-three percent had corneal scarring in one or both eyes, and corneal scarring was associated with corneal staining, contact lens wear, age, the presence of a Fleischer's ring, and a steeper cornea. Corneal scarring was associated with decreased high- and low-contrast visual acuity. CONCLUSIONS: These results characterize keratoconus patients as rigid gas-permeable contact lens wearers with moderately steep corneas. Corneal scarring is associated with decreased vision in keratoconus.     

Visual performance of rigid gas permeable contact lenses in patients with corneal opacity.

PURPOSE: To evaluate the visual performance of rigid gas permeable (RGP) contact lenses in patients with nebular and nebulo-macular corneal opacity and correlate the improvement in visual acuity with other visual parameters. METHODS: In a prospective study, visual performance of RGP contact lenses was evaluated in eyes with corneal opacity involving the pupillary area. The baseline visual acuity and other visual parameters with glasses were compared with those recorded with RGP contact lenses. The visual functions evaluated were visual acuity, contrast sensitivity, glare acuity, and mesopic vision. Binocular status with RGP contact lenses was assessed. All patients were followed up for 3 months. RESULTS: Twenty-eight eyes (26 patients) with nebular or nebulo-macular corneal opacity were included in this study. All eyes (100%) achieved significantly better visual performance with RGP contact lenses than with glasses (P< 0.0020). Visual acuity of 6/9 or better was achieved in 50% of patients with RGP contact lenses compared to none with glasses. RGP contact lenses improved the visual acuity by 0.27 decimals over the baseline value with glasses, butthe improvement for mesopic vision and glare acuity was significantly lower at 0.15 and 0.06 decimals respectively. Similarly, contrast sensitivity did not improve to the same extent as visual acuity. Stereopsis was present only in patients with best corrected visual acuity of 6/9 or better with RGP lenses. CONCLUSION: RGP contact lenses improved the visual acuity and other visual performance in patients with reduced vision due to nebular or nebulo-macular corneal opacity. However, contrast sensitivity, glare acuity, and mesopic vision did not improve to the same extent as visual acuity.     

Visual rehabilitation and outcomes for ectasia after corneal refractive surgery

PURPOSE: To analyze the visual outcomes and method of final visual correction in eyes with corneal ectasia after laser in situ keratomileusis (LASIK) or photorefractive keratectomy (PRK). SETTING: Emory University Department of Ophthalmology and Emory Vision, Atlanta, Georgia, USA. METHODS: This retrospective review comprised 74 eyes of 45 patients with corneal ectasia after LASIK (72 eyes) or PRK (2 eyes). Outcomes included postoperative uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), best corrected visual acuity (BCVA), and refraction; method of final visual correction; and time to rigid gas-permeable (RGP) contact lens failure. RESULTS: Corneal ectasia developed a mean of 19.2 months after surgery. Postoperatively, the mean UCVA was 20/400 and the mean BSCVA before ectasia management was 20/108. After ectasia management, the mean BCVA was 20/37 and the final BCVA was 20/40 or better in 78% of eyes. Final visual correction was achieved with RGP lenses in 77% of eyes, spectacles in 9%, collagen crosslinking in 3%, intracorneal ring segments in 1%, and penetrating keratoplasty (PKP) in 8%. Two eyes with intracorneal ring segments required segment explantation and subsequent PKP. One eye that had PKP had a graft-rejection episode; there were no graft failures. Two eyes (3%) did not require a visual device to improve visual acuity. The mean time for successful RGP lens wear was 24.8 months; 80% of cases initially managed with RGP lenses were successful with this form of treatment. CONCLUSIONS: The majority of eyes developing postoperative corneal ectasia achieved functional visual acuity with RGP lens wear and did not require further intervention. Penetrating keratoplasty can usually be postponed or avoided by alternative methods of visual rehabilitation; however, PKP, when necessary, can provide good visual outcomes.     

Contact lens fitting difficulties following refractive surgery for high myopia.

PURPOSE: To describe the clinical and optical problems encountered in contact lens fitting following refractive surgery for high myopia. METHODS: Following refractive surgery for high myopia (greater than -10.00 D) we corrected residual refractive errors with contact lenses in the four eyes of two patients. The first patient had undergone bilateral laser in situ keratomileusis (LASIK),with two subsequent LASIK retreatments in the left eye. Ten months later she was fit with rigid gas permeable (RGP) lenses in both eyes. The second patient had undergone a clear lens extraction in the right eye and radial keratotomy followed by photorefractive keratectomy(PRK) in the left eye. She was fit with toric soft lenses six years postoperatively. RESULTS: Final visual acuity obtained with contact lenses was 20/25-20/20 in all eyes. The first patient required significant minus lens power compensation. Furthermore, the RGP lens in the left eye was slightly decentered due to corneal irregularity induced by LASIK. The second patient had regular corneal surfaces and was successfully fit with daily wear toric soft lenses despite the 2.75 D of residual astigmatism in the left eye. CONCLUSIONS: Following refractive surgery for high myopia a proportion of patients will remain undercorrected. In these patients the alterations in corneal architecture that ensue make contact lens fitting more challenging. Patients with regular astigmatism may be fitted successfully with toric soft lenses. Patients with corneal irregularities should be fit with RGP lenses.     

Current perspectives in the management of keratoconus with contact lenses

Our aim is to review current and significant articles on contact lens wear in keratoconus patients. A comprehensive literature search of PubMed was performed for the following topics on contact lens wear in keratoconus patients: (1) characteristics of contact lens wearers, (2) safety and efficacy, (3) complications, (4) fitting techniques, (5) contact lens wear after procedures/surgeries, (6) patient satisfaction. A total of 104 studies were finally selected and reviewed. Gas permeable (GP) lens wear provided significantly better vision than glasses. Special cone design lenses had better patient comfort levels though there was no difference in best corrected visual acuity among the GP lenses. Soft lenses showed good efficacy for the treatment of mild-to-moderate keratoconus with newer designs improving visual performance such as customised hydrogel and novel pinhole lenses. Scleral and hybrid lenses provide good visual acuity and comfort for keratoconic patients previously intolerant to RGP lenses. RGP lens wear post-cross linking (CXL) is relatively well-tolerated. Contact lenses may still be required post intrastromal corneal ring procedures and post keratoplasty. Scheimpflug imaging and anterior segment optical coherent tomography (ASOCT) are useful in contact lens fitting. Computerized contact lens fitting techniques could reduce the chair time of lens fitting as well as improve comfort and visual performance. Contact lenses play an important role in the visual rehabilitation of keratoconus patients. New contact lens designs and materials have significantly expanded the available fitting options for keratoconus patients. Imaging technology can be utilized to guide contact lens fitting.Subject terms: Rehabilitation, Rehabilitation, Implants     

A retrospective analysis of vision correction and safety in keratoconus patients wearing Toris K soft contact lenses

The purpose of this study was to investigate the efficacy and safety of the Toris K silicone hydrogel contact lens (SwissLens; Prilly, Switzerland) in keratoconus patients. A database with information on 50 keratoconus patients (64 eyes) fitted with Toris K soft contact lenses over a 2-year period was retrospectively reviewed. Demographic data, prefitting refraction, the reason for choosing the Toris K soft contact lens, uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), best-corrected visual acuity with a rigid gas permeable lens (BCVA RGP), best-corrected visual acuity with the Toris K lens (BCVA Toris K), and complications were evaluated. The mean age ± standard deviation at the time of fitting was 27.92 ± 9.86 years. The mean spherical refractive power was ?4.62 ± 6.53 dioptres, and the mean cylinder was ?3.78 ± 2.43 dioptres. The most common reason for using Toris K soft contact lenses was an inability to fit the patient with a RGP contact lens. There was a statistically significant difference between UCVA and BCVA Toris K (p = 0.0001), as well as between BSCVA and BCVA Toris K (p = 0.0001). However, there was no statistically significant difference between BCVA Toris K and BCVA RGP (p = 0.20). Superficial punctate keratitis and giant papillary conjunctivitis were the most common complications. The Toris K contact lens is a viable alternative for the optical management of all grades of keratoconus. The Toris K soft contact lens is a promising alternative for the visual rehabilitation of keratoconus patients who cannot tolerate RGP lenses or achieve a good fit.     

透气硬性角膜接触镜矫治先天性小眼球屈光不正

目的 分析先天性小眼球的屈光参数特点,观察透气硬性角膜接触镜(rigid gas-permeable contactlens,RGP)矫治先天性小眼球的屈光不正的效果,并探讨验配注意事项.方法 对视光门诊确诊先天性小眼球的患者7例14只眼,测量眼轴长度、前房深度和角膜曲率,检影验光和主觉验光,并记录裸眼视力(uncorrected visual acuity,UCVA)和框架眼镜的最佳矫正视力(best spectacle corrected visual acuity,SP-VA),配戴特殊设计的试戴镜,荧光素染色评价配适状态,片上验光追加度数,订制RGP,检查戴RGP的最佳矫正视力(best RGP-corrected visual acuity,RGP-VA)、配适情况,并随访观察.结果 14只先天性小眼球的平均角膜曲率半径(6.93±0.27)mm,前房深度(2.46±0.23)mm,眼轴长度(15.67±0.59)mm,验光度数(+17.29±3.52)D,RGP的平均基弧(6.92±0.19)mm,屈光度(+21.91±4.66)D.全部患者的RGP-VA比UCVA都有显著提高.RGP-VA与SP-VA相当.平均随访时间为20个月(7～29月),镜片配适良好,患者均能坚持全天配戴,未发生与角膜接触镜相关的并发症.结论 先天性小眼球的屈光参数显著不同于正常眼球,角膜异常弯曲、前房浅、眼轴短.屈光呈超高度远视,均伴有弱视.RGP是有效的光学矫正手段.为确保订制的RGP参数准确,需要专用的RGP试戴镜.