Limbal relaxing incisions to correct corneal astigmatism during phacoemulsification

PURPOSE: To evaluate the safety and efficacy of limbal relaxing incisions for the correction of corneal astigmatism during phacoemulsification. METHODS: Fifty eyes of 37 patients (mean age 66.5 years, range: 45 to 80 years) with cataract and coexisting topographic astigmatism were included in the study. Eyes were randomly divided into two groups: eyes that underwent cataract surgery with limbal relaxing incisions (cataract LRI group) and eyes that underwent cataract surgery only (control group). All limbal relaxing incisions were performed during phacoemulsification. Best spectacle-corrected visual acuity (BSCVA), uncorrected visual acuity (UCVA), and corneal topography were recorded preoperatively and 1, 3, and 6 months postoperatively. RESULTS: A statistically significant improvement in BSCVA was seen in the cataract LRI eyes from 0.9 +/- 0.7 preoperatively to 0.1 +/- 0.1 at 1, 3, and 6 months postoperatively (P < .01). A statistically significant improvement in BSCVA was seen in control eyes from 0.8 +/- 0.6 before surgery to 0.2 +/- 0.2 at 1, 3, and 6 months after surgery (P < .01). No difference in postoperative BSCVA was noted between the groups. A statistically significant reduction in the mean topographic astigmatism was seen in the cataract LRI eyes from 1.93 +/- 0.58 diopters (D) preoperatively to 1.02 +/- 0.60 D 6 months postoperatively (P < .05). The control eyes did not show a statistically significant change in topographic astigmatism. CONCLUSIONS: Limbal relaxing incisions performed during phacoemulsification surgery appear to be a safe, effective, and stable procedure to reduce pre-existing corneal astigmatism.     

The Auckland cataract study: co-morbidity, surgical techniques, and clinical outcomes in a public hospital service

AIM: To prospectively assess cataract surgery in a major New Zealand public hospital by defining presenting clinical parameters and surgical and clinical outcomes in a cohort of subjects just below threshold for treatment, based upon a points based prioritisation system. METHODS: The prospective observational study comprised 488 eyes of 480 subjects undergoing consecutive cataract operations at Auckland Hospital. All subjects underwent extensive ophthalmic examination before and after surgery. Details of the surgical procedure, including any intraoperative difficulties or complications, were documented. Postoperative review was performed at 1 day and 4 weeks after surgery. Demographic data, clinical outcomes, and adverse events were correlated by an independent assessor. RESULTS: The mean age at surgery was 74.9 (SD 9.6) years with a female predominance (62%). Significant systemic disease affected 80% of subjects, with 20% of the overall cohort exhibiting diabetes mellitus. 26% of eyes exhibited coexisting ocular disease and in 7.6% this affected best spectacle corrected visual acuity (BSCVA). A mean spherical equivalent of -0.49 (1.03) D and mean BSCVA of 0.9 (0.6) log MAR units (Snellen equivalent approximately 6/48) was noted preoperatively. Local anaesthesia was employed in 99.8% of subjects (94.9% sub-Tenon's). The majority of procedures (97.3%) were small incision phacoemulsification with foldable lens implant. Complications included: 4.9% posterior capsule tears, 3.8% cystoid macular oedema, and one case (0.2%) of endophthalmitis. Mean BSCVA after surgery was 0.1 (0.2) log MAR units (6/7.5 Snellen equivalent), with a mean spherical equivalent of -0.46 (0.89) D, and was 6/12 or better in 88% of all eyes. A drop in BSCVA, thought to be directly attributable to the surgical intervention, was recorded in a small percentage of eyes (1.5%) after surgery. CONCLUSION: This study provides a representative assessment of the management of cataract in the New Zealand public hospital system. A predominantly elderly, female population, frequently exhibiting significant systemic illness and coexisting ocular disease, relatively advanced cataracts, and poor BSCVA, presented for cataract surgery. The majority of subjects underwent small incision, phacoemulsification, day case surgery. While almost 90% achieved at least 6/12 BSCVA post-surgery, approximately 5% sustained an adverse intraoperative event and 1.5% of eyes exhibited a reduction in BSCVA postoperatively.     

The refractive outcome of Toric Lentis Mplus implant in cataract surgery

AIM: To evaluate the refractive outcome of Toric Lentis Mplus intraocular lens (IOL) implant. METHODS: This is a retrospective case series. Consecutive patients with corneal astigmatism of at least 1.5 D had Toric Lentis Mplus IOL implant during cataract surgery. The exclusion criteria included irregular astigmatism on corneal topography, large scotopic pupil diameter (>6 mm), poor visual potential and significant ocular comorbidity. Postoperative manifest refraction, uncorrected distance visual acuity (UDVA), best-corrected distance visual acuity (BCVA), uncorrected intermediate visual acuity (UIVA) at 3/4 m and uncorrected near visual acuity (UNVA) were obtained. RESULTS: There were 70 eyes from 49 patients in this study. Patients were refracted at a median of 8.9wk (range 4.0 to 15.5) from the operation date. Sixty-five percent of eyes had 6/7.5 (0.10 logMAR) or better, and 99% 6/12 (0.30 logMAR) or better postoperative UDVA. Eighty-nine percent could read Jaeger (J) 3 (0.28 logMAR) and 95% J5 (0.37 logMAR) at 40 cm. The median magnitude of astigmatism decreased from 1.91 D to 0.49 D (Wilcoxon, P<0.001) after the operation. The range of the cylindrical error was reduced from 1.5-3.95 D (keratometric) preoperatively to 0.00-1.46 D (subjective refraction transposed to corneal plane) postoperatively. CONCLUSION: Toric Lentis Mplus IOL has good predictability in reducing preexisting corneal astigmatism.     

Evaluation of a toric intraocular lens with a Z-haptic

PURPOSE: To evaluate the efficacy and rotational stability of the MicroSil 6116TU foldable 3-piece silicone toric intraocular lens (IOL) (HumanOptics). SETTING: Department of Ophthalmology, Hillingdon Hospital, Uxbridge, Middlesex, United Kingdom. METHODS: This prospective observational study included 21 eyes of 14 consecutive patients with more than 1.50 diopters (D) of preexisting corneal astigmatism having cataract surgery. Phacoemulsification was performed, and a MicroSil 6116TU toric IOL was inserted through a 3.4 mm temporal corneal incision. LogMAR uncorrected visual acuity (UCVA), best corrected visual acuity, refraction, keratometry, and cylinder axis of the toric IOL were measured. RESULTS: The mean preoperative refractive and keratometric astigmatism was 3.52 D +/- 1.11 (SD) and 3.08 +/- 0.76 D, respectively. Six months postoperatively, the logMAR UCVA in eyes without ocular comorbidity (n = 14) was 0.20 +/- 0.15 (Snellen 20/32). Seventy-nine percent (11 eyes) had a visual acuity of 0.24 (Snellen 20/35) or better. The mean refractive astigmatism at 6 months was 1.23 +/- 0.90 D. Vector analysis using the Holladay-Cravy-Koch method showed a mean reduction in refractive astigmatism of 2.16 +/- 2.33 D. The mean difference between intended and achieved cylinder axis at 6 months was 5.2 degrees (range 0 to 15 degrees). No IOL rotated more than 5 degrees during the follow-up period. CONCLUSIONS: The MicroSil 6116TU toric IOL reduced visually significant keratometric astigmatism and increased spectacle independence. The IOL was stable in the capsular bag, showing no significant rotation up to 6 months postoperatively.     

Corneal suture for the correction of hyperopia following radial keratotomy

PURPOSE: To report the visual and refractive changes observed after double concentric corneal suture to correct hyperopic shift after radial keratotomy (RK). METHODS: This retrospective consecutive case series comprised 17 eyes (15 patients) that underwent two concentric corneal sutures (modified Grene Lasso suture) to correct hyperopic shift after RK. All surgeries were performed by the same surgeon between 2000 and 2003. RESULTS: The mean time after RK was 11.6 +/- 3.2 years. The mean follow-up was 20.3 +/- 11.3 months. The spherical equivalent refraction was reduced from a preoperative mean of +4.38 +/- 2.87 diopters (D) to -0.54 +/- 2.59 D at last postoperative follow-up (P < .001). No statistically significant difference was observed in mean refractive astigmatism before and after the corneal suture (P = .15). Before surgery, no eye presented with best spectacle-corrected visual acuity (BSCVA) > or = 20/20. At final follow-up, 3 (17.6%) eyes attained this level. Seven (41.2%) eyes improved their BSCVA by > or = 2 Snellen lines. One (5.9%) eye lost 2 Snellen lines of BSCVA. CONCLUSIONS: Corneal suture can be used to correct RK-induced hyperopia, improving the corneal asphericity in an attempt to stabilize these corneas. It appeared to be effective even for high degrees of hyperopia and in cases with associated irregular astigmatism or open incisions.     

Improvement of visual acuity following refractive surgery for myopia and myopic anisometropia

PURPOSE: To test the hypothesis that anisometropic adults without significant amblyopia suffer from mild visual impairment probably due to aniseikonia, which might be improved by corneal refractive surgery. METHODS: Fifty-seven patients presenting with myopic anisometropia > or = 3.25 diopters (D) and 174 myopic controls appropriate for refractive surgery were included. Photorefractive keratectomy (PRK) or LASIK was performed on 57 anisometropic eyes. As 43 of the 174 myopic control patients had bilateral surgery, PRK or LASIK was performed on 217 myopic control eyes. Best spectacle-corrected visual acuity (BSCVA), refraction, and refractive correction were measured preoperatively and at 1, 3, 5 to 7, 8 to 13, and 25 months following surgery. RESULTS: Preoperative mean spherical equivalent was -7.20 +/- 2.40 D for anisometropic patients and -6.40 +/- 1.90 D for myopic patients. At 8 to 13 months postoperatively, when 23 (40%) anisometropic eyes and 94 (43%) myopic eyes were examined, the mean spherical equivalent refractions were -0.80 +/- 1.60 D and -0.30 +/- 0.60 D, respectively. Preoperatively, the mean BSCVA on a logMAR scale was -0.0143 +/- 0.0572 (Snellen 0.98 +/- 0.12) in the anisometropic group and 0.0136 +/- 0.0361 (Snellen 1.04 +/- 0.09) in the control group (P = .001). Eight to 13 months postoperatively, these values were 0.0076 +/- 0.0659 (Snellen 1.03 +/- 0.15) and 0.0495 +/- 0.0692 (Snellen 1.13 +/- 0.18) and this difference remained statistically significant (P = .012). For the myopic patients, the improvement in BSCVA reached almost maximum at 3 months, and this improvement was found to be highly significant 3 months after surgery (P = .001). The improvement in BSCVA was significantly slower for anisometropic patients and became statistically significant only after 8 to 13 months postoperatively (P = .041). CONCLUSIONS: Anisometropia reduces visual acuity in the more myopic eye and can be at least partially reversed by refractive correction. The slower improvement in BSCVA for anisometropic patients suggests plastic changes in the visual cortex following refractive surgery.     

Toric人工晶状体矫正角膜散光的效果评价

目的评价Toric人工晶状体（IOL）矫正角膜散光的效果及在囊袋内的稳定性。方法收集确诊为年龄相关性白内障并伴有角膜规则散光的患者32例（35眼）,采用白内障超声乳化法植入ToricIOL。观察术前、术后裸眼视力（UCVA）及最佳矫正视力（BCVA）、术前角膜散光、预计残余散光、术后残余散光、IOL旋转度,并进行分析。结果术后3个月92%患眼UCVA≥0.5,78%患眼UCVA≥0.8,BCVA≥0.8者达96%。术前角膜散光平均为（1.500±0.405）D,术后3个月残余散光为（0.200±0.179）D。3个月时与术后第1d轴位相比较,IOL旋转平均为（2.132±1.853）°。结论ToricIOL可使患者获得更好的裸眼远视力,减少了患者的残余散光,预测性强,具有良好的旋转稳定性,是一种有效的矫正角膜规则散光的治疗方法。     

2.2 mm透明角膜切口飞秒激光辅助白内障超声乳化手术术源性散光的临床研究

目的观察飞秒激光辅助白内障超声乳化手术中2.2 mm透明角膜切口引起的术源性散光（SIA）的影响因素。方法前瞻性研究。纳入2014年3月至2016年4月期间,在山西省眼科医院白内障一科行飞秒激光辅助白内障超声乳化手术的患者84例（105眼）,测量并记录患者术前,术后1、3、6个月的裸眼视力（UCVA）,球镜度和角膜地形图数据。视力记录为logMAR视力,使用Alpins矢量分析法计算SIA。并从术后随访时间（术后1、3、6个月3个时间点）、晶状体核硬度（分Ⅱ、Ⅲ、Ⅳ级核3组）、角膜散光类型（分顺规组、逆规组、斜轴组）、眼别（左眼组、右眼组）4个方面分析SIA。符合正态性分布的数据的比较使用重复测量的方差分析。结果84例（105眼）患者UCVA术前为0.65±0.24,术后1、3、6个月为0.07±0.02、0.06±0.01、0.06±0.01;手术前后比较差异有统计学意义（F=321.14,P<0.01）;术后各时间点比较差异无统计学意义。术后1、3、6个月SIA分别为（0.28±0.11）D、（0.25±0.13）D、（0.24±0.10）D;3个时间点比较差异无统计学意义。按晶状体核硬度分组从时间上及组别间比较差异均无统计学意义;顺规组、逆规组、斜轴组3组从时间上及组别间比较差异均无统计学意义;右眼组与左眼组从时间上及组别间比较差异均无统计学意义。结论2.2 mm透明角膜切口飞秒激光辅助白内障超声乳化术后SIA稳定,术后UCVA显著提高,且SIA与UCVA于术后1个月趋于稳定。     

飞秒激光撕囊复曲面人工晶状体植入的临床观察

目的　观察飞秒激光辅助超声乳化白内障吸出术联合Toric 人工晶状体（toric intraocular lens,Toric IOL）植入矫正散光的效果以及IOL的旋转稳定性与居中性。方法　本文为前瞻性非随机对照研究。收集确诊为年龄相关性白内障并伴有角膜规则散光>1.0 D的患者68例（82眼）,其中41眼采用飞秒激光辅助超声乳化白内障吸出术联合Toric IOL植入术（观察组）,另41眼采用传统超声乳化术联合Toric IOL植入术（对照组）。观察并比较术前和术后6个月患者的裸眼视力、残余散光的度数;采取重复测量分析比较两组术后1个月、3个月、6个月IOL轴位旋转的度数及IOL在囊袋内水平、垂直偏移的距离和垂直偏转的度数。结果　观察组术前裸眼视力（logMAR）为1.03±0.32,术前角膜散光为（2.09±0.73）D,术后最佳矫正视力为0.13±0.11,术后6个月残余散光度数为（0.33±0.27）D;对照组术前裸眼视力为0.92±0.40,术前角膜散光为（1.69±0.64）D,术后最佳矫正视力为0.13±0.09,术后6个月残余散光度数为（0.26±0.22）D;与术前相比,两组患者术后视力均明显提高,散光明显降低,差异均有统计学意义（均为P<0.001）;两组比较,术后1个月、3个月、6个月IOL轴位旋转的度数差异均无统计学意义（均为P>0.05）,但IOL水平偏移距离与垂直偏移距离差异均有统计学意义（均为P<0.05）;两组术后1个月、3个月、6个月的IOL倾斜度差异均有统计学意义（均为P<0.05）。结论　飞秒激光辅助Toric IOL植入术与超声乳化白内障吸出术联合Toric IOL植入术后均有良好的旋转稳定性和可预测性。     

Refractive change in response to acute hyperbaric stress in refractive surgery patients

PURPOSE: To determine whether acute hyperbaric stress affects visual acuity or refractive power after keratorefractive surgery. SETTING: Clinical multiplace hyperbaric chamber and ophthalmology clinic, University of California, San Diego, California, USA. METHODS: This prospective convenience sample study included 3 groups: 3 patients who had had bilateral myopic radial keratotomy (RK); 2 who had had bilateral myopic laser in situ keratomileusis (LASIK); and 4 control subjects who had no previous corneal refractive surgery or ocular pathology but had a myopic refractive error (-1.25 to -8.38 diopters [D]) similar to that in the treated patients before refractive surgery. One additional patient had had unilateral LASIK only and was included in the LASIK and control groups. Best spectacle-corrected visual acuity (BSCVA), manifest spherocylindrical refractive error, and intraocular pressure were measured at baseline, at 4 atmospheres absolute (atm abs), and on return to ambient pressure. Corneal pachymetry and keratometry were measured at baseline and on return to ambient pressure. RESULTS: The mean BSCVA changed from 0.06 logMAR (20/25 Snellen equivalent) at baseline to 0.10 logMAR (20/25) at 4 atm abs in the RK group and from 0.00 logMAR (20/20) to -0.06 logMAR (20/15) in the LASIK group; it did not change in the control group. The mean refractive error changed from 0.25 D at baseline to 0.50 D at 4 atm abs in the RK group, from -0.90 to -1.02 D in the LASIK group, and from -4.58 to -4.53 D in the control group. CONCLUSIONS: Acute hyperbaric stress did not appear to alter refractive power after corneal surgery.     

Wavefront-supported photorefractive keratectomy with the Bausch & Lomb Zyoptix in patients with myopic astigmatism and suspected keratoconus

PURPOSE: To evaluate the safety, efficacy, and visual outcome of wavefront-supported photorefractive keratectomy (PRK) for the correction of myopia and myopic astigmatism in patients with suspected keratoconus. METHODS: Forty eyes of 20 patients with myopia -4.0 to -8.0 diopters (D) (mean: -6.25 +/- 1.04 D), cylinder -1.0 to -2.50 D (mean: -1.61 +/- 0.71 D), and corneal thickness 440 to 488 microm were treated with wavefront-supported PRK. Corneal topography evaluation revealed a significantly irregular cylinder (inferior-superior difference > 1.5 D) with possible mild or forme fruste keratoconus. Aberrometry was performed with the Hartmann-Shack aberrometer, and corneal data were evaluated with the Orbscan system. Eyes were treated with the Technolas 217z Bausch & Lomb excimer laser and followed for a minimum of 40 months. RESULTS: Following surgery, mean spherical equivalent refraction was +0.33 +/- 0.8 D. It was within +/- 0.5 D of the intended refraction in 95% of eyes and within +/- 1.0 D in 100% of eyes. Mean uncorrected visual acuity improved from 20/400 preoperatively to 20/25 postoperatively. Mean best spectacle-corrected visual acuity (BSCVA) remained unchanged (20/20) or improved to 20/20 in 92.5% of eyes and to 20/25 in 7.5% of eyes. Individually, BSCVA did not change in 28 (70%) eyes and increased by > or = 2 Snellen lines in 9 (22.5%) eyes; 3 (7.5%) eyes lost 1 Snellen line because of corneal haze. Laser treatment induced a significant flattening of the preoperative inferior corneal steepness in all eyes. Wavefront analysis demonstrated a significant decrease in high order aberrations (total root-mean-square and coma). CONCLUSIONS: Wavefront-supported PRK appears to be effective for the treatment of myopia and astigmatism in patients with suspected keratoconus and thin, irregular corneas. Longer follow-up is needed to prove the safety of the procedure in this patient population.     

Topography-guided custom ablation for irregular corneal astigmatism using the NIDEK NAVEX Laser System

PURPOSE: To determine whether topography-guided custom ablation produces acceptable outcomes in the treatment of irregular corneal astigmatism caused by previous corneal surgery or corneal disease. METHODS: Thirteen eyes of nine patients who had irregular corneal astigmatism from previous corneal surgery or corneal disease were treated with customized aspheric treatment zone (CATz) ablations using the NIDEK Advanced Vision Excimer Laser System (NAVEX). Changes in corneal surface regularity index, surface asymmetry index, asymmetry component, corneal and ocular higher order aberrations, uncorrected visual acuity, and best spectacle-corrected visual acuity (BSCVA) were analyzed using Wilcoxon and paired t tests. A P value < .05 was considered statistically significant. RESULTS: After CATz treatment, 62% of eyes (8 of 13) showed an increase in BSCVA. Improvements in both the surface asymmetry index and asymmetry components were statistically significant after CATz treatment (P < .05). CONCLUSIONS: Topography-guided custom ablation can be safe and effective in the management of irregular corneal astigmatism due to previous corneal surgery or corneal disease.     

白内障术后晶状体后囊膜混浊及远期视力下降影响因素分析

目的探讨白内障术后晶状体后囊膜混浊(posterior capsular opacification,PCO)发生及术后远期视力下降的影响因素。方法收集行白内障超声乳化摘出联合人工晶状体植入术的年龄相关性白内障患者37例(47眼),记录患者术前、术后的眼部检查情况及是否行后囊膜抛光处理等术中情况,于术后2a对PCO进行分级评价。结果 47眼中,有25眼在术后2a发生了PCO,其中18眼混浊已累及中心3mm区,4眼已行YAG激光后囊膜切开术,后囊膜切开率8.5%。统计分析显示,PCO和混浊累及中心3mm区的发生率在是否行后囊膜抛光眼之间的差异均有统计学意义(均为P<0.05)。在各因素中,行后囊膜抛光是发生PCO以及混浊累及中心3mm区仅有的保护性因素。累及中心3mm区的PCO、眼底疾病和黄斑病变与术后2a视力变化之间的关联均有统计学意义(均为P<0.05)。结论白内障术后发生累及中心3mm区的PCO可导致术后远期视力下降;术中行后囊膜抛光处理可显著降低PCO的发生率和严重程度。     

Rate of posterior capsule opacification in eyes with the Akreos intraocular lens

PURPOSE: To determine the rate of posterior capsule opacification (PCO) in eyes with an Akreos Adapt or Akreos Fit intraocular lens (IOL) (Bausch & Lomb) over a minimum follow-up of 18 months. SETTING: Department of Ophthalmology, Worthing and Southlands Hospital NHS Trust, Worthing, United Kingdom. METHOD: This was a retrospective analysis of 102 patients who had uneventful phacoemulsification with implantation of an Akreos Adapt IOL or Akreos Fit IOL from September 2001 to May 2004. Patients from a single surgeon's operating list were recruited into the study. Exclusion criteria included posterior subcapsular cataract, history of uveitis, diabetic retinopathy, glaucoma, and age-related macular degeneration. The protocol included the determination of logMAR best corrected visual acuity (BCVA) and PCO scoring using the Evaluation of Posterior Capsular Opacification System (EPCO 2000) by digital photography of the posterior capsule. The number of patients having a neodymium:YAG (Nd:YAG) capsulotomy was also recorded. RESULTS: The mean follow-up was 30 months +/- 10.3 (SD). The mean BCVA was 20/32 (0.2 logMAR). The mean EPCO score at the central 6.0 mm of the posterior capsule was 0.39 +/- 0.53 and at the central 3.0 mm, 0.18 +/- 0.40. The Nd:YAG capsulotomy rate was 8.8%. CONCLUSIONS: All patients had stable visual acuity with low rates of PCO 2.5 years after surgery. The PCO rate with the Akreos IOL was similar to that with other acrylic IOLs reported in the literature.     

Phototherapeutic keratectomy for epithelial irregular astigmatism: an emphasis on map-dot-fingerprint degeneration

PURPOSE: To study the changes in irregular astigmatism in patients with recurrent corneal erosion syndrome due to map-dot-fingerprint degeneration and to demonstrate that both symptomatic and asymptomatic map-dot-fingerprint degeneration/recurrent corneal erosion syndrome may be related to irregular astigmatism, which can effectively be corrected by phototherapeutic keratectomy (PTK) or standard spherical photorefractive keratectomy (PRK). METHODS: Eleven eyes with irregular astigmatism related to map-dot-fingerprint degeneration/recurrent corneal erosion syndrome with and without changes at the slit-lamp microscope were treated with PTK or spherical PRK, which was performed with a VISX S2 or S4 excimer laser. All eyes underwent videokeratography performed pre- and postoperatively using either the Tomey TMS-2N Topographic Modeling System or EyeSys Technologies Corneal Analysis System 2000. RESULTS: Mean pre- and postoperative best spectacle-corrected visual acuity (BSCVA) was -0.18 +/- 0.14 logMAR and 0.04 +/- 0.04 logMAR, respectively. This improvement in BSCVA was statistically significant. The mean gain in Snellen lines was 2.4 +/- 2.1. Preoperative corneal videokeratography showed irregular astigmatism with an elevation pattern that was corrected in all eyes despite the fact that no astigmatic photorefractive correction was performed. CONCLUSIONS: Following PTK, eyes with irregular astigmatism related to map-dot-fingerprint degeneration showed significant improvement in BSCVA and correction of irregular astigmatism as revealed by videokeratography. This study shows that irregular astigmatism can be exclusively of epithelial origin and in some eyes abnormal corneal epithelium may create optical aberrations. This possibility should be taken into account when, for example, wavefront-guided stromal photoablation procedures are being planned.     

Topographically guided excimer laser photorefractive keratectomy to treat superficial corneal opacities

OBJECTIVE: To demonstrate the efficacy and safety of topographically guided excimer laser photorefractive keratectomy (PRK) in treating superficial corneal opacities. DESIGN: Prospective, noncomparative interventional case series. METHODS: Twenty-six eyes of 24 patients with postinfectious (n = 6), post-traumatic (n = 18), and post-PRK (n = 2) scars were treated with an excimer laser linked to a computerized videokeratography unit with a topographically supported customized ablation workstation. MAIN OUTCOME MEASURES: Manifest spectacle refraction, best spectacle-corrected visual acuity (BSCVA), uncorrected visual acuity (UCVA), change of corneal clarity, and topographic indexes of surface regularity. RESULTS: The mean follow-up period was 7.7+/-2.1 months (+/- standard deviation) (range = 6-12). Corneal clarity and corneal topography patterns improved in all eyes. Uncorrected visual acuity improved from 0.7+/-0.8 logarithm of the minimum angle of resolution (logMAR) to 0.4+/-0.5 logMAR (P = 0.008), and BSCVA improved from 0.3+/-0.6 logMAR to 0.1+/-0.6 logMAR (P<0.001). The BSCVA increased in all eyes (>/=2 lines in 76.9% of eyes and 1 line in 23.1%). The mean spherical equivalent refraction changed from -0.125+/-2.77 diopters (D) to +1.33+/-1.28 D (P = 0.019). CONCLUSIONS: The use of topographically guided PRK with the topographically supported customized ablation method resulted in significant increases of UCVA and BSCVA and improved corneal clarity in all patients. The technique seems to be safe and effective for treating various superficial corneal diseases, including postinfectious, post-traumatic, and post-PRK scars.     

超声乳化术与小切口非超声乳化术治疗白内障疗效比较

目的：比较超声乳化术与小切口非超声乳化术治疗老年性白内障的临床疗效。

方法：白内障患者355例393眼分成A、B两组,其中A组180例193眼施行小切口非超声乳化白内障手术,B组175例200眼施行超声乳化白内障手术。术后观察视力、角膜散光、角膜内皮细胞计数情况。

结果：术后1d,患者视力恢复情况超声乳化手术组明显优于小切口非超声乳化手术组,但术后7d和30d两组无显著差异。术后7d,小切口非超声乳化组角膜散光度明显高于超声乳化组,但术后30d无显著性差异。对核硬度在Ⅳ～Ⅴ级的患者,超声乳化术后角膜内皮细胞计数少于小切口非超声乳化组,统计学分析有显著差异。

结论：应针对老年性白内障患者核硬度的具体情况,选择合适的手术方式进行治疗。     

Higher-order aberrations of lenticular opacities

PURPOSE: To measure and quantify higher-order aberrations induced by different types of lenticular opacities. SETTING: Department of Ophthalmology, University of Auckland, and Department of Ophthalmology, Auckland Public Hospital, Auckland, New Zealand. METHODS: Patients with lenticular opacities were recruited from outpatient clinics of a major tertiary referral center for ophthalmology. Patients were included if they had clinically evident, mild to moderate lenticular opacity with no coexisting ocular pathology. Patients were examined using standard preoperative techniques with additional assessment by wavefront aberrometry (Zywave, Bausch & Lomb) and Scheimpflug photography (EAS-1000, Nidek). For comparison, 20 eyes of 10 subjects with no lenticular opacity (control group) were recruited and assessed in an identical manner. RESULTS: Thirty persons were recruited and 40 eyes assessed, 20 with lenticular opacities. Ten eyes had predominantly cortical opacification, and 10 had mainly nuclear opacification. In eyes with predominantly cortical opacification, the mean logMAR uncorrected visual acuity (UCVA) was 0.5 +/- 0.2 (SD) (6/18 Snellen equivalent) and the mean logMAR best spectacle-corrected visual acuity (BSCVA), 0.2 +/- 0.2 (6/9). Analysis of aberrometry data for a 6.0 mm pupil in this group revealed an increase in coma of cosine phase (Z(3), P =.06) and tetrafoil of cosine phase (Z(4), P =.07) compared to eyes in the control group. Eyes with predominantly nuclear opacification had a mean logMAR UCVA of 0.7 +/- 0.2 (6/30) and a logMAR BSCVA of 0.4 +/- 0.2 (6/15). Aberrometry data for this cohort for a 6.0 mm pupil showed a statistically greater amount of spherical aberration (Z(4)(0), P =.001) and tetrafoil of cosine phase (Z(4), P =.005; Z(4)(-4), P =.004). CONCLUSIONS: This pilot study suggests that different types of early lenticular opacities induce different wavefront aberration profiles. Predominantly cortical opacification produced an increase in coma and nuclear opacification induced an increase in spherical aberration compared to eyes without opacities. Both types of lenticular opacities also induced a higher amount of tetrafoil. This could explain the significant visual symptoms in patients with early cataract and relatively good high-contrast Snellen acuity.     

Early clinical outcome with a new monofocal microincision intraocular lens

The purpose of this study was to evaluate the early visual and refractive outcomes of a new aspheric monofocal microincision intraocular lens (IOL). This retrospective case series included eyes of patients who underwent implantation of a microincision IOL following 1.8 mm manual coaxial microincision cataract surgery and who attended regular postoperative follow-up visits on the first week and first, third, and sixth months. The postoperative uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), refraction and predictability, intraoperative and postoperative complications, posterior capsule opacification (PCO), IOL centration, and surgically induced astigmatism (SIA) were evaluated. Sixty-three eyes of 38 patients ranging in age from 51 to 86 were included in the study. The mean preoperative BCVA was 0.52 ± 0.42 logMAR. At the postoperative sixth month, the mean postoperative UCVA and BCVA were 0.12 ± 0.11 and 0.01 ± 0.03 logMAR, respectively. The mean postoperative spherical equivalent refraction (SER) was ?0.30 ± 0.49 D. The SER was within ± 1.00 D of the attempted correction in 95.2 % of the eyes. The mean SIA measured with vector analysis was 0.45 ± 0.28 D. Mild PCO was observed in 9 eyes (14.7 %) with none requiring Nd:Yag laser capsulotomy. On centration analysis, the IOL was found to be 0.26 mm on average to the supero-nasal position. The aspheric microincision IOL was safely implanted and provided satisfactory visual and refractive outcomes in the early postoperative period.     

Long-term outcomes of photorefractive keratectomy in eyes with previous epikeratophakia for keratoconus

PURPOSE: To determine the long-term safety and effectiveness of photorefractive keratectomy (PRK) in the treatment of refractive errors after epikeratophakia (EP) for keratoconus. METHODS: Ten patients (14 eyes) who had refractive errors after EP for keratoconus received PRK surgery. Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), refractive error, corneal astigmatism, pachymetry, corneal topography, and complications were monitored. RESULTS: Mean follow-up after PRK was 63.4 +/- 19.8 months. Mean spherical equivalent was -5.5 +/- 3.9 D before PRK, -0.9 +/- 0.5 D at 1 month after PRK, and -1.5 +/- 1.0 D at 3 years. Mean astigmatism was 4.2 +/- 2.1 D before PRK, 1.2 +/- 0.5 D at 1 month after PRK, and 1.5 +/- 0.6 D at 3 years. Thirteen (93%) eyes had an UCVA <20/40, and 12 (86%) had a BSCVA of 20/40 or better before PRK. At 1 year, the UCVA was 20/40 or better in 8 (57%) eyes, and the BSCVA was 20/40 or better in all eyes. Mean central corneal thickness was 749 +/- 35 microm before PRK and 621 +/- 56 mum at 3 years. During the follow-up period, haze (grade no more than 1.0) was observed in 2 eyes. No immune rejection episode or recurrent keratoconus was found. CONCLUSIONS: PRK appears to be reliable and safe for the correction of residual ametropia after EP for keratoconus, and the visual acuity can remain stable after PRK for a long time.