Conductive keratoplasty for presbyopia: 3-year results

PURPOSE: To assess the long-term safety, efficacy, and stability of conductive keratoplasty (CK) in the treatment of presbyopia. METHODS: Ten near-plano presbyopic patients (6 women and 4 men) underwent unilateral CK with standard-pressure technique in the non-dominant eye to improve their near vision. Mean age was 51+/-3.1 years (range: 46 to 56 years). Nine of the 10 patients were available for both 1- and 3-year follow-up examinations. RESULTS: Preoperative mean manifest refraction spherical equivalent (MRSE) was -0.17+/-0.29 diopters (D), yielding a mean near uncorrected visual acuity (UCVA) of J10. Three years after CK, the mean near UCVA was J3. The mean MRSE at 3 years was -1.06+/-0.81 D, which represents a 0.25 D change from the MRSE at 1 year. The MRSE in the dominant untreated eyes had a +0.26 D change during the 3-year period, which was not statistically different when compared to the CK-treated eyes during the 3-year postoperative period. No eye lost best spectacle-corrected visual acuity or had induced cylinder > or =0.75 D. Seventy-eight percent had binocular distance UCVA 20/20 or better and near UCVA J3 or better. The average keratometry remained stable at 45.09 D 3 years postoperatively compared to 45.08 D 1 year postoperatively. CONCLUSIONS: Conductive keratoplasty for the treatment of presbyopia provided safe, effective, predictable, and stable results 3 years following the initial surgery. Refractive stability was similar for both the CK-treated and untreated eyes with a small hyperopic shift noted during the 3-year follow-up period.     

CK和LASIK治疗老视的临床效果对比研究

目的:比较分析传导性角膜成形术(conductive keratoplas-ty,CK)和准分子激光原位角膜磨镶术(laser in situ kera-tomileusis,LASIK)应用单眼视治疗老视的临床效果和视觉质量。方法:21例(26眼)及24例(41眼)老视患者分别接受CK和LASIK治疗,术前患者屈光度球镜+0.75~+2.0D,散光≤+0.75D,术后预期目标屈光度主导眼矫正为0~-0.5D,非主导眼矫正为-1.5~-2.5D近视状态且近视力≥0.5(J3),术后随访1a。结果:术后1aCK组和LASIK组双眼裸眼视力≥0.8且近视力≥J3者分别为52.4%、66.7%,近视力≥0.33(J4)者分别为81.0%、87.5%,两组与术前相比均有显著性差异(P<0.01),两组间相比较无显著性差异(P>0.05);术眼等效球镜屈光度与预期目标相差±0.5D以内者分别为42.3%、70.7%,两组相比较差异有显著性(P<0.05);术眼散光度在±0.75D以内者分别为57.7%、92.7%,两组相比较差异有显著性(P<0.05);术眼角膜光学视功能区CK组和LASIK组相比较无显著性差异;两组患者术眼对比敏感度较术前均无明显下降;术后1a患者术眼有干眼症状者CK组为3眼(11.5%),LASIK组为8眼(19.5%),两组相比较无显著性差异(P>0.05)。结论:应用单眼视原理采用CK和LASIK治疗老视均取得了较满意的疗效,两种手术方式的远期疗效和稳定性有待进一步观察。     

传导性角膜成形术治疗老视眼的临床效果观察

目的:探讨应用单眼视原理采用传导性角膜成形术(Conductive keratoplasty,CK)治疗老视的临床效果、安全性及可预测性。方法:选择31例(40眼)有明显老视症状的患者,术前屈光度球镜+0.50~+2.50D,散光≤+0.75D,采用CK进行治疗,术后预期目标屈光度主导眼矫正为0.00~-0.50D,非主导眼术后目标屈光度为-1.50~-2.50D,且近视力≥0.5(J3),术后随访1a以上。结果:术后1a双眼裸眼远视力≥0.8且近视力≥0.5(J3)或近视力≥0.33(J4)者分别为61.3%,74.2%;与术前相比均有显著性差异(P<0.01);术后1a等效球镜屈光度与预期目标差值在±0.50D、±1.00D以内者分别为45.0%,82.5%;术后1a术眼散光度在±1.00D以内者为87.5%;术后双眼各空间频率对比敏感度与术前相比较差异无统计学意义(P>0.05);术后1a无最佳矫正视力下降,无严重干眼症的发生;术后1a90.3%的患者表示满意。结论:应用单眼视原理采用CK治疗老视取得了较好的临床疗效,但其远期疗效和稳定性有待进一步观察。     

Treatment of presbyopia with conductive keratoplasty: six-month results of the 1-year United States FDA clinical trial

PURPOSE: To provide 6-month results of a 1-year clinical trial evaluating conductive keratoplasty (CK) for the treatment of presbyopic symptoms in emmetropic and hyperopic eyes. METHODS: A total of 143 patients with presbyopic symptoms were enrolled in this 1-year United States FDA clinical trial and treated to improve near vision in 1 eye (unilateral treatment). In addition, 33 fellow eyes were treated to improve distance vision (bilateral treatment). For near vision correction, the target refraction was up to -2.0 D in the nondominant eye, and for distance vision correction, 0.0 D. Enrolled patients had a preoperative spherical equivalent of plano to +2.00 D, no more than 0.75 D of refractive astigmatism, and were 40 years of age or older. No retreatments were performed. RESULTS: Of the eyes treated for near, 77% had uncorrected near vision of J3 or better at 6 months postoperatively. A total of 85% of all patients had binocular distance UCVA of 20/25 or better along with J3 or better near, a combination that represents functional acuity for a presbyope. Sixty-six percent of eyes treated for near had a manifest refractive spherical equivalent (MRSE) within +/- 0.50 D of intended at 6 months. In 89% of eyes, the MRSE changed 0.05 D or less between 3 and 6 months postoperatively. After month 1, the incidence of variables associated with safety was 1% or lower. Seventy-six percent were very satisfied or satisfied with their procedure. CONCLUSIONS: CK appears to be very safe and effective in producing functional visual acuity in presbyopic eyes up to 6 months following the procedure. Patient satisfaction with the procedure is similar to that of monovision LASIK.     

Photopic pupillometry-guided laser in situ keratomileusis for hyperopic presbyopia

PURPOSE: To evaluate a method of surgically treating presbyopia in hyperopic patients having laser in situ keratomileusis (LASIK) by selecting excimer ablation optical zone diameters based on the photopic pupil. SETTING: Private practice, Beverly Hills, California, USA. METHODS: This prospective analysis comprised 46 patients having hyperopic LASIK for presbyopia. The distance-dominant eye was treated with a standard 6.0 mm optical and 9.0 mm outer zone for full distance correction with no nomogram adjustment from the final preoperative manifest refraction. In the nondominant eye, an algorithm was used to select the optical and blend zone diameters and the optical zone size-dependent programmed amount of correction augmentation. Variables evaluated at the 6-month postoperative visit included preoperative and postoperative manifest refractive spherical equivalent (MRSE), refractive cylinder, and monocular and binocular near and distance uncorrected visual acuities. Patient satisfaction and spectacle dependence were also evaluated. RESULTS: In the near-corrected eye, the mean preoperative and postoperative MRSE was +1.10 diopters (D) +/- 1.20 (SD) and -1.30 +/- 0.56 D, respectively, and the mean refractive cylinder, -0.76 +/- 0.91 D and -0.36 +/- 0.33 D, respectively (P<.05). The mean uncorrected near acuity in the near-corrected eye was J10 preoperatively and J1 postoperatively (P<.0001) and the binocular mean uncorrected near acuity, J10 and J1, respectively (P<.0001). The mean uncorrected logMAR distance acuity in the near-corrected eye was +0.38 +/- 0.31 (20/50) preoperatively and +0.36 +/- 0.25 (20/50) postoperatively (P>.05). The mean binocular uncorrected logMAR distance acuity was +0.30 +/- 0.30 (20/40) and +0.01 +/- 0.08 (20/20) (P<.0001), respectively. The mean overall patient satisfaction score was 8.8 (scale 1 to 10). After LASIK, no patient reported using spectacles full time for near or distance and 15% reported part-time use. CONCLUSION: Photopic pupillometry-guided LASIK may be an effective option when considering surgical treatment of presbyopia in hyperopic patients.     

Correction of presbyopia in hyperopia with a center-distance, paracentral-near technique using the Technolas 217z platform

PURPOSE: To analyze the results of hyperopic patients treated with a peripheral presbyLASIK algorithm for the correction of presbyopia. METHODS: The study included 44 eyes of 22 hyperopic patients treated with a peripheral presbyLASIK technique using a Technolas 217z excimer laser. Mean patient age was 56 years (range: 47 to 72 years), mean preoperative spherical equivalent refraction was +1.21 +/- 0.77 diopters (D) (range: +0.50 to +4.00 D), and mean spectacle near addition was +1.76 +/- 0.42 D (range: +1.00 to +2.75 D). The Peripheral Multifocal LASIK (PML) ablation pattern creates a multifocal corneal profile over a 6.5-mm diameter, performing the distance correction first in a 6-mm optical zone and then near correction in a 6.5-mm zone. Main outcome measures were uncorrected visual acuity (UCVA) and best spectacle-corrected visual acuity (BSCVA) for near and distance, spherical equivalent refraction, contrast sensitivity, and corneal aberrations. RESULTS: Six months postoperatively, mean binocular UCVA was 1.06 +/- 0.13 for distance and 0.84 +/- 0.14 for near. Mean postoperative spherical equivalent refraction was -0.42 D (range: -1.12 to +0.87 D). Two (4.5%) eyes lost 1 line of BSCVA for distance and near vision, and 20 (45%) eyes gained 1 line of distance BSCVA. Contrast sensitivity decreased for 3, 6, 12, and 18 cycles/degree. Corneal aberration analysis showed a slight increase in coma and decrease in spherical aberration. CONCLUSIONS: The peripheral presbyLASIK technique used in this study is a safe and efficient treatment that may improve functional near vision in presbyopic patients with low and moderate hyperopia (from +0.50 to +3.00 D).     

Videokeratography in conductive keratoplasty

PURPOSE: We used EyeSys videokeratography to evaluate corneal shape changes induced by conductive keratoplasty, a procedure that utilizes radio frequency energy to alter corneal shape to correct hyperopia. METHODS: Follow-up data were available for 19 eyes (out of 24 eyes of 13 patients). Preoperative spherical hyperopia ranged from +0.75 to +3.25 D with astigmatism <0.75 D. Manifest refractive spherical equivalent refraction (MRSE), uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), topographical parameter predicted corneal acuity (PCA), corneal uniformity index (CU Index), regular astigmatism, total astigmatism, average simulated keratometry (Avg Sim K), effective refractive power, and asphericity were measured preoperatively and at 6 and 12 months postoperatively. RESULTS: Twelve months postoperatively, mean PCA, CU Index, and BSCVA were maintained at preoperative levels. Mean UCVA (LogMAR) improved from 0.53+/-0.21 to 0.10+/-0.19 (P<.05) with a mean MRSE change from +1.62+/-0.76 D to -0.06+/-0.84 D (P<.05) from preoperative to 12 months postoperative. Mean asphericity increased +0.044+/-0.24 D (P>.05), mean Avg Sim K increased 1.88+/-0.72 D (P<.05), mean effective refractive power increased 1.71+/-0.79 D (P<.05), mean cylinder (cycloplegic refraction) increased 0.19+/-0.36 D (P<.05), mean regular astigmatism increased 0.25+/-0.49 D (P>.05), and mean irregular astigmatism decreased 0.01+/-0.13 D (P>.05) from preoperative to 12 months after conductive keratoplasty. CONCLUSIONS: Avg Sim K and effective refractive power changes support the refractive results; 12-month postoperative maintenance of BSCVA, PCA, and CU Index suggest the procedure is safe. Conductive keratoplasty induced a slight regular astigmatism in some eyes, which decreased with time. The increase in mean corneal asphericity indicated possible induction of central and peripheral cornea changes.     

Correction of presbyopia by technovision central multifocal LASIK (presbyLASIK)

PURPOSE: To investigate central multifocal presbyLASIK based on the creation of a central hyperpositive area. METHODS: Twenty-five patients (50 eyes) underwent presbyLASlK in an open-label, prospective, non-comparative pilot study. Mean patient age was 58 years (range: 51 to 68 years), mean preoperative spherical equivalent refraction was +1.6 +/- 0.63 diopters (D) (range: +0.50 to +3.00 D), and mean spectacle near addition was +2.27 +/- 0.37 D (range: +1.75 to +3.00 D). The ablation pattern was performed with proprietary software from Technovision using an H. Eye Tech. excimer laser platform. RESULTS: Mean postoperative spherical equivalent refraction was -0.37 +/- 0.55 D (range: -1.50 to + 1.00 D) and mean spectacle near addition was +1.72 +/- 0.34 D (range: +1.25 to +2.25 D). After 6 months, 16 (64%) patients achieved a distance uncorrected visual acuity (UCVA) of > or = 20/20 and 18 (72%) patients achieved a near UCVA of > or = 20/40. Seven (28%) patients lost a maximum of 2 lines of best spectacle-corrected visual acuity (BSCVA). The safety index for distance was 0.98 binocular and for near was 0.99 binocular. After 6 months, no significant change was noted in contrast sensitivity at 1.5 cycles/degree. A significant mean reduction was found at spatial frequencies of 3, 6, 12, and 18 cycles/degree (P<.001). There was a significant change in corneal aberrations after surgery. The coefficients for coma increased and the coefficients for spherical aberrations decreased. A significant decrease was noted in point spread function values (P=.0018). CONCLUSIONS: Central presbyLASIK may be used to provide improvement in functional near vision in patients with presbyopia associated with low and moderate hyperopia. However, factors involved in the loss of BSCVA in some cases and loss in vision quality should be further clarified prior to its general use.     

单眼视LASIK治疗伴有老视的屈光不正临床观察

目的:探讨单眼视准分子激光原位角膜磨镶术(单眼视LASIK)治疗伴有老视的屈光不正对患者视觉质量、生活质量的影响。方法:屈光不正伴老视的患者172例中124例施行单眼视LASIK(主视眼按最佳矫正远视力完全矫正,非主视眼近视者低矫-0.75~-2.00D,远视者过矫0.75~2.00D),35例放弃手术,13例患者双眼全部矫正。观察术后1d;1wk;3mo时的检查结果。结果:术后3mo单眼视LASIK组124例患者双眼远视力0.7~1.2,双眼近视力J1~J3。无因为难以耐受的不适而需要戴镜补充矫正或再次手术者。双眼完全矫正组术后双眼远视力0.7~1.2,双眼近视力J3~J6,8例(62%)视近困难,需配近用眼镜。结论:单眼视LASIK治疗伴有老视的屈光不正安全有效。单眼视治疗在设计手术方案时需根据患者年龄及调节能力、近附加度数、阅读距离、工作性质等综合考虑。     

Two-year follow-up of conductive keratoplasty for the treatment of hyperopic astigmatism

PURPOSE: To evaluate the safety, efficacy, predictability, and stability of conductive keratoplasty (CK) for the treatment of hyperopic astigmatism. SETTING: University of Crete Medical School, Vardinoyannion Eye Institute of Crete, Heraklion, Greece. METHODS: In this prospective nonrandomized noncontrolled single-center study, 47 eyes of 34 patients (15 women and 19 men) were treated for hyperopic astigmatism (up to + 3.50 diopters [D]) with a Refractec ViewPoint CK system and followed for 24 months +/- 0.6 (SD). The treatment consisted of 4 to 36 spots applied to the periphery of the cornea. Mean age was 48.5 years +/- 9.7 years, range 25 to 68 years. All the treated eyes were analyzed for safety, efficacy, predictability, and stability. RESULTS: The mean patient age was 48.5 +/- 9.7 years (range 25 to 68 years). Preoperatively, the mean manifest refraction spherical equivalent (MRSE) was +2.11 +/- 0.88 D (range -0.50 to + 4.13 D); at 12 months, it was -0.52 +/- 0.73 D and at 24 months, -0.50 +/- 0.77 D. At 24 months, the mean MRSE was within +/-0.50 D in 61% of eyes, within +/-1.00 D in 83%, and within +/-2.00 D in all eyes. At 24 months, the uncorrected visual acuity was 20/20 or better in 37% of eyes and 20/40 or better in 97%. By the end of the follow-up period, no eye had lost > or =2 Snellen lines or had an induced cylinder > or =1.50 D. CONCLUSIONS: Conductive keratoplasty for low hyperopic astigmatism was a safe, effective, and stable procedure. Nomogram adjustments and careful patient selection should contribute to higher levels of predictability when treating hyperopic astigmatism.     

Two-year results of conductive keratoplasty for the correction of low to moderate hyperopia

PURPOSE: To evaluate the 2-year postoperative safety, efficacy, predictability, and stability results of conductive keratoplasty (CK) to correct low to moderate hyperopia. SETTING: Department of Ophthalmology, Stanford University Medical Center, Stanford, California, USA. METHODS: In a prospective nonrandomized noncontrolled trial, 25 eyes of 14 patients with +0.75 to +3.00 diopters (D) of hyperopia and 相似文献   

Diode laser thermal keratoplasty to correct hyperopia

PURPOSE: We investigated long-term efficacy, predictability, stability, and safety of diode laser thermal keratoplasty (DTK) to correct hyperopia. METHODS: DTK was performed on 24 eyes (18 patients). Eight eyes with high hyperopia (mean +4.75 +/- 0.63 D; range +3.50 to +5.50 D) received 12 pairs of coagulation spots at 6-mm and 7-mm treatment zone diameters; eight eyes with low hyperopia (mean +2.25 +/- 0.40 D; range +1.50 to +2.75 D) received eight coagulation spots at 8 mm, and eight eyes with low hyperopia (mean +1.50 +/- 0.46 D; range +1.25 to +2.25 D) were treated to induce mild myopia (-1.50 D) in the non-dominant eye for monovision using eight pairs of spots at 7 and 8-mm diameters. Minimum follow-up was 18 months. RESULTS: Mean decrease in cycloplegic refraction at 18 months was 5.00 +/- 0.38 D in the high hyperopia group, 1.75 +/- 0.19 D in the low hyperopia group, and 3.25 +/- 0.27 D in the presbyopia group. Mean increase in uncorrected visual acuity (UCVA) at 18 months was 8.125 +/- 2.1 Snellen lines in the high hyperopia group, 6.625 +/- 0.744 lines for low hyperopia; decrease of 1.00 +/- 1.85 line occurred in the presbyopia group. Near UCVA in the presbyopia group improved by 3.875 +/- 0.83 Jaeger lines. Best spectacle-corrected visual acuity (BSCVA) was restored by 3 months in all eyes. CONCLUSION: DTK was an effective and fairly safe procedure, with reasonable predictability and stability. Nomograms for laser energy level, treatment zone diameter, and number of spots need improvement.     

准分子激光原位角膜磨镶术治疗远视眼老视的临床观察

目的 探讨准分子激光原位角膜磨镶术(LASIK)治疗远视眼老视的临床效果.方法 回顾性病例分析研究.收集32例(64只眼)因远视眼老视行LASIK患者的资料.术前屈光度数:球镜为+0.75～+3.00 D,柱镜为0.00～+1.75 D.术后预期目标屈光度数:主视眼为0.00～-0.50 D视远,非主视眼为-1.50～-2.50 D视近,目标近视力等于或高于J3.术后随访时间12个月,观察术后双眼裸眼远近视力、角膜形态、屈光度数及对比敏感度等.本研究采用t检验、X2检验、SNK-q检验方法对数据进行统计学分析.结果 LASIK术后12个月双眼裸眼远视力≥0.8且近视力等于或高于J3及等于或高于J4的患者分别为53.1%(17/32)及87.5%(28/32).术后不同时间角膜屈光力较术前[角膜直径3 mm区域为(44.12±1.38)D、5 mm区域为(43.42±1.53)D]均有明显增加,且对应的角膜非球面参数Q值,如主视眼术后1、3、 6、 12个月分别为-0.514±0.053、-0.416±0.065、-0.389±0.076、-0.368±0.087,亦呈负值增加(t=19.25,12.14,9.82,8.11;P<0.01).术后12个月等效球镜屈光度数与预期目标差值在±0.50 D和±1.00 D以内者主视眼分别为87.5%(28/32)、100.0%(32/32),非主视眼分别为56.2%(18/32)、90.6%(29/32).术后6个月双眼各空间频率对比敏感度与术前比较,差异均无统计学意义(t:0.63,0.45,0.37,1.06,0.64;P0.05);术后12个月主诉有干眼症状的患者占15.6%(10/23),满意度调查84.4%(27/32)患者对疗效满意.结论 根据单眼视原理采用LASIK治疗远视眼老视可获得较好的临床效果,但其远期疗效和稳定性有待进一步观察.     

Wavefront-guided laser in situ keratomileusis retreatment for consecutive hyperopia and compound hyperopic astigmatism

PURPOSE: To evaluate the efficacy, predictability, and safety of wavefront-guided laser in situ keratomileusis (LASIK) using the Visx CustomVue excimer laser (Advanced Medical Optics) in eyes with consecutive hyperopia and compound hyperopic astigmatism after LASIK. SETTING: Stanford University School of Medicine, Department of Ophthalmology, Stanford, California, USA. METHODS: This retrospective analysis included 19 eyes of 16 patients who had wavefront-guided LASIK for consecutive hyperopia and compound hyperopic astigmatism after initial LASIK surgery. Primary outcome variables, including uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), higher-order aberration (HOA) analysis, and spherical equivalence, were evaluated at 1 and 3 months. Nine eyes of 7 patients were available for all visits. RESULTS: The mean patient age was 51.7 years +/- 3.77 (SD) (range 44 to 55 years). The mean preoperative manifest refractive spherical equivalent (MRSE) was 0.99 +/- 0.32 diopters (D) (range 0.50 to 1.50 D) and the mean 3-month postoperative MRSE, -0.04 +/- 0.66 D (range -1.50 to 0.75 D). At 1 month, 57.9% of eyes had a UCVA of 20/20 or better and 78.9% of 20/25 or better; 84.2% were within +/-1.00 D of emmetropia. At 3 months, 66.7% of eyes had a UCVA of 20/20 or better and 88.9% of 20/25 or better; 88.9% were within +/-1.00 D of emmetropia. No eye lost 2 or more lines of BSCVA at 1 or 3 months. CONCLUSION: Wavefront-guided LASIK was an effective, predictable, and safe procedure for consecutive hyperopia and compound hyperopic astigmatism after LASIK.     

Conductive keratoplasty for the correction of low to moderate hyperopia: 1-year results on the first 54 eyes

OBJECTIVE: To document the 1-year postoperative clinical results of the safety, efficacy, and stability of conductive keratoplasty (CK) to correct low to moderate hyperopia. DESIGN: Prospective, nonrandomized, self-controlled trial. PARTICIPANTS: Five surgeons at four centers performed CK on the first 54 eyes of a multicenter, 2-year clinical trial. Treated eyes had +0.875 to +4.00 diopters (D) of hyperopia and < or =0.75 D of cylinder. The nature of this procedure was explained to all participating patients who signed informed consent forms prior to undergoing the procedure. INTERVENTION: Low energy, high-frequency current was applied directly into the peripheral corneal stroma through a delivery tip inserted at 16 or more treatment spots. An early nomogram was used for the first 54 eyes with an intended refraction of plano. MAIN OUTCOME MEASURES: Data from all 54 eyes were analyzed for safety and stability. A subset of 30 of the 54 eyes was found that had been treated with the appropriate number of spots with the early nomogram. These eyes were categorized as current nomogram eyes; the data for these eyes were analyzed for efficacy and predictability, as well as stability and safety. All patients reported on satisfaction and quality of vision after surgery. RESULTS: Preoperatively, the manifest refractive spherical equivalent refraction (MRSE) of the 30 current nomogram eyes was +1.57 D. At 1 year postoperatively, uncorrected visual acuity was 20/20 or better in 57% of the eyes and 20/40 or better in 93%. The MRSE was within 0.50 D in 46%, within +/-1.00 D in 93%, and within +/-2.00 D in 100%. No eye lost > or =2 lines of best spectacle-corrected visual acuity at 1 year postoperatively nor had an induced cylinder of > or =2.00 D. The MRSE changed a mean of 0.25 D +/- 0.43 between 3 and 6 postoperative months, 0.16 D +/- 0.38 between 6 and 9 postoperative months, and 0.07 D +/- 0.38 between 9 and 12 postoperative months. Refractive stability appeared to be attained by 6 months postoperatively. CONCLUSIONS: Conductive keratoplasty appears to be safe, effective, and stable for correcting low to moderate spherical hyperopia. Stability appeared by the 6-month follow-up visit. For the eyes treated with the current CK nomogram, uncorrected visual acuity, predictability, and stability are as good as or better than those obtained with hyperopic laser in situ keratomileusis or noncontact laser thermal keratoplasty.     

Long-term results of conductive keratoplasty for low to moderate hyperopia

PURPOSE: To assess the long-term safety, efficacy, predictability, and stability of conductive keratoplasty (CK) for the treatment of low to moderate hyperopia and to evaluate the impact of the procedure on the quality of vision. SETTING: University of Crete, Medical School, Vardinoyannion Eye Institute of Crete, Crete, Greece. METHODS: In this prospective nonrandomized noncontrolled single-center study, 38 eyes of 26 patients (13 women and 13 men) were treated for hyperopia with a Refractec ViewPoint CK system and followed for 30 months. Preoperatively, the mean manifest refraction spherical equivalent (MRSE) was +1.89 diopters (D) +/- 0.6 (SD) (range +1.00 to +3.25 D), and the mean follow-up was 30.9 +/- 1.1 months. All eyes were treated with the regular CK nomogram for the treatment of spherical hyperopia. The treatment consisted of 8 to 32 spots applied to the periphery of the cornea. Mean age was 50.3 +/- 8.8 years (range 31 to 71 years). All treated eyes were analyzed for safety, efficacy, predictability, and stability. RESULTS: At 12 months, the MRSE was -0.06 +/- 0.8 D and at 30 months was -0.02 +/- 0.7 D. At 30 months, the mean MRSE was within +/-0.50 D in 68%, within +/-1.00 D in 92%, and within +/-2.00 D in all eyes. At 30 months, uncorrected visual acuity was 20/20 or better in 52.5% and 20/40 or better in 89% of eyes. No eye lost 2 or more Snellen lines or had an induced cylinder of 2.00 D or greater. The procedure did not cause statistically significant changes in contrast sensitivity. CONCLUSION: Results show that CK for low to moderate hyperopia is a safe, effective, predictable, and stable procedure.     

Laser in situ keratomileusis for spherical hyperopia and hyperopic astigmatism using the NIDEK EC-5000 excimer laser

PURPOSE: To assess the efficacy, predictability, and safety of LASIK for the surgical correction of low to moderate hyperopia and hyperopic astigmatism using the NIDEK EC-5000 excimer laser. METHODS: In a multicenter United States Food and Drug Administration (FDA) regulated study of LASIK, 7 centers enrolled 293 eyes with manifest refraction sphere that ranged from +0.50 to +6.00 diopters (D) with or without astigmatism up to 3.00 D. The intended outcome was plano in all eyes. Patients were treated bilaterally. One year postoperative outcomes are reported. RESULTS: The mean spherical equivalent refraction (MRSE) for all eyes changed from +2.61 +/- 1.19 D (range: +0.50 to +6.63 D) preoperatively to +0.35 +/- 0.54 D (range: -1.63 to +2.00 D) 1 year postoperatively. Overall, 61% (170/279) of eyes achieved distance uncorrected visual acuity (UCVA) of 20/20 or better, 82% (228/279) of eyes saw 20/25 or better, and 99% (277/279) of eyes saw 20/40 or better. Refractive accuracy was demonstrated as 63.1% (176/279) of eyes achieved a MRSE within +/- 0.50 D and 90.3% (252/279) of eyes within +/- 1.00 D. Less than 2% (4/279) of eyes lost 2 lines of distance best spectacle-corrected visual acuity. Stability of refraction was demonstrated by 6 months, with a mean hyperopic shift of < 0.03 D from 3 to 6 months. CONCLUSIONS: The NIDEK EC-5000 corrected hyperopia and hyperopic astigmatism with UCVA, refractive accuracy, 1-year stability, and safety that surpassed all FDA criteria.     

CustomVue laser in situ keratomileusis treatment after previous keratorefractive surgery

PURPOSE: To evaluate the efficacy, predictability, and safety of Visx CustomVue wavefront-guided enhancement after previous keratorefractive surgery. SETTING: Stanford University Eye Laser Center, Stanford, California, USA. METHODS: A retrospective analysis was used to evaluate wavefront-guided enhancement in a preliminary set of 120 eyes of 102 patients. All eyes had previous keratorefractive surgery (photorefractive keratoplasty [PRK] in 1 eye, laser in situ keratomileusis [LASIK] in 119 eyes); the prekeratorefractive surgery spherical equivalent (SE) refraction ranged from -1.25 diopters (D) to -7.00 D. Primary outcome variables including uncorrected visual acuity (UCVA), manifest refraction, and complications were evaluated at 1 and 3 months. RESULTS: At 1 month, the mean pre-enhancement SE was reduced from -0.91 D +/- 0.40 (SD) (range -2.375 to -0.125 D) to -0.13 +/- 0.33 D (range -1.25 to 0.75 D) with 91% of eyes within +/-0.5 D of emmetropia and 100% within +/-1.0 D. All eyes showed equal or improved UCVA (range 20/15 to 20/30) with 20/20 or better in 84 of 91 eyes. At 3 months, the mean was -0.20 +/- 0.32 D (range -0.75 to 0.75 D) with 100% of eyes within +/-0.75 D of emmetropia. All eyes showed equal or improved UCVA (range 20/15 to 20/30) with 20/20 or better in 74 of 84 eyes. Higher-order wavefront aberration analysis showed that the mean root-mean-square error was reduced from 0.39 +/- 0.14 microm (range 0.16 to 0.86 microm) to 0.34 +/- 0.12 microm (range 0.12 to 0.78 microm). Coma was reduced from 0.22 +/- 0.13 microm (range 0.02 to 0.71 microm) to 0.16 +/- 0.11 microm (range 0.01 to 0.62 microm), and trefoil was reduced from 0.16 +/- 0.09 microm (range 0.01 to 0.62 microm) to 0.11 +/- 0.07 microm (range 0.01 to 0.27 microm). Spherical aberration was unchanged from 0.14 +/- 0.14 microm (range -0.18 to 0.59 microm) to 0.14 +/- 0.14 microm (range -0.16 to 0.5 microm). CONCLUSION: Preliminary data show that Visx CustomVue wavefront-guided enhancement after keratorefractive surgery is an effective, predictable, and safe procedure.     

Refractive lens exchange with an array multifocal intraocular lens

PURPOSE: To prospectively evaluate safety, efficacy, predictability, stability, complications, and patient satisfaction after refractive lens exchange (clear lens extraction) followed by posterior chamber implantation of a multifocal intraocular lens (IOL). METHODS: Fifty eyes of 25 patients (mean age 51 years, range 44 to 62 years) with preoperative spherical equivalent refraction between -15.50 and +5.75 D and cylinder between 0 and 1.50 D underwent bilateral implantation of a zonal progressive multifocal IOL (Array, AMO). RESULTS: Eyes were divided into group A (n=24; myopia, average preoperative spherical equivalent refraction -7.11 +/- 3.25 D (-1.75 to -15.50 D), and group B (n=26; hyperopia, average preoperative spherical equivalent refraction +3.04 +/- 1.04 D). Follow-up was 6 months in all eyes. Postoperatively, all eyes of both groups were within +/-1.00 D of target refraction. No eye in group A and three eyes in group B sustained a loss of one line of BSCVA. Forty-seven eyes (94%) remained unchanged or gained one or more lines of their preoperative BSCVA. In all eyes, postoperative UCVA was 20/40 or better. When compared to preoperative, uncorrected near visual acuity improved (statistically significant). All patients achieved uncorrected binocular visual acuity of 20/30 and J4 or better. Patient satisfaction was extremely high; no intra- or postoperative complications were reported. CONCLUSION: Six-month results of implantation of the AMO Array multifocal IOL for refractive lens exchange demonstrated safety, efficacy, and predictability in correcting high ametropia and significant improvement of uncorrected near and distance visual acuity.     

Intraocular Lens Multifocality Combined with the Compensation for Corneal Spherical Aberration: A New Concept of Presbyopia-Correcting Intraocular Lens

The outcomes of a prospective consecutive study aimed at evaluating the visual and refractive benefit after cataract surgery with the implantation of the aspheric diffractive multifocal intraocular lens (IOL) Tecnis ZMB00 (Abbott Medical Optics) are reported. A total of 31 eyes of 19 patients (age range, 40 to 81 years) underwent phacoemulsification surgery with implantation of this aspheric multifocal IOL. At 6 months after surgery, postoperative spherical equivalent was within ±1.00 D in 96.8% of eyes, with 94.7% of patients presenting a postoperative binocular far LogMAR uncorrected visual acuity (UCVA) of 0.1 or better. Far best-corrected distance VA improved significantly (p < 0.01), with postoperative values of 0.1 or better in 96.8% of eyes. Postoperative near UCVA was 0.10 (equivalent to J1) or better in 93.55% of eyes. Furthermore, the IOL power was found to be very poorly correlated with the postoperative far LogMAR (r = 0.13) and near UCVA (r = 0.13). In conclusion, the aspheric diffractive multifocal IOL Tecnis ZMB00 provides a restoration of the far and near visual function after phacoemulsification surgery for cataract removal or presbyopia correction, which is predictable and independent from the optical power of the implanted IOL.Key words: Diffractive intraocular lens, Multifocal intraocular lens, Tecnis, Spherical aberration