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Alexandra E Karavitaki, Ioannis G Pallikaris, Sophia I Panagopoulou, George A Kounis, George Kontadakis, George D KymionisInstitute of Vision and Optics, University of Crete, Crete, GreecePurpose: Our purpose was to evaluate the long-term visual outcomes after bilateral implantation of Crystalens® HD (Bausch and Lomb, Inc.) accommodative intraocular lenses.Methods: In this study, 25 patients (50 eyes) who underwent cataract surgery and bilateral Crystalens HD accommodative intraocular lens implantation were included. The Crystalens HD lens was implanted in the bag in both eyes, without any intra- or postoperative complications. The visual parameters measured before and after surgery were: uncorrected distance visual acuity, corrected distance visual acuity (CDVA) (using the Early Diabetic Retinopathy Study [EDTRS] logMAR charts), uncorrected intermediate visual acuity, and uncorrected near visual acuity using a Birkhäuser reading chart, at a distance of 66 cm and 33 cm for intermediate and near vision, respectively, directly illuminated by a lamp of 60 watts. After surgery, the patients were evaluated at 1, 3, 6, 12, 24, and 36 months.Results: The mean age was 68.70±7.1 (range: 54 to 83) years. The mean follow-up was 42.72±0.49 (range: 42.33 to 43.27) months. The uncorrected distance visual acuity improved from 0.56±0.41 (range: 0 to 2) preoperatively to 0.19±0.13 (range: 0 to 0.38) (logMAR scale) at the last follow-up visit, and the CDVA improved from 0.17±0.18 (range: 0 to 0.7) preoperatively to 0.05±0.05 (range: −0.02 to 0.22) at the last follow-up visit. No eyes lost lines of CDVA during the follow-up period, while 54% of patients gained one or more lines of CDVA. The uncorrected intermediate and near visual acuity was J2 or better in 71% and 69% of our patients, respectively.Conclusion: Crystalens HD implantation seems to provide an improvement in visual acuity for far, intermediate, and near distances.Keywords: presbyopia, accommodation

Purpose: To evaluate the effect of corneal crosslinking (CXL) with ultraviolet A (UVA) irradiation on pupil response to tropicamide 0.5% instillation., Methods: This prospective interventional study enrolled 17 patients (19 eyes) with progressive keratoconus who underwent CXL with UVA irradiation. Central corneal thickness (CCT) was evaluated with the use of anterior segment optical coherence tomography (Visante OCT 3.0). Pupil diameter was measured with the use of Colvard infrared pupillometer before the instillation of tropicamide 0.5% and after the instillation of tropicamide every 5 minutes for total duration of 30 minutes. Corneal epithelial integrity was examined with the use of fluorescein dye staining. Measurements were performed 1 day preoperatively and 1 month postoperatively, with emphasis on simulating the same light conditions regarding the pupil measurements., Results: No intraoperative or postoperative complications were observed in any of the patients. Mean CCT decreased significantly (p<0.001) 1 month postoperatively. Mean postoperative pupil size did not change significantly at any time point compared to the mean preoperative measurements., Conclusions: The CXL procedure seems not to impair effectiveness of topical drugs, using pupil size measurements after tropicamide 0.5% instillation.

Purpose of Review: The aim of this review is to offer a comprehensive overview of the different PresbyLASIK approaches, which have been published in peer-reviewed journals., Recent Findings: Comprehensive search was conducted in scopus using keywords presbyLASIK, presbyopia, LASIK, corneal multifocality. We reviewed binocular uncorrected and corrected distance and near visual acuity, and loss of lines of best corrected visual acuity, for presbyopic patients among three different basic treatment modalities., Summary: Additional trials and standards for reporting results for presbyopic approaches are necessary. Careful patient selection and counseling is imperative in all PresbyLASIK treatments.

Purpose. To present a case of cataract surgery performed in a patient with a refractive corneal inlay in place. Methods. A 48-year-old female patient presented to our institute with bilateral cataract. The patient had undergone refractive corneal inlay implantation three years ago in her right, nondominant eye for presbyopia correction. Biometry and intraocular lens (IOL) power calculation were performed without removing the inlay. Phacoemulsification and IOL insertion were carried out in both eyes in a usual manner. Results. On day one postoperatively, the patient achieved binocular uncorrected distance visual acuity 20/20 and uncorrected near visual acuity J1. The vision remained stable during the one-year follow-up period. Conclusion. Cataract surgery was performed in a standard manner in a patient with Presbia Microlens corneal inlay in place. Visual outcomes for both near and distance vision were satisfactory.

Unlabelled: We present the case of a patient who had refractive corneal inlay implantation for near vision improvement after bilateral cataract surgery. The patient had a history of bilateral cataract, and a 2-step procedure was suggested to improve her near and distance visual acuities. The first step was bilateral cataract extraction with a power target of plano intraocular lens implantation. Six months later, a refractive corneal inlay, Presbia Microlens, was implanted in the nondominant eye in the intracorneal pocket made with the femtosecond laser. No intraoperative or postoperative complications occurred. The bilateral uncorrected near visual acuity improved from less than Jaeger (J)6 to J1 and remained stable during the 2-year follow-up. The refractive corneal inlay is a safe, simple, and efficient method for improving near visual acuity in patients after cataract surgery., Financial Disclosure: Dr. Pallikaris is the chair of the medical advisory board of Presbia Coöperatief U.A. No other author has a financial or proprietary interest in any material or method mentioned., (Copyright © 2014 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate the outcomes after Wichterle Intraocular Lens-Continuous Focus (Medicem, Kamenné Zehrovice, Czech Republic) accommodative bioanalogic intraocular lens implantation., Methods: In this prospective case series, 50 eyes of 25 patients (mean age: 65.3 ± 8.4 years; range: 53 to 83 years) were included. All patients underwent routine cataract surgery and Wichterle Intraocular Lens-Continuous Focus implantation., Results: Mean follow-up was 11.44 ± 2.46 months (range: 9 to 17 months). Both monocular uncorrected and corrected distance visual acuity statistically and significantly (P < .05) improved from 0.31 ± 0.17 (20/63 Snellen) (range: counting fingers to 0.7) to 0.74 ± 0.19 (20/25 Snellen) (range: 0.2 to 1) and from 0.61 ± 0.19 (20/32 Snellen) (range: 0.2 to 1) to 0.82 ± 0.13 (20/25 Snellen) (range: 0.4 to 1), respectively. Target postoperative refraction was -0.5 diopters (D) and preoperative and 1-year postoperative spherical equivalent refraction were 0.72 ± 2.71 D (range: -7.25 to 2.37 D) and -0.24 ± 0.65 D (range: -1.0 to 1.0 D), respectively. No eyes lost lines of corrected distance visual acuity during the follow-up period, whereas 88% of patients gained one or more lines of corrected distance visual acuity. Uncorrected intermediate and near visual acuity were J2 (Snellen 20/25) or better in 72% of patients. No complications occurred intraoperatively or postoperatively. The evaluation of the mean values of root mean square of third and fourth order higher-order aberrations at 1 year postoperatively revealed a mean negative spherical aberration of -0.18 ± 0.13 μm., Conclusions: Wichterle Intraocular Lens-Continuous Focus accommodative bioanalogic IOL implantation provides satisfactory visual acuity for far, intermediate, and near distances and the promising results remain stable throughout the follow-up period., (Copyright 2014, SLACK Incorporated.)

Purpose: To describe a new minimally invasive surgical technique for the symptomatic management of bullous keratopathy in blind eyes., Methods: Four patients with severe corneal edema due to endothelial decompensation and no visual function in the affected eye presented for the relief of their ocular symptoms (pain and tearing). Femtosecond laser technology was used to create a deep corneal pocket into which silicone oil was inserted., Results: After the procedure, all patients demonstrated immediate relief of their symptoms, along with restoration of a normal corneal surface 7 days after the procedure (no bullae and no epithelial defects). All patients remained free of symptoms during the entire follow-up period (from 24 to 31 months). Anterior to the inserted implant, the corneal lamellae remained compact, transparent, and without bullae; whereas the posterior corneal stroma under the implant was edematous. No intraoperative or postoperative complications were noted., Conclusions: Intracorneal insertion of silicone oil is a feasible new technique for the symptomatic treatment of bullous keratopathy in blind eyes.

Purpose: To evaluate the results of thin-flap laser in situ keratomileusis (LASIK) using a femtosecond-laser platform for flap creation., Setting: Institute of Vision and Optics, Faculty of Medicine, University of Crete, Heraklion, Greece., Design: Prospective interventional case series., Methods: Patients had LASIK with the FS200 femtosecond laser for flap creation and the Allegretto Wave Eye-Q excimer laser. Flap thickness was set at 105 μm. All eyes were examined 1 month postoperatively. Flap thickness was assessed with anterior segment optical coherence tomography using the manual flap tool at 5 locations on a horizontal B scan., Results: This study comprised 50 eyes of 25 patients (mean age 28 years ±5.72 [SD]); 42 eyes completed 6 months of follow-up. Preoperatively, the mean sphere was -3.61 ± 1.87 diopters (D) and the mean cylinder, -1.08 ± 1.23 D. Six months postoperatively, no eye lost lines of corrected distance visual acuity (CDVA), 29% gained 1 line, and 7% gained 2 lines. The mean spherical equivalent was -0.03 ± 0.42 D (range -0.88 to +0.88 D); 86% had an uncorrected distance visual acuity of 20/20 or better. The mean central flap thickness at 1 month was 102.98 ± 6.33 μm (range 91 to 114 μm). There were no intraoperative or postoperative complications., Conclusions: No significant complications occurred after treatment with this new femtosecond-laser platform in thin-flap LASIK. Clinical (visual and refractive) results were satisfactory in terms of safety, predictability, and stability., (Copyright © 2013 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate the outcomes and safety of a refractive inlay (Flexivue Micro-Lens, Presbia Coöperatief U.A.) for the corneal compensation of presbyopia., Methods: This prospective, interventional clinical study comprised 47 emmetropic presbyopes with a mean age of 52±4 years (range: 45 to 60 years). The inlay was inserted, centered on the line of sight, inside a corneal pocket created in the patient's nondominant eye, using a femtosecond laser. Follow-up was 12 months. Visual acuity, corneal topography, wavefront aberrometry, contrast sensitivity, structural corneal alterations, and questionnaires were evaluated., Results: Twelve months after surgery, uncorrected near visual acuity was 20/32 or better in 75% of operated eyes, whereas mean uncorrected distance visual acuity (UDVA) of operated eyes was statistically significantly decreased from 0.06±0.09 logMAR (20/20) (range: -0.08 to 0.26) preoperatively to 0.38±0.15 logMAR (20/50) (range: 0.12 to 0.8) (P<.001), and mean binocular UDVA was not significantly altered (P=.516). Seventeen patients lost one line of corrected distance visual acuity in the operated eye. No patient lost 2 lines in CDVA in the operated eye. Overall, higher order aberrations increased and contrast sensitivity decreased in the operated eye. No tissue alterations were found using corneal confocal microscopy. No intra- or postoperative complications occurred., Conclusions: Twelve months after implantation, the Flexivue Micro-Lens intracorneal refractive inlay seems to be an effective method for the corneal compensation of presbyopia in emmetropic presbyopes aged between 45 and 60 years old., (Copyright 2013, SLACK Incorporated.)

Purpose: To compare the outcomes of corneal collagen cross-linking (CXL) for the treatment of progressive keratoconus using 2 different techniques for epithelial removal: transepithelial phototherapeutic keratectomy (t-PTK) versus mechanical epithelial debridement., Design: Prospective, comparative, interventional case series., Participants: Thirty-four patients (38 eyes) with progressive keratoconus were enrolled., Methods: All patients underwent uneventful CXL treatment. Sixteen patients (19 eyes) underwent epithelial removal using t-PTK (group 1) and 18 patients (19 eyes) underwent mechanical epithelial debridement using a rotating brush (group 2) during CXL treatment. Visual and refractive outcomes were evaluated along with corneal confocal microscopy findings preoperatively and at 1, 3, 6, and 12 months postoperatively., Main Outcome Measures: Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction, and keratometry readings., Results: No intraoperative or postoperative complications were observed in any of the patients. In group 1, logarithm of the minimum angle of resolution mean UDVA and mean CDVA improved from 0.99 ± 0.71 and 0.30 ± 0.26 preoperatively to 0.63 ± 0.42 (P = 0.02) and 0.19 ± 0.18 (P = 0.008) at 12 months postoperatively, respectively. In group 2, neither mean UDVA nor mean CDVA demonstrated a significant improvement at 12 months postoperatively (P>0.05). In group 1, mean corneal astigmatism improved from -5.84 ± 3.80 diopters (D) preoperatively to -4.31 ± 2.90 D (P = 0.015) at the last follow-up, whereas in group 2 there was no significant difference at the same postoperative interval (P>0.05). No endothelial cell density alterations were observed throughout the follow-up period for both groups (P>0.05)., Conclusions: Epithelial removal using t-PTK during CXL results in better visual and refractive outcomes in comparison with mechanical epithelial debridement., (Copyright © 2012 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate the results after unilateral sulcus implantation of the Crystalens HD (Bausch & Lomb) accommodative intraocular lens (IOL)., Methods: This retrospective interventional case series comprised six eyes from three patients who underwent cataract surgery and bilateral Crystalens HD accommodative IOL implantation. The Crystalens HD was implanted in the bag in one eye (non-sulcus group) and, due to posterior capsule rupture, the lens was positioned in the ciliary sulcus in the fellow eye (sulcus group)., Results: Mean patient age was 66.3 ± 4.9 years (range: 60 to 72 years). Mean follow-up was 14.3 ± 3.2 months (range: 12 to 18 months) for the non-sulcus group and 14 ± 2 months (range: 12 to 16 months) for the sulcus group. Uncorrected distance visual acuity improved from 20/100 to 20/33 in the non-sulcus group and from 20/63 to 20/32 in the sulcus group during last follow-up. Corrected distance visual acuity improved from 20/35 to 20/20 in the non-sulcus group and from 20/27 to 20/23 in the sulcus group. Regarding near vision, all eyes in the sulcus group and 66.7% of eyes in the non-sulcus group achieved J1-J2 (Birkhauser reading chart). None of the eyes had any intra- (except posterior capsule rupture in the sulcus cases) or postoperative complications., Conclusions: Based on this small series, ciliary sulcus implantation of the Crystalens HD seems to be associated with no significant morbidity and provides satisfactory visual acuity outcomes., (Copyright 2012, SLACK Incorporated.)

Purpose: To investigate the outcomes and safety of an intrastromal refractive inlay (Invue Lens, Biovision AG) for the corneal compensation of presbyopia., Methods: This prospective, noncomparative, interventional clinical study comprised 45 emmetropic presbyopes with a mean age of 52.3 ± 3.3 years (range: 47 to 58 years). The refractive inlay was inserted in the non-dominant eye within a corneal pocket that was created using a mechanical microkeratome. Last follow-up was 12 months in all patients and examinations were scheduled at 1 week and 1, 3, 6, and 12 months after surgery. Visual, wavefront, contrast sensitivity, and topographic outcomes as well as structural corneal alteration were evaluated., Results: Twelve months after surgery, uncorrected near visual acuity was 20/32 or better in 98% of operated eyes and binocularly, whereas uncorrected distance visual acuity was 20/40 or better in 93% of operated eyes and 20/25 or better in all patients binocularly. Three patients lost one line of corrected distance visual acuity in the operated eye. Overall, higher order aberrations were increased and contrast sensitivity was decreased in the operated eye. No tissue alterations were found using corneal confocal microscopy. No intra- or postoperative complications occurred., Conclusions: The intracorneal refractive inlay (Invue Lens) seems to be an effective surgical method for the corneal compensation of presbyopia in emmetropes aged between 45 and 60 years., (Copyright 2012, SLACK Incorporated.)

Purpose: To evaluate the long-term results of phakic refractive lens (PRL; Carl Zeiss Meditec) implantation in eyes with high myopia., Methods: In this retrospective, noncomparative, interventional case series, 143 myopic eyes of 82 patients were treated for high myopia with the implantation of the silicone PRL in the posterior chamber., Results: Mean follow-up was 3.8±1.7 years (range: 1 to 6 years). Six years postoperatively (n=34), a statistically significant reduction was noted in the cycloplegic spherical equivalent from -14.08±4.00 diopters (D) (range: -24.88 to -4.75 D) before PRL implantation to -0.45±0.62 D (range: -1.00 to 1.00 D) (P<.001). At 6 years, 67.6% (23 eyes) and 91.2% (31 eyes) were within ±0.50 and ±1.00 D of target refraction, respectively. Mean logMAR uncorrected and corrected distance visual acuity improved significantly (P<.001) (counting fingers preoperatively in all eyes to 0.17±0.15 [range: 0.54 to -0.06] and 0.19±0.19 [1.00 to -0.08] to 0.07±0.10 [range: 0.30 to -0.10], respectively). Complications included anterior capsule damage (3 eyes), temporary intraocular pressure increase (14 eyes), pigment dispersion (1 eye), and PRL decentration (1 eye). No eyes presented any signs of cataract up to 6 years postoperatively., Conclusions: Long-term results show that PRL implantation is an effective and safe method for treating high myopia., (Copyright 2011, SLACK Incorporated.)

Purpose: To report a case of interface corneal stromal irregularities after flap creation with the advanced IntraLase femtosecond (150 Hz) laser system (Abbott Medical Optics, Inc.)., Methods: Case report., Results: An 18-year-old man underwent bilateral laser in situ keratomileusis (LASIK) using the IntraLase femtosecond laser to create 110-µm flaps. The procedure was uneventful in the left eye. In the right eye, after flap lifting a central irregular stromal interface was noted. The created flap was thicker than expected (139 µm) as measured intraoperatively with ultrasound pachymetry. The excimer laser ablation procedure was performed and the flap was repositioned. On the first postoperative day and during the 6-month follow-up period, uncorrected distance visual acuity was 20/20 in both eyes., Conclusions: Interface corneal stromal irregularities may occur after femtosecond corneal flap creation during LASIK.

A thirty-nine year old man was referred to our institute due to progressive decreased visual acuity five years after bilateral Laser in situ Keratomileusis (LASIK). Topography revealed signs of post - LASIK ectasia. Patients' left eye was treated with simultaneous Topography Guided Photorefractive Keratectomy (PRK) followed by Corneal Collagen Cross Linking (CXL). Twelve months after the combined procedure both uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA) showed significant improvement while topographic findings revealed an improvement of the astigmatic pattern. All higher order aberrations showed a significant decrease twelve months postoperatively. Combined topography guided PRK and corneal cross linking could represent an alternative treatment for post - LASIK ectasia.

Purpose: to present a patient in whom, during LASIK with the IntraLase femtosecond laser (Abbott Medical Optics), unintended epithelial (instead of anterior stromal) flaps were created in both eyes., Methods: a 28-year-old man underwent bilateral LASIK using the IntraLase femtosecond laser programmed to create 100-microm flaps. Flap creation was performed uneventfully in both eyes but flap thickness was thinner than attempted. The flaps were easily torn during flap lift because they appeared to consist of epithelium only. Therefore, the procedure was immediately converted to photorefractive keratectomy with the use of mitomycin C., Results: re-epithelialization occurred 3 days after the procedure in both eyes. Three months after treatment, uncorrected distance visual acuity was 20/25 in the right eye and 20/20 in the left eye with no signs of corneal haze on slit-lamp examination., Conclusions: despite the advantages of the IntraLase femtosecond laser in the creation of a LASIK flap, complications in terms of flap thickness may occur.

Purpose: To evaluate mitomycin C (MMC) aqueous humor concentration after photorefractive keratectomy (PRK)., Methods: In this experimental study, twenty-four eyes of 12 male pigmented rabbits were divided into 4 groups and studied at the Institute of Vision and Optics, Department of Medicine, University of Crete, Greece. Eyes in groups 1 and 2 underwent PRK to correct -5 diopters (D) in a 6-mm optical zone, while sponges soaked with 0.02% MMC were applied on the exposed corneal stroma for 60 and 120 seconds, respectively. Similarly, eyes in groups 3 and 4 underwent PRK to correct -10 D in a 6-mm optical zone, while sponges soaked with 0.02% MMC were applied on the exposed corneal stroma for 60 and 120 seconds, respectively. Aqueous humor was extracted from all rabbit eyes 10 minutes after MMC application and high-performance liquid chromatography was performed immediately to detect and quantify MMC levels., Results: The mean aqueous humor concentration of MMC was 0.23+/-0.03 microg/mL, 0.39+/-0.05 microg/mL, 0.28+/-0.04 microg/mL, and 0.52+/-0.16 microg/mL in groups 1, 2, 3, and 4, respectively. The effect of application time and correction on aqueous humor MMC concentration was significant (p<0.0001 and p=0.019), while the exposure time had a greater impact on aqueous humor MMC concentration when compared with the attempted correction., Conclusions: Both exposure time of MMC on the corneal stroma and the attempted correction was correlated with MMC aqueous humor concentrations.

Purpose: To study the outcomes of LASIK after intended thin flap creation using the SCHWIND Carriazo-Pendular microkeratome with the 90-microm head., Methods: Forty-seven eyes of 26 patients (mean age 28.78+/-6.98 years) underwent LASIK with a superior hinge flap using the 90-microm head of the SCHWIND Carriazo-Pendular microkeratome. Evaluation included flap parameters (thickness, diameter, hinge size), complications, and visual outcome., Results: No intraoperative or early postoperative complications were observed. The mean flap thickness was 79.88+/-6.94 microm (range: 70 to 93 microm). Mean flap diameter was 9.25+/-0.45 mm (range: 8.5 to 11 mm) whereas mean hinge size was 4.63+/-0.66 mm (range: 3 to 6.5 mm). No eye lost lines of best spectacle-corrected visual acuity, and all eyes were emmetropic within one diopter postoperatively., Conclusions: The SCHWIND Carriazo-Pendular microkeratome with the 90-microm head seems to have increased accuracy in intended creation of thin flaps.

Purpose: To compare the early postoperative course and the 1-year clinical results of off-flap Epi-LASIK and Epi-LASIK for the treatment of low and moderate myopia., Design: Pilot double-masked, randomized, comparative study., Participants: Fifty-six patients (112 myopic eyes)., Methods: Epithelium was separated in all eyes with the use of Centurion SES epikeratome (Norwood Abbey EyeCare, Vic, Australia). The first eye treated and surgical method in the first eye were randomized. One eye of each patient underwent standard Epi-LASIK, whereas in the contralateral eye, the epithelial sheet was not retained on the photoablated stroma (off-flap Epi-LASIK eyes). Mean preoperative spherical equivalent was -3.50+/-1.22 diopters (D; range, -1.75 to -6.37 D) in Epi-LASIK eyes and -3.61+/-1.22 D (range, -1.50 to -6.50 D) in off-flap Epi-LASIK eyes (P>0.05, paired Student t test). Excimer laser corneal ablation was performed using the Allegretto 200Hz (Wavelight Laser Technologie AG, Erlangen, Germany). Patients were followed up daily until the epithelial healing was complete and at 1, 3, 6, and 12 months., Main Outcome Measures: Epithelial healing time, subjective pain score, and uncorrected visual acuity (UCVA) were evaluated during the first postoperative days. Uncorrected visual acuity, spherical equivalent refraction, best spectacle-corrected visual acuity, haze scores, and wavefront aberrations were recorded at all subsequent intervals., Results: Time of epithelial healing did not differ significantly in Epi-LASIK and off-flap Epi-LASIK eyes (4.76+/-0.84 days in Epi-LASIK eyes vs. 4.54+/-0.93 days in off-flap Epi-LASIK eyes). No significant difference in UCVA was found after the 2 techniques during the first postoperative days. Subjective pain score was lower in off-flap Epi-LASIK eyes at 2 postoperative hours, whereas no significant difference in pain scores was noted between the 2 techniques at the other intervals. There was no significant difference in spherical equivalent, line gain or loss, haze scores, and higher-order aberrations between Epi-LASIK and off-flap Epi-LASIK eyes at any interval. Uncorrected visual acuity was significantly better in Epi-LASIK eyes only at 6 months (-0.05+/-0.08 in Epi-LASIK eyes vs. 0.00+/-0.07 in off-flap Epi-LASIK eyes). Preoperative wavefront aberrations did not change significantly 1 year after either procedure., Conclusions: Epi-LASIK and off-flap Epi-LASIK had equal visual and refractive results for the treatment of low and moderate myopia in this study., Financial Disclosure(s): Proprietary or commercial disclosure may be found after the references.

Purpose: To evaluate whether photorefractive keratectomy (PRK) for moderate myopia using a solid-state laser with a wavelength of 213 nm alters the corneal endothelial cell density., Setting: University refractive surgery center., Methods: The corneal endothelium was analyzed preoperatively and 1, 6, and 12 months postoperatively using corneal confocal microscopy (modified HRT II with a Rostock Cornea Module, Heidelberg Engineering) in 60 eyes (30 patients). Patients were randomized to have myopic PRK using a 213 nm wavelength solid-state laser (study group) or a conventional 193 nm wavelength excimer laser (control group). Three endothelial images were acquired in each of 30 preoperative normal eyes to evaluate the repeatability of endothelial cell density measurements. Repeated-measures analysis of variance was used to compare the variations in endothelial cell density between the 2 lasers and the changes in endothelial cell density over time., Results: There were no statistically significant differences in sex, age, corneal pachymetry, attempted correction, preoperative endothelial cell density, or postoperative refractive outcomes (uncorrected visual acuity, best spectacle-corrected visual acuity, and spherical equivalent refraction) between the 2 groups (P>.05). The coefficient of repeatability of endothelial cell density was 131 cells/mm(2). The measured endothelial cell count per 1.0 mm(2) did not significantly change up to 1 year postoperatively in either group (both P>.05). No statistically significant difference was found between the 2 groups in any postoperative interval (P>.05)., Conclusion: Photorefractive keratectomy for moderate myopia using a 213 nm wavelength solid-state laser or a conventional 193 nm wavelength excimer laser did not significantly affect corneal endothelial density during the 1-year postoperative period.

Purpose: To report the long-term (11-year) outcomes (stability and complications) of laser in situ keratomileusis (LASIK) in patients with high myopia., Setting: University refractive surgery center., Methods: Seven patients (4 with bilateral treatment and 3 with unilateral treatment) who had myopic LASIK and completed 11 years of follow-up were included in the study., Results: The mean age of the 2 men and 5 women was 41.7 years +/- 6.5 (SD) (range 34 to 50 years). The mean follow-up was 140.18 +/- 6.70 months (range 132 to 150 months). At 11 years, the spherical equivalent error was statistically significantly reduced, from a mean of -12.96 +/- 3.17 diopters (D) (range -19.00 to -10.00 D) before LASIK to a mean of -1.14 +/- 1.67 D (range -4.25 to 1.00 D) after (P<.001). Predictability of postoperative refraction 6 months and 11 years after LASIK showed that 6 eyes (55%) were within +/-1.00 D of intended correction. No late postoperative complications occurred. Five patients (8 eyes, 73%) were satisfied with the final outcome., Conclusions: Laser in situ keratomileusis was moderately predictable in the correction of high degrees of myopia. After the sixth postoperative month, refractive and topographic stability were obtained. No long-term sight-threatening complications occurred during the follow-up period.

Purpose: To evaluate the feasibility, safety, and predictability of correcting high irregular astigmatism in symptomatic eyes with the use of topography-guided photoablation., Methods: In a prospective, non-comparative case series, 16 consecutive symptomatic eyes of 11 patients with small hyperopic and myopic excimer laser optical zones, decentered and irregular ablation after corneal graft, and corneal scars were operated. Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), manifest and cycloplegic refraction, and corneal topography, with asphericity and regularity, were analyzed. LASIK (n = 10) and photorefractive keratectomy (n = 6) were performed using the ALLEGRETTO WAVE excimer laser and T-CAT software (Topography-guided Customized Ablation Treatment; WaveLight Laser Technologie AG, Erlangen, Germany)., Results: In the LASIK group, UCVA improved from 0.81 +/- 0.68 IogMAR (20/130) (range: 0.2 to 2.0) to 0.29 +/- 0.21 logMAR (20/39) (range: 0.1 to 0.7) at 6 months. In the PRK group, mean UCVA improved from 0.89 +/- 0.87 IogMAR (20/157) (range: 0.1 to 2.0) to 0.42 +/- 0.35 logMAR (20/53) (range: 0.1 to 1.0) at 6 months. Best spectacle-corrected visual acuity did not change significantly in either group. One PRK patient lost one line of BSCVA. Refractive cylinder for the LASIK group improved from -2.53 +/- 1.71 diopters (D) (range: -0.75 to -5.75 D) to -1.28 +/- 0.99 D (range: 0 to -2.50 D) at 6 months. Refractive cylinder in the PRK group improved from -2.21 +/- 2.11 D (range: -0.25 to -5.50 D) to -1.10 +/- 0.42 D (range: -0.50 to -1.50 D). Index of surface irregularity showed a decrease from 60 +/- 12 (range: 46 to 89) to 50 +/- 9 (range: 32 to 63) at 6 months in the LASIK group whereas no significant change was noted in the PRK group. Subjective symptoms, such as glare, halos, ghost images, starbursts, and monocular diplopia, were not present postoperatively., Conclusions: Topography-guided LASIK and PRK resulted in a significant reduction of refractive cylinder and increase of UCVA, without a significant loss of BSCVA.

Purpose: To present an alternate method to Zemike decomposition (modal) of wavefront reconstruction using iterative implicit solution to the finite difference equations (zonal)., Methods: Different reconstruction methods, modal and zonal, were compared and the advantages of each method were analyzed., Results: Although the modal or Zemike method allows for quantitative interpretation of some of the aberrations, it is cumbersome for use with fine details and may lead to errors for eyes with keratoconus or other rapidly varying aberration. The zonal method produces a very high-resolution map that can be used for identifying irregular structures., Conclusions: The distinction between the two methods is useful to maintain, and the solution methods are generally different. In practice, both methods are useful and, with modern computers, both zonal and lower-order modal may be calculated rapidly. The difference between the wavefronts derived from the two methods may provide useful insight or interpretation of the infornation.

Purpose: To evaluate the efficacy and safety of implantation of a new posterior chamber phakic refractive lens (PRL, Ciba Vision Surgical) in highly myopic eyes., Setting: Department of Ophthalmology, Medical School, University of Crete, Vardinoyannion Eye Institute of Crete, Crete, Greece., Methods: Thirty-four myopic eyes of 19 patients were treated for high myopia with implantation of a silicone PRL in the posterior chamber. Mean patient age was 29.0 years +/- 7.9 (SD) (range 18 to 44 years). Manifest refraction in spherical equivalent (MR), uncorrected (UCVA) and best corrected (BCVA) visual acuity (decimal scale), intraocular pressure, higher-order aberrations (root-mean-square [RMS] wavefront error measured with a Shack-Hartmann wavefront sensor WASCA analyzer [Carl Zeiss, Meditec]), possible complications, and subjective symptoms were evaluated., Results: Phakic refractive lenses were successfully implanted in all eyes. Mean follow-up was 17.17 +/- 3.76 months (range 12 to 24 months). There was a statistically significant reduction in the MR (from -14.70 D +/- 2.65 D [range -20.75 D to -10.50 D] to -0.61 D +/- 0.89 D [range -2.25 D to 1.00 D]) (P<.001). Twenty-seven (79%) and 15 eyes (44%) were within +/-1.00 D and +/-0.50 D of target refraction, respectively. Mean UCVA significantly improved (from counting fingers to 0.62 +/- 0.28 (range 0.08 to 1.20) (P<.001). Mean BCVA also improved from 0.70 +/- 0.24 (range 0.10 to 1.00) to 0.85 +/- 0.24 (range 0.10 to 1.20) (P<0.001). Overall, there was a mean increase in BCVA of 1.5 +/- 1.5 lines (range loss of 2 lines to gain of 5 lines). There was no statistically significant difference in higher-order aberrations after PRL implantation (pre-PRL RMS: 0.18 microm +/- 0.08 microm [range 0.09 microm to 0.38 microm]; post-PRL RMS: 0.21 microm +/- 0.08 microm; [range 0.05 microm to 0.38 microm]) (P =.12)., Conclusion: The PRL showed encouraging results in treating high myopia. Additional patients and longer follow-up period are needed to detect the long-term efficacy and safety of this refractive lens.

Purpose: To evaluate the efficacy, predictability, and safety of topographically supported customized ablations (TOSCAs) for decentered ablations following laser in situ keratomileusis (LASIK)., Design: Prospective nonrandomized clinical trial., Methods: Nine patients (11 eyes) with LASIK-induced decentered ablations underwent TOSCA following flap lifting. Topographically supported customized ablation was performed using a corneal topographer to obtain a customized ablation profile, combined with a flying spot laser., Results: Mean follow-up was 9.22 +/- 2.82 months (range 6-12 months). No intra- or postoperative complications were observed. Manifest refraction (spherical equivalent) did not change significantly (pre-TOSCA: -0.14 +/- 1.58 diopters [range, -1.75 to +3.00 diopters] to +0.46 +/- 1.02 diopters [range, -1.00 to +1.75 diopters]; P =.76), whereas there was a statistically significant reduction in the refractive astigmatism (pre-TOSCA: -1.55 +/- 0.60 diopters [range, -3.00 to -0.75 diopters] to -0.70 +/- 0.56 diopters [range, -2.00 to -0.25 diopters]; P =.003). Mean uncorrected visual acuity improved significantly (P <.001) from 0.45 +/- 0.16 (range, 0.2-0.7) to 0.76 +/- 0.29 (range, 0.2-1.2) at last follow-up. Mean best-corrected visual acuity improved from 0.74 +/- 0.22 (range, 0.4-1.0) to 0.95 +/- 0.20 (range, 0.6-1.2; P =.002). Eccentricity showed a statistically significant reduction after TOSCA treatment (pre-TOSCA: 1.59 +/- 0.46 mm [range, 0.88-2.23 mm]; post-TOSCA: 0.29 +/- 0.09 mm [range, 0.18-0.44 mm]; P <.001)., Conclusion: In our small sample, enhancement LASIK procedures with TOSCA appear to improve uncorrected and best-corrected visual acuity as well as eccentricity in patients with LASIK-induced decentered ablation.

Purpose: To assess the safety, efficacy, and stability of conductive keratoplasty in the treatment of low to moderate hyperopia and evaluate the impact of the procedure on the quality of vision., Methods: Thirty-six eyes (25 patients; 13 female and 12 male) were treated for hyperopia up to +3.25 D with a Refractec ViewPoint CK system and followed for 1 year. Mean age was 50.2 +/- 8.7 years (range 31 to 71)., Results: Before surgery, mean spherical equivalent refraction was +1.90 +/- 0.60 D (range +1.00 to +3.25 D), decreasing at 1 year after conductive keratoplasty to -0.06 +/- 0.80 D, and was within +/- 0.50 D of emmetropia in 68% (24 eyes) and within +/- 2.00 D in all eyes. Twelve months after conductive keratoplasty, uncorrected visual acuity was 20/20 or better in 19 eyes (50%) and 20/40 or better in 32 eyes (89%). No eye lost > or = 2 Snellen lines or had induced cylinder > or = 2.00 D. The mean root mean square values for higher order optical aberrations were 0.060 +/- 0.039 before and 0.174 +/- 0.170 at 3 months after surgery. No statistically significant changes in contrast sensitivity were noted., Conclusions: Conductive keratoplasty for low to moderate hyperopia provided safe, effective, and stable results both in refraction and quality of vision.

Purpose: To determine how refractive error, visual acuity, and high-order aberrations (3rd- and 4th-order) are affected by the formation of a lamellar corneal flap during laser in situ keratomileusis (LASIK)., Setting: University refractive surgery center., Methods: The effect of lamellar corneal flap formation was analyzed in 15 myopic eyes (mean preoperative refraction -4.72 diopters [D] [range -1.25 to -7.25 D]). The flap was created using a 2-step procedure: (1). a nasally hinged lamellar corneal flap was created; (2). the flap was lifted and stromal ablation performed 2 months after the flap was made. A Hartmann-Shack aberrometer was used to measure the aberrations., Results: There was no significant change in the refractive error (spherical equivalent pre-flap -4.72 +/- 1.99 D and post-flap -4.62 +/- 1.99 D [P =.28]) or visual acuity (pre-flap uncorrected visual acuity [UCVA] 0.07 and best corrected visual acuity [BCVA] 0.96; post-flap UCVA 0.08 and BCVA 0.95 [P =.16 and P =.33, respectively]). A statistically significant increase in total higher-order wavefront aberrations was observed following flap formation (root mean square pre-flap 0.344 +/- 0.125 and post-flap 0.440 +/- 0.221 [P =.04])., Conclusion: Flap formation during LASIK can modify the eye's existing natural higher-order aberrations (especially spherical and coma-like aberrations along the axis of the flap's hinge), while visual acuity and refractive error remain unaffected.

Objective: To identify the incidence and refractive outcome of intraoperative laser in situ keratomileusis (LASIK) complications using one type of microkeratome., Design: Retrospective noncomparative case series., Participants: Three hundred thirty-four consecutive myopic LASIK patients (September 1997 to November 1998) operated on by one surgeon., Intervention: Myopic LASIK surgeries were performed with the Mediate Mel 60 Aesculap Meditec Laser system., Main Outcome Measures: Preoperative and 1-year postoperative spherical equivalent, best spectacle-corrected visual acuity (BSVA), and corneal anatomic features (as obtained from videokeratography) were recorded, as was the incidence of intraoperative complications., Results: Forty-eight (14%) eyes had keratome-related complications. Thirty-seven (77%) eyes were immediately treated; the remaining eyes were treated on a later date. One year after treatment, 13% of the immediately treated complicated eyes maintained the preoperative BSVA; 24% had a 1-line loss; 2.7% had a greater loss of BSVA., Conclusions: Microkeratome-related complications may result in loss of BSVA. The complication of an irregular flap had the poorest refractive outcome in this series of eyes. We did not find any statistically significant relationship between corneal anatomic factors and keratome-related complications in this series.

Purpose: The measurement of the refractive error profile is more useful than corneal topography in understanding the complexities of refractive surgery. We report on experimental studies of the spatially resolved refractometer Tracey-1, developed in Ukraine by IBME in medical cooperation with VEIC, Greece., Methods: Ten eyes were subjected to dynamic measurement of accommodation, in order to test the effectiveness of Tracey refractometry. Measurements were performed in zones 0 to 6 mm. The refractive aberrations were calculated and accommodation was evaluated., Results: Evaluation of data shows that the instrument can effectively follow the dynamic change of refractive aberrations through the accommodation process., Conclusion: Clinical tests of Tracey technology demonstrated the ability to investigate accommodation using this instrument.

Purpose: WASCA (Wavefront Aberration Supported Cornea Ablation) is a method for wavefront-guided ablation. This new method records all existing eye aberrations with the Asclepion Wavefront Aberrometer and calculates the customized pattern for laser correction. We measured the low and high order aberrations of eyes before and after PRK and LASIK, as well as before and after flap creation., Methods: The Asclepion Shack-Hartmann aberrometer was used to measure wavefront aberrations. Preoperative and postoperative measurements were made following both PRK and LASIK performed with conventional software, modified Aberration-free Profile (AFA) software, and specially designed WASCA software. Surgery was performed with the Meditec MEL-70 G-scan excimer laser. Additionally, measurements were made before and after flap creation only (10 eyes)., Results: There was a significant difference between preoperative and 1-month postoperative high order aberrations, with notable increases following conventional PRK and LASIK and less increase following modified AFA PRK and LASIK. Flap creation only changed the higher order aberrations slightly, and caused a shift toward hyperopia. In the eyes that received WASCA correction with PRK or LASIK, at 3 months postoperative the high order aberrations averaged an increase of 1.3 times for PRK and 1.8 times for LASIK. Both the AFA and WASCA treatments demonstrated improved outcomes in comparison to conventional PRK and LASIK., Conclusion: Wavefront mapping of the eye and wavefront-guided ablation with the Asclepion Aberrometer can be used for optimizing the results and fine-tuning visual performance after laser vision correction. WASCA PRK appeared to result in better outcomes than WASCA LASIK.

Purpose: In refractive surgery, measuring the total ocular profile of refraction gives more vital information than measuring the cornea alone. We report the first clinical experiments with spatially resolved refractometry using ray tracking principles. Tracey technology was developed in Ukraine by the Institute of Biomedical Engineering in cooperation with the Vardinoyannion Eye Institute of Crete., Methods: The Tracey-1 device was evaluated in comparison with conventional videokeratoscopes. Seven pseudophakic eyes of 7 patients and two phakic eyes were measured thirty (30) consecutive times (consecutively) each to test reproducibility. Measurements were provided in zones 0 to 5 (6) mm. For each zone, parameters of astigmatism were calculated and mean value and standard deviation were derived., Results: Standard deviation on the order of 0.14 D was derived., Conclusion: The Tracey Technology wavefront device provides information on the refraction distribution at the first principal plane of the ocular optical system. For the instrument to provide measurements that are directly applicable to clinical practice, the data should be transposed to the corneal plane. The Tracey device can be utilized for the measurement of accommodative amplitude and range. Further development of the instrument is requred to increase its accuracy.

Purpose: Of all transforms of an eye, aberrations are significant when higher visual acuity is to be achieved. Ray tracing aberrometry developed by the Institute of Biomedical Engineering (Kiev) and first tested at the Vardinoyannion Eye Institute of Crete is a promising technique for eye refraction aberration and refraction mapping., Methods: The technique uses measurement of the position of a thin laser beam projected onto the retina. The beam is directed into the eye parallel to the visual axis. Each entrance point provides its own projection on the retina. A set of entrance points forms a set of projections. From these data, a refraction map is reconstructed as well as a point spread function of the eye. The total time of scanning over the whole aperture of the eye is within 10 to 20 ms and depends on the number of test points at the eye entrance, as well as on the number of independent measurements in each point. Configuration of the scanning pattern can be chosen by the operator. It may contain 60 to 400 points, each checked 1 to 5 times., Results: Preliminary studies showed high reproducibility of results. Twenty pseudophakic eyes were subjected to 30 consecutive measurements each. Ninety-five percent of all measured values were within +/-0.20 D of declination from the mean., Conclusions: Ray tracing aberrometry is a flexible technology for eye investigation. It can be adapted to any laser technique of vision correction Its further development should be oriented on laser-linked applications of the refraction driven refractive surgery.