Search

Purpose: To evaluate the visual, refractive, and topographic outcomes after combined transepithelial phototherapeutic keratectomy (PTK) and conventional photorefractive keratectomy (PRK) followed simultaneously by corneal crosslinking (CXL) for keratoconus., Setting: Vardinoyiannion Eye Institute of Crete, Faculty of Medicine, University of Crete, Heraklion, Crete, Greece., Design: Prospective case series., Methods: Patients with progressive keratoconus had simultaneous conventional PRK followed by CXL; the corneal epithelium was removed using transepithelial PTK (Cretan protocol plus). The visual, refractive, and topographic outcomes and the endothelial cell density (ECD) were evaluated preoperatively and 1, 3, 6, and 12 months postoperatively., Results: Forty-three patients (55 eyes) were enrolled. The mean uncorrected and corrected distance visual acuities improved significantly from 0.98 ± 0.63 (SD) logarithm of minimum angle of resolution (logMAR) and 0.20 ± 0.23 logMAR preoperatively to 0.39 ± 0.35 logMAR (P < .001) and 0.08 ± 0.16 logMAR (P < .001) 12 months postoperatively, respectively. The mean spherical equivalent improved significantly from -4.67 ± 4.00 diopters (D) preoperatively to -2.24 ± 2.81 D (P < .001) at 12 months. The mean steep keratometry (K) and flat keratometry readings decreased significantly from 50.30 ± 5.00 D and 45.62 ± 3.10 D preoperatively to 46.27 ± 3.90 D (P < .001) and 43.46 ± 3.00 D (P < .001) 12 months postoperatively, respectively. No ECD alterations were observed throughout the follow-up (P > .05)., Conclusion: Combined transepithelial PTK and conventional PRK followed simultaneously by CXL was effective in corneal stabilization and vision improvement in keratoconic patients., (Copyright © 2017 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To present the long-term results of combined transepithelial phototherapeutic keratectomy (PTK) and corneal collagen crosslinking (CXL) for keratoconus., Setting: Vardinoyiannion Eye Institute of Crete, University of Crete, Heraklion, Crete, Greece., Design: Prospective case series., Methods: Patients with progressive keratoconus had combined transepithelial PTK and CXL (Cretan protocol). Visual and refractive outcomes and the endothelial cell density (ECD) were evaluated preoperatively and postoperatively., Results: Twenty patients (23 eyes) were enrolled; postoperatively 23 eyes were evaluated at 1 and 2 years, 11 at 3 years, and 7 at 4 years. The mean follow-up was 33.83 months±10.82 (SD) (range 24 to 56 months). No intraoperative or postoperative complications occurred. The mean uncorrected distance visual acuity improved significantly from 0.99±0.57 logMAR preoperatively to 0.61±0.36 logMAR at the last follow-up (P<.001) and the mean corrected distance visual acuity, from 0.27±0.24 logMAR to 0.17±0.14 logMAR (P=.018), respectively. The mean steep and mean flat keratometry readings decreased significantly from 53.39±7.14 diopters (D) and 47.17±4.87 D, respectively, preoperatively to 49.99±4.36 D (P<.001) and 45.47±2.95 D (P=.002), respectively, at the last follow-up. The mean corneal astigmatism improved significantly from -6.27±4.19 D preoperatively to -4.52±2.80 D (P<.001) at the last follow-up. No significant ECD alterations occurred (P>.05)., Conclusion: Combined transepithelial PTK and CXL was effective and safe in keratoconic patients over a long-term follow-up., Financial Disclosure: No 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.)

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 use anterior segment optical coherence tomography (AS-OCT) to compare corneal stroma demarcation line depth after corneal collagen crosslinking (CXL) with 2 treatment protocols., Setting: Vardinoyiannion Eye Institute of Crete, Faculty of Medicine, University of Crete, Heraklion, Crete, Greece., Design: Prospective comparative interventional case series., Methods: Corneal collagen crosslinking was performed in all eyes using the same ultraviolet-A (UVA) irradiation device (CCL-365). Eyes were treated for 30 minutes with 3 mW/cm(2) according to the standard Dresden protocol (Group 1) or for 10 minutes with 9 mW/cm(2) of UVA irradiation intensity (Group 2). One month postoperatively, 2 independent observers measured the corneal stroma demarcation line using AS-OCT., Results: Sixteen patients (21 eyes) were enrolled. Group 1 comprised 7 patients (9 eyes) and Group 2, 9 patients (12 eyes). The mean corneal stroma demarcation line depth was 350.78 μm ± 49.34 (SD) (range 256.5 to 410 μm) in Group 1 and 288.46 ± 42.37 μm (range 238.5 to 353.5 μm) in Group 2; the corneal stroma demarcation line was statistically significantly deeper in Group 1 than in Group 2 (P=.0058, t test for unpaired data)., Conclusion: The corneal stroma demarcation line was significantly deeper after a 30-minute CXL treatment than after a 10-minute CXL procedure with high-intensity UVA irradiation., (Copyright © 2014 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To compare the visual and refractive outcomes and the corneal structural changes in myopic patients after surface refractive treatments (ie, photorefractive keratectomy [PRK] with adjuvant mitomycin-C [MMC] and epithelial laser in situ keratomileusis [epi-LASIK])., Setting: University of Crete, Heraklion, Crete, Greece., Design: Prospective comparative case series., Methods: One eye of consecutive myopic patients was randomly assigned to PRK-MMC, and the fellow eye was treated with epi-LASIK. Visual and refractive outcomes and corneal confocal microscopy findings were evaluated. All patients were examined preoperatively and 1, 3, 6, 12, and 24 months postoperatively., Results: Twenty-six eyes (13 patients) were included. The mean follow-up was 2.47 years ± 0.35 (SD) (range 1.64 to 2.93 years). In the PRK-MMC group, the mean preoperative spherical equivalent refraction was -3.84 ± 1.59 diopters (D) (range -1.5 to -8.7 D) and -0.21 ± 0.44 D (range -0.5 to 1.0 D) at the last follow-up and in the epi-LASIK group, -3.91 ± 1.48 D (range -1.5 to -8.5 D) and -0.18 ± 0.36 (range +0.5 to -0.5 D), respectively. Qualitative analysis of the subepithelial nerve plexus, haze development, and keratocyte distribution were similar in the 2 groups. There was no statistically significant difference in endothelial cell density between the groups throughout the follow-up (P>.05)., Conclusion: Epithelial LASIK and PRK-MMC gave similar visual, refractive, and corneal structural outcomes in patients with myopia for up to 2 years postoperatively., Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned., (Copyright © 2013 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

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 report the 2-year follow-up of the initial clinical evaluation of Infinite Vision Optics multicomponent intraocular lens (IOL) implantation., Setting: Institute of Vision and Optics, University of Crete, Crete, Greece., Design: Case series., Methods: All patients had routine cataract surgery and multicomponent IOL implantation. The primary objectives of the study were to evaluate the manufacturing feasibility of the IOL, the evaluation of the surgical implantation technique, and the incidence of interlenticular fibrosis., Results: This initial clinical evaluation comprised 6 patients with a mean age of 63.3 years ± 12.7 (SD) (range 49 to 82 years). Implantations were uneventful in all cases. There were no intraoperative or postoperative complications. There was no interlenticular fibrosis. There was no statistically significant difference in the endothelial cell density, anterior chamber depth, or pachymetry readings between preoperatively and 2 years postoperatively. No patient lost lines of corrected distance visual acuity., Conclusions: Multicomponent IOL implantation was easy and safe and resulted in excellent visual recovery. No cases of interlenticular fibrosis developed., (Copyright © 2013 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate blue-light attenuation in eyes with a tinted intraocular lens (IOL) or an untinted IOL., Setting: Department of Ophthalmology, University Hospital of Crete, Crete, Greece., Design: Comparative case series., Methods: Patients had lens extraction and implantation of an Acrysof Natural tinted or Tecnis ZA9003 or Softec III untinted acrylic IOL. The luminance ratio of green (530 nm) and blue (465 nm) light (green:blue ratio) required for isoluminant perception was determined by heterochromatic flicker photometry. Patients were tested preoperatively and 20 days postoperatively. The parafoveal measure of the green:blue ratio, expressed in decibels, is proportional to the blue-light attenuation by the lens., Results: Twenty-two patients received the tinted IOL and 21 the untinted IOL. Preoperatively, age was strongly linearly correlated with the green:blue ratio (r = 0.59, P < .001). The mean postoperative decrease in the green:blue ratio was greater in the untinted IOL group (P = .003). Postoperatively, the tinted IOL group had a significantly higher green:blue ratio than the untinted IOL group (P < .001). In the tinted IOL group, the green:blue ratio was linearly related to IOL dioptric power., Conclusion: Less blue light reached the retina with tinted IOLs than with untinted IOLs. The absorption properties of tinted IOLs seemed to resemble those of the aging human crystalline lens, while untinted IOLs resembled the lower levels of blue-light attenuation of younger lenses. Thus, tinted IOLs may protect against the presumed blue-light hazard., Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned., (Copyright © 2011 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To determine the possible effect of corneal collagen crosslinking (CXL) with riboflavin and ultraviolet A (UVA) on intraocular pressure (IOP) measurements by Goldmann applanation tonometry (GAT)., Setting: Institute of Vision and Optics, Faculty of Medicine, University of Crete, Heraklion, Crete, Greece., Design: Prospective case series., Methods: This noncomparative study measured IOP by GAT before CXL and 6 months and 12 months after CXL., Results: The study evaluated 55 eyes (55 patients). There was a statistically significant increase in the measured IOP 6 months and 12 months after CXL (both P<.001). The mean measured IOP was 9.95 mm Hg ± 3.01 (SD) before CXL, 11.40 ± 2.89 mm Hg at 6 months, and 11.35 ± 3.38 mm Hg at 12 months. The change in IOP measurements at both postoperative examinations was not correlated with patient age, preoperative pachymetry, or preoperative keratometry readings., Conclusion: After riboflavin-UVA CXL in eyes with keratoconus, there was a significant increase in IOP measured by GAT that was probably caused by an increase in corneal rigidity., (Copyright © 2010 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To compare the efficacy of 2 types of silicone hydrogel bandage contact lenses with high oxygen transmissibility after photorefractive keratectomy (PRK)., Setting: Institute of Vision and Optics, Faculty of Medicine, University of Crete, Heraklion, Crete, Greece., Methods: In this prospective study, 1 eye of patients having bilateral PRK was randomly fitted with a bandage contact lens of lotrafilcon A (Night & Day) and the fellow eye, with a bandage contact lens of lotrafilcon B (O(2)Optix). The patients and the examiner were masked to which bandage contact lens type was in which eye. Patients were examined on the day of surgery and 1, 3, and 5 days postoperatively. Postoperative examinations included uncorrected distance visual acuity and slitlamp biomicroscopy to assess epithelial defect size. Subjective evaluation of pain and vision was recorded 1, 2, 3, and 4 days postoperatively., Results: The study enrolled 44 patients (88 eyes). The mean epithelial defect size immediately after surgery was 47.0 mm(2) with both types of bandage contact lenses. There was no statistically significant difference in epithelial defect size between the 2 lenses at any postoperative visit. Three days postoperatively, reepithelialization was complete in 75.0% of eyes in the lotrafilcon A group and 72.7% of the eyes in the lotrafilcon B group., Conclusion: There were no differences in corneal reepithelialization or subjective measurements after PRK between the 2 types of silicone hydrogel bandage contact lenses.

A 34-year-old woman had simultaneous photorefractive keratectomy and corneal collagen crosslinking with riboflavin-ultraviolet-A irradiation for the treatment of progressive pellucid marginal corneal degeneration in both eyes. No intraoperative or early postoperative complications occurred. Twelve months postoperatively, the uncorrected visual acuity was assessed at 20/40 in both eyes compared with counting fingers preoperatively. The corrected visual acuity also improved from 20/50 and 20/63 to 20/25 and 20/32 in the right eye and left eye, respectively. Corneal topography revealed a significant improvement in both eyes. Despite the encouraging results, longer follow-up is necessary to confirm the stability of the results.

Purpose: To compare the refractive outcomes after photorefractive keratectomy (PRK) for low to moderate myopic corrections using 2 excimer lasers with different repetition rates (200 Hz and 400 Hz)., Setting: University refractive surgery center., Methods: This retrospective study included all consecutive patients who underwent PRK using the 200 Hz or the 400 Hz Allegretto laser platform (WaveLight Laser Technologie AG). Thirty-five patients (70 eyes) and 29 patients (58 eyes) had PRK with the 200 Hz platform and the 400 Hz platform, respectively, using the same surgical technique., Results: The mean follow-up was 13.22 months +/- 1.16 (SD) (range 11 to 15 months). No intraoperative or early postoperative (eg, late reepithelialization) complications were found in either group. At 1 year, 66 eyes (94.2%) in the 200 Hz group and 56 eyes (96.6%) in the 400 Hz group were within +/-1.00 diopter of the attempted correction. At 3 months, 20 eyes (29%) in the 200 Hz group and 27 eyes (46%) in the 400 Hz group had mild or moderate corneal haze (P = .03). These corneas showed progressive clearing over subsequent months without statistically significant differences in haze formation between the 2 groups. Twelve months after PRK, all corneas in both groups were clear., Conclusion: Photorefractive keratectomy for the treatment of low to moderate refractive errors using a 200 Hz or 400 Hz excimer laser gave comparable results.

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 study the long-term results of photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) in low to moderate myopic corrections using the Pulzar Z1 system (CustomVis), a 213 nm wavelength solid-state laser., Setting: University refractive surgery center., Methods: This prospective noncomparative case series comprised 20 patients (40 eyes) who had refractive surgery using the Pulzar Z1 laser system. Manifest refraction, uncorrected visual acuity, best spectacle-corrected visual acuity (BSCVA), safety, predictability, stability, and confocal microscopy images were evaluated., Results: Ten patients (20 eyes) had PRK and 10 patients (20 eyes) had LASIK. The mean follow-up was 13.9 months +/- 1.1 (SD) (range 12 to 17 months) and 14.6 +/- 1.2 months (range 12 to 18 months) in the PRK group and LASIK group, respectively. No eye lost a line of Snellen BSCVA during the follow-up period; 2 eyes (10%) gained 2 Snellen lines. There was a statistically significant decrease in spherical equivalent manifest refraction postoperatively in both groups (P<.05). Refractive stability was obtained during the first postoperative month and remained stable during the follow-up period, with no significant changes between any interval in both groups (P>.05). At the last follow-up, 95% of all eyes were within +/-1.00 diopter of emmetropia. No late postoperative complications were observed., Conclusion: Refractive surgery using the Pulzar Z1 213 nm wavelength solid-state laser was a safe, effective procedure in the treatment of low to moderate myopia.

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 study the long-term efficacy, safety, and stability of laser in situ keratomileusis (LASIK) after unintentional ultrathin flap creation less than 80 mum., Setting: University refractive surgery center., Methods: This retrospective case series comprised 25 patients (33 eyes) who had LASIK after flap creation less than 80 mum with the Moria M2 disposable microkeratome (head 90 microm). Flap thickness was measured with intraoperative ultrasound pachymetry. Manifest refraction, uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity, predictability, stability, complications, patient satisfaction, and confocal microscopy images were studied., Results: The mean follow-up was 14.58 months +/- 3.73 (SD) (range 12 to 25 months). The mean flap thickness was 72.1 +/- 5.9 microm (range 58 to 80 microm), and the mean preoperative spherical equivalent (SE) refraction was -5.59 +/- 2.01 diopters (D) (range -10.25 to -3.25 D). On the first postoperative day, the UCVA was 20/25 or better. The SE manifest refraction was 1.00 D or less in all patients. The mean SE manifest refraction was -0.75 +/- 0.55 D (range -1.00 to +0.75 D) (P < .01). At the last follow-up, changes in visual acuity and manifest refraction were not statistically significant; no late postoperative complications were observed. All patients were satisfied with the final outcome. Qualitative analysis of confocal microscopy images revealed interface particles and activated keratocytes., Conclusions: Despite the small sample and retrospective nature of the study, superficial LASIK seemed to be a safe and predictable technique for myopic refractive corrections. Patients were satisfied with the results and had rapid visual recovery with no intraoperative or early or late postoperative complications. If the safety and efficacy of an ultrathin flap are confirmed by additional studies, superficial LASIK could represent a new approach that combines the advantages of surface and lamellar procedures.

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.

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.

Purpose: To evaluate the clinical results of epi-LASIK, a new surface ablation surgical technique for the treatment of low myopia., Setting: Vardinoyannion Eye Institute of Crete, University of Crete, Greece., Methods: Forty-four eyes of 31 patients had epi-LASIK for the correction of low myopia. Mean preoperative spherical equivalent was 3.71 diopters (D) +/- 1.2 (SD) (range -1.75 to -7.00 D) and the mean baseline logMAR best spectacle-corrected visual acuity was -0.01 +/- 0.06 (range 0.10 to -0.10). All the epithelial separations were performed with the Centurion epikeratome (CIBA Surgical). The enrolled patients were followed daily until the epithelial healing was complete as well as at 1- and 3-month intervals. On the operative day, patients filled out a questionnaire grading visual performance and pain score of treated eyes every 2 hours for a total of 5 records., Results: The mean epithelial healing time was 4.86 +/- 0.56 days (range 3 to 5 days). The mean logMAR uncorrected visual acuity on the day of reepithelization was 0.19 +/- 0.09 (range 0.40 to 0.10). At 1 month, the mean was spherical equivalent of the treated eyes (N=44), -0.3 +/- 0.6 D (range -1.0 to 0.87 D), and at 3 months it was (N=37), -0.10 +/- 0.4 D (range -0.75 to 0.75 D); 97% of eyes had clear corneas or trace haze 3 months after treatment., Conclusions: Preliminary clinical results suggest that epi-LASIK is a safe and efficient method for the correction of low myopia. Further studies will establish this method as an alternative surface ablation procedure.

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.

A 42-year-old man had Intacs (Addition Technology Inc.) implantation for early pellucid marginal degeneration (PMD). Two Intacs segments (0.45 mm thickness) were inserted uneventfully in the fashion typically used for low myopia correction (nasal-temporal). Eleven months after the procedure, the uncorrected visual acuity was 20/200, compared with counting fingers preoperatively, while the best spectacle-corrected visual acuity improved to 20/25 from 20/50. Corneal topographic pattern also improved. Although the results are encouraging, concern still exists regarding the long-term effect of this approach for the management of patients with PMD.

A 56-year-old woman had conductive keratoplasty (CK) for residual hyperopia and astigmatism. Three years before the procedure, the patient had arcuate keratotomy, followed by laser in situ keratomileusis 2 years later for high astigmatism correction in both eyes. During CK, a corneal perforation occurred in the right eye; during the postoperative examination, an iris perforation and anterior subcapsule opacification were seen beneath the perforation site. The perforation was managed with a bandage contact lens and an antibiotic-steroid ointment; it had a negative Seidel sign by the third day. The surgery in the left eye was uneventful. Three months after the procedure, the uncorrected visual acuity was 20/32 and the best corrected visual acuity 20/20 in both eyes with a significant improvement in corneal topography. Care must be taken to prevent CK-treated spots from coinciding with areas in the corneal stroma that might have been altered by previous refractive procedures.

To compare the effect of mechanical and alcohol-assisted excision on the histological ultrastructure of epithelial disks from human corneas. Vardinoyiannion Eye Institute of Crete, University of Crete, Medical School, Crete, Greece. Ten eyes of 10 patients were deepithelialized by 1 of 2 two techniques. In 6 eyes, a customized instrument was used to mechanically separate the epithelial layer. In 4 eyes, the epithelial disks were obtained using the conventional laser-assisted subepithelial keratectomy (LASEK) technique; that is, with alcohol concentrations of 15% and 20%. All specimens were assessed by light and electron microscopy, and the histological findings of the 2 methods were compared. Transmission electron microscopy showed that when the epithelial disks were excised by mechanical separation, the lamina densa and lamina lucida were preserved and the hemidesmosomes had normal morphology along almost the entire length of the basement membrane. The basal epithelial cells of the separated epithelial disks showed minimal trauma and edema. Specimens obtained using 15% and 20% alcohol concentrations showed formation of cytoplasmic fragments of the basal epithelial cells, enlargement of the intercellular spaces, and extensive discontinuities in the basement membrane, which was excised at the level of the lamina lucida. Mechanical separation did not affect the normal cell morphology of the excised epithelial disks. Transmission electron microscopy of the specimens proved the manual technique is less invasive to epithelial integrity than LASEK using either alcohol concentration.

To prospectively compare the influence of fornix-based and limbus-based conjunctival flaps on the final outcome and complications of 2-site phacotrabeculectomy with mitomycin-C in fellow eyes of patients with bilateral open-angle glaucoma (OAG). Glaucoma Unit, Department of Ophthalmology, University of Crete, Crete, Greece.Twenty-two patients with bilateral primary OAG and 8 patients with bilateral exfoliative glaucoma had 2-site phacotrabeculectomy in both eyes. Eyes were randomly assigned to the fornix-based flap or limbus-based flap group by the use of random tables. The intraocular pressure (IOP) decreased significantly in both groups (P <.01); however, there was no statistically significant difference between the groups in the amount of IOP decrease or the number of postoperative antiglaucoma medications after a 1-year follow-up. Faster improvement in visual acuity was observed in the fornix-based group during the first week. The mean time of surgery was 3.5 minutes less in the fornix-based group. An increased incidence of fibrin exudation, pupillary membrane formation, and capsule opacification was found in eyes with exfoliative glaucoma. The early bleb leakage was 3 times more frequent in the fornix-based group. The type of conjunctival flap in a 2-site phacotrabeculectomy did not seem to influence the final outcome. The main advantage of the fornix-based conjunctival flap is the shorter surgical time and the relatively faster improvement in vision postoperatively. The main disadvantage is more frequent early bleb leakage.

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.

Purpose: To test the accuracy and reliability of the first-generation prototype of Tracey-1, a ray-tracing refractometer., Setting: Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, USA., Methods: The refractive spherical equivalent (SE) and astigmatism measured by Tracey-1, subjective manifest refraction (MR), and autorefraction (AR) (Nidek AR-3300) were compared in 58 pseudophakic eyes of 44 patients with a mean age of 69.95 years +/- 8.6 (SD). The astigmatic values obtained from Tracey-1 and computerized videokeratography were also compared. Astigmatism values were compared using power vector analysis., Results: The mean SEs measured by MR, Tracey, and AR were -0.76 diopter (D) +/- 0.96 (SD) (range 1.00 to -3.00 D), 0.37 +/- 0.64 D (range 1.68 to -1.49 D), and -0.44 +/- 1.13 D (range 1.63 to -3.50 D), respectively. The Pearson correlation coefficients between MR and Tracey values and between MR and AR values were high (r = 0.895 and r = 0.875, respectively; both P < .0001). However, the mean difference between the Tracey and MR values was 1.13 +/- 0.48 D (range 2.45 to -0.06 D) (P < .001). The mean cylindrical differences between MR and Tracey and between MR and AR were 0.03 +/- 0.51 D (range 1.22 to -1.07 D) (P = .709) and -0.30 +/- 0.62 D (range 0.50 to -2.25 D) (P = .003), respectively. Power vector analysis revealed difference vectors of -0.16 x 60 between Tracey and MR and -0.22 x 87 between AR and MR., Conclusions: Spherical and cylindrical refractive data obtained with the Tracey system correlated well with those derived from MR; however, there was a mean spherical error of approximately 1.10 D. Further work is required to refine the accuracy and range of this device.