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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. [Copyright &y& Elsevier]

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. [Copyright &y& Elsevier]

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 μm ± 0.08 μm [range 0.09 μm to 0.38 μm]; post-PRL RMS: 0.21 μm ± 0.08 μm; [range 0.05 μm to 0.38 μm]) (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. [Copyright &y& Elsevier]

: PurposeTo compare the effect of mechanical and alcohol-assisted excision on the histological ultrastructure of epithelial disks from human corneas.: SettingVardinoyiannion Eye Institute of Crete, University of Crete, Medical School, Crete, Greece.: MethodsTen 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.: ResultsTransmission 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.: ConclusionsMechanical 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. [Copyright &y& Elsevier]

: PurposeTo 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).: SettingUniversity refractive surgery center.: MethodsThe 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.: ResultsThere 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]).: ConclusionFlap 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. [Copyright &y& Elsevier]