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PURPOSE: To compare the long-term outcomes of corneal cross-linking (CXL) for the treatment of keratoconus using two different techniques for epithelial removal: transepithelial phototherapeutic keratectomy (t-PTK) and mechanical epithelial debridement. METHODS: In this prospective, comparative, interventional case series, 26 patients (30 eyes) with progressive keratoconus underwent CXL treatment. Fifteen eyes (13 patients) underwent epithelial removal with t-PTK (Cretan protocol) and 15 eyes (13 patients) underwent mechanical epithelial debridement (Dresden protocol) during CXL. Visual, refractive, and keratometric outcomes were evaluated preoperatively and at 1, 2, 3, and 4 years postoperatively. RESULTS: No intraoperative or postoperative complications were observed in any of the patients. In the Cretan protocol group, mean uncorrected (UDVA) and corrected (CDVA) visual acuity improved from 0.99 ± 0.42 and 0.33 ± 0.28 logMAR preoperatively to 0.75 ± 0.32 (No intraoperative or postoperative complications were observed in any of the patients. In the Cretan protocol group, mean uncorrected (UDVA) and corrected (CDVA) visual acuity improved from 0.99 ± 0.42 and 0.33 ± 0.28 logMAR preoperatively to 0.75 ± 0.32 (P =.018) and 0.21 ± 0.16 (P =.024) logMAR at 4 years postoperatively, respectively. In the Dresden protocol group, mean UDVA improved from 0.83 ± 0.47 logMAR preoperatively to 0.63 ± 0.40 logMAR (P =.033) at 4 years postoperatively, whereas mean CDVA did not demonstrate a statistically significant improvement postoperatively (P >.05). In the Cretan protocol group, mean corneal astigmatism improved from −6.19 ± 4.54 diopters (D) preoperatively to −4.68 ± 3.10 D (P =.041) at last follow-up, whereas in the Dresden protocol group there was no statistically significant difference postoperatively (P >.05). CONCLUSIONS: Epithelial removal with t-PTK during CXL (Cretan protocol) resulted in better visual, refractive, and keratometric outcomes compared with mechanical epithelial debridement over a long-term follow-up. [[J Refract Surg. 2019;35(10):650–655.] [ABSTRACT FROM AUTHOR]

PURPOSE: To compare clinical outcomes of three different techniques of combined cataract and Presbia Flexivue Microlens refractive corneal inlay (Presbia Coöperatief U.A., Amsterdam, Netherlands) implantation surgery for presbyopia compensation over a 12-month followup. METHODS: In this comparative pilot study, 15 patients with bilateral cataract were allocated to one of three groups with a different combination of surgical steps (cataract surgery, intrastromal pocket creation, and inlay implantation). In the three-step group, the intracorneal pocket was created in the non-dominant eye, bilateral cataract surgery was performed 3 months later, and the intracorneal inlay was inserted 3 months after that. In the two-step at 3 days group, bilateral cataract surgery was performed 3 days after pocket creation and inlay implantation in the non-dominant eye. In the two-step at 3 months group, the pocket creation and the inlay implantation were performed in the non-dominant eye 3 months after bilateral cataract surgery. Visual, refractive, and contrast sensitivity outcomes were evaluated and compared between the three groups. RESULTS: Twelve months after the inlay implantation, mean monocular uncorrected distance visual acuity was 20/32 in the three-step group, 20/32 in the two-step at 3 days group, and 20/25 in the two-step at 3 months group. Achieved mean monocular uncorrected near visual acuity was similar in the three groups (20/25). The visual and refractive outcomes did not show significant differences between groups. Contrast sensitivity was similar between groups under mesopic and photopic conditions. No intraoperative or postoperative complications were observed. CONCLUSIONS: Clinical outcomes of three different techniques of combined cataract surgery and refractive corneal inlay implantation had no apparent differences between them. The corneal inlay provided excellent near vision acuity, with high patient satisfaction and a high spectacle independence rate after cataract surgery. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

PURPOSE: To present the results after simultaneous conventional photorefractive keratectomy combined with corneal collagen cross-linking for pellucid marginal corneal degeneration. [ABSTRACT FROM AUTHOR]

PURPOSE: The multi-component intraocular lens (IOL) (IVO; SAS, Strasbourg, France) is a novel approach to the treatment of pediatric cataract. Because the refractive requirements for pediatric eyes often change over time, current IOL technology does not easily allow refractive adjustments after the primary surgical intervention. The multi-component IOL concept allows easy, surgical refractive adjustments to the initial surgical implantation at any postoperative time period. Thus, both surgical implantation and enhancement surgery have been successfully accomplished in adult patients. METHODS: A novel surgical approach to pediatric cataract surgery is described. At the time of the primary surgery, a two component IOL was implanted. At any postoperative time period, the front lens component, located in front of the capsular bag, could be easily surgically exchanged because the dioptric power requirements of the pediatric eye changed over time. RESULTS: Both primary and enhancement surgeries have been done in adult patients with good results. Implantations have occurred uneventfully in all cases with no intraoperative or postoperative complications. There was no statistically significant difference in the endothelial cell density, anterior chamber depth, and pachymetry readings preoperatively and 2 years postoperatively. There was no interlenticular fibrosis present. CONCLUSION: The multi-component IOL should provide a unique and greatly needed surgically adjustable approach to the treatment of pediatric cataract. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Purpose: To present the results after simultaneous photorefractive keratectomy (PRK) followed by corneal collagen cross-linking (CXL) for progressive keratoconus. Methods: Twelve patients (14 eyes) with progressive keratoconus were prospectively treated with customized topography-guided PRK with the Pulzar Z1 (wavelength 213 nm, CustomVis) immediately followed by corneal collagen CXL with the use of riboflavin and ultraviolet A irradiation. Results: Mean follow-up was 10.69±5.95 months (range: 3 to 16 months). Mean preoperative spherical equivalent refraction (SE) was −3.03±3.23 diopters (D) and defocus was 4.67±3.29 D; at last follow-up SE and defocus were statistically significantly reduced to −1.29±2.05 D and 3.04±2.53 D, respectively (P<.01). Preoperative mean (logMAR) uncorrected visual acuity was 0.99±0.81 and best spectacle-corrected visual acuity was 0.21±0.19, which improved postoperatively to 0.16±0.15 and 0.11±0.15, respectively. The mean steepest keratometry was reduced from 48.20±3.40 D preoperatively to 45.13±1.80 D at last follow-up. Conclusions: Simultaneous PRK followed by CXL seems to be a promising treatment capable of offering functional vision in patients with keratoconus. [J Refract Surg. 2009;25:S807–S811.] [ABSTRACT FROM AUTHOR]

PURPOSE: To determine whether the use of topical apraclonidine just before the LASIK procedure prevents subconjunctival hemorrhage and to study its effect on postoperative flap adherence. METHODS: Topical apraclonidine 0.125% was randomly applied to 1 eye of 66 myopic patients who underwent primary bilateral LASIK. Apraclonidine was instilled 1 hour prior to and 30 seconds before placing the vacuum ring of the microkeratome, whereas the other eye served as control. Thirty minutes after the operation, all patients were examined by the surgeon to evaluate hyperemia and identify flap-related complications (eg, slippage, dislocation, or flap folds). The size of subconjunctival hemorrhage was also evaluated on postoperative days 1 and 7. All 132 eyes in the study were examined after surgery to identify flap folds and/or their dislocation. RESULTS: In the apraclonidine group, 48 (72.8%) eyes had no hyperemia, 16 (24.2%) eyes had mild hyperemia, 2 (3%) eyes had moderate hyperemia, and no (0%) eyes had severe hyperemia. In the control group, 37 (56.1%) eyes had mild hyperemia, 21 (31.8%) eyes had moderate hyperemia, 1 (1.5%) eye had severe hyperemia, and 7 (10.6%) eyes had no hyperemia. In the apraclonidine group, 44 (66.7%) eyes had no subconjunctival hemorrhage (grade 0); grade 1 was present in 19 (28.8%) eyes whereas grades 2 and 3 were present in 2 (3%) eyes and 1 (1.5%) eye, respectively. In the control group, 19 (28.8%) eyes showed grade 0, 13 (19.7%) eyes had grade 1, and grades 2 and 3 were present in 20 (30.3%) eyes and 14 (21.2%) eyes, respectively. Chi-square test showed a highly significant difference between the two groups (P<.001). No flap-related problems were reported in either group. CONCLUSIONS: Topical apraclonidine applied before LASIK surgery may prevent immediate postoperative hyperemia and prolonged subconjunctival hemorrhage by its alpha-mimetic vasoconstrictor effect without inducing flap adherence complication. [ABSTRACT FROM AUTHOR]

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 logMAR (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 logMAR (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. [ABSTRACT FROM AUTHOR]

PURPOSE: To report the histological findings of four eyes of three patients who underwent epi-LASIK treatment for the correction of low myopia. METHODS: The epithelial sheets were harvested either immediately after separation (one eye) or were accidentally dislocated and harvested from the operative eyes 24 hours after treatment (three eyes). All sheets underwent optical and transmission electron microscopy. RESULTS: Histological evaluation showed that the majority of the epithelial cells were morphologically normal in all examined specimens. CONCLUSIONS: Histological examination of specimens in four eyes showed that 24 hours after mechanical separation the epithelial cells' morphology was close to normal. [ABSTRACT FROM AUTHOR]

PURPOSE: To determine the possible impact of conductive keratoplasty (CK) on intraocular pressure (IOP) measurements. METHODS: A prospective, single-center, noncomparative interventional case series was performed. Baseline and postoperative IOPs were measured by Goldmann applanation tonometry in 32 eyes of 18 patients who underwent CK for hyperopia correction. Mean follow-up was 11.9 months (range: 8 to 18 months). RESULTS: After CK, a statistically significant decrease in the measured IOP was observed (before CK: 14.22±1.64 vs after CK: 12.66±2.21, P<.001). The change in IOP readings postoperatively was not correlated with age, sex, keratometric readings, or attempted correction. CONCLUSIONS: Despite the limitations due to the small number of patients enrolled in this study, the applanation tonometer appears to underestimate the true IOP after CK. [ABSTRACT FROM AUTHOR]

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 ≥2 Snellen lines or had induced cylinder ≥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. [ABSTRACT FROM AUTHOR]

PURPOSE: To evaluate the efficacy of conductive keratoplasty in the treatment of pre-existing and surgically induced hyperopic astigmatism. METHODS: In this prospective, noncomparative case series, four eyes of four subjects, two female and two male (age 25 to 47 yr) were treated for hyperopia (up to +5.50 D) and hyperopic astigmatism (up to +5.75 D) with the Refractec ViewPoint conductive keratoplasty system. The follow-up period was 6 months. Uncorrected and spectacle-corrected visual acuity, manifest and cycloplegic refraction, and videokeratographs were obtained before and after surgery. We treated two patients who had already had LASIK, one of them with a decentered ablation and the other with flap striae, one patient after PRK, and one patient with keratoconus. RESULTS: No complications were observed. No eye lost lines of spectacle-corrected visual acuity. All eyes showed improvement of uncorrected visual acuity of 3 or more lines. Videokeratographs demonstrated improved centration and reduction in keratometric power readings. Each eye was analyzed separately, including a comparative analysis of the proposed nomograms and quality of vision after surgery. CONCLUSIONS: Conductive keratoplasty may be a minimally invasive solution for patients with irregular hyperopic astigmatism, offering improved quality of vision in instances of flap striae by tightening the central cornea. [ABSTRACT FROM AUTHOR]

PURPOSE: The aim of the current study was to control the hypothetical effects of decreased laser energy delivered to the peripheral cornea during phototherapeutic keratectomy (PTK) and provide quantitative calculation of induced low and high order aberrations. METHODS: We employed a model eye to simulate the refractive effect of homogeneous laser corneal irradiation, as in PTK, for different laser fluences (range 125 to 225 mJ/cm²) and treatment depths up to 200 µm. RESULTS: The hyperopic shift induced by the relatively lower energy delivered at the peripheral ablation zone during PTK was proportional to the treatment depth and inversely proportional to the energy fluence. The hyperopic shift calculated using the above ablation parameters was lower compared to previously reported clinical results. Higher order wavefront aberration (total root mean square) changes were of minimal significance for treatment depths up to 200 µm. CONCLUSIONS: After PTK, a hyperopic shift cannot be attributed to the energy delivery method alone. Modification of laser energy delivery algorithms may only minimize PTK-induced hyperopia. [ABSTRACT FROM AUTHOR]

Purpose: To describe the technique of femtosecond laser–assisted intracorneal pocket creation, using a mask for the implantation of a corneal inlay in the non-dominant eye of a 56-year-old, emmetropic, presbyopic woman for the correction of presbyopia. Methods: Using the iFlap treatment-type software of the femtosecond laser (IntraLase 150, Abbott Medical Optics), a full lamellar cut was created at 280-μm depth. A keyhole-shaped mask was placed at the internal part of the glass of the applanation cone. A separator was used to separate the stroma, and an inserter was used to implant the inlay at the center of the line of sight. To determine the line of sight, the microscope and centration system of the excimer laser (Allegretto Wave 400 Hz, WaveLight Laser Technologie AG) were used. The Flexivue Microlens inlay (Presbia) was implanted. Results: No intra- or postoperative complications occurred during follow-up. Uncorrected near visual acuity improved from 20/50 to 20/20 at the first postoperative week. Conclusions: Femtosecond-assisted intracorneal pocket creation using a mask is a simple, safe, and efficient approach for the implantation of corneal inlays. [ABSTRACT FROM AUTHOR]

PURPOSE: To report a case of laser in situ keratomileusis (LASIK) in a patient with previous conductive keratoplasty. METHODS: A 48-year-old man underwent conductive keratoplasty for low hyperopic astigmatism (manifest refraction OD: +2.25 -0.50 x 77°; OS: +2.50 -0.50 x 105°). Three months postoperatively, UCVA was 20/25 and BSCVA was 20/20 in both eyes; manifest refraction OD: -0.25 -0.75 x 110°; OS: +0.75 -0.75 x 50°. Sixteen months after the operation, regression of refractive outcome was (manifest) OD: +1.75 -1.25 x 90°; OS: +2.50 -0.50 x 85°; UCVA was 20/40 in the right eye and 20/63 in the left eye and BSCVA was 20/20 in both eyes. LASIK was performed for hyperopic regression in the left eye using an automated microkeratome (Alcon SKBM, 130-µm plate; Aesculap-Meditec MEL 70 excimer laser). RESULTS: LASIK was uneventful and no intraoperative or postoperative complications related to the previous conductive keratoplasty procedure or LASIK were observed. Three months after LASIK and 19 months after the initial conductive keratoplasty, the patient's left eye was emmetropic; UCVA was 20/20-2, BSCVA was 20/20 and manifest refraction was +0.25 -0.25 x 35°. There was a uniform increase in topographical steepening. Visual acuity, refraction and topographic findings remained unchanged at 6 months. CONCLUSIONS: Even though our experience is limited, treatment of hyperopia with LASIK in an eye with refractive regression following previous conductive keratoplasty resulted in a predicted refractive outcome, with no complications, and improvement in visual acuity at 6 months followup. [ABSTRACT FROM AUTHOR]