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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 (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.]., (Copyright 2019, SLACK Incorporated.)

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 follow-up., 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. [J Refract Surg. 2016;32(5):318-325.]., (Copyright 2016, SLACK Incorporated.)

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 present the results after simultaneous conventional photorefractive keratectomy combined with corneal collagen cross-linking for pellucid marginal corneal degeneration., Methods: In this prospective, interventional case series, 6 patients (8 eyes) with pellucid marginal corneal degeneration were enrolled. All patients underwent simultaneous conventional photorefractive keratectomy combined with corneal collagen cross-linking; corneal epithelium was removed by transepithelial phototherapeutic keratectomy during treatment (Cretan protocol plus conventional photorefractive keratectomy). Visual and refractive outcomes were evaluated along with endothelial cell density preoperatively and at 1, 3, 6, and 12 months postoperatively., Results: No intraoperative or postoperative complications were observed in any of the patients. LogMAR mean uncorrected distance visual acuity improved significantly from 1.05 ± 0.33 preoperatively to 0.41 ± 0.27 (P = .018) at 12 months postoperatively. Mean corrected distance visual acuity did not change significantly (P > .05) postoperatively. Mean spherical equivalent improved significantly from -3.52 ± 2.29 diopters preoperatively to -1.57 ± 1.76 diopters (P = .028) at last follow-up. Mean corneal astigmatism was significantly reduced from -6.83 ± 2.33 diopters preoperatively to -4.71 ± 1.89 diopters (P = .018) at the last follow-up. No endothelial cell density alterations were observed throughout the follow-up period (P > .05)., Conclusions: Simultaneous conventional photorefractive keratectomy combined with corneal collagen cross-linking seems to be an effective, safe, and promising treatment for the management of pellucid marginal corneal degeneration., (Copyright 2014, SLACK Incorporated.)

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., (Copyright 2014, SLACK Incorporated.)

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 evaluate the outcomes of refractive surgery in patients with topographic superior corneal steepening., Methods: This retrospective, noncomparative, interventional, clinical study included 16 patients (29 eyes) with persistent superior corneal steepening as a variation of corneal curvature (inferior to superior topographic corneal difference of at least 1.00 diopter [D] at a 3-mm zone) not related to any underlying disease or condition who underwent corneal refractive surgery. Refractive, keratometric, and visual outcomes were evaluated preoperatively and at 1, 3, 6, 12, and 24 months postoperatively., Results: Twenty-two eyes underwent photorefractive keratectomy and 7 eyes underwent LASIK. Mean follow-up was 27.38±2.37 months (range: 25 to 32 months). Mean preoperative inferior to superior keratometric difference was 1.61±0.36 D (range: 1.20 to 2.63 D). Mean preoperative spherical equivalent refraction was -4.45±1.66 D (range: -2.25 to -8.00 D), which decreased to -0.09±0.61 D (range: +0.75 to -1.38 D) (P<.05) at last follow-up. Mean preoperative topographic corneal astigmatism was 1.44±0.79 D (range: 0.52 to 3.83 D), which decreased to 0.66±0.39 D (P<.05) 3 months postoperatively and remained stable during follow-up (P<.54). Mean preoperative uncorrected distance visual acuity and corrected distance visual acuity in logMAR units were 1.57±0.62 and 0.02±0.06, respectively, which improved at last follow-up to 0.00±0.05 and -0.02±0.04, respectively. No intra- or postoperative complications were noted; specifically, no patients developed postoperative ectasia., Conclusions: Corneal refractive surgery in patients with isolated topographic superior corneal steepening provided acceptable refractive and visual outcomes without any intra- or postoperative complications. Diligence is required to screen for the potential of ectatic corneal disorders in this population. Photorefractive keratectomy may be a safer option for these patients than LASIK., (Copyright 2012, SLACK Incorporated.)

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 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., (Copyright 2011, 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 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 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., (Copyright 2009, SLACK Incorporated.)

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 evaluate possible changes of the ocular rigidity coefficient in vivo after photorefractive keratectomy (PRK) in a series of rabbit eyes, using an invasive ocular rigidity measurement device., Methods: Sixteen eyes of 8 rabbits were used in this study. One eye from each rabbit underwent PRK for -10.00 diopters (D) in a 5-mm optical zone (92 microm) while the fellow eye served as the control. Five weeks later, the rabbits were examined under general anesthesia. The pressure-volume relationship and the ocular rigidity coefficient were determined in all 16 eyes, by injecting 200 microL of saline solution (in increments of 4.5 microL) through the limbus into the anterior chamber, while the intraocular pressure (IOP) was continually monitored with a transducer, up to a maximum limit of 40 mmHg. Data within an IOP range of 10 to 40 mmHg were used to calculate the ocular rigidity coefficient., Results: The preoperative central corneal thickness was comparable (P = .73, paired t test) in the pre-PRK eyes (mean: 347.5 +/- 17.11 microm) and control eyes (mean: 349.1 +/- 17.46 microm). No statistically significant difference was noted in measured ocular rigidity coefficient between eyes treated with PRK and control eyes (mean rigidity coefficient: 0.42 +/- 0.12 mmHg/microL [range: 0.23 to 0.56] and 0.47 +/- 0.12 mmHg/microL [range: 0.28 to 0.62], respectively, with 95% confidence interval of the difference, lower: -0.10 to upper: 0.015, P = .121)., Conclusions: Photorefractive keratectomy did not significantly alter ocular rigidity measurements in this experimental model.

Purpose: To present 15-year follow-up of one of the first LASIK-treated patients., Methods: A 40-year-old woman underwent LASIK in the left eye for myopia in July 1991., Results: Fifteen years after LASIK, spherical equivalent error was statistically significantly reduced from preoperative -8.75 -3.75 x 025 degrees to postoperative -4.25 -2.75 x 010 degrees. Six months postoperatively, refractive and topographic stability was obtained and remained stable during follow-up with no significant changes between interval mean time (-3.75 -3.00 x 020 degrees 6 months postoperatively to -4.25 -2.75 x 010 degrees 15 years postoperatively). No early or late postoperative complications were observed, and confocal microscopy revealed a regenerated nerve plexus and normal cornea. However, increased scattering and presence of debris were observed at the flap interface even after 15 years. Despite moderate predictability (residual refractive error) and small optical zone, the patient was satisfied with final outcome., Conclusions: One of the first LASIK-treated patients was presented 15 years after surgery. LASIK in this patient had low predictability, although refractive and topographic stability occurred after the sixth postoperative month. No long-term, sight-threatening complications were identified during follow-up.

Purpose: To evaluate the accuracy and consistency of corneal flap thickness, horizontal diameter, and hinge size with the Moria M2 90-microm single use head., Methods: Fifty-two myopic patients (104 eyes), mean age 32.6 years, underwent bilateral LASIK with a superior hinged flap using the Moria M2 microkeratome (90-microm single use head). Prospective evaluation included flap thickness (subtraction method), diameter, hinge size, interface particles, intraoperative complications, and visual recovery., Results: The mean preoperative spherical equivalent refraction was -5.72 +/- 2.59 diopters (D) (range: -2.88 to -10.75 D) and -5.84 +/- 2.73 D (range: -3.13 to -9.38 D) for right and left eyes, respectively. The mean preoperative central corneal thickness was 548 +/- 24 microm and 547 +/- 25 microm for right and left eyes, respectively. The mean preoperative steepest K was 44.12 +/- 1.28 D and 44.41 +/- 1.27 D for right and left eyes, respectively. Corneal diameter (white-to-white) was 12 +/- 0.4 mm and 11.9 +/- 0.4 mm for right and left eyes, respectively. The mean postoperative flap thickness was 109 +/- 18 microm (range: 67 to 152 microm) and 103 +/- 15 microm (range: 65 to 151 microm) for right and left eyes, respectively. The mean postoperative flap diameter was 9.4 +/- 0.3 mm (expected mean according to the nomogram given by the company was 9.5 mm). The mean postoperative hinge chord was 4.4 +/- 0.4 mm (expected mean 4.2 mm). No interface particles were detected on slit-lamp examination., Conclusions: The Moria M2 90-microm single use head is safe with reasonable predictability for LASIK flap creation.

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.

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 microm., 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 microm., 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.

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.

Purpose: To evaluate the safety and efficacy of intrastromal corneal ring segments (ICRS, INTACS, Keravision) for the correction of corneal ectasia after laser in situ keratomileusis (LASIK)., Methods: In this prospective, noncomparative case series, INTACS were implanted in three eyes (two patients) that were ectatic after LASIK. Mean follow-up was 8.7 months (range, 8 to 10 mo)., Results: No intraoperative complications occurred. After INTACS implantation, uncorrected visual acuity ranged from 20/20 to 20/25 at 6 months and remained stable until 9 months. Mean postoperative spherical equivalent refraction was 0.50 D at 1 month and no significant changes appeared up to 9 months after INTACS implantation. After INTACS implantation, no eye lost any lines of Snellen spectacle-corrected visual acuity and two eyes gained from one to two lines. There was an increase in topographical regularity in all three eyes., Conclusion: Implantation of INTACS in eyes with corneal ectasia after LASIK resulted in good refractive outcome, absence of complications, and improvement in visual acuity.