Lines Of Corrected Distance Visual Acuity Research Articles

Refractive outcomes of Descemet membrane endothelial keratoplasty triple procedures (combined with cataract surgery)

To describe the refractive outcomes of triple Descemet membrane endothelial keratoplasty (DMEK). Retrospective case series. The study included patients with Fuchs endothelial dystrophy and cataract without coincident pathology. Outcomes of 108 sequential triple DMEK procedures were evaluated. With a mean follow-up of 11.9 months, the median corrected distance visual acuity (CDVA) was 20/20 (range 20/15 to 20/40) and the median uncorrected distance visual acuity in eyes with a distance target (n = 84) was 20/40 (range 20/20 to 20/200). Forty-five percent of patients gained 3 or more lines of CDVA. The median refractive error was +0.43 diopter (D) (interquartile range, -0.34 to +1.17 D). Aspheric intraocular lenses (IOLs) (n = 91) did not significantly change refractive astigmatism (mean: preoperative +0.926 D ± 0.144 [SD]; postoperative +0.945 ± 0.129 D) (P = .83), while toric IOLs (n = 9) did (mean: preoperative +2.47 ± 0.36 D; postoperative +0.94 ± 0.90 D) (P = .0015). The anterior curvature measured by Scheimpflug imaging (Pentacam) did not significantly change (mean -0.06 ± 0.47) (P = .41); however, keratometry by partial coherence interferometry (IOLMaster) did (mean -0.6 ± 0.9 D) (P < .0001). Triple DMEK safely achieved excellent CDVA. Selection of the optimum IOL power is complicated by several factors. Because Fuchs dystrophy induces changes predominately in the central cornea, measurements averaging curvature over a larger area might underreport significant refractive deviations. In the absence of an algorithm to more precisely individualize IOL calculations, a refractive target of -0.75 to -1.00 D will help reduce the proportion of eyes left hyperopic. No author has a financial or proprietary interest in any material or method mentioned.

Presbyopic LASIK Using Hybrid Bi-Aspheric Micro-Monovision Ablation Profile for Presbyopic Corneal Treatments

To evaluate distance and near image quality after hybrid bi-aspheric multifocal central presbyLASIK treatments. Consecutive case series. Sixty-four eyes of 32 patients consecutively treated with central presbyLASIK were assessed. The mean age of the patients was 51 ± 3 years with a mean spherical equivalent refraction of-1.08 ± 2.62 diopters (D) and mean astigmatism of 0.52 ± 0.42 D. Monocular corrected distance visual acuity (CDVA), corrected near visual acuity (CNVA), and distance corrected near visual acuity (DCNVA) of nondominant eyes; binocular uncorrected distance visual acuity (UDVA); uncorrected intermediate visual acuity (UIVA); distance corrected intermediate visual acuity (DCIVA); and uncorrected near visual acuity (UNVA) were assessed pre- and postoperatively. Subjective quality of vision and near vision was assessed using the 10-item Rasch-scaled Quality of Vision and Near Activity Visual Questionnaire, respectively. At 1 year postoperatively, 93% of patients achieved 20/20 or better binocular UDVA; 90% and 97% of patients had J2 or better UNVA and UIVA, respectively; 7% lost 2 Snellen lines of CDVA; Strehl ratio reduced by ∼-4% ± 14%. Defocus curves revealed a loss of half a Snellen line at best focus, with no change for intermediate vergence (-1.25 D) and a mean gain of 2 lines for near vergence (-3 D). Presbyopic treatment using a hybrid bi-aspheric micro-monovision ablation profile is safe and efficacious. The postoperative outcomes indicate improvements in binocular vision at far, intermediate, and near distances with improved contrast sensitivity. A 19% retreatment rate should be considered to increase satisfaction levels, besides a 3% reversal rate.

Outcomes for Myopic LASIK With the MEL 90 excimer laser.

To evaluate the visual outcomes of myopic LASIK performed with the MEL 90 excimer laser (Carl Zeiss Meditec AG, Jena, Germany) using the Triple-A profile with a 500-Hz pulse rate. Retrospective analysis of the first 286 myopic LASIK procedures (147 patients) by two experienced surgeons in which the VisuMax femtosecond laser and MEL 90 excimer laser (Carl Zeiss Meditec) were used following a standardized surgical technique. Inclusion criteria were preoperative spherical equivalent refraction (SEQ) up to -10.38 diopters (D), cylinder up to 5.00 D, and corrected distance visual acuity (CDVA) of 20/25 or better. No nomogram adjustments were made. Patients were observed for 3 months. Flap thickness was between 80 and 110 µm and optical zone was between 6 and 7 mm. Standard outcomes analysis was performed. Preoperatively, mean SEQ was -3.83 ± 1.83 D (range: -0.13 to -10.38 D) and mean cylinder was -0.94 ± 0.86 D (range: 0.00 to -5.00 D). Mean age was 36.4 years (range: 18.2 to 74.1 years) with 50% female patients. Of this population, 138 eyes were treated by one surgeon and 148 eyes by another. The mean predictability of SEQ was -0.13 ± 0.34 D (range: -1.00 to +1.00 D). Postoperative SEQ was ± 0.50 D in 88% and ± 1.00 D in 100% of eyes. Preoperative CDVA was 20/20 or better in 97% of eyes. Postoperative uncorrected distance visual acuity was 20/20 or better in 92% and 20/25 or better in 99% of eyes. One line of CDVA was lost in 6% of eyes and no eyes lost two or more lines. There was statistically significant improvement in mesopic contrast sensitivity (CSV-1000) at 3 (P = .021), 6, 12, and 18 (all P ≤.001) cycles per degree. The MEL 90 excimer laser using the Triple-A ablation profile with a 500-Hz pulse rate was found to achieve a small but real increase in contrast sensitivity and high efficacy for myopia up to -10.00 D and cylinder up to 5.00 D without the need for a nomogram adjustment.

Visual acuity improvement in adult amblyopic eyes with an iris-fixated phakic intraocular lens: Long-term results

To evaluate the effect of implantation of iris-fixated phakic intraocular lenses (pIOLs) (Artisan) in adult amblyopic eyes. Optical Express, London, United Kingdom. Retrospective case series. The study analyzed data from 5 years of follow-up of amblyopic eyes that were implanted with iris-fixated pIOLs and had a preoperative corrected distance visual acuity (CDVA) of 6/15 or worse. Visual acuity, refraction, endothelial cell count, and complications were assessed. Data for 103 eyes were analyzed as 2 groups. Group 1 comprised 82 eyes with myopia or myopic astigmatism, and Group 2 contained 21 eyes with hyperopia or hyperopic astigmatism. The mean preoperative sphere in Group 1 was -13.42 diopters (D) ± 5.62 (SD) with a mean cylinder of -2.35 ± 1.75 D. In Group 2, the mean sphere and cylinder were +6.77 ± 1.91 D and -2.63 ± 2.43 D, respectively. The mean CDVA improved from 0.51 ± 0.15 logMAR to 0.34 ± 0.16 logMAR (P<.001) in Group 1 and from 0.54 ± 0.17 logMAR to 0.46 ± 0.14 logMAR in Group 2 (P<.005). The safety index was 1.48 in Group 1 and 1.19 in Group 2. The efficacy index was 1.21 in Group 1 and 1.00 in Group 2. The mean gain in CDVA was statistically significantly greater in Group 1 (0.17 ± 0.14 logMAR) than in Group 2 (0.08 ± 0.11 logMAR). Two or more lines of CDVA were gained by 48.8% of eyes in Group 1 and by 19.0% of eyes in Group2. The iris-fixated pIOL was a safe and effective option for improving visual acuity in adult amblyopic eyes. Dr. Schallhorn is a consultant to Abbott Medical Optics, Inc. No other author has a financial or proprietary interest in any material or method mentioned.

Presbyopic correction on the cornea

PurposeThe aim of this systematic review was to synthesize and appraise the evidence of the benefits of presbyopic correction on the cornea for visual function.SummaryComprehensive search was conducted in MEDLINE using keywords like “presbylasik”, “presbyopic refractive surgery”, “corneal pseudoaccommodation” and “corneal multifocality”. We reviewed corrected and uncorrected visual acuities for distance and near (uncorrected distance visual acuity (UDVA), uncorrected near visual acuity (UNVA), corrected distance visual acuity (CDVA), distance corrected near visual acuity (DCNVA), corrected near visual acuity (CNVA)), along with the refractive outcomes in spherical equivalent (SE) and astigmatism comparing the differences observed between preoperative myopic and hyperopic patients, as well as among techniques.Thirty-one studies met the inclusion and quality criteria. Monovision provides excellent distance and near uncorrected acuities, but with a 17% retreatment and a 5% reversal rate. Initial multifocal ablations result in 12% loss of 2 or more lines of CDVA, and a 21% retreatment rate. Laser Blended Vision provides excellent UDVA, but with a 19% retreatment rate. Initial experiences with Supracor show moderate predictability and a 22% retreatment rate. Intracor results in 9% loss of 2 or more lines of CDVA. KAMRA provides excellent UDVA, with only a 1% retreatment rate, but a 6% reversal rate. Initial experiences with PresbyMAX provided excellent UNVA and DCNVA, showing excellent predictability and a 1% reversal rate.ConclusionsThe findings have implications for clinicians and policymakers in the health-care industry and emphasize the need for additional trials examining this important and widely performed clinical procedure.

Efficacy, predictability, and safety of small incision lenticule extraction: 6-months prospective cohort study.

BackgroundTo report our experience with small incision lenticule extraction ("SMILE") for myopia treatment.MethodsIn this prospective clinical study, we evaluated 447 eyes from 224 patients with myopia, with and without astigmatism. We followed the patients for 6 months after SMILE.ResultsThe mean (±standard deviation, SD) spherical equivalent was -6.75 ± 1.65 diopters (D) preoperatively and -0.21 ± 0.37 D at 6 months postoperatively. Our data showed that 97.9% of eyes were within ±1.0 D and 86.1% were within ±0.5 D of the intended correction. Furthermore, 79.8% had an uncorrected distance visual acuity (UDVA) of 0 logMAR or less (20/20 or better in the Snellen equivalent) 6 months after surgery. Additionally, 48.5% remained unchanged, 41% gained one line of corrected distance visual acuity (CDVA), 7.2% gained two lines of CDVA, 3.3% lost one line of CDVA, and 0.3% lost two or more lines of CDVA. Age was the only predictor for worsening UDVA at 6 months postoperatively in linear regression analyses (0.07 decrease logMAR per increased 10 years of age; P < 0.05). No predictor showed an association with error in spherical equivalent refraction at 6 months postoperatively.ConclusionsSMILE is an effective and safe refractive surgery. Age was the only predictor that influenced visual outcome, but its effect appeared clinically insignificant. Faster visual recovery is also expected with improved surgical technique.

Safety of high-intensity corneal collagen crosslinking

To evaluate the safety of a new high-intensity corneal collagen crosslinking (CXL) treatment protocol for keratoconus. Vardinoyiannion Eye Institute of Crete, Faculty of Medicine, University of Crete, Heraklion, Crete, Greece. Prospective interventional case series. Patients with progressive keratoconus had CXL using a new treatment protocol with 9mW/cm(2) irradiance for duration of 10 minutes. The rate of reepithelialization, endothelial cell density (ECD), corrected distance visual acuity (CDVA), and steep and flat keratometry (K) values were evaluated preoperatively and 3 months postoperatively. Nine patients (10 eyes) were enrolled. No intraoperative or early postoperative complications were observed in any patient. The ECD did not change significantly 3 months postoperatively (P=.169). The CDVA improved from 0.19 logMAR ± 0.20 (SD) preoperatively to 0.10 ± 0.16 logMAR 3 months postoperatively; however, the improvement did not attain significance (P=.141). No eye lost lines of CDVA. The mean steep K readings decreased significantly from 48.04 ± 2.57 diopters (D) preoperatively to 46.51 ± 2.81 D 3 months postoperatively (P=.047); the mean flat K readings did not change significantly postoperatively (P=.285). Corneal collagen crosslinking at 9 mW/cm(2) irradiance for 10 minutes did not cause significant changes in ECD or intraoperative or early postoperative complications. None patient lost a line of CDVA 3 months after the procedure. No author has a financial or proprietary interest in any material or method mentioned.

Femtosecond laser–assisted hyperopic laser in situ keratomileusis with tissue-saving ablation: Analysis of 800 eyes

To evaluate the results and complications of hyperopic laser in situ keratomileusis (LASIK) with a low-energy femtosecond laser and non-custom tissue-saving ablation profile. Private practice, Siena, Italy. Case series. Hyperopic eyes with a spherical equivalent (SE) between +1.0 and +6.5 diopters (D) had LASIK. The flap (nominal thickness 110 μm) was created with a Ziemer LDV Z2 femtosecond laser and the refractive ablation performed with a Technolas 217P excimer laser in tissue-saving mode. Eight hundred eyes of 413 patients were treated. The mean preoperative values were SE, +3.41 D ± 1.16 (SD); defocus equivalent, 4.20 ± 1.33; corrected distance visual acuity (CDVA), 0.07 ± 0.08 logMAR. At 9 months, the mean SE was -0.06 ± 0.26 D and the mean defocus equivalent 0.68 ± 0.62 (both P<.05). The defocus equivalent was 0.50 D or less in 594 eyes (74.3%) and 1.00 D or less in 707 eyes (88.4%). The mean CDVA was 0.07 ± 0.06 logMAR; 3 eyes (0.4%) lost 2 lines of CDVA and 58 eyes (7.3%) lost 1 line. The mean uncorrected distance visual acuity was 0.16 ± 0.13 logMAR. The safety index was 1.0 and the efficacy index, 0.8. The mean root-mean-square induced primary spherical aberration was 0.65 μm and the mean induced primary coma, 0.24 μm (both P<.05). The low incidence of femtosecond-related complications was associated with good predictability, safety, and a low retreatment rate. The mean flap was 7 μm thicker than expected. The author has no financial or proprietary interest in any material or method mentioned.

Long-term visual outcomes after Crystalens(®) HD intraocular lens implantation.

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

Sources of Medical Error in Refractive Surgery

To evaluate the causes of laser programming errors in refractive surgery and outcomes in these cases. In this multicenter, retrospective chart review, 22 eyes of 18 patients who had incorrect data entered into the refractive laser computer system at the time of treatment were evaluated. Cases were analyzed to uncover the etiology of these errors, patient follow-up treatments, and final outcomes. The results were used to identify potential methods to avoid similar errors in the future. Every patient experienced compromised uncorrected visual acuity requiring additional intervention, and 7 of 22 eyes (32%) lost corrected distance visual acuity (CDVA) of at least one line. Sixteen patients were suitable candidates for additional surgical correction to address these residual visual symptoms and six were not. Thirteen of 22 eyes (59%) received surgical follow-up treatment; nine eyes were treated with contact lenses. After follow-up treatment, six patients (27%) still had a loss of one line or more of CDVA. Three significant sources of error were identified: errors of cylinder conversion, data entry, and patient identification error. Twenty-seven percent of eyes with laser programming errors ultimately lost one or more lines of CDVA. Patients who underwent surgical revision had better outcomes than those who did not. Many of the mistakes identified were likely avoidable had preventive measures been taken, such as strict adherence to patient verification protocol or rigorous rechecking of treatment parameters.

Long-term follow-up of riboflavin/ultraviolet A (370 nm) corneal collagen cross-linking to halt the progression of keratoconus

AimsTo determine long-term efficacy of riboflavin/ultraviolet A corneal cross-linking (CXL).MethodsThirty patients (30 eyes) who had undergone CXL following epithelial removal 4–6 years previously were examined.ResultsAt 1-year mean, spherical equivalent error...

Long-Term Visual and Refractive Outcomes following Surface Ablation Techniques in a Large Population for Myopia Correction

To evaluate the visual and refractive outcome for four wavefront-guided surface ablation (WGSA) techniques (LASEK, LASEK flap-off [LASEK FO], Epi-LASIK, and Epi-LASIK flap-off [Epi-LASIK FO]) in a large myopic population. This retrospective review included 1000 myopic eyes (spherical equivalent [SE] -1.0 to -8.0 diopters [D]) treated with WGSA (VISX STAR S4 with IR) using four different epithelial management techniques. Flaps were either retained (163 Epi-LASIK, 361 LASEK) or discarded (277 Epi-LASIK FO, 199 LASEK FO). Eyes in each group were stratified to either low, mild, moderate, or high myopia based on preoperative SE. Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction spherical equivalent (MRSE), predictability, lines lost, and haze were compared at 3, 6, and 12 months. At 1 year, UDVA and CDVA of ≥20/20 and 20/15 were comparable across the four procedure groups and within each subgroup of myopia. Predictability was less than or equal to ±0.5 D of intended correction in 96% to 99% of eyes. LASEK FO and Epi-LASIK FO outperformed the EPI-LASIK in achieved MRSE, especially in the high myopia category (-0.012, 0.040, and -0.27 D, respectively, P < 0.05). No eyes lost more than one line of CDVA; and 50% to 60% of eyes in each group gained one or more lines. No significant haze was recorded in any group. There was no statistically significant difference between groups in the preoperative MRSE and efficacy indices except for LASEK FO. At 1 year, there was no statistically significant difference in visual outcomes between techniques for any degree of myopia. However, the MRSE achieved with LASEK FO and Epi-LASIK FO were closer to emmetropia.

Intracorneal Ring Segments Implantation Followed by Same-day Topography-guided PRK and Corneal Collagen CXL in Low to Moderate Keratoconus

To evaluate the safety and efficacy of intrastromal corneal ring segments (ICRS) implantation followed by same-day topography-guided photorefractive keratectomy (PRK) and ultraviolet-A/riboflavin collagen cross-linking (CXL) in patients with low to moderate keratoconus. Patients with low to moderate keratoconus and contact lens intolerance were included in the study. All patients first underwent femtosecond laser-enabled placement of ICRS (Keraring, Mediphacos) (first step). Same-day topography-guided PRK and CXL (second step) were subsequently performed in all patients after the refraction was stable (average 6 months [range: 3 to 11 months]). Thirteen eyes from 13 patients were included in the study. Based on values before the first step and 6 months after the second step, significant improvements were noted in uncorrected distance visual acuity (0.7±0.32 logMAR vs 0.08±0.08 logMAR), corrected distance visual acuity (CDVA) (0.16±0.19 logMAR vs 0.02±0.04 log-MAR), sphere (-3.65±3.08 diopters [D] vs 0.06±1.6 D), astigmatism (-3.31±1.5 D vs -0.98±0.75 D), average K (47.28±1.99 D vs 41.42±3.22 D), and coma (2.36±1.23 μm vs 1.47±0.68 μm) (P<.05). Approximately 63% of eyes gained ⩾2 lines of CDVA, whereas no change in CDVA was reported in ∼27% of eyes. No eyes lost lines of CDVA. The combination of ICRS implantation followed by sequential same-day topography-guided PRK/CXL may be a reasonable option for improving visual acuity in patients with low to moderate keratoconus.

Outcome Analysis of Intracorneal Ring Segments for the Treatment of Keratoconus Based on Visual, Refractive, and Aberrometric Impairment

To analyze the outcomes of intracorneal ring segment (ICRS) implantation for the treatment of keratoconus based on preoperative visual impairment. Multicenter, retrospective, nonrandomized study. A total of 611 eyes of 361 keratoconic patients were evaluated. Subjects were classified according to their preoperative corrected distance visual acuity (CDVA) into 5 different groups: grade I, CDVA of 0.90 or better; grade II, CDVA equal to or better than 0.60 and worse than 0.90; grade III, CDVA equal to or better than 0.40 and worse than 0.60; grade IV, CDVA equal to or better than 0.20 and worse than 0.40; and grade plus, CDVA worse than 0.20. Success and failure indices were defined based on visual, refractive, corneal topographic, and aberrometric data and evaluated in each group 6 months after ICRS implantation. Significant improvement after the procedure was observed regarding uncorrected distance visual acuity in all grades (P < .05). CDVA significantly decreased in grade I (P < .01) but significantly increased in all other grades (P < .05). A total of 37.9% of patients with preoperative CDVA 0.6 or better gained 1 or more lines of CDVA, whereas 82.8% of patients with preoperative CDVA 0.4 or worse gained 1 or more lines of CDVA (P < .01). Spherical equivalent and keratometry readings showed a significant reduction in all grades (P ≤ .02). Corneal higher-order aberrations did not change after the procedure (P ≥ .05). Based on preoperative visual impairment, ICRS implantation provides significantly better results in patients with a severe form of the disease. A notable loss of CDVA lines can be expected in patients with a milder form of keratoconus.

Predictors for the Outcome of Small-incision Lenticule Extraction for Myopia

To study the influence of patient- and surgery-related parameters on the predictability, efficacy, and safety of small-incision lenticule extraction (SMILE) for treatment of myopia. This prospective, clinical quality, control study comprised 670 eyes from 335 patients with myopia up to -10.00 diopters (D) (spherical equivalent refraction) and astigmatism up to 2.00 D treated with SMILE in both eyes and followed for 3 months. Preoperative mean spherical equivalent refraction was -7.19±1.30 D. In eyes with emmetropia as the target refraction, 84% obtained uncorrected distance visual acuity ≤ 0.10 logMAR (20/25 or better Snellen equivalent) at 3 months. Mean corrected distance visual acuity (CDVA) improved from -0.03 to -0.05 logMAR (P<.01). Two or more lines of CDVA were lost in 2.4% (16 eyes). The achieved refraction was 0.25±0.44 D less than attempted after 3 months, and 80% (537 eyes) and 94% (631 eyes) were within ±0.50 and ±1.00 D of attempted correction, respectively. Multiple linear regression analyses revealed that spherical equivalent refraction undercorrection was predicted by increasing patient age (0.10 D per decade; P<.01) and steeper corneal curvature (0.04 D per D; P<.01). Safety and efficacy of the procedure were minimally affected by age, gender, and simultaneous cylinder correction. Undercorrection of 0.25 D and small effects of patient age and corneal curvature suggest that the standard nomogram for SMILE need only minor adjustments. This study suggests that safety and efficacy are not influenced to any clinically significant degree by easily discernible patient factors.

Femtosecond Laser Correction of Presbyopia (INTRACOR) in Emmetropes Using a Modified Pattern

To evaluate functional results and corneal changes after femtosecond laser correction of presbyopia (INTRACOR, Technolas Perfect Vision GmbH) in emmetropes using a modified treatment pattern over a 12-month period. Twenty eyes from 20 emmetropic patients were treated with a modified intrastromal INTRACOR pattern consisting of 5 central rings and 8 radial cuts in a prospective, nonrandomized, uncontrolled, open, single-center, clinical study. Refraction, visual acuity, endothelial cell density, corneal pachymetry, total corneal power, and stray light were evaluated preoperatively and 1 (except endothelial cell density and stray light), 3, 6, and 12 months postoperatively. Patients filled out a subjective questionnaire at 12 months postoperatively. Comparison of preoperative versus 12-month postoperative median values revealed a significant improvement in uncorrected near visual acuity (UNVA) from 0.60 (20/80) to 0.10 logMAR (20/25) (P<.0001) and a significant decrease in corrected distance visual acuity (CDVA) from -0.10 (20/16) to 0.00 logMAR (20/20), which equals a median loss of one line (P=.0005). Fifteen percent of patients lost two lines of CDVA in the treated eye. Subjective spherical equivalent refraction remained unchanged at 0.00 diopters (D) (P=.194). After INTRACOR treatment, significant corneal steepening of 1.40 D and midperipheral flattening of 0.50 D occurred (both P<.0001). Corneal pachymetry at the thinnest point and endothelial cell density did not change significantly (P=.829 and P=.058, respectively). After 12 months, the modified INTRACOR pattern improved UNVA in emmetropic patients without inducing a myopic shift or significant changes in endothelial cell density or pachymetry.

Clinical Results of Topography-based Customized Ablations in Highly Aberrated Eyes and Keratoconus/Ectasia With Cross-linking

To report results of a series of highly aberrated corneas treated with a topography-guided excimer laser ablation. Retrospective, nonrandomized, consecutive series of eyes treated with topography-guided photorefractive keratectomy (TG-PRK) with the customized topographical neutralization technique (TNT). Cases included postoperative refractive surgery decentered ablations, optical zone enlargement, asymmetrical astigmatism, postoperative radial keratotomy (RK), postoperative keratoplasty, keratoconus combined with collagen cross-linking (CXL), and postoperative LASIK ectasia combined with CXL. Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and manifest refraction were analyzed preoperatively and 6 months postoperatively. In decentered ablation cases, 94% of 37 eyes were within 1.00 diopter (D) of the attempted refractive outcome, with 76% within 0.50 D. Mean topographic, central, optical zone of uniform (monodioptric) power increased from 3.5 to 5.2 mm in 25 eyes. Thirty-one eyes treated for asymmetrical astigmatism showed improvement in cylinder from mean 1.31 to 0.52 D. Ten of 11 eyes treated for previous RK astigmatism achieved postoperative UDVA 20/40 or better. Twenty-seven eyes with postoperative keratoplasty astigmatism were treated, with 7 (25.9%) eyes gaining > or = 2 lines and 12 (44.4%) eyes gaining > or = 1 line of CDVA. Of eyes with keratoconus that were treated using TG-PRK with CXL, 42 (58%) eyes had UDVA 20/40 or better, and 66 (92%) eyes had CDVA 20/40 or better. Twelve (71%) of 17 eyes treated for postoperative LASIK ectasia using TG-PRK with CXL had UDVA 20/40 or better. Nine (53%) eyes gained > or = 2 lines of CDVA. Topography-guided laser treatment with custom TNT, combined with CXL in keratoconus and ectasia, is an effective, safe, and increasingly predictable option for highly aberrated corneas.

Indications for intrastromal corneal ring segments in ectasia after laser in situ keratomileusis

To evaluate clinical results of intrastromal corneal ring segments (ICRS) in a large series of post-laser in situ keratomileusis (LASIK) ectasia and determine which clinical parameters were related to the success of this technique. Vissum Corporation and Clínica Baviera Group, Alicante, Spain. Case series. Intrastromal corneal ring segments were implanted to correct the spherocylindrical error and improve visual acuity. Based on a previously described grading system, the best indications for ICRS implantation to treat post-LASIK ectasia were evaluated. The variables related to favorable outcomes over a 12-month follow-up were determined. Patients who lost 2 or more lines due to post-LASIK ectasia had a mean gain of +2.89 lines of corrected distance visual acuity (CDVA) after ICRS implantation (P<.001) and a mean CDVA of 0.81 (95% confidence interval, 0.74-0.88). In contrast, patients who did not lose vision after ectasia had a mean loss of -2.00 lines of CDVA after the ICRS implantation (P<.001). The odds ratio of a gain of at least 1 line of CDVA was 18 times greater for those who had lost 2 or more lines of CDVA after ectasia. The best indications for ICRS were a loss of 2 or more lines of CDVA after ectasia and post-LASIK ectasia grade 4. Patients who do not have vision loss after ectasia and those classified as grade 1 should not be considered candidates for ICRS implantation. No author has a financial or proprietary interest in any material or method mentioned.

Pilot study of hyperopic LASIK using the solid-state laser technology

To evaluate and report the visual, refractive, and aberrometric outcomes of LASIK for the correction of low to moderate hyperopia in a pilot group using a commercially available solid-state laser Prospective pilot study including 11 consecutive eyes with low to moderate hyperopia of six patients undergoing LASIK surgery using the Pulzar Z1 solid-state laser (CustomVis Laser Pty Ltd., currently CV Laser). Visual, refractive, and aberrometric changes were evaluated. Potential complications were evaluated as well. Mean follow-up time was 6.6 months (range, 3 to 11 months). A significant improvement in LogMAR uncorrected distance visual acuity (UDVA) was observed postoperatively (p = 0.01). No significant change was detected in LogMAR corrected distance visual acuity (CDVA) (p = 0.21). Postoperative LogMAR UDVA was 0.1 (about 20/25) or better in ten eyes (90.9 %). Mean overall efficacy and safety indices were 1.03 and 1.12. Postoperatively, no losses of lines of CDVA were observed. Postoperative spherical equivalent was within ± 1.00 D in ten eyes (90.9 %). With regard to aberrations, no statistically significant changes were found in higher order and primary coma RMS postoperatively (p ≥ 0.21), and only minimal but statistically significant negativization of primary spherical aberration (p = 0.02) was observed. No severe complications were observed. LASIK surgery using the solid-state laser technology seems to be a useful procedure for the correction of low to moderate hyperopia, with minimal induction of higher order aberrations.

Comparison of visual and refractive results of Toric Implantable Collamer Lens with bioptics for myopic astigmatism

To compare visual and refractive results of Toric Implantable Collamer Lens (TICL) and bioptics (ICL plus excimer corneal surgery) to treat myopic astigmatism. Eighty-one eyes underwent TICL implantation and 83 eyes were treated with bioptics (corneal ablation was performed between 1.5 and 6 months after ICL implantation). Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), refraction, adverse events, safety, and efficacy were evaluated 12 months postoperatively. At 12 months postoperatively, the mean spherical equivalent was -0.15 ± 0.36 diopters (D) in the TICL group and -0.08 ± 0.26 D in the bioptics group (p = 0.099). Sixty-six (81.5 %) and 78 (94.0 %) eyes were within ±0.50 D for TICL and bioptics groups, respectively. The mean Snellen UDVA was not statistically different between both procedures (p = 0.909); 53 (65.4 %) and 54 (65.1 %) eyes achieved at least 20/25 or better in TICL and bioptics groups, respectively. No eye had lost more than two lines of CDVA, and 32.1 % of eyes (26/81) in the TICL group and 57.8 % of eyes (48/83) in the bioptics group had better postoperative UDVA than preoperative CDVA (p < 0.001). Safety was not statistically different between groups (p = 0.464) while efficacy was significantly higher in the bioptics group (p = 0.000). Two eyes with a TICL were treated to correct TICL decentration. Bioptics showed slightly better outcomes in some clinical measures such as uncorrected visual acuity, efficacy, and refractive predictability. TICL implantation shows reliable results similar to bioptics. A single procedure with TICL implantation might be preferred, eliminating the inherent risks of laser treatments and the risks of a second surgical procedure.