Search

Purpose: To investigate patterns of short- and long-term variations in corneal epithelial thickness (CET) after myopic laser in situ keratomileusis (LASIK) using anterior segment optical coherence tomography (AS-OCT) combined with Placido disk-based topography. Methods: In this retrospective study, 36 subjects (72 eyes) who underwent LASIK myopic surgery and 53 healthy subjects (106 eyes) who served as controls were enrolled. AS-OCT (MS-39) was performed in all patients before, 1 day, 1 month, and 6 months after surgery. Statistical analysis was performed to analyze CET changes over time after LASIK and to detect patterns of definitive CET remodeling compared to healthy subjects. Multivariate analysis was performed to look for possible predictors of final CET. Results: There was no statistically significant difference between groups in terms of demographic and anterior segment parameters (all P > 0.05). After LASIK, all sectors and rings got thicker over time (1.62–8.32 μm; P < 0.01). Except for the central sector, all areas achieved the thickest CET value one day after surgery with a progressive epithelial thinning between 1 and 6 months of follow-up. Changes on CET occurred independently of the grade of myopia before LASIK or final refraction (P > 0.05). None of the clinical variables studied, including diopters corrected, were found to be correlated with final CET (P > 0.05). Conclusion: Independent of anterior segment parameters and diopters corrected, CET becomes thicker after LASIK surgery. Central and inner ring sectors thicken more than those more peripheral. CET remodeling after myopic LASIK should be taken into consideration when planning refractive surgery.

PURPOSE: To evaluate factors associated with the change in dry eye symptoms following laser vision correction. METHODS: This was a retrospective case series of 13,319 patients who underwent laser in situ keratomileusis (LASIK) or photorefractive keratectomy (PRK) between January 2013 and February 2016 and completed a preoperative and 3-month postoperative patient-reported outcome questionnaire. RESULTS: In a multivariate linear regression model, women and contact lens wearers were associated with worse preoperative dry eye symptoms. Age was not significantly associated with preoperative dry eye symptoms. The change in dry eye symptoms preoperatively to postoperatively was affected by gender, procedure type, and preoperative dry eye symptoms. Patients who underwent PRK were more likely to report an increase in dry eye after 3 months (coefficient: 3.99, 95% confidence interval (CI): 1.64 to 4.82, P < .001) and patients with worse preoperative dry eye were more likely to have improvement in symptoms after surgery (coefficient: −0.93, 95% CI: −0.97 to −0.90, P < .001). More women reported an increased level of symptoms 3 months after surgery than men (coefficient: 1.76, 95% CI: 0.68 to 2.84, P = .001). CONCLUSIONS: Preoperative dry eye symptoms, female gender, and procedure type had a significant effect on preoperative to postoperative change in dry eye symptoms after laser vision correction. Age was not associated with dry eye symptoms in this population. [ J Refract Surg . 2019;35(3):161–168.]

PurposeTo test a new method to calculate the Intraocular Lens (IOL) power, that combines R Factor and ALxK methods, that we called Advance Lens Measurement Approach (ALMA).DesignRetrospective, Comparative, Observational study.SettingDepartment of Medicine and Surgery, University of Salerno, Italy.MethodsNinety one eyes of 91 patients previously treated with Photorefractive Keratectomy (PRK) or Laser-Assisted in Situ Keratomileusis (LASIK) that underwent phacoemulsification and IOL implantation in the capsular bag were analyzed. For 68 eyes it was possible to zero out the Mean Errors (ME) for each formula and for selected IOL models, in order to eliminate the bias of the lens factor (A-Costant). Main outcome, measured in this study, was the median absolute error (MedAE) of the refraction prediction.ResultsIn the sample with ME zeroed (68 eyes) both R Factor and ALxK methods resulted in MedAE of 0.67 D. For R Factor 33 eyes (48.53%) reported a refractive error ConclusionsBased on the results obtained from this study, ALMA method can improve R Factor and ALxK methods. This improvement is confirmed both by zeroing the mean error and without zeroing it.

Background/Aim. Enlargement of optical zone (OZ) diameter during laser in situ keratomileusis (LASIK) correction of myopia postoperatively improves the optical outcome, however, it also leads to the increased stroma tissue consumption - progressive corneal thinning. The aim of this investigation was to present the possibility of safe OZ enlargement without impairing the structural stability of the cornea, while obtaining an improved optical outcome with LASIK treatment of shortsightedness. Methods. Preoperative assessment of the cornea structure and prediction of the ablated stroma tissue consumption was conducted in 37 patients (74 eyes) treated for shortsightedness by means of the LASIK method. With the eyes that, according to their cornea structure, had the capacity for OZ diameter enlargement of 0.5 mm, LASIK treatment was performed within the wider OZ diameter of 7.0 mm compared to the standard 6.5 mm. The following two groups were formed, depending on the diameter of the utilized OZ: the group I (the eyes treated with the OZ 6.5 mm, n = 37) and the group II (the eyes treated with the OZ 7.0 mm, n = 37). Results. No significant difference in the observed structural parameters of the cornea was detected between the groups of patients treated with different OZ diameters. The values of all the parameters were significantly bellow the threshold values for the development of postoperative ectasia. Conclusion. Diameter enlargement of the treated OZ, if there is a preoperative cornea capacity for such enlargement, will not impair the postoperative stability of the cornea structure, and will significantly improve the optical outcome.

Astigmatism is corrected by either by toric lenses or surgical intervention including laser refractive surgery. Photorefractive keratectomy (PRK) is performed with the excimer laser which can accurately ablate corneal tissue to an exact depth with minimal disruption of surrounding tissue, it is done by removing the epithelial layer up to Bowman layer which then ablate with anterior stroma. Laser in situ keratomileusis (LASIK) is also performed with the excimer laser, but with creation a flap involving the stroma. This study aimed to compare the differences in visual outcome after 6 months between PRK and LASIK in treatment of astigmatism. It is a retrospective study in which 222 eyes of 115 patients (some of them had only astigmatism in one eye) who underwent laser refractive correction in Al-Hakeem General Hospital in Annajaf city to correct their astigmatismic refractive error were included in the study, 152 of astigmtismic eyes were corrected by LASIK (82 of female eyes and 70 of male eyes), 67 of astigmatismic eyes were corrected by PRK ( 35 of female eyes and 32 of male eyes). Patients were grouped into six groups according to their refractive error: G1: less than 1.0 dioptre, G2: 1.0-1.9 dioptres, G3: 2.0-2.9dioptres, G4: 3.0-3.9 dioptres, G5: 4.0-4.9dioptres and G6: 5.0-14.0 dioptres. The outcome of visual acuity was followed-up by autorefraction six months postoperatively and were grouped into five groups according to their visual outcome: a:emmetropia, b:no correction, c:undercorrection, d: increase the refractive error, e: overcorrection. The results shows that in those with astigmatism between 0.25-0.9 dioptre, no statistically significant association was found between outcome and type of operation (P=0.66). In those with astigmatism between 1.0-1.9 dioptres, statistically significant association was found between outcome and type of operation (p=0.023). In those with astigmatism between 2.0-2.9 dioptres, statistically significant association was found between outcome and type of operation (P=0.0009). In those with astigmatism between 3.0-3.9 dioptres, statistically significant association was found between outcome and type of operation (P=0.001). In those with astigmatism between 4.0-4.9 dioptres, no statistically significant association was found between outcome and type of operation (P=0.113). In those with astigmatism between 5.0-14.0 dioptres, no statistically significant association was found between outcome and type of operation (P=0.92). In conclusion, there is no statistical significant difference after 6 months of correction of astigmatism wither by LASIK or PRK at different levels of refractive error.

Cataracts are the leading cause of visual impairment and are primarily managed surgically.1 Cataract extraction is among the most common surgical interventions performed in the United States. The preferred method of cataract removal is extracapsular extraction, most commonly achieved by phacoemulsification (phaco) through small self-sealing corneal incisions. Laser-assisted in situ keratomileusis (LASIK) is the most commonly performed keratorefractive surgery in the United States.2 The procedure involves creating a corneal flap using a mechanical microkeratome or a femtosecond laser, reshaping the exposed corneal stroma using a tissue-ablating excimer laser, and repositioning the flap. Prevention of infection is important in both cataract and LASIK surgeries, and prophylactic use of topical antibacterials is recommended in both procedures.1,2 Besifloxacin is a chlorofluoroquinolone with a broad-spectrum bactericidal activity against aerobic and anaerobic bacteria.3–5 Besifloxacin ophthalmic suspension 0.6% (Besivance; Bausch & Lomb, Tampa, FL) incorporates a polycarbophil-based mucoadhesive polymer (DuraSite; InSite Vision, Alameda, CA) that prolongs the drug residence time on the ocular surface and improves bioavailability.6–9 Besifloxacin ophthalmic suspension is indicated for the treatment of bacterial conjunctivitis,10 but as with other topical antibacterial products, it is often used off-label for antibacterial prophylaxis in the surgical setting. Two prospective surveillance studies were conducted to evaluate the safety of besifloxacin ophthalmic suspension 0.6% when used as a prophylactic antibacterial agent by patients undergoing cataract or LASIK surgery, respectively. For comparative purposes, moxifloxacin ophthalmic solution 0.5% (Vigamox; Alcon Laboratories, Inc, Fort Worth, TX) was also evaluated. Moxifloxacin is an 8-methoxy fluoroquinolone antiinfective that has been used extensively for prophylaxis in the surgical setting with a history of good tolerability.11–13 It has once been described as the preferred treatment for surgical prophylaxis by many.14

AIM: To investigate the difference in kappa angle between sitting and supine positions during laser-assisted in situ keratomileusis (LASIK). METHODS: A retrospective study was performed on 395 eyes from 215 patients with myopia that received LASIK. Low, moderate, and high myopia groups were assigned according to diopters. The horizontal and vertical components of kappa angle in sitting position were measured before the operation, and in supine position during the operation. The data from the two positions were compared and the relationship between kappa angle and diopters were analyzed. RESULTS: Two hundred and twenty-three eyes (56.5%) in sitting position and 343 eyes (86.8%) in supine position had positive kappa angles. There were no significant differences in horizontal and vertical components of kappa angle in the sitting position or horizontal components of kappa angle in the supine position between the three groups (P>0.05). A significant difference in the vertical components of kappa angle in the supine position was seen in the three groups (P

PURPOSE To analyze the results of hyperopic patients treated with a peripheral presbyLASIK algorithm for the correction of presbyopia. METHODS The study included 44 eyes of 22 hyperopic patients treated with a peripheral presbyLASIK technique using a Technolas 217z excimer laser. Mean patient age was 56 years (range: 47 to 72 years), mean preoperative spherical equivalent refraction was +1.21±0.77 diopters (D) (range: +0.50 to +4.00 D), and mean spectacle near addition was 1.76±0.42 D (range: +1.00 to +2.75 D). The Peripheral Multifocal LASIK (PML) ablation pattern creates a multifocal corneal profile over a 6.5-mm diameter, performing the distance correction first in a 6-mm optical zone and then near correction in a 6.5-mm zone. Main outcome measures were uncorrected visual acuity (UCVA) and best spectacle-corrected visual acuity (BSCVA) for near and distance, spherical equivalent refraction, contrast sensitivity, and corneal aberrations. RESULTS Six months postoperatively, mean binocular UCVA was 1.06±0.13 for distance and 0.84±0.14 for near. Mean postoperative spherical equivalent refraction was –0.42 D (range: –1.12 to +0.87 D). Two (4.5%) eyes lost 1 line of BSCVA for distance and near vision, and 20 (45%) eyes gained 1 line of distance BSCVA. Contrast sensitivity decreased for 3, 6, 12, and 18 cycles/degree. Corneal aberration analysis showed a slight increase in coma and decrease in spherical aberration. CONCLUSIONS The peripheral presbyLASIK technique used in this study is a safe and efficient treatment that may improve functional near vision in presbyopic patients with low and moderate hyperopia (from +0.50 to +3.00 D). [J Refract Surg. 2008;24:494-500.] ABOUT THE AUTHORS From the Istituto Laser Microchirurgia Oculare, Brescia, Italy (Pinelli, Simonetto, Bacchi); the Research and Development Department, Vissum-Instituto Oftalmológico de Alicante, Alicante, Spain (Ortiz, Sala, Alió); and the Ophthalmology Department, Miguel Hernández University, Alicante, Spain (Alió). This study was supported in part by a grant of the Spanish Ministry of Health, Instituto Carlos III, Red Temática de Investigación en Oftalmologia, Subproyecto de Cirugia Refractiva y Calidad Visual (C03/13) and by a grant from the Spanish Generalitat Valenciana, ref: Grupos05/036 Grants and Support for scientific research and technological development in the Comunidad Valenciana for the year 2005. Dr Pinelli has a proprietary interest in the PML software. The remaining authors have no proprietary interest in the materials presented herein. Correspondence: Jorge L. Alió, MD, PhD, Research and Investigation Department, Instituto Oftalmológico Alicante, Vissum Corporation, Avda Denia s/n, Edificio Vissum, 03016 Alicante, Spain. Tel: 34 902 333 344; Fax: 34 965 160 468; E-mail: jlalio@vissum.com Received: September 13, 2006 Accepted: March 16, 2007 Posted online: October 31, 2007

OBJETIVO: Avaliar a eficácia e a segurança do LASIK (ceratotomia lamelar pediculada) hipermetrópico utilizando-se o sistema Ladar Vision de excimer laser. MÉTODOS: Foram analisados, retrospectivamente, 28 olhos de 17 pacientes com hipermetropia de +1,00 a +3,00 D (grupo 1) e 29 olhos de 18 pacientes com hipermetropia de + 3,25 a + 6,00 D (grupo 2), submetidos à cirurgia de LASIK, com o Sistema Ladar Vision de excimer laser. Acuidade visual sem correção, melhor acuidade visual corrigida e refração sob cicloplegia foram avaliadas em um, três e seis meses de pós-operatório. RESULTADOS: No grupo 1, o equivalente esférico médio pré-operatório, sob cicloplegia, era de + 2,14 ± 0,64 D, passando para + 0,44 ± 0,38 D no sexto mês de pós-operatório. No grupo 2, o equivalente esférico médio pré-operatório era de +4,26 ± 0,75 D, diminuindo para +1,14 ± 0,63 D no sexto mês de pós-operatório. 3,4% dos olhos do grupo 2 perderam três linhas de visão no primeiro mês de pós-operatório. No grupo 1, não houve perda de duas ou mais linhas de visão. CONCLUSÕES: O LASIK hipermetrópico com o sistema Ladar Vision mostrou-se procedimento eficaz e seguro. Pacientes do grupo 2 parecem estar sob maior risco de perda de linhas de melhor acuidade visual corrigida no pós-operatório. PURPOSE: To analyze the efficacy and safety of hyperopic laser in situ keratomileusis using the Ladar Vision excimer laser system. METHODS: Twenty-eight eyes of 17 patients with hyperopia from +1.00 to +3.00 D (group 1), and 29 eyes of 18 patients with hyperopia from +3.25 to +6.00 D (group 2) that had LASIK for hyperopia with the Ladar Vision, were retrospectively analyzed. Uncorrected visual acuity, best spectacle-corrected visual acuity and cycloplegic refraction were evaluated 1 , 3 and 6 months after surgery. RESULTS: In group 1, the mean preoperative cycloplegic spherical equivalent (SE) was +2.14 ± 0.64 D and 6-month postoperative SE was +0.44 ± 0.38 D. In group 2, the mean preoperative SE was +4.26 ± 0.75 D and the 6-month postoperative SE was +1.14 ± 0.63 D. 3.4% of the eyes in group 2 and none of the eyes in group 1 lost 2 or more lines of best spectacle-corrected visual acuity in the first postoperative month. CONCLUSIONS: LASIK with the Ladar Vision excimer laser system is an effective and safe procedure to correct hyperopia. Patients in group 2 appear to be at greater risk for loss of lines of best spectacle-corrected visual acuity.

Importance Patient-reported outcomes should be collected using validated questionnaires prior to and following laser in situ keratomileusis (LASIK) surgery. Objective To report the frequency of patient-reported visual symptoms, dry eye symptoms, satisfaction with vision, and satisfaction with LASIK surgery in the Patient-Reported Outcomes With LASIK (PROWL) studies. Design, Setting, and Participants The PROWL-1 and PROWL-2 studies were prospective, observational studies conducted from September 13, 2011, to June 27, 2014. The PROWL-1 study was a single–military center study of 262 active-duty Navy personnel 21 to 52 years of age. The PROWL-2 study was a study of 312 civilians 21 to 57 years of age conducted at 5 private practice and academic centers. The LASIK surgery and the postoperative care were performed based on the usual practice and clinical judgment at the site. Participants completed a self-administered, web-based questionnaire, preoperatively and postoperatively at 1 and 3 months (the PROWL-1 and -2 studies) and at 6 months (the PROWL-2 study). Exposures Participants underwent LASIK surgery for myopia, hyperopia, and/or astigmatism. Main Outcomes and Measures Visual symptoms (double images, glare, halos, and/or starbursts), dry eye symptoms, participant satisfaction (with vision and LASIK surgery), and clinical measures (visual acuity, refractive error, and slitlamp and posterior segment eye examination findings) were assessed preoperatively and at 1, 3, and 6 months postoperatively. Results A total of 262 participants were enrolled in the PROWL-1 study (mean [SD] age, 29.1 [6.1] years), and a total of 312 participants were enrolled in the PROWL-2 study (mean [SD] age, 31.5 [7.3] years). Visual symptoms and dissatisfaction with vision were common preoperatively. Overall, the prevalence of visual symptoms and dry eye symptoms decreased, although a substantial percentage of participants reported new visual symptoms after surgery (43% [95% CI, 31%-55%] from the PROWL-1 study and 46% [95% CI, 33%-58%] from the PROWL-2 study at 3 months). The percentages of participants in the PROWL-1 study with normal Ocular Surface Disease Index scores were 55% (95% CI, 48%-61%) at baseline, 66% (95% CI, 59%-72%) at 3 months, and 73% (95% CI, 67%-79%) at 6 months. The percentages of participants in the PROWL-2 study with normal Ocular Surface Disease Index scores were 44% (95% CI, 38%-50%) at baseline and 65% (95% CI, 59%-71%) at 3 months. Of those participants who had normal scores at baseline in both the PROWL-1 and -2 studies, about 28% (95% CI, 19%-37%) had mild, moderate, or severe dry eye symptoms at 3 months. While most participants were satisfied, the rates of dissatisfaction with vision ranged from 1% (95% CI, 0%-4%) to 4% (95% CI, 2%-7%), and the rates of dissatisfaction with surgery ranged from 1% (95% CI, 0%-4%) to 2% (95% CI, 1%-5%). Conclusions and Relevance The systematic administration of a questionnaire to patients who have undergone LASIK surgery is a new approach to assess symptoms and satisfaction. Our findings support the need for adequate counseling about the possibility of developing new symptoms after LASIK surgery.

Objective To determine whether procedure room temperature or humidity during LASIK affect refractive outcomes in a large patient sample. Design Retrospective cohort study. Participants A total of 202 394 eyes of 105 712 patients aged 18 to 75 years who underwent LASIK at an Optical Express, Inc., location in their United Kingdom and Ireland centers from January 1, 2008, to June 30, 2011, who met inclusion criteria. Methods Patient age, gender, flap creation technique, pre- and 1-month post-LASIK manifest refraction, and ambient temperature and humidity during LASIK were recorded. Effect size determination and univariate and multivariate analyses were performed to characterize the relationships between LASIK procedure room temperature and humidity and postoperative refractive outcome. Main Outcome Measures One month post-LASIK manifest refraction. Results No clinically significant effect of procedure room temperature or humidity was found on LASIK refractive outcomes. When considering all eyes in our population, an increase of 1°C during LASIK was associated with a 0.003 diopter (D) more hyperopic refraction 1 month postoperatively, and an increase in 1% humidity was associated with a 0.0004 more myopic refraction. These effect sizes were the same or similar when considering only myopic eyes, only hyperopic eyes, and subgroups of eyes stratified by age and preoperative refractive error. Conclusions Neither procedure room temperature nor humidity during LASIK were found to have a clinically significant relationship with postoperative manifest refraction in our population. Financial Disclosure(s) Proprietary or commercial disclosure may be found after the references.

PURPOSE. To report and compare outcomes of vitreoretinal surgery for repair of retinal detachment in myopic patients with and without previous laser-assisted in situ keratomileusis (LASIK). METHODS. This is a descriptive retrospective observational study with a control group for comparison that consisted of the analysis of clinical and surgical charts of patients who underwent vitreoretinal procedures for retinal detachment at the Fundación Oftalmológica Nacional between January 1995 and December 2002. The authors identified those myopic patients who had previous history of LASIK and an age- and myopia-matched control group without refractive surgery. RESULTS. The sample contains 24 myopic eyes of 22 patients with previous LASIK and 23 myopic eyes without previous LASIK in the control group, matched by age and myopia. Mean refractive error was -9.4 D before LASIK for the cases group and -11.2 for the control group. Poor preoperative best-corrected visual acuity was present in 71% of cases and 61% of controls (p=0.489). Macula off retinal detachment was found in 17 eyes in both groups. Five eyes required at least two procedures, achieving 91% (20 eyes) reattachments at the end of follow-up in each group. Final best-corrected visual acuity was better than 20/100 in 15 eyes (62.5%) in the LASIK group and 17 eyes (74%) in the control group (p=0.659). CONCLUSIONS. Retinal detachment in patients with previous myopic LASIK has similar characteristics as in myopic patients without refractive surgery. Current vitreoretinal surgery is of good prognosis as the retina was successfully reattached in most cases in both groups. © Wichtig Editore, 2006.

Aim: To evaluate changes in corneal polarisation properties and their influence on peripapillary retinal nerve fibre layer (RNFL) thickness measurements after laser assisted in situ keratomileusis (LASIK) by means of scanning laser polarimetry (SLP) with variable corneal polarisation compensator (VCC) in normal white subjects. Methods: SLP was performed by means of GDx VCC on 32 eyes of 32 normal subjects who underwent LASIK for ametropia correction. Corneal polarisation axis and magnitude and RNFL thickness were measured before and 8 days after LASIK. RNFL thickness data and corneal polarimetric data of one randomly selected eye per subject were analysed by the Wilcoxon signed ranks test. Correlations between corneal ablation depth, corneal polarimetric changes, and RNFL thickness changes were investigated using Spearman’s rho test. Results: The corneal polarisation axis significantly shifted from 15.1° (17.0°) to 6.9° (12.9°) (p = 0.00006) after LASIK and this change showed a strong correlation with corneal ablation depth (rho = −0.7, p = 0.00002). Among GDx parameters, TSNIT, SUP, and SD showed significant changes after LASIK and for SUP and SD these changes were well correlated with the shift in corneal polarisation axis (rho = 0.54, p = 0.03 and rho = 0.45, p = 0.01, respectively). SUP and SD changes were neutralised after compensating for corneal polarimetric changes but not TSNIT changes. NFI, a discriminating parameter, was found to be affected after LASIK only after compensating for corneal polarimetric changes. Conclusions: LASIK induces a shift in corneal polarisation axis which is responsible for inaccuracies in RNFL thickness measurements. A customised compensation for corneal polarimetric changes after LASIK allows normalisation of some of the thickness parameters except for TSNIT and NFI.

Purpose To evaluate the efficacy and safety of topographically guided excimer laser photoablation to retreat unsuccessful myopic and hyperopic photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK). Setting Eye Clinic, San Salvatore Hospital, University of L'Aquila, L'Aquila, Italy. Methods At least 3 months after primary PRK (Group A) or primary LASIK (Group B), 48 eyes of 42 patients were submitted to PRK or LASIK enhancements. The eyes were treated with an excimer laser linked to a computerized videokeratography unit with a topographically supported customized ablation workstation. Results The mean follow-up was 27.8 months ± 8.2 (SD). In Group A, the uncorrected visual acuity (UCVA) changed from 0.5 ± 0.7 logarithm of the minimum angle of resolution (logMAR) (range 20/600 to 20/200) to 0.1 ± 0.7 logMAR (range 20/60 to 20/20); the mean best spectacle-corrected visual acuity (BSCVA) changed from 0.1 ± 0.7 logMAR (range 20/50 to 20/20) to 0 ± 0.7 logMAR (range 20/50 to 20/20) after the enhancement. In Group B, the UCVA changed from 0.7 ± 0.8 logMAR (range 20/600 to 20/40) to 0.1 ± 0.7 logMAR (range 20/40 to 20/20); the mean BSCVA improved from 0.2 ± 0.8 logMAR (range 20/30 to 20/20) to 0 ± 1.3 logMAR (range 20/25 to 20/20) after surgery. Conclusions The enhancements using topographically guided excimer laser photoablation with a topographically supported customized ablation method resulted in satisfactory and stable visual outcome with good safety and efficacy after unsuccessful PRK and LASIK.

To describe a case of choroidal neovascularization (CNV) after laser in situ keratomileusis (LASIK) following penetrating keratoplasty (PK).Case report.A 30-year-old man underwent PK in both eyes for bilateral keratoconus in 1997. Two years later, best-corrected visual acuity (BCVA) was 20/40 (-6=-4.50 x 170 degrees ) in RE and 20/20 (-1.50=-0.50 x 90 degrees ) in LE. To reduce the anisometropic defect, LASIK was performed in RE. After surgery, the refractive defect in RE reduced to -1.75 x 125 degrees and BCVA improved to 20/25. Six months after LASIK the patient presented loss of vision and metamorphopsia in RE due to choroidal neovascularization. BCVA was reduced to 20/200. Photodynamic therapy was performed in RE; 1 year later BCVA was stable at 20/200.Vitreoretinal complications after LASIK occur rarely. The potential relationship between CNV and LASIK is discussed.

Objetivo: Descrever as complicações per e pós-operatórias ocorridas durante o uso inicial de dois microceratótomos automatizados na realização de LASIK. Métodos: Estudo retrospectivo das primeiras cirurgias realizadas com dois microceratótomos automatizados, sendo 70 olhos de 54 pacientes utilizando o microceratótomo da Chiron® modelo Automated Corneal Shaper (ACS), no período de abril de 1997 a abril de 1998 e 100 olhos de 82 pacientes com o microceratótomo automatizado Moria® Carriazo-Barraquer (CB), durante o período de fevereiro de 1999 a junho de 1999. A fotoablação foi realizada com excimer laser de fluoreto de argônio de 193 nm da Summit modelo Apex Plus®. Foram avaliadas as complicações per e pós-operatórias até um mês de seguimento. Resultados: A fotoablação não foi realizada em 3 casos (4,3%) usando-se o microceratótomo ACS e em 1 caso (1%) usando o microceratótomo CB. As complicações mais freqüentemente encontradas com o ACS foram: falha no retorno automatizado do microceratótomo (7,1%), ceratectomia parcial (flap incompleto): 4,3%, presença de dobras estromais (14,3%), desepitelização central (4,3%) e crescimento epitelial na interface (4,3%). Já com o CB, foram encontrados: flap descentralizado (3%), desepitelização central (5%), dobras estromais (28%) e síndrome das Areias de Sahara (6%). Conclusões: O uso inicial de ambos microceratótomos foi relacionado a considerável índice de complicações per e pós-operatórias, não levando necessariamente à perda de visão. Maior conhecimento clínico das alterações ocorridas com o uso destes instrumentos, bem como maior experiência na sua utilização podem diminuir a ocorrência de complicações. Purpose: To describe per- and postoperative complications which occurred with the first use of two automated microkeratomes for the performance of LASIK. Methods: Retrospective study of first surgeries performed with two automated microkeratomes. Seventy eyes from 54 patients using Chiron's® microkeratome, Automated Corneal Shaper (ACS) model, from April 1997 to April 1998 and 100 eyes from 82 patients using automated microkeratome Moria® Carriazo-Barraquer (CB), from February 1999 to June 1999. Refractive ablation was performed with the Summit Apex Plus Excimer Laser (193 nm). We evaluated the per- and postoperative complications up to one month of follow-up. Results: Photoablation was not performed in three cases (4.3%) using ACS microkeratome and in one case (1%) using CB microkeratome. Most frequent complications found with ACS were: failure of automated return of microkeratome (7.1%), partial keratotomy (4.3%), presence of stromal folds (14.3%), central de-epithelialization (4.3%). With CB there were: descentered flap (3%), central desepitheliazation (5%), stromal folds (28%) and Sahara Sands syndrome (6%). Conclusions: Initial use of both microkeratomes was related to important per- and postoperative complications, which did not lead to loss of vision. Clinical knowledge of the alterations which occurred with the use of these instruments and a better experience of their utilization may reduce these complications. Universidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Departamento de Oftalmologia UNIFESP, EPM, Depto. de Oftalmologia SciELO

PURPOSE: To compare the refractive outcomes and aberration data analysis of wavefront-optimized (WFO) ablation and topography-guided Contoura ablation (TGCA) (Contoura on the WaveLight laser; WaveLight GmbH, Erlangen, Germany) in patients who had laser-assisted in situ keratomileusis (LASIK) for myopia or myopic astigmatism. METHODS: In this comparative contralateral eye study, patients who underwent LASIK with TGCA in one eye and with WFO ablation in the fellow eye were analyzed. Aberration measurements and corneal topography were analyzed using the WaveLight Oculyzer II diagnostic device (Alcon Laboratories, Inc., Fort Worth, TX). Total corneal higher order aberrations (HOAs) including vertical and oblique astigmatism (Z 2 2 , Z 2 −2 ), coma (Z 3 1 , Z 3 −1 ), trefoil (Z 3 3 , Z 3 −3 ), spherical aberration, and Q value were analyzed. These measurements were taken preoperatively and 3 months postoperatively. RESULTS: This study comprised 32 patients. There were no significant differences between both procedures according to postoperative uncorrected and corrected distance visual acuity values, refractive errors, and manifest refraction spherical equivalents within ±0.50 diopters (D) of emmetropia ( P > .05). The preoperative corneal HOAs and Q values were also similar between the groups ( P > .05). At 3 months postoperatively, the vertical and horizontal coma values in the WFO ablation group were statistically significantly higher compared to the TGCA group ( P = .013 and .020, respectively). Less stromal tissue was ablated in the TGCA group compared to the WFO ablation group ( P < .001). CONCLUSIONS: Although WFO ablation and TGCA protocols had statistically similar visual outcomes, the TGCA protocol was associated with a significantly lower induction in vertical and horizontal coma and smaller amount of tissue ablation compared to WFO ablation. [ J Refract Surg. 2019;35(4):222–229.]