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1.
Zhonghua Yan Ke Za Zhi ; 57(4): 268-276, 2021 Apr 11.
Artigo em Chinês | MEDLINE | ID: mdl-33832051

RESUMO

Objective: To investigate the repair of subepithelial nerve fibers in different areas of the cornea and the difference of corneal transparency 12 months after small incision lenticule extraction (SMILE), femtosecond laser in situ keratomileusis (FS-LASIK) and excimer laser in situ keratomileusis (LASEK) in high myopia. Methods: A cohort study. From June 2018 to October 2019, 30 patients with high myopia (60 eyes) were selected for corneal refractive surgery in the Department of Ophthalmology, Affiliated Hospital of Qingdao University, including 16 females (32 eyes) and 14 males (28 eyes). According to the mode of operation, the patients were divided into the SMILE group (n=10), FS-LASIK group (n=11) and LASEK group (n=9). The repair of subepithelial nerves in different areas of the cornea was observed by laser confocal microscopy 12 months after operation,and the morphological parameters were analyzed by ACCMetrics software. The parameters included corneal nerve fiber density (CNFD), corneal nerve branch density (CNBD), corneal nerve fiber length (CNFL), corneal nerve fiber total branch density (CTBD) and corneal nerve fiber width. The Pentacam anterior segment analyzer was used to measure the optical density of the cornea in different diameters. The nerve fiber parameters and corneal optical density were compared by random block analysis of variance, and multiple comparisons were performed between groups by the Turkey test. Results: Twelve months after operation, there was no significant difference in the CNFD among the three groups(all P>0.05). The CNBD around the upper corneal incision in the SMILE group, FS-LASIK group and LASEK group was (7.81±7.93), (9.61±7.18) and (21.25±15.55) branches/mm2, respectively. The CTBD was (22.00±16.02), (24.44±11.42) and (54.37±22.13) branches/mm2, respectively. The values in the LASEK group significantly differed from the other two groups (HSD=2.823, -3.010, 3.053, -3.048, P<0.01). The CNFL was (9.19±3.25), (12.88±3.52) and (15.75±2.36) mm/mm2, respectively. The value in the SMILE group was significantly different (HSD=-3.151, -4.418; P<0.0l). The corneal optical density after SMILE was 13.16±0.72 in the 0-6 mm diameter area(HSD=-4.164, -4.489; P<0.01), 16.12±3.18 in the 6-12 mm diameter area(HSD=-3.918, -3.493;P<0.01) and 14.06±1.36 in the total diameter (HSD=-6.031, -5.519;P<0.01), which differed significantly from the other two groups. Conclusions: Twelve months after SMILE for high myopia, the nerve repair around the superior corneal incision is slightly worse than that after FS-LASIK and LASEK, but the nerve repair in other areas has some advantages, and the corneal transparency is better. (Chin J Ophthalmol, 2021, 57:268-276).


Assuntos
Ceratomileuse Assistida por Excimer Laser In Situ , Miopia , Estudos de Coortes , Córnea/cirurgia , Substância Própria , Feminino , Humanos , Lasers de Excimer , Masculino , Miopia/cirurgia , Acuidade Visual
2.
Medicine (Baltimore) ; 100(14): e25366, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33832118

RESUMO

ABSTRACT: To compare and analyze the postoperative 1-year outcomes of laser refractive surgery (LRS) alone vs LRS with laser asymmetric keratectomy (LAK), in patients with myopia, for preventing and resolving LRS complications.This retrospective study compared the preoperative and 1-year postoperative outcomes between the control and comparison groups using a sum of deviations in corneal thickness in 4 directions >80 µm. The control group included 41 patients with myopia (41 eyes) who underwent LRS. The comparison group included 33 patients (33 eyes) who received LAK-linked LRS. Age, spherical equivalent (SE), sphere, cylinder, uncorrected distance visual acuity (UDVA), pupil size, kappa angle, central corneal thickness, corneal irregularity in the 3.0 mm zone on Orbscan maps (SUM), distance between the maximum posterior elevation (best-fit-sphere) and the visual axis (DISTANCE), postoperative blurring scores, frequency of postoperative myopic regression, and efficiency index were compared.Preoperative age (P = .198), SE (P = .686), sphere (P = .562), cylinder (P = .883), UDVA (P = .139), pupil size (P = .162), kappa angle (P = .807), central corneal thickness (P = .738), corneal irregularity (P = .826), SUM (P = .774), and DISTANCE (P = .716) were similar between the 2 groups. The 1-year postoperative SE (P = .024), sphere (P = .022), corneal irregularity (P = .033), SUM (P = .000), DISTANCE (P = .04), blurring scores (P = .000), and frequency of postoperative myopic regression (P = .004) were significantly decreased in the comparison group compared to the control group. UDVA (P = .014) and the efficiency index (P = .035) were higher in the comparison group.LAK with LRS improved corneal symmetry by reducing the SUM and DISTANCE. UDVA and efficiency index were also improved and blurring and myopic regression were reduced postoperatively.


Assuntos
Córnea/cirurgia , Cirurgia da Córnea a Laser/efeitos adversos , Ceratomileuse Assistida por Excimer Laser In Situ/efeitos adversos , Miopia/cirurgia , Adulto , Estudos de Casos e Controles , Terapia Combinada , Córnea/fisiopatologia , Paquimetria Corneana/estatística & dados numéricos , Cirurgia da Córnea a Laser/métodos , Feminino , Humanos , Ceratomileuse Assistida por Excimer Laser In Situ/métodos , Masculino , Miopia/diagnóstico , Miopia/fisiopatologia , Período Pós-Operatório , Refração Ocular/fisiologia , Estudos Retrospectivos , Resultado do Tratamento , Transtornos da Visão/epidemiologia , Transtornos da Visão/etiologia , Acuidade Visual/fisiologia
3.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 46(2): 162-168, 2021 Feb 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-33678653

RESUMO

OBJECTIVES: To investigate angle Kappa and diopter distribution in myopic patients and the changes of angle Kappa and corneal morphology after Sub-Bowman-Keratomileusis (SBK), and to analyze the effects of the surgery on corneal morphologic changes and the patients' near fixation characteristics. METHODS: The clinical data of 134 myopic patients (268 eyes) undergoing SBK from August 2015 to August 2016 were retrospectively analyzed. Angle Kappa, corneal curvature in the central corneal region of 3 mm, and post-corneal Diff value were measured by Orbscan IIz Corneal Topography System before operation, 1 month and 6 months after operation. According to the values of angle Kappa before SBK, the patients were divided into 2 groups: the large K group (angle Kappa≥5°, 71 eyes) and the small K group (angle Kappa<5°, 197 eyes). Correlation analysis of the factors influencing angle Kappa at 6 months after operation was performed. RESULTS: In the large K group, angle Kappa was (5.67±0.65)°, spherical equivalent was (-4.84±2.32) D, and angle Kappa was decreased after operation (both P<0.05) with the increased decreasing range over time. In the small K group, angle Kappa was (3.51±1.08)°, spherical equivalent was (-5.78±2.63) D, angle Kappa was increased after operation with decreased increasing range over time, and the difference was statistically significant between 6 months after operation and before operation (P<0.05).The post-corneal Diff value of the 2 groups was increased after operation (all P<0.001), and was decreased from 1 month to 6 months after surgery. The corneal curvature in the central corneal region of 3 mm of the 2 groups 1 month after operation was decreased significantly (both P<0.001). From 1 month to 6 months after operation, the corneal curvature of the large K group tended to be stable, while the corneal curvature of the small K group tended to increase. There was no significant correlation between the changes of angle Kappa 6 months after operation and the changes of the corneal central curvature or the post-corneal Diff value (both P>0.05), but the changes of angle Kappa 6 months after operation was positively correlated with corneal cutting thickness (rlarge K group=0.398, rsmall K group=0.218, both P<0.05) and it was negatively correlated with preoperative diopter (rlarge K group=-0.283, rsmall K group=-0.233, both P<0.05). CONCLUSIONS: The angle Kappa is decreased in low-moderate myopia patients with large angle Kappa, while is increased in high myopia patients with small angle Kappa after SBK. Myopia patients after SBK will look for the new balance of the binocular accommodation and vergence function for improving the comfort in the near-work situations.


Assuntos
Ceratomileuse Assistida por Excimer Laser In Situ , Miopia , Córnea/cirurgia , Humanos , Miopia/cirurgia , Refração Ocular , Estudos Retrospectivos
5.
Exp Eye Res ; 203: 108428, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33400926

RESUMO

Dry eye is the most common complication after refractive surgery, especially after laser in situ keratomileusis (LASIK), in which nerves may be cut when making the corneal flap. Nerve growth factor (NGF) has been demonstrated to stimulate corneal sensitivity and nerve regeneration and NGF has been suggested as a potential treatment for dry eye disease (DED). Hence, this study aimed to investigate the effect of NGF on corneal nerve regeneration, sensitivity and dry eye symptoms after LASIK, compared to hycosan and normal saline (NS) treatments. Thirty-eight New Zealand white rabbits that underwent LASIK procedures were randomly assigned to three groups. Each group underwent NGF, hycosan, and NS treatment. The nerve densities and the number of corneal sub-basal and superficial stromal nerves were measured with confocal microscopy, and the results were compared before surgery and at one month and three months postoperatively. Corneal sensitivity was assessed with an esthesiometer. The tear breakup time (TBUT) was recorded to check for signs of dry eye. The whole corneas of the experimental animals were excised at three months after the surgery for immunohistochemically analysis. After LASIK, treatment with NGF significantly accelerated the recovery of sub-basal and superficial stromal nerve densities and the numbers, compared to hycosan and NS treatments at one month and three months postoperatively (NGF vs. hycosan, P < 0.01 each; NGF vs. NS, P < 0.01 each). The recovery of corneal sensitivity was significantly enhanced in the NGF group compared to the hycosan or NS treatment groups after surgery (P < 0.05). Also, the TBUT data showed a statistically significant longer time in the NGF group at one month, and three months postoperatively (P < 0.05). Immunofluorescence analysis showed the nerve fiber quantity of the NGF group was larger than in the hycosan and NS groups. Taken together, the experimental results suggested that mNGF had an obvious effect on promoting corneal nerve repairing and the potential to improve dry eye in different periods following LASIK.


Assuntos
Córnea/inervação , Síndromes do Olho Seco/tratamento farmacológico , Ceratomileuse Assistida por Excimer Laser In Situ/efeitos adversos , Fator de Crescimento Neural/uso terapêutico , Regeneração Nervosa/efeitos dos fármacos , Nervo Oftálmico/fisiologia , Administração Oftálmica , Animais , Substância Própria/cirurgia , Síndromes do Olho Seco/etiologia , Síndromes do Olho Seco/fisiopatologia , Feminino , Ceratomileuse Assistida por Excimer Laser In Situ/métodos , Masculino , Microscopia Confocal , Miopia/cirurgia , Soluções Oftálmicas , Coelhos , Lágrimas/metabolismo
6.
BMC Ophthalmol ; 21(1): 23, 2021 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-33422053

RESUMO

BACKGROUND: To evaluate clinical outcomes after full-thickness astigmatic keratotomy (FTAK) combined with small-incision lenticule extraction (SMILE) in eyes with high astigmatism. METHODS: This study comprised 75 eyes of 43 patients with over 4.0 diopters (D) of astigmatism who were treated with SMILE after FTAK. Visual acuities and refractive measurements were evaluated at 1 month after FTAK, and 1, 6, 12, and 24 months after SMILE. Vector analysis of the astigmatic changes was performed using the Alpins method. RESULTS: Twenty-four months after the combined procedure, the average spherical equivalent was reduced from - 6.56 ± 2.38 D to - 0.36 ± 0.42 D (p < 0.001). The uncorrected and corrected distance visual acuities improved from 1.54 ± 5.53 to - 0.02 ± 0.09 and from - 0.03 ± 0.07 D to - 0.07 ± 0.08 D (both p < 0.001), respectively. The preoperative mean astigmatism was - 5.48 ± 1.17 D, which was reduced to - 2.27 ± 0.97 D and - 0.34 ± 0.26 D at 1 month after FTAK and 24 months after SMILE, respectively (p < 0.001). The surgically-induced astigmatism after FTAK, SMILE, and FTAK and SMILE combined was 3.38 ± 1.18 D, 2.22 ± 0.84 D, and 5.39 ± 1.20 D, respectively. Furthermore, the correction index of FTAK, SMILE, and FTAK and SMILE combined was 0.63 ± 0.17, 0.90 ± 0.40, and 0.98 ± 0.06, respectively. There were no intraoperative or postoperative complications. CONCLUSION: Our surgical procedure combining FTAK and SMILE showed good and stable clinical outcomes during two-year follow-up for the treatment of high astigmatism.


Assuntos
Astigmatismo , Cirurgia da Córnea a Laser , Ceratomileuse Assistida por Excimer Laser In Situ , Miopia , Adolescente , Adulto , Astigmatismo/cirurgia , Substância Própria , Feminino , Humanos , Masculino , Miopia/cirurgia , Refração Ocular , Adulto Jovem
7.
Curr Opin Ophthalmol ; 32(1): 45-53, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33122489

RESUMO

PURPOSE OF REVIEW: Corneal refractive surgery has achieved spectacle-free vision for millions of patients, but this aging population is now developing cataracts. Many of these patients may wish to avoid reliance on glasses after cataract surgery. Presbyopia-correcting intraocular lenses (IOLs) offer a solution, but corneal changes after refractive surgery may compound higher order aberrations and dysphotopic symptoms associated with these IOLs. This review aims to discuss potential factors that could aid in determining suitable postkeratorefractive candidates for presbyopia-correcting IOLs. RECENT FINDINGS: Studies investigating which preoperative measures influence outcomes are lacking. The few studies that have examined presbyopia-correcting IOLs in postkeratorefractive patients report that satisfactory outcomes are possible. However, recommendations for preoperative thresholds appear limited to expert opinion and studies involving virgin corneas. SUMMARY: As the number of presbyopia-correcting IOLs and postkeratorefractive patients grows, continued investigation into relevant preoperative factors and appropriate IOLs is required to make evidence-based decisions. The current literature shows that with rigorous counseling and appropriate patient selection, presbyopia-correcting IOLs can provide postkeratorefractive patients with satisfactory results and spectacle independence. In addition, the development of postoperative modifiable IOLs may prove to be the preferred option.


Assuntos
Implante de Lente Intraocular , Lentes Intraoculares Multifocais , Presbiopia/cirurgia , Percepção de Profundidade/fisiologia , Humanos , Ceratomileuse Assistida por Excimer Laser In Situ/efeitos adversos , Ceratectomia Fotorrefrativa/efeitos adversos , Presbiopia/etiologia , Presbiopia/fisiopatologia , Acuidade Visual/fisiologia
8.
Curr Opin Ophthalmol ; 32(1): 13-18, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33196544

RESUMO

PURPOSE OF REVIEW: There are several different approaches to handling regular and irregular astigmatism during cataract surgery, but still much debate on which solutions are most effective given unique patient circumstances. In this review, we examine recent literature and studies to highlight some of the most effective ways to plan preoperatively, manage regular and irregular astigmatism during cataract surgery, as well as managing postoperative complications. RECENT FINDINGS: Recent developments in technology have provided increased courses of action for astigmatism management during cataract surgery. Additional options of toric IOLs with presbyopic platforms, light adjustable lenses, intraocular pinhole lenses, online technological tools and platforms, wavefront or topographic laser technology, and phototherapeutic keratectomy are all effective solutions to managing regular and irregular astigmatism. In this review, we will explore optimal approaches for unique situations. SUMMARY: With increased technology, research, and methods, correcting regular and irregular astigmatism during cataract surgery is achievable in most patients. With in-depth preoperative planning, analysis of patient-specific factors, and a tailored approach, surgeons can obtain excellent uncorrected vision for patients.


Assuntos
Astigmatismo/cirurgia , Implante de Lente Intraocular/métodos , Facoemulsificação/métodos , Astigmatismo/fisiopatologia , Humanos , Ceratomileuse Assistida por Excimer Laser In Situ , Ceratectomia Fotorrefrativa , Pseudofacia/fisiopatologia , Refração Ocular/fisiologia , Acuidade Visual/fisiologia
9.
Cochrane Database Syst Rev ; 12: CD012687, 2020 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-33336797

RESUMO

BACKGROUND: Refractive errors (conditions in which the eye fails to focus objects accurately on the retina due to defects in the refractive system), are the most common cause of visual impairment. Myopia, hyperopia, and astigmatism are low-order aberrations, usually corrected with spectacles, contact lenses, or conventional refractive surgery. Higher-order aberrations (HOAs) can be quantified with wavefront aberration instruments and corrected using wavefront-guided or wavefront-optimized laser surgery. Wavefront-guided ablations are based on preoperative measurements of HOAs; wavefront-optimized ablations are designed to minimize induction of new HOAs while preserving naturally occurring aberrations. Two wavefront procedures are expected to produce better visual acuity than conventional procedures. OBJECTIVES: The primary objective was to compare effectiveness and safety of wavefront procedures, laser-assisted in-situ keratomileusis (LASIK) or photorefractive keratectomy (PRK) or laser epithelial keratomileusis (LASEK) versus corresponding conventional procedures, for correcting refractive errors in adults for postoperative uncorrected visual acuity, residual refractive errors, and residual HOAs. The secondary objective was to compare two wavefront procedures. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL, which contains the Cochrane Eyes and Vision Trials Register; 2019, Issue 8); Ovid MEDLINE; Ovid Embase; Latin American and Caribbean Health Sciences (LILACS); the ISRCTN registry; ClinicalTrials.gov and the WHO ICTRP. The date of the search was 6 August 2019. We imposed no restrictions by language or year of publication. We used the Science Citation Index (September 2013) and searched the reference lists of included trials to identify additional relevant trials. SELECTION CRITERIA: We included randomized controlled trials (RCTs) comparing either wavefront modified with conventional refractive surgery or wavefront-optimized with wavefront-guided refractive surgery in participants aged ⪰ 18 years with refractive errors. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methodology. MAIN RESULTS: We identified 33 RCTs conducted in Asia, Europe and United States, totaling 1499 participants (2797 eyes). Participants had refractive errors ranging from high myopia to low hyperopia. Studies reported at least one of the following review-specific outcomes based on proportions of eyes: with uncorrected visual acuity (UCVA) of 20/20 or better, without loss of one or more lines of best spectacle-corrected visual acuity (BSCVA), within ± 0.50 diopters (D) of target refraction, with HOAs and adverse events. Study characteristics and risk of bias Participants were mostly women, mean age 29 and 53 years, and without previous refractive surgery, ocular pathology or systemic comorbidity. We could not judge risks of bias for most domains of most studies. Most studies in which both eyes of a participant were analyzed failed to account for correlations between two eyes in the analysis and reporting of outcomes. Findings For the primary comparison between wavefront (PRK or LASIK or LASEK) and corresponding conventional procedures, 12-month outcome data were available from only one study of PRK with 70 participants. No evidence of more favorable outcomes of wavefront PRK on proportion of eyes: with UCVA of 20/20 or better (risk ratio [RR] 1.03, 95% confidence interval (CI) 0.86 to 1.24); without loss of one or more lines of BSCVA (RR 0.94, 95% CI 0.81 to 1.09); within ± 0.5 D of target refraction (RR 1.03, 95% CI 0.86 to 1.24); and mean spherical equivalent (mean difference [MD] 0.04, 95% CI -0.11 to 0.18). The evidence for each effect estimate was of low certainty. No study reported HOAs at 12 months. At six months, the findings of two to eight studies showed that overall effect estimates and estimates by subgroup of PRK or LASIK or LASEK were consistent with those for PRK at 12 month, and suggest no difference in all outcomes. The certainty of evidence for each outcome was low. For the comparison between wavefront-optimized and wavefront-guided procedures at 12 months, the overall effect estimates for proportion of eyes: with UCVA of 20/20 or better (RR 1.00, 95% CI 0.99 to 1.02; 5 studies, 618 participants); without loss of one or more lines of BSCVA (RR 0.99, 95% CI 0.96 to 1.02; I2 = 0%; 5 studies, 622 participants); within ± 0.5 diopters of target refraction (RR 1.02, 95% CI 0.95 to 1.09; I2 = 33%; 4 studies, 480 participants) and mean HOAs (MD 0.03, 95% CI -0.01 to 0.07; I2 = 41%; 5 studies, 622 participants) showed no evidence of a difference between the two groups. Owing to substantial heterogeneity, we did not calculate an overall effect estimate for mean spherical equivalent at 12 months, but point estimates consistently suggested no difference between wavefront-optimized PRK versus wavefront-guided PRK. However, wavefront-optimized LASIK compared with wavefront-guided LASIK may improve mean spherical equivalent (MD -0.14 D, 95% CI -0.19 to -0.09; 4 studies, 472 participants). All effect estimates were of low certainty of evidence. At six months, the results were consistent with those at 12 months based on two to six studies. The findings suggest no difference between two wavefront procedures for any of the outcomes assessed, except for the subgroup of wavefront-optimized LASIK which showed probable improvement in mean spherical equivalent (MD -0.12 D, 95% CI -0.19 to -0.05; I2 = 0%; 3 studies, 280 participants; low certainty of evidence) relative to wavefront-guided LASIK. We found a single study comparing wavefront-guided LASIK versus wavefront-guided PRK at six and 12 months. At both time points, effect estimates consistently supported no difference between two procedures. The certain of evidence was very low for all estimates. Adverse events Significant visual loss or optical side effects that were reported were similar between groups. AUTHORS' CONCLUSIONS: This review suggests that at 12 months and six months postoperatively, there was no important difference between wavefront versus conventional refractive surgery or between wavefront-optimized versus wavefront-guided surgery in the clinical outcomes analyzed. The low certainty of the cumulative evidence reported to date suggests that further randomized comparisons of these surgical approaches would provide more precise estimates of effects but are unlikely to modify our conclusions. Future trials may elect to focus on participant-reported outcomes such as satisfaction with vision before and after surgery and effects of remaining visual aberrations, in addition to contrast sensitivity and clinical outcomes analyzed in this review.


Assuntos
Aberrações de Frente de Onda da Córnea/cirurgia , Ceratectomia Subepitelial Assistida por Laser/métodos , Ceratomileuse Assistida por Excimer Laser In Situ/métodos , Lasers de Excimer/uso terapêutico , Ceratectomia Fotorrefrativa/métodos , Adulto , Astigmatismo/cirurgia , Feminino , Humanos , Hiperopia/cirurgia , Ceratectomia Subepitelial Assistida por Laser/efeitos adversos , Ceratomileuse Assistida por Excimer Laser In Situ/efeitos adversos , Masculino , Pessoa de Meia-Idade , Miopia/cirurgia , Ceratectomia Fotorrefrativa/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento , Acuidade Visual
10.
Medicine (Baltimore) ; 99(45): e21563, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33157908

RESUMO

BACKGROUND: Previous studies examining the safety and efficacy of Q-value-guided laser-assisted in situ keratomileusis (LASIK) for treating myopia have yielded inconsistent results. We, therefore, performed a meta-analysis to clarify this issue METHODS:: Various databases were conducted up to November 21, 2018. All randomized controlled trials and cohorts that compared Q-value-guided LASIK with standard LASIK were selected. Mean differences (MDs) or odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to evaluate the strength of the correlations. Additionally, different subgroup analyses and publication bias tests were performed. Data were extracted including the number of postoperative uncorrected visual acuity (UCVA) of 20/20 or better, postoperative UCVA, preoperative and postoperative Q-value, postoperative refractive spherical equivalent (SE), the number of postoperative SE within ±0.5D, higher order aberration (HOA), coma-like aberration and spherical-like aberration. RESULTS: A total of seventeen studies with 2640 patients and 3,358 eyes were included. It has been shown that postoperative Q-value (MD = -0.42; 95% CI: -0.64, -0.21; P < .001), HOA (MD = -0.14; 95% CI: -0.23, -0.06; P = .001), spherical-like aberration (MD = -0.19; 95% CI: -0.32, -0.06; P = .004) rather than postoperative UCVA (MD = 0.04; 95% CI: 0.01, 0.07; P = .012) were significantly better in the Q-value-guided LASIK than standard LASIK. However, the pooled results revealed that no significant differences were found between the 2 paired groups of postoperative UCVA of 20/20 or better (OR = 1.09; 95% CI: 0.62, 1.92; P = .763), preoperative Q-value (MD = -0.00; 95% CI: -0.02, 0.02; P = .922), postoperative refractive SE (MD = 0.08; 95% CI: -0.09, 0.25; P = .336), coma-like aberration (horizontal: MD = -0.00; 95% CI: -0.03, 0.03; P = .966; vertical: MD = -0.01; 95% CI: -0.03, 0.01; P = .263) and postoperative SE within ±0.5 D (OR = 1.06; 95% CI: 0.48, 2.33; P = .886). Likewise, similar results were detected in some corresponding subgroups. CONCLUSION: Q-value-guided LASIK is a safe, effective and predictable surgical option for treating myopia, especially showing superiority over standard LASIK in postoperative Q-value, HOA and spherical-like aberration. However, more detailed studies are required to confirm our conclusions in advanced researches.


Assuntos
Ceratomileuse Assistida por Excimer Laser In Situ/métodos , Miopia/cirurgia , Humanos , Testes Visuais , Acuidade Visual
11.
Arch. Soc. Esp. Oftalmol ; 95(11): 544-549, nov. 2020. tab, ilus, graf
Artigo em Espanhol | IBECS | ID: ibc-197745

RESUMO

OBJETIVO: Comparar el grosor epitelial corneal (GEC) en pacientes intervenidos de LASIK miópico de más de un año respecto a sujetos no operados. MÉTODOS: En este estudio retrospectivo observacional se incluyeron 93 sujetos no operados (186 ojos) y 26 sujetos (52 ojos) operados de LASIK miópico. Se realizó una tomografía óptica de segmento anterior (OCT-SA) combinada con anillo de Plácido en todos los sujetos y se midió el GEC por sectores. Se hizo análisis estadístico para determinar diferencias entre las variables medidas en ambos grupos, así como análisis multivariante para buscar predictores de GEC. RESULTADOS: No hubo diferencias significativas entre los grupos en términos demográficos (edad, sexo) ni de segmento anterior (equivalente esférico, paquimetría) (todas las p > 0,05). Se obtuvieron diferencias estadísticamente significativas (p < 0,05) entre los dos grupos en todos los sectores estudiados, central, anillos interno y externo, siendo mayores todos los valores de GEC en los pacientes intervenidos de LASIK ≥ 1 año. A excepción del tiempo transcurrido desde la cirugía (p = 0,00), no se encontró correlación entre el GEC y la edad, el sexo, las dioptrías ablacionadas ni otra variable estudiada (p > 0,05). CONCLUSIONES: El GEC medio y por sectores medido mediante la OCT-SA es mayor en pacientes intervenidos de LASIK hace más de un año. La única variable correlacionada con el GEC tras el LASIK es el tiempo desde la cirugía. Las modificaciones del GEC deben ser tenidas en cuenta al planear la cirugía refractiva por sus implicaciones en el resultado final


OBJECTIVE: To compare corneal epithelial thickness (CET) between patients who underwent LASIK surgery for the correction of myopia at least one year ago and healthy subjects. METHODS: A retrospective observational study was conducted that included 93 healthy subjects (186 eyes) and 26 subjects (52 eyes) that underwent myopic LASIK surgery. OCT-SA, combined with Placido disk, was performed on all subjects, and CET maps were measured. Statistical analysis was performed to analyse differences between groups. Multivariate analysis was also performed to look for possible predictors of final CET. RESULTS: There was no statistically significant differences between the groups in the demographic (age, sex) or anterior segment parameters (spherical equivalent, pachymetry) (all P > .05). Statistically significant differences (P < .05) were obtained between both groups when comparing CET, including central, internal, and external rings (higher in patients that underwent LASIK surgery ≥1 year). With the exception of the time elapsed since surgery (P = .00), no correlation was found between the CET and age, sex, ablated dioptres, or other variables studied (P < .05). CONCLUSIONS: CET values measured by the OCT-SA were higher in patients that underwent LASIK surgery ≥ 1 year. The only variable that correlated with the CET after LASIK was the time elapsed since surgery. CET changes should be taken into consideration when planning refractive surgery due to its implications on the final outcome


Assuntos
Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Paquimetria Corneana/métodos , Ceratomileuse Assistida por Excimer Laser In Situ/métodos , Tomografia de Coerência Óptica/métodos , Estudos Retrospectivos , Estudos de Casos e Controles , Resultado do Tratamento , Valores de Referência , Análise de Variância , Acuidade Visual , Córnea/patologia
12.
Vestn Oftalmol ; 136(5): 32-38, 2020.
Artigo em Russo | MEDLINE | ID: mdl-33056961

RESUMO

Modern tonometers (Ocular Response Analyzer) can only show the presence of biomechanical disorders of the fibrous membrane, while elastotonometry reacts not only to their presence, but also to their type. PURPOSE: To build a mathematical model that would use elastotonometry to assess biomechanical properties of the eye in treatment of hyperopia with LASIK and FemtoLASIK surgeries. MATERIAL AND METHODS: The study included 64 operations: 34 FemtoLASIK surgeries, and 31 LASIK surgeries. All patients before and after surgery underwent standard examination necessary for keratorefractive surgery, including elastotonometry. The next step was the analysis of elastotonometry curves and eye finite element model in the software package Ansys (Ansys, Inc.; U.S.A.). During the analysis, the fibrous membrane was modeled by two spherical segments, which before elastotonometry were influenced only by true intraocular pressure (IOP). There was a problem of determining tonometric IOP when the cornea is pressured with flat bottomed loads during elastotonometry. It was taken into account that at the first stage of loading, the IOP was applied, and then the force corresponding to the weight of the tonometer. After tonometry, IOP increased so that the volume inside the composite membrane corresponded to the value before loading. RESULTS: Mathematical modeling has shown that after surgical treatment of hyperopia, flexural stiffness of the cornea decreases, elevation of the elastotonometry curve increases, and the higher the true IOP, the greater the elevation. The greatest increase in lift due to increased IOP is observed after LASIK operation, while after FemtoLASIK this change is not significant, in which case the dependence of tonometric IOP on the weight of the load is almost linear. CONCLUSION: The obtained results allow for elastotonometry to be recommend for further medical research as a promising method for assessing biomechanical characteristics of the fibrous membrane of the eye.


Assuntos
Hiperopia , Ceratomileuse Assistida por Excimer Laser In Situ , Córnea/cirurgia , Humanos , Hiperopia/diagnóstico , Hiperopia/etiologia , Hiperopia/cirurgia , Pressão Intraocular , Ceratomileuse Assistida por Excimer Laser In Situ/efeitos adversos , Tonometria Ocular
14.
PLoS One ; 15(9): e0238399, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32915816

RESUMO

PURPOSE: To analyze the influence of the final spherical equivalent (SE) in LogMAR uncorrected distance visual acuity (UDVA) one year after refractive surgery. We analysed refractive results, their predictability and efficacy, and the safety results of the different methods as secondary outcomes. SETTING: Refractive Surgery Unit of the Institut Català de Retina (ICR) in Barcelona, Spain. DESIGN: Retrospective, analytical observational study. METHODS: Retrospective and observational study of 654 eyes of 327 patients who underwent refractive surgery to treat their myopia or myopic astigmatism using LASIK, FS-LASIK, PRK, PRK Xtra or ICL-type lens implantation surgery were included. RESULTS: The correlation between the SE in absolute value was statistically significant in all techniques utilized, reaching higher values in the FS-LASIK and LASIK techniques, 0.774 and 0.706 respectively, and lesser values in PRK (0.480) and PRK Xtra (0.482). A significant adjustment via a univariate linear regression model could be implemented in all techniques, albeit the R2 coefficient of determination values were higher than those for the FS-LASIK (0.599) and LASIK (0.494) techniques. CONCLUSIONS: There is a positive correlation between post-surgical SE value and post-operative LogMAR UDVA. These regression models can be adjusted to predict the final UDVA according to the final SE. The techniques that are most influenced by the final SE in terms of their visual results are FS-LASIK and LASIK.


Assuntos
Astigmatismo/cirurgia , Ceratomileuse Assistida por Excimer Laser In Situ/métodos , Implante de Lente Intraocular , Miopia/cirurgia , Ceratectomia Fotorrefrativa/métodos , Adulto , Astigmatismo/fisiopatologia , Feminino , Humanos , Ceratomileuse Assistida por Excimer Laser In Situ/efeitos adversos , Implante de Lente Intraocular/efeitos adversos , Lentes Intraoculares/efeitos adversos , Modelos Lineares , Masculino , Miopia/fisiopatologia , Ceratectomia Fotorrefrativa/efeitos adversos , Estudos Retrospectivos , Espanha , Resultado do Tratamento , Acuidade Visual , Adulto Jovem
15.
PLoS One ; 15(8): e0237990, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32841281

RESUMO

PURPOSE: To 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). DESIGN: Retrospective, Comparative, Observational study. SETTING: Department of Medicine and Surgery, University of Salerno, Italy. METHODS: Ninety 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. RESULTS: In 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 <0.5D, and 53 eyes (77.94%) reported a refractive error <1D, For ALxK method, 32 eyes (47.06%) reported a refractive error <0.5 D, and 53 eyes (77.94%) reported a refractive error <1 D. ALMA method, reported a MedAE of 0.55 D, and an higher number of patients with a refractive error <0.5 D (35 eyes, 51.47%), and with a refractive error <1 D (54 eyes, 79.41%). CONCLUSIONS: Based 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.


Assuntos
Ceratomileuse Assistida por Excimer Laser In Situ , Lentes Intraoculares , Ceratectomia Fotorrefrativa , Feminino , Humanos , Masculino , Período Pré-Operatório , Estudos Retrospectivos
16.
Vestn Oftalmol ; 136(4): 110-116, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32779464

RESUMO

PURPOSE: To analyze the effectiveness of artificial tear drops Thealoz (trehalose 3%) in the correction of dry eye syndrome (DES) after ReLEx SMILE and FEMTO LASIK keratorefractive surgeries. MATERIAL AND METHODS: The study included 20 patients (40 eyes) who underwent a keratorefractive surgery and were prescribed instillations of Thealoz artificial tear drops for the correction of dry eye syndrome. Patients were divided into 2 group: the 1st group consisted of 10 patients who underwent ReLEx SMILE surgery, the 2nd group - 10 patients after FEMTO LASIK. The effectiveness of the treatment was evaluated at 1 and 3 months after the surgery using Ocular Surface Disease Index (OSDI), changes in the anterior corneal epithelium (Oxford scale), and tear break-up time (Norn's test). RESULTS: It was found that the use of artificial tear drops Thealoz regardless of the type of keratorefractive surgery helps reduce discomfort based on the OSDI questionnaire from 10.90±4.55 to 10.20±4.07 and 8.89±3.26 points by 1 and 3 months of the follow-up, respectively (p≤0.05). The degree of epitheliopathy according to the Oxford scale decreases from 0.73±0.75 to 0.25±0.43 points 3 months after the surgery (p≤0.05), which is accompanied by a significant increase in tear break-up time (Norn's test) from 11.18±1.19 to 12.43±1.03 and 12.45±1.03 seconds 1 and 3 months after treatment, respectively (p≤0,05). CONCLUSION: Complex evaluation of the ocular surface has proved that artificial tear drops Thealoz is effective in reducing DES manifestations after keratorefractive surgery. The results clearly demonstrate that the drug helps increase stability of the tear break-up time, as well as contributes to the decrease in epitheliopathy and subjective discomfort sensations, giving grounds to widen its use in clinical practice.


Assuntos
Síndromes do Olho Seco , Ceratomileuse Assistida por Excimer Laser In Situ , Miopia/cirurgia , Humanos , Lágrimas , Trealose
17.
Ophthalmology ; 127(11): e100, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32739178
19.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 37(4): 608-613, 2020 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-32840077

RESUMO

The decrease of corneal stiffness is the key factor leading to keratoconus, and the corneal collagen fiber stiffness and fiber dispersion are closely related to the corneal biomechanical properties. In this paper, a finite element model of human cornea based on corneal microstructure, namely collagen fiber, was established before and after laser assisted in situ keratomileusis (LASIK). By simulating the Corvis ST process and comparing with the actual clinical results, the hyperelastic constitutive parameters and corneal collagen fiber stiffness modulus of the corneal material were determined before and after refractive surgery. After LASIK, the corneal collagen fiber stiffness modulus increased significantly, and was highly correlated with central corneal thickness (CCT). The predictive relationship between the corneal collagen fiber stiffness modulus and the corresponding CCT before and after surgery was: k 1 before = exp(9.14 - 0.009CCT before), k 1 after = exp(8.82 - 0.008CCT after). According to the results of this study, the central corneal thickness of the patient can be used to estimate the preoperative and postoperative collagen fiber stiffness modulus, and then a personalized corneal model that is more consistent with the actual situation of the patient can be established, providing a theoretical reference for more accurately predicting the safe surgical cutting amount of the cornea.


Assuntos
Córnea , Fenômenos Biomecânicos , Topografia da Córnea , Análise de Elementos Finitos , Humanos , Ceratomileuse Assistida por Excimer Laser In Situ , Miopia
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