Resultados motores en cirugía fotoablativa en pacientes miopes / Motor Outcomes of Photoablative Surgery in Myopic Patients

Objetivo: Determinar los resultados motores post cirugía refractiva corneal con láser de excímero en pacientes miopes con o sin astigmatismo asociado. Método: Se realizó un estudio preexperimental del tipo antes y después, en el que fueron incluidos 81 pacientes (162 ojos) tratados con LASEK-MMC (65 pacientes) o PRK-MMC (16 pacientes) seguidos por tres meses. Se les realizó un examen oftalmológico completo y se evaluaron las siguientes variables: punto próximo de convergencia, la amplitud de convergencia, divergencia y el alineamiento ocular precirugía y poscirugía. Resultados: Con la cirugía se observó un incremento significativo del punto próximo de convergencia (LASEK-MMC: p = 0,000 y PRK-MMC: p = 0,021). La amplitud de convergencia de cerca y de lejos, así como la amplitud de divergencia tendieron a disminuir, pero la diferencia no fue significativa (p > 0,05). Aumentó el porcentaje de pacientes con exodesviaciones de cerca, después de la cirugía LASEK-MMC (26,2 por ciento → 60,0 por ciento, p = 0,000) y de la PRK-MMC (18,8 por ciento → 81,3 por ciento, p = 0,000), y predominaron las heteroforias pequeñas en ambos casos (LASEK-MMC: 52,3 por ciento y PRK-MMC: 75,0 por ciento). Conclusiones: Con la cirugía fotoablativa con láser, aumentaron las exodesviaciones en el posoperatorio, pero se trató fundamentalmente de heteroforias pequeñas, aunque un número reducido de pacientes desarrolló nuevas exodesviaciones(AU)

Objective: To determine the eye movement outcomes after excimer laser corneal refractive surgery in myopic patients with or without associated astigmatism. Methods: A preexperimental, before-and-after study was carried out with 81 patients (162 eyes) treated with laser-assisted subepithelial keratectomy (LASEK) (65 patients) or photorefractive keratectomy (PRK) (16), with intraoperative application of mitomycin-C (MMC) in both cases, and followed for three months. A complete ophthalmologic examination was performed and the following variables were evaluated before and after the surgery: near convergence point, convergence amplitude, divergence and ocular alignment. Results: With surgery, a significant increase in the near point of convergence was observed (LASEK-MMC: P=0.000; PRK-MMC: P=0.021). The near and far convergence amplitude tended to decrease, but the difference was not significant (P > 0.05). The percentage of patients with near exodeviations increased after LASEK-MMC (26.2 percent → 60.0 percent, P=0.000) and PRK-MMC (18.8 percent → 81.3 percent, P=0.000), while small heterophorias predominated in both cases (LASEK-MMC: 52.3 percent and PRK-MMC: 75.0 percent). Conclusions: With laser photoablative surgery, exodeviations increased after surgery, but these were primarily small heterophorias, although a small number of patients developed new exodeviations(AU)

Resultados refractivos y visuales en cirugía fotoablativa en pacientes miopes / Refractive and visual results in photoablative surgery in myope patients

Objetivo: Evaluar los resultados refractivos y visuales post cirugía refractiva corneal con láser de excímero (LASEK-MMC o PRK-MMC) en pacientes miopes con o sin astigmatismo asociado. Método: Se realizó un estudio preexperimental del tipo antes y después, en el que fueron incluidos 81 pacientes (162 ojos) tratados con LASEK-MMC (65 pacientes) o PRK-MMC (16 pacientes) seguidos por tres meses. Se les realizó un examen oftalmológico completo y se evaluaron las variables: edad, sexo, diagnóstico y tipo de miopía, así como agudeza visual, esfera, cilindro, equivalente esférico precirugía y poscirugía. Además, se analizó la función visual y los resultados de la refracción. Resultados: El valor de la mediana de edad fue de 24,0 años en los pacientes tratados con LASEK-MMC y en el grupo con PRK-MMC fue de 23,0 años. En ambos grupos existió un predominio del sexo femenino. La totalidad de los pacientes tratados presentaba un astigmatismo miópico compuesto con niveles de miopía leve. A los tres meses el 96,9 por ciento de los pacientes tratados con LASEK-MMC y el 93,8 por ciento de los tratados con PRK-MMC tenían una agudeza visual no corregida de 20/20 o más y todos tenían una visión de 20/40 o más. Conclusiones: La cirugía fotoablativa con láser tiene buenos resultados refractivos y visuales ya que la mayoría de los pacientes quedaron emétropes con una marcada mejoría de la agudeza visual sin corrección y de la refracción en el posoperatorio(AU)

Objective: To evaluate refractive and visual outcomes after excimer laser corneal refractive surgery (laser-assisted subepithelial keratectomy [LASEK] or photorefractive keratectomy [PRK], with intraoperative application of mitomycin-C [MMC]) in myopic patients with or without associated astigmatism. Methods: A preexperimental, before-and-after study was carried out with 81 patients (162 eyes) treated with LASEK-MMC (65 patients) or PRK-MMC (16 patients) and followed for three months. A complete ophthalmologic examination was done and the following variables age, sex, diagnosis and type of myopia were assessed, as well as pre-surgery and post-surgery visual acuity, sphere, cylinder and spherical equivalent. In addition, visual function and the refraction results were analyzed. Results: The median age was 24.0 years in the LASEK-MMC group and 23.0 years in the PRK-MMC group. In both groups there was a predominance of the female sex. All treated patients had compound myopic astigmatism with mild myopia. At three months, 96.9 percent of patients treated with LASEK-MMC and 93.8 percent of patients treated with PRK-MMC had uncorrected visual acuity of 20/20 or better, and all had vision of 20/40 or better. Conclusions: Laser photoablative surgery has good refractive and visual outcomes as most patients became emmetropic with marked improvement in uncorrected visual acuity and refraction postoperatively(AU)

Resultados refractivos y visuales en pacientes operados de miopía con técnicas de superficies / Refractive and visual results in patients operated on for myopia with surface techniques

Objetivo: Comparar los resultados visuales y refractivos pre- y posoperatorios en pacientes miopes operados con técnicas de superficie y perfil de ablación asférico. Métodos: Se realizó un estudio experimental controlado aleatorizado abierto, tipo de equivalencia y no inferioridad, en 160 pacientes (320 ojos). En el estudio se formaron dos grupos: el primero quedó constituido por 80 pacientes (160 ojos), a quienes se les realizó queratectomía fotorrefractiva más mitomicina C, y el segundo fue conformado por 80 pacientes (160 ojos), a quienes se les realizó LASEK más mitomicina C. Resultados: Predominaron en ambos grupos las mujeres con miopía leve y edades entre 21 y 29 años. A los tres meses el grupo queratectomía fotorrefractiva más mitomicina C tenía agudeza visual sin corrección de 0,97 ± 0,09; esfera 0,003 ± 0,21; cilindro -0,09 ± 0,30 y equivalente esférico -0,04 ± 0,23. En el grupo LASEK más mitomicina C, la agudeza visual sin corrección fue de 0,96 ± 0,11; la esfera -0,007 ± 0,24; el cilindro -0,08 ± 0,25 y el equivalente esférico -0,06 ± 0,26. Conclusión: Ambas técnicas quirúrgicas mejoraron significativamente los resultados refractivos y visuales, pero no hubo diferencia entre ellas(AU)

Objective: Compare the pre- and postoperative visual and refractive results in myopic patients operated with surface techniques and aspheric ablation profile. Methods: An open randomized controlled experimental study, equivalence and non-inferiority type was carried out in 160 patients (320 eyes). In the study, two groups were formed: the first group was made up of 80 patients (160 eyes), who underwent Photorefractive keratectomy - mitomycin C, and the second group made up of 80 patients (160 eyes), underwent LASEK - mitomycin C. Results: Women with mild myopia and ages between 21 and 29 years old predominated in both groups. At three months, the Photorefractive keratectomy - mitomycin C group had AVSC 0.97 ± 0.09; sphere 0.003 ± 0.21; cylinder -0.09 ± 0.30 and spherical equivalent -0.04 ± 0, 2. 3. In the Photorefractive keratectomy - mitomycin C group, AVSC 0.96 ± 0.11; sphere -0.007 ± 0.24; cylinder -0.08 ± 0.25 and spherical equivalent -0.06 ± 0.26. Conclusion: Both surgical techniques improved significantly refractive and visual results, but there was no difference between them(AU)

Diferentes concentraciones de mitomicina C en la prevención del haze en la queratectomía fotorrefractiva / Different concentrations of mitomycin C for haze prevention in photorefractive keratectomy

Objetivo: Evaluar la utilidad de dos concentraciones de mitomicina C para la prevención del haze en la queratectomía fotorrefractiva. Métodos: Se realizó un estudio experimental aleatorizado en 26 ojos de 17 pacientes con defectos miópicos. Los pacientes fueron asignados a dos grupos según las dosis de mitomicina C (0,02 por ciento grupo 1 y 0,002 por ciento grupo 2). La variable de respuesta principal fue la presencia de haze. Se buscó correlación entre la magnitud del haze con grado de ametropía tratada, profundidad de ablación, microscopia endotelial y resultados visuales y refractivos. Resultados: A los 6 meses la mayoría de los pacientes del grupo 1 no presentó haze (ocho ojos / 57 por ciento), y del grupo 2 mantuvieron haze 0,5 (6 ojos / 50 por ciento). En la ametropía severa el haze en el grupo 2 fue mayor que en el grupo 1 durante todo el posoperatorio, y se observó la mayor diferencia al sexto mes con 0,5 ± 0,4 vs. 1,5 ± 0,32. En ablaciones > 75 micras el grupo dos terminó con más haze que el uno, con 0,5 ± 0,44 vs. 1,75 ± 0,76. La agudeza visual sin corrección se vio más afectada en el grupo 2. No hubo daño endotelial en ningún grupo. Conclusión: La presencia de haze predomina en los casos tratados con dosis 0,002 por ciento de mitomicina C, comparada con la dosis 0,02 por ciento, aunque en este caso ambos grupos mantuvieron un resultado visual y refractivo adecuado y baja toxicidad endotelial.

Objective: Evaluate the usefulness of two concentrations of mitomycin C for haze prevention in photorefractive keratectomy. Methods: An experimental randomized study was conducted of 26 eyes of 17 patients with myopic defects. The patients were divided into two groups according to their mitomycin C doses (Group 1: 0.02 percent and Group 2: 0.002 percent). The main response variable was the presence of haze. Verification was performed of the correlation between haze magnitude and the degree of the ametropia treated, ablation depth, endothelial microscopy, and visual and refractive results. Results: At six months most patients in Group 1 did not have any haze (eight eyes / 57 percent), whereas 0.5 (6 eyes / 50 percent) in Group 2 still had haze. In severe ametropia, haze was larger in Group 2 than in Group 1 throughout the postoperative period, the greatest difference being observed in the sixth month with 0.5 ± 0.4 vs 1.5 ± 0.32. In ablations > 75 microns, Group 2 ended with more haze than Group 1, with 0.5 ± 0.44 vs 1.75 ± 0.76. Uncorrected visual acuity was more affected in Group 2. No endothelial damage occurred in either group. Conclusion: The presence of haze prevails in cases treated with 0.002 percent doses of mitomycin C, as compared with 0.02 percent doses, though in this case both groups maintained an appropriate visual and refractive result and low endothelial toxicity(AU)

Treatment strategy for bilateral severe subepithelial fibrosis after photorefractive keratectomy enhancement / Estratégia de tratamento para fibrose subepitelial grave bilateral após aprimoramento com ceratectomia fotorrefrativa

ABSTRACT A 27-year-old healthy man with a history of bilateral photorefractive keratectomy (PRK) enhancement after femtosecond laser in situ keratomileusis (LASIK) presented with decreased uncorrected distance visual acuity (UDVA) of 20/125 in the right eye (OD) and 20/300 in the left eye (OS) six months after PRK. Examination revealed bilateral dense subepithelial opacities. Both eyes (OU) were treated with superficial keratectomy combined with phototherapeutic keratectomy (PTK) and adjunctive application of mitomycin C 0.02%. At three months follow up UDVA was 20/30 OD and 20/25 OS. Superficial keratectomy combined with PTK seems to be a safe and efficient technique for treatment of dense subepithelial scar formation following PRK enhancement after LASIK.

RESUMO Um homem saudável de 27 anos de idade com história de aprimoramento com ceratectomia fotorrefrativa (PRK) bilateral, após Ceratomileuse Assistida por Excimer Laser In Situ (LASIK) com laser de femtossegundos, apresentou diminuição da acuidade visual à distância não corrigida (AVNC) de 20/125 no olho direito (OD) e 20/300 no olho esquerdo (OE) seis meses após PRK. O exame revelou opacidades subepiteliais densas bilaterais. Ambos os olhos (AO) foram tratados com queratectomia superficial combinada com ceratectomia fototerapêutica (PTK) e aplicação adjuvante de mitomicina C a 0,02%. Aos três meses de acompanhamento, o AVNC foi de 20/30 OD e 20/25 OE. A ceratectomia superficial combinada com PTK parece ser uma técnica segura e eficiente para o tratamento da formação densa de cicatrizes subepiteliais após o aprimoramento com PRK pós-LASIK.

Laser topoguiado como tratamento de ectasia pós lasik / Topoguided laser as treatment of ectasia after lasik

RESUMO O laser in situ keratomileusis (LASIK) é o método cirúrgico refrativo mais realizado no mundo com excelentes resultados, porém tal método não é isento de riscos. A ectasia pós LASIK é uma complicação grave e se caracteriza por um aumento progressivo da curvatura e afinamento da córnea, resultando em astigmatismo irregular e diminuição da acuidade visual. Sua incidência na literatura atual é de aproximadamente 0,033%. O principal tratamento dessa complicação é o implante de anel intra-estromal com cross-linking. Neste artigo descrevemos um caso de uma mulher de 45 anos submetida a sucessivas tentativas de tratamento de ectasia pós LASIK, com implante de anel intra-estromal bilateral, sem sucesso em um dos olhos. Foi feito o uso do excimer laser topoguiado através do photorefractive keratectomy (PRK) sem o cross-linking, que optamos por não realizar pela estabilidade há anos, pelo risco alto de haze e pela ablação apenas na lamela (que era espessa).A paciente obteve melhorasignificativa da visão e da qualidade de vida. Mantemos o acompanhamento a cada seis meses desde então com a tomografia da córnea.

ABSTRACT The laser in situ keratomileusis (LASIK) is the most widely used refractory surgical method in the world with excellent results, but this method is not without risks. Post-LASIK ectasia is a serious complication and is characterized by a progressive increase in curvature and thinning of the cornea, resulting in irregular astigmatism and decreasing visual acuity. Its incidence in the current literature is approximately 0.033%. The main treatment for this complication is the implantation of an intra-stromal ring with crosslinking. In this article, we describe a case of a 45-year-old woman who underwent successive attempts to treat post-LASIK ectasia, with bilateral intra-stromal ring implantation, with no success in the eyes. Excimer laser was used, made through photorefractive keratectomy (PRK) without cross-linking and the patient obtained significant improvement in vision and in quality of life.

Codeine plus acetaminophen improve sleep quality, daily activity level, and food intake in the early postoperative period after photorefractive keratectomy: a secondary analysis / Melhora da qualidade do sono e das atividades diárias pós PRK imediato utilizando codeína com paracetamol: análise secundária de um ensaio clínico randomizado, duplo-cego e placebo-controlado

ABSTRACT Purpose: To determine whether codeine plus acetaminophen after photorefractive keratectomy (PRK) have beneficial effects on sleep quality, activity levels, and food intake, beyond their effect of pain relief. Methods: We enrolled 40 patients (80 eyes) in this randomized, double-blind, paired-eye, placebo-controlled, add-on trial. Each eye was treated 2 weeks apart, and the patients were randomly allocated to receive either the placebo or the intervention (30 mg codeine and 500 mg acetaminophen) (4 times a day for 4 days). Outcomes were sleep quality, daily activity level, and food intake within 24-72 h post-photorefractive keratectomy, as measured by the McGill Pain Questionnaire. Results: Sleep quality and daily activity level were inversely associated with pain scores within the first 48 h post-photorefractive keratectomy. During the intervention, patients were significantly more likely to score their sleep quality as good at 24 h (relative risk=2.5; 95% confidence interval 1.48-4.21, p<0.001) and 48 h compared to during placebo (relative risk=1.37; 95% confidence interval: 1.03-1.84, p=0.023). The probability of reporting good daily activity level at 24 and 72 hours post-photorefractive keratectomy was three times higher when patients received the intervention compared to the placebo (relative risk=3.0; 95% confidence interval: 1.49-6.15, p=0.006 and relative risk=1.31; 95% confidence interval: 1.02-1.67, p=0.021, respectively). No difference was observed in food intake. Conclusion: The oral combination of codeine and acetaminophen significantly improves sleep quality and daily activity level within the first 24-72 h post-photorefractive keratectomy compared to a placebo.

RESUMO Objetivo: Determinar se codeína (30 mg) mais pa­racetamol (500 mg) após ceratectomia fotorrefrativa fornece efeitos benéficos sobre a qualidade do sono, níveis de atividade e ingestão de alimentos além de seu efeito analgésico. Métodos: Quarenta pacientes (80 olhos) foram incluídos neste estudo randomizado, duplo-cego, pareado, placebo-controlado, add-on. Cada olho foi tratado com 2 semanas de intervalo, sendo aleatoriamente alocado para placebo ou intervenção (4x/dia durante 4 dias). Os resultados incluíram a qualidade do sono, atividade diária e ingestão de alimentos dentro de 24-72 horas de pós-operatório, conforme medido pelo McGill Pain Questionnaire. Resultados: A qualidade do sono e os níveis de atividade foram inversamente associados aos escores de dor nas primeiras 48 horas após o ceratectomia fotorrefrativa. Durante a intervenção, os pacientes foram significativamente mais propensos a classificar seu sono como bom em 24 horas (risco relativo=2,5, intervalo de confiança de 95%: 1,48-4,21, p<0,001) e 48 horas comparado ao placebo (risco relativo=1,37, intervalo de confiança de 95%: 1,03-1,84, p=0,023). A probabilidade de relatar bons níveis de atividade em 24 e 72 horas após ceratectomia fotorrefrativa também foi significativamente maior durante a intervenção em comparação com placebo (risco relativo=3,0, intervalo de confiança de 95%: 1,49-6,15, p=0,006 e risco relativo=1,31, intervalo de confiança de 95%: 1,02 -1,67, p=0,021, respectivamente). Nenhuma diferença foi observada entre a intervenção e placebo em relação à alimentação oral. Conclusão: A combinação de codeína e paracetamol melhorou significativamente a qualidade do sono e atividades diárias nas primeiras 24-72 horas após o ceratectomia fotorrefrativa em comparação com placebo.

Laser topoguiado como redutor de aberrações ópticas pós ceratotomia radial e LIO multifocal / Topoguided laser as a reducer of optical aberrations after radial keratotomy and multifocal LIO

Resumo A cirurgia de catarata com implante de lente intra-ocular é uma das cirurgias mais realizadas no mundo e, atualmente, os pacientes que se submetem a essa cirurgia podem utilizar o implante com lente intraocular (LIO) multifocal como alternativa ao uso de óculos. Um grande desafio para o cirurgião são os pacientes já submetidos previamente a ceratotomia radial (RK), pois além de terem um cálculo biométrico mais desafiador, apresentam importantes aberrações ópticas corneanas, sendo uma contra-indicação para o uso de lentes multifocais para a maioria dos oftalmologistas. Neste artigo, relatamos o caso de uma paciente que foi submetida, na juventude, a uma RK e passou a referir importante incômodo visual após a correção de catarata com facectomia e implante de LIO multifocal. Esta paciente foi submetida a uma ceratectomia fotorrefrativa (PRK) para diminuir as irregularidades da córnea com boa evolução clínica e resultado visual satisfatório. Esse caso chama a atenção para a alternativa do excimer laser topoguiado em casos semelhantes e alerta para o risco do uso desse tipo de lente em córneas irregulares.

Abstract Cataract surgery with intraocular lens implantation is one of the most commonly performed surgeries in the world and, currently, patients who undergo this surgery can use the multifocal intraocular lens (IOL) implant as an alternative to wearing glasses. A great challenge for the surgeon are patients who have previously undergone radial keratotomy (RK), because in addition to having a more challenging biometric calculation, they also have important corneal optical aberrations, being a contraindication for the use of multifocal lenses for most patients. ophthalmologists. In this article, we report the case of a patient who underwent a RK in her youth and started to report an important visual discomfort after cataract correction with facectomy and multifocal IOL implantation. This patient underwent a photorefractive keratectomy (PRK) to reduce corneal irregularities with good clinical evolution and satisfactory visual result. This case draws attention to the alternative of topography-guided laser excimer in similar cases and warns of the risk of using this type of lens in irregular corneas.

LASEK-mitomicina C versus PRK-mitomicina C en pacientes con miopía o astigmatismo miópico compuesto / LASEK-mitomycin C versus PRK-mitomycin C in patients with myopia or compound myopic astigmatism

RESUMEN Objetivo: Evaluar los resultados relacionados con la efectividad y la seguridad en el tratamiento con queratectomía subepitelial asistida por láser con mitomicina C versus queratectomía fotorreactiva con mitomicina C en ojos con miopía o astigmatismo miópico compuesto. Métodos: Se realizó un estudio experimental, longitudinal y prospectivo en el Instituto Cubano de Oftalmología Ramón Pando Ferrer entre abril del año 2016 y abril de 2017. Se empleó un muestreo aleatorio simple por el cual se obtuvo la técnica quirúrgica a realizar. El primer ojo operado fue el derecho y a la semana se realizó la cirugía en el ojo izquierdo, en el cual se aplicó la otra técnica quirúrgica. Esto permitió realizar en cada paciente ambas técnicas quirúrgicas. La muestra quedó constituida por 146 ojos (73 pacientes) que cumplían con los criterios de selección. Resultados: El comportamiento preoperatorio entre los dos grupos fue muy similar. En ninguno de los casos existieron diferencias en las variables que se evaluaron (agudeza visual sin corrección, agudeza visual mejor corregida, esfera, cilindro y equivalente esférico). La diferencia entre los valores preoperatorios y los encontrados a los 6 meses del tratamiento quirúrgico en cada grupo fueron estadísticamente significativos (p= 0,000) para todas las variables analizadas, excepto para la agudeza visual mejor corregida en el grupo de ojos tratados con láser con mitomicina C (p= 0,083). El haze y el defecto de epitelización fueron los dos tipos de complicaciones observadas. Conclusiones: Se demostró que ambas técnicas quirúrgicas son efectivas y seguras(AU)

ABSTRACT Objective: Evaluate the effectiveness and safety of laser-assisted subepithelial keratectomy with mitomycin C vs. photoreactive keratectomy with mitomycin C in eyes with myopia or compound myopic astigmatism. Methods: An experimental prospective longitudinal study was conducted at Ramón Pando Ferrer Cuban Institute of Ophthalmology from April 2016 to April 2017. Simple random sampling was used to decide on the surgical technique to be applied. Surgery was first performed on the right eye using one of the techniques, and then one week later on the left eye with the other technique. That way each patient could undergo both surgical techniques. The sample was composed of 146 eyes (73 patients) meeting the inclusion criteria. Results: Preoperative behavior was very similar in the two groups. In neither case were differences found in the variables analyzed (uncorrected visual acuity, best corrected visual acuity, sphere, cylinder and spherical equivalent). The differences between preoperative values and those found six months after surgery in each group were statistically significant for all the variables analyzed (p= 0.000), except for best corrected visual acuity in the group of eyes treated with laser with mitomycin C (p= 0.083). Haze and epithelization defect were the two types of complications observed. Conclusions: It was demonstrated that both surgical techniques are effective and safe(AU)

Comparison of Hyperopic Photorefractive Keratectomy and LASIK

PURPOSE: We compared the results of photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) for the correction of hyperopia. METHODS: Patients who underwent PRK or LASIK, under +6.00 diopters (D) hyperopia and under −2.00 D astigmatism were included. In total, 21 patients (38 eyes) underwent PRK surgery and 25 patients (41 eyes) underwent LASIK surgery. We compared the visual acuity, refractive error, safety, and efficacy between the two groups. RESULTS: The manifest refractive spherical equivalent (MRSE) of the PRK and LASIK groups at 1 and 3 months after surgery was significantly different between the two groups (p < 0.05). However, the MRSE was not significantly different at postoperative 6 and 12 months between the two groups. The uncorrected visual acuity (UCVA) of the PRK and LASIK groups at 1 month after surgery was significantly different between the two groups (p < 0.05). However, the UCVA was not significantly different at postoperative 3, 6, and 12 months between the two groups. The best-corrected visual acuity was not significantly different at postoperative 1, 3, 6, and 12 months between the two groups. The safety index was not significantly different between the two groups at postoperative 1, 3, 6, and 12 months. The efficacy index of the PRK group was lower than that of the LASIK group at 1 month after surgery. However, the efficacy index was not significantly different at postoperative 3, 6, and 12 months between the two groups. There was no statistically significant difference between the predictability of the two groups at postoperative 1 year. CONCLUSIONS: After PRK treatment, temporary myopic deviation was observed after 1 month, but there was no significant difference between the two treatments after 3 months of follow-up. In the correction of hyperopia, there was no significant difference between PRK and LASIK in efficacy or safety.

Effects of Cyclotorsion Orientation and Magnitude in Eyes with Compound Myopic Astigmatism on the Compensation Capacity of WaveLight EX500 Photorefractive Keratectomy

PURPOSE: To investigate the clinical effects of different orientation and magnitude of cyclotorsion on the compensation capacity of the WaveLight EX500 photorefractive keratectomy (PRK) platform. METHODS: This retrospective study comprised 400 eyes of 200 patients who underwent bilateral simultaneous PRK due to compound myopic astigmatism. The subjects were separated according to the orientation of cyclotorsion into incyclotorsion and excyclotorsion groups, and by the magnitude of cyclotorsion into group 1 (0.50 to 2.50 degrees), group 2 (3.00 to 5.00 degrees), group 3 (5.50 to 7.50 degrees), and group 4 (8.00 to 9.50 degrees). RESULTS: The mean magnitude of cyclotorsion was 3.50 ± 2.4 degrees (0.50 to 9.50 degrees) in the incyclotorsion group and 3.32 ± 2.3 degrees (0.50 to 9.50 degrees) in the excyclotorsion group (p = 0.617). The postoperative refractive outcomes of the incyclotorsion and excyclotorsion groups were similar (p > 0.05 for all). The postoperative mean cylindrical refractive error was −0.32 ± 0.3 diopters (D, −1.25 to 0.00 D) in group 1, −0.47 ± 0.2 D (−2.00 to 0.00 D) in group 2, −0.62 ± 0.2 D (−1.00 to −0.25 D) in group 3, and −0.91 ± 0.2 D (−1.50 to −0.50 D) in group 4 (p < 0.001). Preoperative cylindrical refractive error was positively correlated with magnitude of cyclotorsion (r = 0.125 and p = 0.013), which was also positively correlated with postoperative cylindrical refractive error (r = 0.600 and p < 0.001). CONCLUSIONS: Incyclotorsion and excyclotorsion can be equally compensable in the WaveLight EX500 PRK platform for compound myopic astigmatism. A value of ≤2.50 degrees cyclotorsion magnitude was observed to be more compensable than higher degrees of cyclotorsion magnitude. Preoperative high astigmatism was associated with high cyclotorsion magnitude, which was also associated with a high degree of postoperative astigmatism.

Focal phototherapeutic keratectomy for the treatment of apical leucoma syndrome / PTK focal para o tratamento da síndrome do leucoma apical

ABSTRACT The following report describes a case of apical leucoma syndrome after hyperopic photorefractive keratectomy following hyperopic laser in situ keratomileusis and the subsequent treatment of this complication with focal phototherapeutic keratectomy. The patient underwent focal transepithelial phototherapeutic keratectomy of 70 mm ablation and 1.5 mm diameter after pupil and ablation offset correction. After 1 year, significant improvement in vision was observed and only slight residual opacity remained on biomicroscopy and optical coherence tomography. Focal phototherapeutic keratectomy was effective and safe for the treatment of this complication.

RESUMO O relato a seguir descreve um caso da síndrome do Leucoma Apical após cirurgia ceratorrefrativa hipermetrópica depois de Laser hiperópico in situ keratomileusis, e o subsequente tratamento desta complicação com ceratectomia fototerapêutica focal. O paciente foi submetido à ceratectomia fototerapêutica focal transepitelial com ablação de 70 mm e diâmetro de 1,5 mm, após correção de offset pupilar. Depois de um ano, foi observada uma melhora significativa da acuidade visual permanecendo apenas leve opacidade residual na biomicroscopia e tomografia de coerência óptica. A ceratectomia fototerapêutica focal foi efetiva e segura para o tratamento desta complicação.

Corneal Power Determination with Corneal Tomography after Refractive Surgery with Excimer Laser / Determinación del poder corneal con un tomógrafo corneal luego de cirugía refractiva con láser excimer / Determinação da potência corneana com uma topografia de córnea após cirurgia refrativa com excimer láser

Introduction. Corneal power determination after refractive surgery with excimer laser is complex. Different alternatives with the use of corneal tomography have been used for this measurement. Objective. To evaluate various methods of determination of corneal power in patients undergoing photorefractive surgery, including diagnostic tests with quantitative measurements. Methodology. This is a retrospective observational study. We included patients undergoing photorefractive surgery with refractive results and post-operative corneal tomography taken at least ten weeks after surgery. Results. In myopic eyes, significant differences were found in the value determined by the keratometry derived from the clinical history when compared with the average post-operative manual keratometry, the simulated 32keratometry and the Mean Pupil Power of the Sirius®tomograph. On another note, when averaging the mean post-operative manual keratometry with the post-operative Mean Pupil Power (value called Kpopaverage 1) and comparing it with the keratometry derived from the clinical history method, no statistically significant differences were observed in myopic patients. Likewise, when averaging the simulated post-operative keratometry of the Sirius® equipment with the post-operative Mean Pupil Power (value called "Kpop average 2") and comparing it with the keratometry derived by the method of the clinical history, no statistically significant differences were observed in myopic patients. On the other hand, in hyperopic eyes and those with mixed astigmatism, mean errors from post-operative Mean Pupil Power, in comparison to the keratometry derived by clinical history method, were not significantly different from the errors when comparing the "Kpop average 1" and the "Kpop average 2"with keratometry derived by the clinical history method. Conclusions. In myopic eyes the post-operative corneal power determinations with the "Kpop average 1" and "Kpop average 2" are closer to the keratometry derived by clinical history method than to measurements from the average post-operative manual keratometry, the post-operative simulated keratometry or the Mean Pupil Power of the Sirius® equipment.

Introducción. La determinación del poder corneal, después de la cirugía refractiva con láser excimer, es difícil. Diferentes alternativas con el uso de tomógrafos corneales se han utilizado para esta medición. Objetivo. Evaluar diversos métodos de determinación del poder corneal en pacientes operados de cirugía fotorrefractiva, incluyendo pruebas diagnósticas con medidas cuantitativas. Metodología. Estudio retrospectivo de pacientes operados de cirugía fotorrefractiva que tuvieran resultados refractivos y tomografía corneal post-operatoria al menos diez semanas luego de cirugía. Resultados. En los ojos miopes se encontraron diferencias significativas en el valor determinado por la queratometría derivada de la historia clínica al compararla con la queratometría manual promedio postoperatoria, la queratometría simulada y el Mean Pupil Power del tomógrafo Sirius®. Por otra parte, al promediar la queratometría manual promedio postoperatoria con el Mean Pupil Power postoperatorio (valor denominado Kpop promedio 1) y compararla con la queratometría derivada por el método de la historia clínica, no se observaron en los pacientes miopes diferencias estadísticamente significativas. Asimismo, al promediar la queratometría simulada postoperatoria del equipo Sirius® con el Mean Pupil Power postoperatorio (valor denominado Kpop promedio 2) y compararla con la queratometría derivada por el método de la historia clínica tampoco se observaron en los pacientes miopes diferencias estadísticamente significativas. Por otro lado, en los ojos hipermétropes y con astigmatismo mixto, los promedios de los errores del Mean Pupil Power postoperatorio, con respecto a la queratometría derivada por el método de la historia clínica, no fueron significativamente diferentes de los errores al comparar la Kpop promedio 1 y la Kpop promedio 2 con la queratometría derivada por el método de la historia clínica. Conclusiones. En ojos miopes las determinaciones del poder corneal postoperatorio con las Kpop promedio 1 y Kpop promedio 2 se aproximan más a la queratometría derivada por el método de la historia clínica que a las mediciones de la queratometría manual promedio postoperatoria, la queratometría simulada postoperatoria o el Mean Pupil Power del equipo Sirius®. [Jaramillo LC, Galvis V, Tello A, Camacho PA, Castillo A, Pareja LA. Determinación del poder corneal con un tomógrafo corneal luego de cirugía refractiva con láser excimer. MedUNAB. 2018;21(1):16-30. doi:1029375/01237047.2397].

Introdução. A determinação da potência corneana, após a cirurgia refrativa com excimer láser, é difícil. Foram usadas diferentes alternativas com o uso de tomógrafos de córnea para esta medição. Objetivo. Avaliar vários métodos de determinação da potência corneana em pacientes submetidos à cirurgia fotorrefrativa, incluindo testes diagnósticos com medidas quantitativas. Métodos. Este é um estudo observacional retrospectivo. Foram incluídos pacientes submetidos à cirurgia fotorrefrativa com resultados refrativos e topografía corneana pós-operatória pelo menos um mês após a cirurgia. Resultados. Nos olhos míopes foram encontradas diferenças significativas no valor determinado pela ceratectomia derivada da história clínica, quando comparada com a média da ceratectomia manual pós-operátoria, a ceratectomia simulada e o Mean Pupil Power do tomógrafo Sirius®. Por outro lado, ao calcularmos a média da ceratectomia manual pós-operatória com o Mean Pupil Power pós-operatório (valor denominado Kpop média 1) e compará-la com a ceratectomia pelo método da história clínica, não foram observadas diferenças estatisticamente significantes nos pacientes miopes. Da mesma forma, ao calcular a média da ceratectomia pós-operatória simulada do equipamento Sirius® com o Mean Pupil Power pósoperatório (valor denominado Kpop média 2) e comparála com a ceratectomia derivada do método de história clínica, não foram observadas diferenças estatisticamente significantes nos pacientes miopes. Por outro lado, em olhos hipermetrópicos e com astigmatismo mixto, as médias de erros do Mean Pupil Power pós-operatório, em relação à ceratectomia derivada pelo método da história clínica, não foram significativamente diferentes dos erros na comparação do Kpop média 1 y la Kpop média 2 com a ceratectomia derivada pelo método da história clínica. Conclusões. Nos olhos míopes, as determinações de potência corneana pósoperatória com Kpop média 1 e Kpop média 2 estão mais próximas da ceratectomia derivada pelo método da história clínica do que das medidas de ceratectomia manual média pós-operatória, da ceratectomia simulada pós-operatória ou Mean Pupil Power do equipamento Sirius®. [Jaramillo LC, Galvis V, Tello A, Camacho PA, Castillo A, Pareja LA. Determinação da potência corneana com uma topografia de córnea após cirurgia refrativa com excimer láser. MedUNAB. 2018;21(1):16-30. doi:1029375/01237047.2397].

Degeneración marginal de Terrien / Terrien marginal degeneration

La degeneración corneal marginal de Terrien es una enfermedad ocular rara, generalmente bilateral y asimétrica, caracterizada por el adelgazamiento marginal de la córnea. Presentamos una paciente de 58 años quien asistió a consulta por lagrimeo y en la biomicroscopia mostraba adelgazamiento y opacidad marginal circunferencial en 360º con línea bien diferenciada de depósitos lipoideos y vascularización periférica nasal. En las imágenes de Scheimpflug se observó espesor corneal central conservado con adelgazamiento periférico. El mapa paquimétrico mostró valores inferiores en la zona nasal que correspondía con áreas de mayor valor queratométrico en el mapa de curvatura y con el área de mayor adelgazamiento por biomicroscopia. Por las características descritas se trata de una degeneración marginal de Terrien. Esta es una enfermedad de curso lento y progresivo, sin afectación de la córnea central, por lo que su pronóstico, en general, es bueno. Aquellos casos en los que se produce descemetocele o perforación periférica pueden necesitar una queratoplastia periférica lamelar penetrante(AU)

Terrien marginal corneal degeneration is a rare eye disease, generally bilateral and asymmetrical, which is characterized by marginal attenuation of the cornea. Here is a 58 years-old patient, who attended the doctor´s office for lachrymation; the biomicroscopy evinced corneal attenuation and 360º circumferencial marginal opacity with a well differentiated line of lipoid deposits and peripheral nasal vascularization. Scheimpflug camera images showed a preserved central corneal thickness with peripheral attenuation. The pachymetric map showed lower values in the nasal area coinciding with areas of higher keratometric value in the curvature map and with the area of greater attenuation according to biomicroscopy. Due to the described characteristics, it has to do with Terrien´s Marginal Degeneration. This is a slow progressive disease, with no effect for the central cornea, so its prognosis is generally good. In those cases where the disease causes decemetocele or peripheral perforation, the patient may need penetrating lamellar peripheral keratoplasty(AU)

Cambios corneales producidos por la cirugía refractiva con excimer láser: revisión de tema / Changes produced by corneal refractive surgery with excimer laser: a review

RESUMEN El auge de la cirugía refractiva con excimer láser en las últimas dos décadas se ha reflejado en que un grupo creciente de pacientes con antecedente de este procedimiento necesitan ahora cirugía de catarata. Debido a las modificaciones generadas en la córnea por la fotoablación con el láser, la determinación del poder corneal necesario para el cálculo del poder del lente intraocular a implantar en la cirugía de catarata, es difícil. Teniendo en cuenta estos aspectos se hace una revisión de las causas de estos errores de medición y los abordajes existentes para minimizar su impacto. MÉD.UIS. 2017;30(1):99-105.

ABSTRACT The rise of excimer laser refractive surgery in the last two decades has been reflected in a growing group of patients with a history of this procedure who now need cataract surgery. Because the generated modifications to the cornea with the laser photoablation, determining the corneal power, necessary for calculating the power of the intraocular lens to be implanted during the cataract surgery, is difficult. We review the causes of these errors of measurement and existing approaches to minimize its impact. MÉD.UIS. 2017;30(1):99-105.

Clinical Outcomes of an Optimized Prolate Ablation Procedure for Correcting Residual Refractive Errors Following Laser Surgery

PURPOSE: The purpose of this study was to investigate the clinical efficacy of an optimized prolate ablation procedure for correcting residual refractive errors following laser surgery. METHODS: We analyzed 24 eyes of 15 patients who underwent an optimized prolate ablation procedure for the correction of residual refractive errors following laser in situ keratomileusis, laser-assisted subepithelial keratectomy, or photorefractive keratectomy surgeries. Preoperative ophthalmic examinations were performed, and uncorrected distance visual acuity, corrected distance visual acuity, manifest refraction values (sphere, cylinder, and spherical equivalent), point spread function, modulation transfer function, corneal asphericity (Q value), ocular aberrations, and corneal haze measurements were obtained postoperatively at 1, 3, and 6 months. RESULTS: Uncorrected distance visual acuity improved and refractive errors decreased significantly at 1, 3, and 6 months postoperatively. Total coma aberration increased at 3 and 6 months postoperatively, while changes in all other aberrations were not statistically significant. Similarly, no significant changes in point spread function were detected, but modulation transfer function increased significantly at the postoperative time points measured. CONCLUSIONS: The optimized prolate ablation procedure was effective in terms of improving visual acuity and objective visual performance for the correction of persistent refractive errors following laser surgery.

Validity of Tono-pachymetry for Measuring Corrected Intraocular Pressure in Non-surgical and Post-photorefractive Keratectomy Eyes

PURPOSE: To assess the validity of central corneal thickness (CCT) and corrected intraocular pressure (IOP) values obtained by tono-pachymetry in non-surgical and post-photorefractive keratectomy (PRK) eyes. METHODS: For the study, 108 young healthy participants and 108 patients who had PRK were enrolled. Measurements were randomly performed by tono-pachymetry, ultrasonic (US) pachymetry, and Goldmann applanation tonometry (GAT). CCT measurement by tono-pachymetry was compared to that of US pachymetry. The corrected IOP value obtained by tono-pachymetry was compared to that obtained by US pachymetry and GAT. The corrected IOP from US pachymetry and GAT was calculated using the identical compensation formula built into the tono-pachymetry. Bland-Altman plot and paired t-test were conducted to evaluate the between-method agreements. RESULTS: The mean CCT measurement using tono-pachymetry was significantly greater by 7.3 µm in non-surgical eyes (p < 0.001) and 17.8 µm in post-PRK eyes (p < 0.001) compared with US pachymetry. Differences were significant in both Bland-Altman plotand paired t-test. The mean difference of corrected IOP values obtained by tono-pachymetry and calculated from measurements by US pachymetry and GAT was 0.33 ± 0.87 mmHg in non-surgical eyes and 0.57 ± 1.08 mmHg in post-PRK eyes. The differences in the Bland-Altman plot were not significant. CONCLUSIONS: The CCT measurement determined using tono-pachymetrywas significantly thicker than that of US pachymetry. The difference in CCT was greater in post-PRK eyes than in non-surgical eyes. However, the corrected IOP value obtained by tono-pachymetry showed reasonable agreement with that calculated from US pachymetry and GAT measurements.

Queratometrías por Pentacam y método de Maloney en pacientes con catarata y cirugía refractiva corneal previa / Keratometries taken with Pentacam and Maloney method in patients with cataract and previous corneal refractive surgery

Objetivo: comparar las queratometrías obtenidas por el Pentacam y el método de Maloney en pacientes con catarata, operados previamente de cirugía refractiva corneal. Métodos: se realizó un estudio descriptivo, longitudinal, prospectivo y comparativo entre los valores queratométricos obtenidos mediante el método de Maloney y el Pentacam en pacientes con catarata y cirugía refractiva corneal previa. Se estudiaron 41 ojos de 31 pacientes distribuidos en dos grupos, con 23 y 18 ojos para Maloney y Pentacam respectivamente. La información de la base de datos fue procesada con el software SPSS versión 11.0 para Window. Se trabajó con un nivel de confianza del 95 por ciento y de error inferior al 0,05 por ciento. Resultados: en ambos grupos prevaleció el astigmatismo miópico (simple o compuesto), lo cual se encontró en 14 ojos (60,9 por ciento) del grupo 1 y 16 ojos (89 por ciento) del grupo 2. La mayoría de los ojos estudiados (37) tenían queratotomía radiada, y solo 4,3 del Grupo 1 y 1 del Grupo 2 tenían LASEK miópico. La queratometría promedio obtenida por el método de Maloney fue de 37,55 D, mientras que el valor promedio brindado por el Pentacam (EKR a 4,0 mm) fue de 39,18 D, con una diferencia promedio de 1,64 D, que fue significativa (p= 0,019). Conclusiones: los valores queratométricos aportados por el método de Maloney y las EKR a 4,0 mm del modo Holladay Report del Pentacam presentan diferencias significativas en pacientes con queratotomía radiada previa(AU)

Objective: to compare the keratometries with Pentacam and with Maloney method in patients with cataract, who had previously undergone refractive corneal surgery. Methods: comparative, prospective, descriptive and longitudinal study of keratometric values estimated with Pentacam camera and with Maloney's method in patients with cataract and previous corneal refractive surgery. Forty one eyes were distributed into two groups; twenty three were studied by Maloney method and 18 by Pentacam. Database information was processed by was processed by version 11.0 SPSS software for Windows. The confidence interval was 95 percent and the error margin below 0.05 percent. Results: myopic astigmatism (simple or compound) prevailed and it was found in 14 eyes (60.9 percent) of Group 1 and in 16 eyes (89 percent) of group 2. Most of the studied eyes (37) had radiated keratotomy and just 4.3 in group 1 and one in group 2 had myopic LASEK. The average keratometry with Maloney's method was 37.55 D whereas the average value provided by the Pentacam (EKR at 4,0 mm) was 39.18 D, with a significant average difference of 1.64 D (p= 0.019). Conclusions: the keratometric values estimated by Maloney's method and the EKR at 4,0 mm from the Holladay Report of Pentacam show significant differences in patients with previous radiated keratotomy(AU)

Queratectomía fototerapéutica en la queratopatía en banda / Phototherapeutic keratectomy in the band keratopathy

Las opciones quirúrgicas con la utilización del láser excímer en determinadas entidades corneales reporta importantes beneficios. La queratopatía en banda, considerada como una degeneración de la córnea superficial caracterizada por la presencia de depósitos de calcio en la membrana de Bowman, es una de las afecciones corneales que han mostrado alentadores resultados con la realización de la queratectomía fototerapéutica. Se presenta un paciente de 68 años, del sexo femenino y piel blanca, con antecedentes de uveítis anterior. En la consulta refirió sensación de cuerpo extraño del ojo derecho. En la exploración oftalmológica del ojo derecho se apreciaron en la córnea superficial depósitos de color blanco-grisáceo de localización interpalpebral. Los estudios refractivos realizados constataron una disminución marcada de la agudeza visual de cuenta dedos en ambos ojos. Se le realizó queratectomía fototerapéutica del ojo derecho y mejoró la sintomatología ocular(AU)

The surgical options with the use of the excímer laser in certain corneal diseases provide important benefits. Band keratopahy, considered a superficial corneal degeneration characterized by the presence of calcific bands in Bowman's membrane, is one of the corneal affections that have shown encouraging results with the performance of phototherapeutic keratectomy. Here is a 68 years-old Caucasian female with no history of previous uveitis. At the ophthalmological service, she said she felt some foreign body in her right eye. The eye examination revealed white-gray superficial deposits of intereyelid location in the cornea. The refractive studies confirmed a marked reduction of visual acuity in both eyes. The patient underwent phototherapeutic keratectomy and her ocular symptoms improved(AU)