Humanitarian missions and visual outcomes in cataract surgery: A literature review.

The limited accessibility to ophthalmological services in remote regions of developing countries poses a significant challenge in visual healthcare. Cataracts and refractive errors are prominent causes of visual impairment, and surgery, despite being an efficient option, faces barriers in developing countries due to financial and geographical constraints. Humanitarian missions play a vital role in addressing this issue. The improvement in the accuracy of calculating IOL power through techniques such as keratometry and biometry is a fundamental step towards optimizing surgical outcomes and the quality of life for patients in these underserved regions. In this context, the consideration of keratometry and immersion ultrasound biometry as preoperative assessment standards in cataract surgeries in developing countries is presented as a pertinent and advisable strategy.

Intracorneal implantation of a misdirected foldable intraocular lens during phacoemulsification surgery: a case report / Implantação intracorneana de uma lente intraocular dobrável direcionada incorretamente durante cirurgia de facoemulsificação: relato de caso

ABSTRACT A 59-year-old man presented with a unilateral blurring of vision in his left eye. His left eye's visual acuity was hand movements level. He underwent phacoemulsification surgery, and an intrastromal posterior chamber intraocular lens was implanted. The intrastromal intraocular lens was extracted and a new intraocular lens was implanted. Usinge the Snellen chart, the final best-corrected visual acuity was 20/40. With this case report, we wish to emphasize that a single stepwise clear corneal incision merged with wound-assisted intraocular lens injections can result in intraocular lens misdirection into the corneal stroma. As a result, while performing a misdirected intraocular lens removal, we recommend that the wound be carefully constructed.

RESUMO Um homem de 59 anos apresentou embaçamento visual unilateral no olho esquerdo. Sua acuidade visual nesse olho era no nível de movimentos da mão. O paciente havia se submetido a uma cirurgia de facoemulsificação em que foi feita a implantação intraestromal de uma lente intraocular de câmara posterior. Foi feita a extração dessa lente intraestromal intraocular e uma nova lente intraocular foi implantada. A melhor acuidade visual corrigida final foi de 20/40 pela tabela de Snellen. Com este relato de caso, os autores desejam apontar que uma incisão de degrau único em córnea clara, quando combinada com a injeção de uma lente ocular através da incisão, pode levar a um direcionamento incorreto da lente intraocular para dentro do estroma corneano. Portanto, recomenda-se uma construção cuidadosa da incisão ao se remover uma lente intraocular direcionada incorretamente.

El glistening de las lentes intraoculares: revisión de la literatura / Glistening on intraocular lenses: a review

El glistening en las lentes intraoculares (LIO) es un fenómeno en el que se forman diminutas microvacuolas llenas de agua dentro del material de la LIO, lo que hace que la luz se disperse y cree un efecto centelleante o reluciente. La presencia del glistening es frecuente en muchos tipos de materiales y modelos de LIO, y se ha estudiado ampliamente en los últimos años para conocer su incidencia, factores de riesgo, evolución y posible relevancia clínica. Clásicamente se ha estudiado in vitro en laboratorio o mediante fotografía obtenida con lámpara de hendidura. Sin embargo, son técnicas que requieren de un explorador experto, además de requerir mucho tiempo y un complejo procesado de las imágenes. En los últimos años, han surgido propuestas basadas en la cámara de Scheimpflug y en la tomografía de coherencia óptica como forma de simplificar el análisis del glistening en las LIO. Se ha descrito que tanto el proceso de fabricación, como el propio material acrílico hidrofóbico, y el tiempo desde la cirugía son factores de riesgo relacionados con la aparición de glistening. Además, aún se desconocen numerosas cuestiones relacionadas con este fenómeno, como la cantidad de puntos o el tamaño de los mismos necesarios para causar afectación de la función visual, ya que se han descrito diferentes fenómenos ópticos relacionados con el glistening de las LIO (AU)

The glistening in intraocular lenses (IOLs) is a phenomenon in which tiny water-filled microvacuoles form within the IOL material, causing light to scatter and create a sparkling or shimmering effect. The presence of glistening is common in many types of IOL materials and models and has been extensively studied in recent years to determine its incidence, risk factors, evolution, and possible clinical relevance. Classically, it has been studied in vitro in the laboratory or by means of photography obtained with a slit lamp, but these were techniques that required either specific technology or an expert explorer, complex image processing, and required a lot of time. In recent years, proposals based on the Scheimpflug camera and optical coherence tomography have emerged to try to simplify the analysis of glistening in IOLs. It has been described that the manufacturing process, the hydrophobic acrylic material, or the time since surgery are risk factors for the appearance of glistening. In addition, many issues related to this phenomenon are still unknown, such as not knowing from what number of points or their size they may have relevance to visual function since different optical phenomena related to glistening have been described on the IOLs (AU)

Desprendimiento de retina tras la cirugía de cristalino transparente con lentes intraoculares EDOF y multifocales: una revisión narrativa / Retinal detachment after refractive lens exchange with EDOF and multifocal intraocular lenses: A narrative review

La cirugía de cristalino transparente (RLE) permite corregir las ametropías y la presbicia mediante el reemplazo del cristalino por una lente intraocular (LIO), ya sea monofocal, multifocal (MIOL) o de profundidad de foco extendida (EDOF). El desprendimiento de retina (DR) es uno de los eventos adversos más graves tras la RLE. El objetivo de este estudio fue revisar la evidencia y los resultados clínicos relacionados con el riesgo de DR después de la RLE. Se realizó una búsqueda utilizando PubMed y un procedimiento de bola de nieve para identificar estudios originales y series de casos. Según la bibliografía, los pacientes < 60 años con longitudes axiales > 23 mm tienen el mayor riesgo de DR. Solo nueve artículos reportaron la agudeza visual (AV) tras el DR en RLE, y solo 25% de los ojos mostraron una AV > 20/40. Teniendo en cuenta que la disminución de la AV tras el DR se puede dar con todos los tipos de LIO independientemente de su diseño óptico, la actitud más acertada al realizar una RLE sería una cuidadosa selección del paciente, evitando aquellos ojos con factores de riesgo para DR (AU)

Refractive lens exchange (RLE) allows to correct ametropias and presbyopia by replacing the crystalline lens with a monofocal, extended depth of focus or multifocal intraocular lens (IOL). Retinal detachment (RD) is one of the most serious adverse events after RLE. This study aimed to review the evidence related to the risk of RD after RLE and its clinical outcomes. A search using PubMed and a snowball search approach was conducted to identify articles and case reports. According to the literature, patients <60 years old with axial lengths >23 mm have the higher postoperative risk of RD. Only nine articles reported visual acuity (VA) after RD in RLE, and only 25% of eyes had a VA>20/40. Considering that the decrease in VA might be uniform for all types of IOLs after RD, surgeons should focus on preventing the RD by means of selecting the appropriate patient, rather than choosing on a particular IOL optical design (AU)

Síndrome de Uveitis - Glaucoma - Hifema: Caso clínico

Introducción: El síndrome de uveítis-glaucoma-hifema (UGH) es una complicación infrecuente de las cirugías de catarata, debido a un roce mecánico ejercido por una lente intraocular (LIO) sobre el iris. Caso clínico: Un varón de 64 años, con antecedente de cirugía de catarata, presenta disminución de la agudeza visual y dolor en el ojo derecho. En el examen oftalmológico, se evidenciaron signos de uveítis anterior, presión intraocular (PIO) elevada, microhifema y una LIO de una pieza plegable en sulcus que provocaba un roce mecánico con la cara posterior del iris. El tratamiento médico fue insuficiente, por lo que se realizó una cirugía de explante de LIO de una pieza plegable y se reemplazó por una LIO de tres piezas plegables. La evolución posoperatoria fue favorable. Conclusión: Se debe sospechar de esta complicación, en pacientes con antecedente de cirugía de catarata, especialmente en casos en los cuales la LIO es de una pieza y ha sido implantada fuera del saco capsular.

Introduction: Uveitis-glaucoma-hyphema syndrome (UGH) is a rare complication of cataract surgery, due to mechanical chafing exerted by an intraocular lens (IOL) on the iris. Clinical case: A 64-year-old man with a history of cataract surgery, who presented decreased visual acuity and pain in the right eye. The ophthalmological examination revealed signs of anterior uveitis, elevated intraocular pressure (IOP), microhyphema, and a single-piece foldable IOL in the sulcus that caused a mechanical chafing with the posterior face of the iris. The medical treatment was insufficient; for this reason, a folding simple-piece IOL explant surgery was performed and replaced by a three-piece IOL. Postoperative evolution was favorable. Conclusion: Should be suspected this complication in patients with a history of cataract surgery, especially in cases in which the IOL is in single-piece and has been implanted outside the capsular bag.

Visual acuity, contrast sensitivity, and quality of life after bilateral implantation of multifocal diffractive intraocular lens / Acuidade visual, sensibilidade ao contraste e qualidade de vida após implante bilateral de lente intraocular multifocal difrativa

ABSTRACT Purpose: To evaluate visual outcomes, satisfaction, and quality of life of patients assisted in a Medical School hospital by the Brazilian Public Health System, who underwent bilateral diffractive multifocal intraocular lens implantation. Methods: Case series study with intervention, including 20 patients who underwent bilateral implantation of multifocal IOL EyeDiff® (Eyeol UK, Dunstable, UK). Exclusion criteria were corneal astigmatism >1.5 cylindrical diopters, previous ocular surgery or ocular disease, and intra- or postoperative complications. Patients were evaluated one, three, and six months after surgery. Monocular and binocular visual acuity for distance, intermediate and near, under photopic and mesopic conditions, monocular contrast sensitivity under photopic conditions, defocus curve, and quality of life were assessed. Results: Monocular distance-corrected visual acuity was 0.3 logMAR or better and monocular distance-corrected near visual acuity was J3 or better in all eyes under photopic conditions. Binocular distance-corrected near visual acuity was J1 in all cases. Contrast sensitivity was at the minimum level of normality for low and high spatial frequencies and within normal limits for intermediate spatial frequency. The quality of life questionnaire showed a high level of patient satisfaction. Conclusion: Bilateral implantation of the multifocal intraocular lens EyeDiff® provides patients with good visual acuity and quality of life, besides spectacle independence. The visual acuity and contrast sensitivity progressively improved between one and six postoperative months.

RESUMO Objetivo: Avaliar os resultados visuais, satisfação e qualidade de vida de pacientes atendidos em um hospital escola pelo Sistema Único de Saúde, submetidos a implante bilateral de lente intraocular multifocal difrativa. Métodos: Estudo tipo série de casos com intervenção, incluindo 20 pacientes submetidos a implante bilateral da lente intraocular multifocal difrativa EyeDiff® (Eyeol UK, Dunstable, UK). Os critérios de exclusão foram astigmatismo corneano >1,5 dioptria cilíndrica, cirurgia ou doença ocular prévias e complicações intraoperatórias ou pós-operatórias. Os pacientes foram avaliados após 1, 3 e 6 meses da cirurgia. Foram avaliadas a acuidade visual monocular e binocular para longe, intermediário e perto sob condições fotópica e mesópica, sensibilidade ao contraste monocular sob condições fotópicas, curva de defocus e questionário para avaliação da qualidade de vida. Resultados: A acuidade visual para longe corrigida monocular foi de 0,3 logMAR ou melhor e a acuidade visual para perto com correção para longe foi J3 ou melhor em todos os olhos, sob condições fotópicas. A acuidade visual binocular para perto com a correção para longe foi J1 em todos os casos. A sensibilidade ao contraste estava no nível mínimo de normalidade para frequências espaciais baixas e altas e abaixo dos limites normais para frequência espacial intermediária. O questionário de qualidade de vida mostrou que os pacientes apresentavam altos níveis de satisfação. Conclusão: O implante bilateral da lente intraocular multifocal EyeDiff® proporcionou boa acuidade visual e qualidade de vida, e independência de óculos aos pacientes. A acuidade visual e a sensibilidade ao contraste melhoraram progressivamente entre um e seis meses de pós-operatório.

Retinal detachment after refractive lens exchange: A narrative review.

Refractive lens exchange (RLE) allows to correct ametropias and presbyopia by replacing the crystalline lens with an extended depth of focus or multifocal intraocular lens (IOL). Retinal detachment (RD) is one of the most serious adverse events after RLE. This study aimed to review the evidence related to the risk of RD after RLE and clinical outcomes. A search using PubMed and a snowball search approach was conducted to identify articles and case reports. According to the literature, the risks of RD should be considered in patients <60 years old with axial lengths >23 mm. Only nine articles reported visual acuity (VA) after RD in RLE, and only 25% of eyes had a VA > 20/40. Considering that the decrease in VA might be uniform for all types of IOLs after RD, surgeons should focus on selecting the patient to prevent RD rather than on a particular IOL optical design based on the potential risk of DR.

Glistening on intraocular lenses: A review.

The glistening in intraocular lenses (IOLs) is a phenomenon in which tiny water-filled microvacuoles (MVs) form within the IOL material, causing light to scatter and create a sparkling or shimmering effect. The presence of glistening is common in many types of IOL materials and models and has been extensively studied in recent years to determine its incidence, risk factors, evolution, and possible clinical relevance. Classically, it has been studied in vitro in the laboratory or by means of photography obtained with a slit lamp, but these were techniques that required either specific technology or an expert explorer, complex image processing, and required a lot of time. In recent years, proposals based on the Scheimpflug camera and optical coherence tomography have emerged to try to simplify the analysis of glistening in IOLs. It has been described that the manufacturing process, the hydrophobic acrylic material, or the time since surgery are risk factors for the appearance of glistening. In addition, many issues related to this phenomenon are still unknown, such as not knowing from what number of points or their size they may have relevance to visual function since different optical phenomena related to glistening have been described on the IOLs.

18-month results of double-fanged 5-0 polypropylene suture transscleral bag fixation in subluxated cataracts / Resultados de 18 meses da técnica double fanged com sutura de 5-0 polipropileno para fixação transescleral de saco capsular em cataratas subluxadas

ABSTRACT Purpose: To evaluate the stability and efficacy of the double-flanged 5-0 polypropylene suture to fixate subluxated cataracts at 18 months and the possible complications of this new technique Methods: This technique uses a 5-0 polypropylene monofilament to create two flanges with a thermocautery, for fixation of a capsular tension segment to the sclera to fix the subluxated capsular bag. This technique was implemented in 17 eyes requiring intraocular lens implantation in a setting of zonular dialysis due to trauma, Marfan syndrome, microspherophakia, idiopathic disease, and post-phacoemulsification status. Results: Follow-up of the patients occurred at 18 months. Best-corrected visual acuity improved significantly from 0.85 to 0.39 (logMAR), whereas the spherical and cylindrical refractive errors and intraocular pressure remained stable from preoperation. No suture photodegradation or pseudophacodonesis were detected. Conclusion: The double-flanged 5-0 polypropylene suture transscleral bag fixation technique has shown favorable long-term outcomes in terms of bag intraocular lens/complex fixation and stability. In eyes with zonular weakness or dialysis, this technique appears to be a safe and knotless option for cataract surgery.

RESUMO Objetivo: Avaliar a estabilidade e eficácia da técnica double-flanged com sutura de 5-0 polipropileno para fixação de cataratas subluxadas aos 18 meses e as possíveis complicações desta nova técnica. Métodos: Esta técnica utiliza um monofilamento de polipropileno 5-0 para criar dois flanges com um termocautério para fixar um Segmento de Tensão Capsular na esclera a fim de estabilizar o saco capsular subluxado. Esta técnica foi implementada em 17 olhos que necessitavam do implante de lente intraocular em casos de diálise zonular devido a trauma, síndrome de Marfan, microesferofacia, subluxação idiopática ou pós-facoemulsificação que provocou subulxação do saco capsular intraoperatória. Resultados: O seguimento dos pacientes foi de 18 meses. A acuidade visual corrigida melhorou significativamente de 0,85 para 0,39 (logMAR), enquanto os erros de refração esféricos e cilíndricos e a pressão intraocular permaneceram estáveis. Nenhuma fotodegradação de sutura ou pseudofacodonese foi encontrada. Conclusão: A técnica double-flanged para fixação transescleral de saco capsular com sutura de 5-0 polipropileno mostrou resultados de estabilidade de longo prazo para o complexo lente/saco capsular. Então, aparenta ser uma opção segura para cirurgia de catarata, sem necessidade pontos, em olhos com fraqueza zonular ou diálise.

Ultrabiomicroscopía ultrasónica y estabilidad de la lente intraocular en pacientes con miopía axial sometidos a cirugía de facoemulsificación.

PURPOSE: To evaluate the stability and the refractive error of the different intraocular lens (IOL) after cataract surgery. METHOD: Retrospective, observational and single-center study. Patients diagnosed with cataract and myopia who underwent a phacoemulsification surgery with intraocular lens placement without complications were included. All patients underwent a complete ophthalmological examination, ultrasound biomicroscopy was performed at 2 weeks, 1 and 3 months after surgery. Descriptive statistics were performed using measures of central tendency and comparative analyzes. A value of p < 0.05 was considered significant. RESULTS: Thirty-one subjects with a diagnosis of axial myopia and senile cataract were included, 20 women (64.5%) and 11 men (35.5%), with a mean age was 62.8 ± 13.14 years. The IOL displacement were not different for the upper, lower, temporal and nasal quadrants; however, we observed a tendency to inclination to the temporal sector (p = 0.054) between the first and third postoperative month. Therefore, the were no significant differences in spherical equivalent between groups postoperatively. CONCLUSIONS: The inclination of the IOL did not change over time after surgery, the changes were similar with the different three types of IOL.

OBJETIVO: Evaluar la estabilidad y el desplazamiento de diferentes lentes intraoculares (LIO) a los 3 meses y los cambios refractivos asociados después de la facoemulsificación. MÉTODO: Estudio retrospectivo, observacional y unicéntrico. Se revisaron expedientes de pacientes sometidos a cirugía de facoemulsificación con colocación de LIO. Se realizó un examen oftalmológico completo, ultrabiomicroscopía a las 2 semanas, 1 y 3 meses después de la cirugía. Se realizó estadística descriptiva y análisis comparativos. Se tomó como diferencia significativa un valor de p < 0.05. RESULTADOS: Se incluyeron 31 ojos con diagnóstico de miopía y catarata senil, 20 mujeres (64.5%) y 11 hombres (35.5%), con una edad media de 62.8 ± 13.14 años. En cuanto al desplazamiento de la LIO, no se observaron diferencias significativas para los cuadrantes superior, inferior, temporal y nasal. Se observa una tendencia hacia temporal (p = 0.054) entre el primer y el tercer mes posoperatorios. El equivalente esférico tampoco mostró diferencias. CONCLUSIONES: El desplazamiento de la LIO no cambió con el tiempo después de la facoemulsificación. Los cambios fueron similares con los tres diferentes tipos de LIO y al compararlos proporcionan estabilidad refractiva en pacientes miopes.

Scleral fixation of iris-Intraocular lens complex (Reper®) with Canabrava double-flanged technique: a case report / Fixação escleral de um complexo íris-lente intraocular (Reper®) com técnica de flange duplo de Canabrava: relato de caso

ABSTRACT A 38-year-old patient who developed aphakia and aniridia secondary to trauma suffered from vision loss. To improve her vision, an iris-intraocular lens complex (Reper®) was fixed to the sclera with Canabrava's double-flanged technique. There was a satisfactory increase in the patient's visual acuity and no complications were observed during the 6-months follow-up. Canabrava technique simplifies and improves the fixation of the iris-intraocular lens complex to the sclera. It is a safe option that does not require scleral flaps or knots.

RESUMO Uma paciente de 38 anos desenvolveu afacia e ani­ridia secundárias a um trauma, levando à perda da visão. Para melhorar sua visão, um complexo de íris e lente intraocular (Reper®) foi fixado à esclera com a técnica de flange duplo de Canabrava. Houve um aumento satisfatório na acuidade visual do paciente e nenhuma complicação foi observada durante o acompanhamento de 6 meses. A técnica de Canabrava simplifica e melhora a fixação do complexo de íris e lente intraocular na esclera. É uma opção segura que não requer retalhos ou pontos esclerais.

Relación de los planos anatómicos del cristalino con la posición real del lente intraocular / Relationship of the Anatomical Planes of the Crystalline lens to the Actual Position of the Intraocular Lens

Objetivo: Determinar la relación de los planos anatómicos del cristalino con la posición real de la lente intraocular en pacientes con diagnóstico de catarata atendidos en el Centro de Microcirugía Ocular del Instituto Cubano de Oftalmología durante el período de enero del 2018 a enero 2021. Métodos: Se realizó un estudio observacional, descriptivo, prospectivo longitudinal en 89 ojos de 67 pacientes operados de catarata con implante de lente intraocular (LIO) por técnica de facoemulsificación. Se empleó para el cálculo del poder de la lente el IOL Master 700 y la fórmula de SRK/T. Se utilizó la imagen de OCT ofrecida por el IOL Máster 700 para determinar el plano ecuatorial y plano central del cristalino, así como la posición real de la lente intraocular. Resultados: Predominó el grupo de edad entre 60 - 79 años, el sexo femenino representó el 53 por ciento. Los ojos tamaño promedio y las medidas biométricas oculares en valores promedios estándar fueron los más representativos. El plano ecuatorial mostró menos diferencia con la posición real de la lente intraocular en comparación con la diferencia evidenciada entre el plano central y la posición real de la lente. La adecuada posición del lente intraocular calculado en la bolsa capsular independiente a la longitud axial, permitió obtener un resultado refractivo en correspondencia al esperado previo a la cirugía. Conclusión: Los parámetros anatómicos del cristalino (plano ecuatorial, plano central) constituyen variables importantes a tener en cuenta para el desarrollo y perfeccionamiento de las fórmulas para el cálculo del lente intraocular(AU)

Purpose: To determine the relationship of the anatomical planes of the crystalline lens with the actual position of the intraocular lens in patients with a diagnosis of cataract seen at the Ocular Microsurgery Center of the Cuban Institute of Ophthalmology during the period January 2018 and January 2021. Methods: An observational, descriptive, prospective longitudinal study was performed in 89 eyes of 67 patients operated on for cataract with intraocular lens implantation (IOL) by phacoemulsification technique. The IOL Master 700 and the SRK/T formula were used to calculate lens power. The OCT image provided by the IOL Master 700 was used to determine the equatorial plane and central plane of the crystalline lens, as well as the actual position of the intraocular lens. Results: The age group 60-79 years was predominant, female gender represented 53 percent. Average eye size and ocular biometric measurements in standard average values were the most representative. The equatorial plane showed less difference with the actual intraocular lens position compared to the difference evidenced between the central plane and the actual lens position. The adequate position of the intraocular lens calculated in the capsular bag independent to the axial length, allowed to obtain a refractive result in correspondence to the one expected before surgery. Conclusion: The anatomical parameters of the crystalline lens (equatorial plane, central plane) are important variables to be taken into account for the development and improvement of the formulas for the calculation of the intraocular lens(AU)

Repetibilidad y comparabilidad de un nuevo tomógrafo con tecnología SS-OCT en biometría óptica / Repeatability and comparability of a new swept-source optical coherence tomographer in optical biometry

Objetivo Evaluar la reproducibilidad en la medición de los parámetros biométricos utilizando un nuevo biómetro por tomografía de coherencia óptica con fuente de barrido y compararlo con un biómetro por reflectometría óptica de baja coherencia. Diseño Estudio observacional, descriptivo, de corte transversal. Método Se incluyeron 45 ojos derechos de 45 pacientes, a los que se realizó tres mediciones consecutivas con el biómetro Anterion y una con el biómetro Lenstar LS900. Se recogieron las siguientes variables: longitud axial (AXL), profundidad de cámara anterior (ACD), K plana (K1), K curva (K2), grosor corneal central (CCT), grosor del cristalino (LT) y distancia blanco-blanco (WTW). Para evaluar la repetibilidad se calculó el coeficiente de Pearson «R» y la desviación estándar intrasujeto (Sw). Para evaluar la comparabilidad entre los biómetros se utilizó el coeficiente de correlación de concordancia (CCC) y el coeficiente de correlación intraclase (CCI). Además, se realizaron gráficos de Bland-Altman para cada variable. Resultados El coeficiente de Pearson fue excelente y estadísticamente significativo en la evaluación de la repetibilidad para todas las variables. Los valores más altos fueron 0,987 (AXL), 0,983 (CCT) y 0,942 (ACD). No hubo diferencias estadísticamente significativas entre las repetidas mediciones con Anterion para todas las variables. Los valores de CCC y CCI fueron excelentes en la evaluación de las variables AXL, CCT y ACD, y fueron altos para las variables K1, K2, LT y WTW. Conclusiones La realización de una biometría óptica ocular con el biómetro SS-OCT Anterion es un procedimiento reproducible y comparable con el biómetro Lenstar LS900 (AU)

Purpose To evaluate the reproducibility in the measurement of ocular biometric parameters using a new swept-source optical coherence tomographer and its comparability with an optical low coherence reflectometry biometer. Design An observational, descriptive, cross-sectional study. Methods 45 right eyes of 45 patients diagnosed with cataract were included. Three successive biometric measurements with Anterion and one with Lenstar LS900 were performed on each patient. The following variables were collected: axial length (AXL), anterior chamber depth (ACD), flat K (K1), steep K (K2), central corneal thickness (CCT), lens thickness (LT) and white-to-white distance (WTW). The intrasubject standard deviation (Sw) and the coefficient of Pearson «R» were calculated in order to assess the repeatability. The intraclass correlation coefficient (ICC) and the concordance correlation coefficient (CCC) were obtained to evaluate the comparability between devices. A Bland–Altman plot was performed for each variable. Results The coefficient of Pearson was excellent and statistically significant in the evaluation of the repeatability in all the variables. The highest values were 0.987 (AXL), 0.983 (CCT) and 0.942 (ACD). There were no statically significant differences between repeated measurements with Anterion in all the parameters. The ICC and CCC were excellent in the evaluation of AXL, CCT and ACD, and were also good in regard to K1, K2, LT and WTW. Conclusions Performing biometry with the SS-OCT Anterion is a reliable and reproducible procedure, and it is comparable with the Lenstar LS900 (AU)

Repeatability and comparability of a new swept-source optical coherence tomographer in optical biometry.

PURPOSE: To evaluate the reproducibility in the measurement of ocular biometric parameters using a new swept-source optical coherence tomographer and its comparability with an optical low coherence reflectometry biometer. DESIGN: An observational, descriptive, cross-sectional study. METHODS: 45 right eyes of 45 patients diagnosed with cataract were included. Three successive biometric measurements with Anterion and one with Lenstar LS900 were performed on each patient. The following variables were collected: axial length (AXL), anterior chamber depth (ACD), flat K (K1), steep K (K2), central corneal thickness (CCT), lens thickness (LT) and white-to-white distance (WTW). The intrasubject standard deviation (Sw) and the coefficient of Pearson "R" were calculated in order to assess the repeatability. The intraclass correlation coefficient (ICC) and the concordance correlation coefficient (CCC) were obtained to evaluate the comparability between devices. A Bland-Altman plot was performed for each variable. RESULTS: The coefficient of Pearson was excellent and statistically significant in the evaluation of the repeatability in all the variables. The highest values were 0.987 (AXL), 0.983 (CCT) and 0.942 (ACD). There were no statically significant differences between repeated measurements with Anterion in all the parameters. The ICC and CCC were excellent in the evaluation of AXL, CCT and ACD, and were also good in regard to K1, K2, LT and WTW. CONCLUSIONS: Performing biometry with the SS-OCT Anterion is a reliable and reproducible procedure, and it is comparable with the Lenstar LS900.

Resultados del cálculo de la lente intraocular con fórmula Holladay 2 y Barret Universal 2 / Results of Intraocular Lens Calculation with Holladay 2 and Barret Universal 2 formula

Objetivo: Determinar los resultados refractivos con las fórmulas Holladay 2 y Barret Universal 2 a partir del cálculo de la lente intraocular en pacientes operados de catarata. Métodos: Se realizó un estudio descriptivo prospectivo y longitudinal con 60 ojos de 50 pacientes operados de catarata mediante la técnica de facoemulsificación. Se empleó para el cálculo de la lente el IOL Master 700 y el Pentacam AXL con la fórmula Holladay 2 y Barret Universal 2, respectivamente. Resultados: Predominó el sexo femenino y el grupo etario mayor de 60 años. Los ojos mayores de 26 mm mostraron la mayor diferencia entre el poder dióptrico de la lente intraocular que se implantó según Holladay y en menores de 22 mm según Barret Universal. Ambos grupos presentaron una disminución del equivalente esférico, siendo superior a 7 y 5 dioptrías en ojos mayores de 26 mm en el posoperatorio de ambas fórmulas. Posterior a la cirugía se observó una mejoría en la agudeza visual sin corrección y corregida de más de 4 líneas en la cartilla de Snellen, independiente de la longitud axial, para ambos grupos en estudio. Sin cambios significativos en el cilindro queratométrico. En el 70,0 por ciento de los casos, el resultado refractivo final estuvo en rango de la emetropía para el grupo Holladay 2 y el 66,7 por ciento para el grupo Barret Universal 2. Conclusiones: Ambas fórmulas resultan útiles para el cálculo de la lente intraocular en todos los rangos de longitud axial(AU)

Objective: To determine refractive outcomes with the Holladay 2 and Barret Universal 2 formulas from intraocular lens calculation in cataract surgery patients. Methods: A prospective and longitudinal descriptive study was performed with 60 eyes of 50 patients who underwent cataract surgery by phacoemulsification. The IOL Master 700 and Pentacam AXL with the Holladay 2 and Barret Universal 2 formula, respectively, were used to calculate the lens. Results: Female gender and age group older than 60 years predominated. Eyes larger than 26 mm showed the greatest difference between the dioptric power of the intraocular lens implanted according to Holladay and those smaller than 22 mm according to Barret Universal. Both groups presented a decrease of the spherical equivalent, being higher than 7 and 5 diopters in eyes larger than 26 mm postoperatively in both formulas. Postoperatively, there was an improvement in uncorrected and corrected visual acuity of more than 4 lines in the Snellen chart, independent of axial length, for both groups under study. No significant changes in keratometric cylinder. In 70.0 percent of the cases, the final refractive result was in the emmetropia range for the Holladay 2 group and 66.7 percent for the Barret Universal 2 group. Conclusions: Both formulas are useful for the calculation of the intraocular lens in all axial length ranges(AU)

Optimización de las constantes para el cálculo preciso de cinco modelos de lente intraocular / Optimization of constants for accurate calculation of five intraocular lens models

Objetivo: Optimizar las constantes utilizadas por las fórmulas SRK/T, SRK/T2, Holladay 1 y Hoffer Q para cinco modelos de lentes intraoculares (LIO), implantados durante la cirugía de catarata en el Instituto Cubano de Oftalmología (enero/2006-octubre/2019). Método: Se estudiaron retrospectivamente 47341 pacientes. Las constantes se optimizaron ajustando a cero el error de predicción promedio (EPm) y obteniendo el valor que arrojó el máximo número de ojos con error de predicción absoluto -EP- ≤; 0,25, tanto para la biometría ultrasónica como para la óptica. La eficacia de las constantes optimizadas se verificó mediante el análisis de los errores absolutos medio y mediano (EAM/EAMed) más bajos y el porcentaje de ojos en un intervalo determinado de error de predicción en función del valor de las constantes. También se analizaron el índice de rendimiento de la fórmula de Haigis y un nuevo índice introducido. Resultados: Las constantes optimizadas fueron significativamente diferentes de los valores del fabricante. Los valores obtenidos para EPm = 0 fueron diferentes a los mínimos de EAM y EAMed. El porcentaje de ojos con -EP- ≤ 0,25 y 0,50 D difirió cuando los criterios de optimización fueron diferentes. SRK/T y SRK/T2 mostraron los mejores rendimientos, según ambos índices. Conclusiones: Las constantes optimizadas mejoran los resultados postoperatorios para cada combinación LIO-fórmula. Diferentes criterios de optimización conducen a diferentes resultados. El EAM, el EAMed y el porcentaje de ojos con -EP- ≤; 0,50 D son parámetros válidos para comprobar el rendimiento de las fórmulas, hasta disponer de un índice único, fiable y consensuado(AU)

Objective: To optimize the constants used by the SRK/T, SRK/T2, Holladay 1 and Hoffer Q formulas for five intraocular lens (IOL) models implanted during cataract surgery at the Cuban Institute of Ophthalmology (January/2006-October/2019). Methods: 47341 patients were retrospectively studied. The constants were optimized by adjusting the average prediction error (EPm) to zero and obtaining the value that showed the maximum number of eyes with absolute prediction error -EP- ≤ 0.25, for both ultrasonic and optical biometry. The effectiveness of the optimized constants was verified by analyzing the lowest average and median absolute errors (EAM/EAMed) and the percentage of eyes in a given range of prediction error as a function of the value of the constants. The Haigis formula performance index and a newly introduced index were also analyzed. Results: The optimized constants were significantly different from the manufacturer's values. The values obtained for EPm = 0 were different from the EAM and EAMed minima. The percentage of eyes with -EP- ≤ 0.25 and 0.50 D differed when the optimization criteria were different. SRK/T and SRK/T2 showed the best performances, according to both indexes. Conclusions: Optimized constants improve postoperative outcomes for each IOL-formula combination. Different optimization criteria lead to different results. The EAM, the EAMed and the percentage of eyes with -EP- ≤ 0.50 D are valid parameters to check the performance of the formulas, until a single, reliable and consensual index is available(AU)

Difference between both eyes in the calculation of the dioptre power of the intraocular lens in a series of 7994 patients.

PURPOSE: To analyse the distribution of the difference between both eyes in the calculation of the dioptric power of the intraocular lens in a series of 7994 patients and the biometric variables that determine it. METHODS: The data of patients between 3 and 99 years old, residents of the city of Guayaquil and neighbouring sites, who received ocular biometry by partial optical coherence interferometry between 2004 and 2020 were reviewed. Ocular biometrics, including axial length (AL), anterior chamber depth (ACD), and the mean corneal dioptre power (CD), were measured by partial coherence interferometry. Refraction without or with cycloplegia was recorded in spherical equivalent (SE). The Haigis formula from the IOL Master instrument was used to calculate the dioptric power of the intraocular lens in both eyes. RESULTS: Data from the bilateral optical biometry of 7994 patients were analysed. The mean and standard deviation of AL, CD, ACD and dioptre power of the IOL were 23.66 ±â€¯1.25, 43.70 ±â€¯1.49, 3.34 ±â€¯0.40 and +20.46 ±â€¯3.84, respectively. 2538 (31.7%) patients had equal dioptre power of the IOL between both eyes. 3243 (40.6%) patients had a 0.50 D difference; 1162 (14.5%), 1.0 D; 425 (5.3%), 1.5 D. 626 patients (7.8%) had a difference in IOL dioptre of 2 D or more, with a maximum of 24 D. The asymmetry of AL between OU was ≥0.4 mm in 10.49%, while that of CD reached ≥1 D in 1.9%. CONCLUSIONS: 92.16% of patients had a difference within 1.5 D between both eyes in the calculation of the dioptre power of the intraocular lens. In case an eye is programmed in which it is impossible to perform a reliable biometry, either due to trauma or due to white or brunescent cataract, the calculation of the intraocular lens could be done taking as a reference the biometry of the contralateral eye.

Diferencia entre ambos ojos en el cálculo del poder dióptrico del lente intraocular en una serie de 7.994 pacientes / Difference between both eyes in the calculation of the dioptre power of the intraocular lens in a series of 7994 patients

Objetivo Analizar la distribución de la diferencia entre ambos ojos en el cálculo del poder dióptrico del lente intraocular (LIO) en una serie de 7.994 pacientes y las variables biométricas que la determinan. Métodos Se revisaron los datos de pacientes entre 3 y 99años, residentes en la ciudad de Guayaquil y sitios aledaños, que recibieron biometría ocular por interferometría de coherencia óptica parcial entre 2004 y 2020. La medición incluyó la longitud axial (LA), la profundidad de la cámara anterior (PCA) y la queratometría (Km) media. La refracción sin o con cicloplejia en dioptrías (D) fue registrada en equivalente esférico (EE). La fórmula de Haigis, incluida en el instrumento IOL Master, fue usada para realizar el cálculo del poder dióptrico del LIO en ambos ojos. Resultados Se analizaron los datos de la biometría óptica bilateral de 7.994 pacientes. El promedio y la desviación estándar de LA, Km, PCA y poder dióptrico del LIO fueron 23,66±1,25, 43,70±1,49, 3,34±0,40 y +20,46±3,84, respectivamente. Un total de 2.538 (31,7%) pacientes tuvieron igual poder dióptrico del LIO entre ambos ojos, y 3.243 (40,6%) pacientes tuvieron 0,50D de diferencia; 1,162 pacientes (14,5%), 1,0D; 425 pacientes (5,3%), 1,5D; 626 pacientes (7,8%) tuvieron una diferencia en el poder dióptrico del LIO de ≥2D, con un máximo de 24D. La asimetría de la LA entre ambos ojos fue ≥0,4mm en el 10,49%, mientras que el de la Km alcanzó ≥1D en 1,9%. Conclusiones El 92,2% de los pacientes tuvieron una diferencia dentro de 1,5D entre ambos ojos en el cálculo del poder dióptrico del LIO. En el caso de tratarse de un ojo en que resultara imposible realizar una biometría confiable, ya fuera por traumatismo o por catarata blanca o brunescente, el cálculo del LIO podría hacerse tomando como referencia la biometría del ojo contralateral (AU)

Purpose To analyse the distribution of the difference between both eyes in the calculation of the dioptric power of the intraocular lens in a series of 7994 patients and the biometric variables that determine it. Methods The data of patients between 3 and 99years old, residents of the city of Guayaquil and neighbouring sites, who received ocular biometry by partial optical coherence interferometry between 2004 and 2020 were reviewed. Ocular biometrics, including axial length (AL), anterior chamber depth (ACD), and the mean corneal dioptre power (CD), were measured by partial coherence interferometry. Refraction without or with cycloplegia was recorded in spherical equivalent (SE). The Haigis formula from the IOL Master instrument was used to calculate the dioptric power of the intraocular lens in both eyes. Results Data from the bilateral optical biometry of 7994 patients were analysed. The mean and standard deviation of AL, CD, ACD and dioptre power of the IOL were 23.66±1.25, 43.70±1.49, 3.34±0.40 and +20.46±3.84, respectively. 2538 (31.7%) patients had equal dioptre power of the IOL between both eyes. 3243 (40.6%) patients had a 0.50D difference; 1162 (14.5%), 1.0D; 425 (5.3%), 1.5D. 626 patients (7.8%) had a difference in IOL dioptre of 2D or more, with a maximum of 24D. The asymmetry of AL between OU was ≥0.4mm in 10.49%, while that of CD reached ≥1D in 1.9%. Conclusions 92.16% of patients had a difference within 1.5D between both eyes in the calculation of the dioptre power of the intraocular lens. In case an eye is programmed in which it is impossible to perform a reliable biometry, either due to trauma or due to white or brunescent cataract, the calculation of the intraocular lens could be done taking as a reference the biometry of the contralateral eye (AU)

Equivalent keratometer reading para cálculo biométrico em córneas assimétricas: série de casos / Equivalent keratometer reading tool for biometric calculation in asymmetric corneas: case series

RESUMO A acurácia do cálculo da lente intraocular não é perfeita, podendo ser comuns erros refrativos pós-operatórios, especialmente em pacientes submetidos à cirurgia refrativa prévia ou na presença de córneas assimétricas. O poder corneano após cirurgia refrativa pode ser medido com maior acurácia utilizando o mapa de poder óptico total na zona central de 4mm, com Orbscan II ou pelo mapa equivalent keratometric reading disponível no pentacam, com medidas centrais de 1,0, 2,0, 3,0 e 4,5mm. O objetivo desta série de casos é demonstrar a abordagem de quatro olhos em condições especiais corneanas, por meio do equivalent keratometric reading do pentacam para mensuração do poder corneano e o utilizando na biometria, em comparação com possíveis resultados obtidos com outras estratégias. Os quatro olhos foram submetidos a procedimentos refrativos prévios, e a lente intraocular escolhida a partir do uso do poder corneano calculado pelo equivalent keratometric reading mostrou excelentes resultados pós-operatórios.

ABSTRACT The accuracy of the intraocular lens calculation is not perfect, and postoperative refractive errors are common, especially in patients who have undergone previous refractive surgery or in presence of asymmetric corneas. Corneal power after refractive surgery can be more accurately measured using the total optical power map in the 4-mm central zone, by means of Orbscan II or equivalent keratometric reading map available on pentacam, with central measurements of 1.0, 2.0, 3.0 and 4.5 mm. The purpose of this case series is to demonstrate four approaches performed in special corneal conditions, using pentacam equivalent keratometric reading to measure corneal power and biometrics, and comparing with possible results obtained with other strategies. The four eyes were submitted to previous refractive procedures, and the intraocular lens chosen from the use of the corneal power calculated by equivalent keratometric reading showed excellent postoperative results.

Comparación entre las fórmulas SRK/T, Hoffer Q, Barrett Universal y HRBF para el cálculo del lente intraocular / Comparison of the formulas SRK/T, Hoffer Q, Barrett Universal and HRBF for intraocular lens calculation

Objetivo: Comparar la exactitud de las fórmulas SRK/T, Hoffer Q, Barrett Universal y HRBF en el cálculo del lente intraocular. Métodos: Se realizó un estudio descriptivo longitudinal prospectivo de 70 ojos de 70 pacientes operados de cirugía de catarata con implante de lente intraocular, de junio del año 2018 a junio del 2019, utilizando el IOL Master 700, en el Instituto Cubano de Oftalmología "Ramón Pando Ferrer". Se determinó la exactitud de cada fórmula respecto al error de predicción del equivalente esférico y se compararon entre sí. Resultados: Los pacientes entre 60 y 80 años constituyeron el 70,00 por ciento de los casos y el sexo femenino representó el 61,43 por ciento. Los ojos de tamaño medio representaron el 91,43 por ciento del total. No hubo diferencias en el error de predicción absoluto medio entre de las fórmulas analizadas para el rango total de longitudes axiales. La fórmula de Barrett tuvo el 65,71 por ciento de ojos con un error de predicción dentro de ± 0,50 D. El mayor porcentaje de ojos con un error mayor a 1 dioptría recayó sobre la Hoffer Q (10,00 por ciento). Conclusiones: El grupo etario más representado está entre 60 y 80 años y el sexo femenino es mayoritario. Predominan los ojos de tamaño medio y las mensuraciones biométricas dentro de los valores promedio estándar. Las fórmulas HRBF, SRK/T, Hoffer Q y Barrett predicen el resultado refractivo posoperatorio con una exactitud similar para el rango total de longitudes axiales. La fórmula de Barrett logra el mayor porcentaje de ojos con errores de predicción posoperatorios dentro del rango de la emetropía(AU)

Objective: Compare the accuracy of the formulas SRK/T, Hoffer Q, Barrett Universal and HRBF for intraocular lens calculation. Methods: A prospective longitudinal descriptive study was conducted of 70 eyes of 70 patients undergoing cataract surgery with intraocular lens implantation from June 2018 to June 2019 at Ramón Pando Ferrer Cuban Institute of Ophthalmology. In all cases IOL Master 700 was used for lens calculation. Determination of the accuracy of each formula in error prediction of the spherical equivalent was followed by a comparison of the formulas. Results: Patients aged 60-80 years were 70.00 percent of the cases; female sex represented 61.43 percent. Medium sized eyes were 91.43 percent of the total eyes examined. Mean absolute prediction error did not show any difference between the formulas analyzed for the total range of axial lengths. The Barrett formula spotted 65.71 percent of the eyes with a prediction error within ± 0.50 D. The highest percentage of eyes with an error greater than 1 diopter corresponded to the Hoffer Q formula (10.00 percent ). Conclusions: The best represented age group was 60-80 years; female sex prevailed. A predominance was found of medium size and biometric measurements within standard mean values. The formulas HRBF, SRK/T, Hoffer Q and Barrett predict the postoperative refractive result with similar accuracy throughout the total range of axial lengths. The Barrett formula achieves the highest percentage of eyes with postoperative prediction errors within the range of emmetropia(AU)