Purpose: To compare the accuracy of a newly developed intraocular lens (IOL) power formula (VRF-G) with twelve existing formulas (Barret Universal II, EVO 2.0, Haigis, Hill-RBF 2.0, Hoffer Q, Holladay 1, Kane, Næeser 2, PEARL-DGS, SRK/T, T2 and VRF). Methods: Retrospective case series including 828 patients having uncomplicated cataract surgery with the implantation of a single IOL model (SN60WF). Using optimised constants, refraction prediction error of each formula was calculated for each eye. Subgroup analysis was performed based on the axial length (short ≤22.0mm; medium >22.0mm to <26.0mm; long ≥26.0mm). Main outcomes included mean prediction error (ME) mean (MAE) and median absolute error (MedAE), in diopters (D), and the percentage of eyes within ±0.25D, ±0.50D, ±0.75D and ±1.00D. Results: Formulas absolute errors were statistically different among them (p<0.001), with Kane having the lowest MAE of all formulas, followed by EVO 2.0 and VRF-G, which had the lowest MedAE. The Kane formula had the highest percentage of eyes within ±0.25D (47.0%) and ±1.00D (97.7%) and the VRF-G formula had the highest percentage of eyes within ±0.50D (79.5%). For all AL subgroups, Kane, EVO 2.0 and VRF-G formulas had the most accurate performances (lowest MAE). Conclusion: New generation formulas may help us in achieving better refractive results, lowering the variance in accuracy in extreme eyes - Kane, EVO 2.0 and VRF-G formulas are promising candidates to fulfil that goal.

Introdução: O iStent® “trabecular micro-bypass stent modelo GTS100R/L” tem resultados comprovados na cirurgia do glaucoma de ângulo aberto. Descrito como cirurgia ab interno do canal de Schlemm, visa criar um bypass entre a câmara anterior e este canal, ultrapassando a malha trabecular – principal resistência à drenagem de humor aquoso. Os autores visam estudar o papel do OCT de segmento anterior (SA) na localização do iStent® e uma eventual relação entre o seu posicionamento a eficácia hipotensora. Material e Métodos: Estudo transversal descritivo em que se avaliaram 17 olhos de 17 doentes submetidos a cirurgia de facoemulsificação combinada com iStent®, com um ano de follow-up. Estudou-se o ângulo irido-corneano com OCT spectral domain de SA (Heidelberg Spectralis®) e realizou-se uma avaliação oftalmológica que incluiu medição da pressão intra-ocular (PIO) com tonómetro de Goldmann e gonioscopia. Resultados: Em todos os olhos foi possível localizar o iStent® no ângulo da câmara anterior, porém apenas 4 pareciam estar no canal de Schlemm, estando os restantes na malha trabecular ou esporão escleral. Nos 4 olhos com implante no canal verificou-se uma redução média da PIO de 6,0 mmHg relativamente aos valores pré-operatórios, nos restantes essa redução foi 5,36 mmHg. Esta diferença não é estatisticamente significativa (p>0,05). Conclusões: O OCT spectral domain de SA é um método eficiente para determinar o posicionamento do iStent® no ângulo. Apesar da maioria das extremidades distais dos dispositivos não se encontrarem no canal de Schlemm, estes ultrapassaram a resistência da malha trabecular, pelo que a localização não parece comprometer a eficácia hipotensora.

Multifocal intraocular lenses (MF IOLs) have concentric optical zones with different dioptric power, enabling patients to have good visual acuity at multiple focal points. However, several optical limitations have been attributed to this particular design. The purpose of this study is to access the effect of MF IOLs design on the accuracy of retinal optical coherence tomography (OCT). Cross-sectional study conducted at the Refractive Surgery Department of Central Lisbon Hospital Center. Twenty-three eyes of 15 patients with a diffractive MF IOL and 27 eyes of 15 patients with an aspheric monofocal IOL were included in this study. All patients underwent OCT macular scans using Heidelberg Spectralis®. Macular thickness and volume values and image quality (Q factor) were compared between the two groups. There were no statistically significant differences between both groups regarding macular thickness or volume measurements. Retinal OCT image quality was significantly lower in the MF IOL group (p < 0.01). MF IOLs are associated with a significant decrease in OCT image quality. However, this fact does not seem to compromise the accuracy of spectral domain OCT retinal measurements.

Cataracts result from an aggregation of proteins present in the lens of the humaneye, which over time can cause partial or total loss of vision. Currently, about65.2 million people suffer from cataracts, making it the leading cause of visionloss worldwide. The current treatment for cataracts is surgery.The most used surgical treatment to remove the cataract and recover visual acuityis called phacoemulsification. This procedure requires the use of high-intensityultrasound or laser beams to fragment the cataractous lens followed by aspirationand implant of an artificial intraocular lens.The success of this technique heavily depends on the application of an appropriateenergy level for lens fragmentation. An incorrect estimation of this energylevel could result in the rupture of the lens’s posterior capsule and the loss of cornealendothelial cells. Currently, the energy level of the ultrasound is estimatedbased on a qualitative assessment of cataract hardness.For this purpose, images of the lens are observed through a slit lamp attached toa microscope to assess its opacity.In this study, using ultrasonic signals (A-scans), the aim is to locate the maininterfaces of the human eye (anterior and posterior lens) and detect the stiffnessassociated with each type of cataract (incipient cataract or mature cataract), if thisexists.The propagation of ultrasonic signals will interact with the different media of theeye’s structures, returning an echo from each interface through which the signalpasses through. By this echo, it will be possible to analyze the position of eyestructures, as well as the location and hardness of the cataract.In the initial phase, using a rule-based algorithm, the goal is to detect the eye’sinterfaces. Subsequently, employing machine learning methods, the aim is toautomatically detect and classify the existing type and severity of cataract.

Purpose: Cataract and glaucoma are two of the most common ocular comorbidities. Cataract surgery has been shown to influence intra-ocular pressure (IOP) in patients with glaucoma; nevertheless, the extent of this effect remains controversial, especially in patients with open-angle glaucoma (OAG). The aim of this review is to determine the real effect of cataract surgery on IOP change in patients with OAG, focusing on data retrieved from randomised controlled trials (RCTs). Methods: A systematic review was performed, including six different RCTs that studied the net effect of cataract surgery on IOP. Eligibility criteria required a full washout from hypotensive therapy, allowing accurate measurement of unmedicated IOP, both before and after surgery. Results: Included studies revealed a consistent reduction on IOP occurring after surgery, varying between 4.1 and 8.5 mmHg depending on the RCT. There was also a decrease in the number of glaucoma medications, with a mean reduction of 0.2-1.0 agents postoperatively. Evaluation of adverse outcomes of cataract surgery showed a very favourable safety profile. Conclusion: Although the role of cataract surgery in the algorithm of glaucoma treatment remains to be established, this review highlights a consistent decrease on IOP following surgery and a reduced dependency on glaucoma medications. Potential downgrade in medication can thus be considered in well-controlled glaucoma patients after phacoemulsification.

As cataratas são uma das principais causas de cegueira em cães, e caracterizam-se por uma opacificação focal ou difusa do cristalino que impede a passagem da luz para a retina. Apresentam etiologia multifatorial, nomeadamente a foto oxidação por ação da radiação ultravioleta que origina a formação de precipitados que se acumulam e agregam no cristalino formando a catarata, desequilíbrios eletrolíticos no conteúdo aquoso do cristalino, alterações nas membranas das células epiteliais cuboides do cristalino, devido a inflamações ou por ação de radicais livres, e ainda alterações das fibras e das células do cristalino por ação mecânica e alterações durante a embriogénese. As cataratas podem apresentar diversas etiologias, localizações e estadios de maturação. Quanto à origem podem classificar-se como hereditárias ou adquiridas; quanto à idade do animal podem ser congénitas, juvenis, adultas ou senis; podem-se apresentar em diferentes localizações capsulares, subcapsulares, corticais, nucleares ou equatoriais; e estadios de maturação - incipientes, imaturas, maduras ou hipermaduras. As cataratas senis são o tipo mais frequente em animais de companhia, ocorrem em animais geriátricos, apresentando-se frequentemente de forma bilateral e geralmente associados à idade ou a doenças e distúrbios metabólicos, como a diabetes mellitus. Os cães são os mais afetados, sendo rara em gatos. O tratamento mais comum e com elevada taxa de sucesso para cataratas avançadas consiste na remoção cirúrgica por facoemulsificação, uma técnica minimamente invasiva que substitui o cristalino opacificado por uma lente artificial, com recurso a tecnologia avançada. A avaliação diagnóstica prévia detalhada, incluindo exames como a eletrorretinografia e a ultrassonografia ocular, é crucial para garantir o sucesso do tratamento e minimizar complicações pós-operatórias. O presente trabalho visa relatar um caso clínico pouco comum, nomeadamente a catarata hipermadura unilateral num canídeo de cinco anos, de provável origem hereditária e sem nenhuma doença associada. Esta patologia está descrita como sendo mais frequente em animais de idade avançada (cataratas senis), normalmente a partir dos 11 anos de idade em cães de raças pequenas. Optou-se pelo tratamento cirúrgico aplicando a técnica da facoemulsificação, resultando na recuperação da visão do animal.

Cataracts are among the most common ocular diseases and are a leading cause of vision loss in dogs and humans. Jack Russell Terriers (JRT) and Labrador Retrievers (LR) are among the canine breeds most affected by cataracts. This study aimed to analyse the clinical features and the surgical outcome of cataracts in JRT and LR in an ophthalmological reference Veterinary Hospital in the United Kingdom. Medical records from JRT and LR diagnosed with cataracts between January of 2015 and December of 2016 were retrospectively evaluated. Data related with identification, clinical history, pre-operative features and surgical outcome were analysed. Forty-four dogs (81 eyes), including 26 JRT and 18 LR were enrolled in the study. Mean ages were 10.2 ± 3.2 years in JRT and 8.5 ± 3.7 years in LR. Twenty-eight (63.6%) were females and 16 (36.4%) were males. Most dogs (84.1%) presented bilateral cataracts. The most prevalent type of cataracts was nuclear and cortical in JRT (42.9%), and subcapsular in LR (31.3%). Significant differences in cataract location within the lens were detected between the two breeds (P=0.013).Senile in JRT (n=7) and genetic in LR (n=7) were the most common aetiologies. Concomitant ocular lesions were more frequent in dogs presented with cataracts in advanced stages, and included lens position (n=18; JRT: n=15; LR: n=3) and retinal alterations (n=8; JRT: n=2; LR: n=6), and glaucoma (n=6; JRT: n=5; LR: n=1). Thirty-three animals (75.0%, 51 eyes) were submitted to phacoemulsification with intraocular lens placement. Of these, 28 eyes (54.9%; JRT: n=21; LR: n=7) were visual, 17 eyes (33.3%; JRT: n=11; LR: n=6) presented impaired vision and six eyes (11.8%; JRT: n=0; LR: n=6) were blind at last clinical record. Post-operative complications were detected in 11 eyes (21.6%), being more frequent in dogs presented with cataracts in advanced stages. The obtained results and the multifactorial nature of cataracts call for further studies to identify and characterize the variables in a broader assessment, including other breeds and influencing factors.

The objective was to improve the visual acuity (VA) before facectomy and at the 15th-day of the post-operative phase, and its impact on elderly quality of life. We developed a prospective study, with 156 patients submitted to facectomy in an ophthalmologic campaign. According to the Snellen table, the mean VA in logMAR at 15 days post-surgery improved from 1.23 to 0.57 for elderly (p=0.000). When comparing the quality of life means using the quality of life tool Visual Functioning Questionnaire (VQF-25), the subdomain general vision presented the highest difference between means before and after facectomy (from 29.65 to 89.87). The correlation analysis pointed that the VA improved general satisfaction for far activities, ocular pain, mental health, and dependency, resulting in a positive impact on elderly quality of life. We brought up indicators to guide a more individualized therapy.

Por catarata, entende-se qualquer opacidade presente no cristalino, cápsula do cristalino ou ambos. As opacidades podem variar quanto ao tamanho, localização, forma e velocidade de progressão. Através da biomicroscopia com lâmpada de fenda é possível examiná-las com precisão, determinando sua localização e peculiaridades, propiciando um diagnóstico acurado e seguro. Devido à origem e aparência variáveis, muitos métodos de classificação têm sido utilizados. Classificação quanto à etiologia, grau de maturidade, localização e idade do paciente sáo apresentados nesta revisão. A remoção cirúrgica é a única forma de terapia efetiva para a enfermidade. Dentre as técnicas existentes, destaca-se a facoemulsificação endocapsular, por seus melhores resultados, não obstante seus altos custos, comparativamente às facectomias intra e extracapsulares clássicas.

ABSTRACT We here in report the case of a patient subjected to cataract surgery through phacoemulsification under local anesthetic block, without intra-operative complications. The patient presented important visual impairment in the first post-operative day. Fundoscopy showed pallor resembling cherry-red spots at the macula. Fluorescein angiography did not depict signs of vascular occlusion and the spectral-domain optical coherence tomography showed increased reflectivity in the inner layers of the retina, thus suggesting local thickening and edema. The current case led to the diagnostic hypothesis of transient retinal arterial occlusion.