<b>Purpose:</b> Assess the relationship between tear film drying and sensation between blinks. <b>Methods:</b> MATLAB sampled a slitlamp video camera, a potentiometer and a microphone while subjects kept one eye open for as long as possible. 23 subjects rated the intensity of the ocular sensation while video and voice data were collected simultaneously. The tear drying on the cornea was measured. <b>Results:</b> The sensation was triphasic. Two linear functions described the latter 2 parts of the data (r &#8805; 0. 95). The correlation between TBUT and the elbow in the time-discomfort function was 0. 72. Extent of tear film drying was linearly correlated to time (median correlation = 0. 88). The correlation between the discomfort elbow and image elbow was 0. 93 with single data pair for each subject. Analysis of sensation characteristics showed significant differences between itching and burning for both intensity and time (p = 0. 03 and p = 0. 02 respectively). <b>Conclusions:</b> Simultaneous recording of ocular surface appearance, discomfort intensity and attributes of sensation provide novel information about the development of discomfort during ocular surface drying. The rapid increase in discomfort proceeding blinking has been quantified and the relationship between the time course of drying and discomfort is elucidated.

One of the most recent advancements in laser technology is the development of ultrashort pulsed femtosecond lasers (FSLs). FSLs are improving many fields due to their unique extreme precision, low energy and ablation characteristics. In the area of laser medicine, ophthalmic surgeries have seen very promising developments. Some of the most commonly performed surgical operations in the world, including laser-assisted in-situ keratomileusis (LASIK), lens replacement (cataract surgery), and keratoplasty (cornea transplant), now employ FSLs for their unique abilities that lead to improved clinical outcome and patient satisfaction. The application of FSLs in medical therapeutics is a recent development, and although they offer many benefits, FSLs also stimulate nonlinear optical effects (NOEs), many of which were insignificant with previously developed lasers. NOEs can change the laser characteristics during propagation through a medium, which can subsequently introduce unique safety concerns for the surrounding tissues. Traditional approaches for characterizing optical effects, laser performance, safety and efficacy do not properly account for NOEs, and there remains a lack of data that describe NOEs in clinically relevant procedures and tissues. As FSL technology continues to expand towards new applications, FSL induced NOEs need to be better understood in order to ensure safety as FSL medical devices and applications continue to evolve at a rapid pace. In order to improve the understanding of FSL-tissue interactions related to NOEs stimulated during laser beam propagation though corneal tissue, research investigations were conducted to evaluate corneal optical properties and determine how corneal tissue properties including corneal layer, collagen orientation and collagen crosslinking, and laser parameters including pulse energy, repetition rate and numerical aperture affect second and third-harmonic generation (HG) intensity, duration and efficiency. The results of these studies revealed that all laser parameters and tissue properties had a substantial influence on HG. The dynamic relationship between optical breakdown and HG was responsible for many observed changes in HG metrics. The results also demonstrated that the new generation of therapeutic FSLs has the potential to generate hazardous effects if not carefully controlled. Finally, recommendations are made to optimize current and guide future FSL applications.

The extracellular matrix (ECM) offers a protective shelter for cells and provides signaling paths important for cell to cell communication. ECM consists of basement membranes (BM) and interstitial matrix. BMs provide mechanical support for parenchymal cells, influence cell proliferation, survival, migration and differentiation. They are also important for tissue integrity. Laminins (LM) are the major non-collagenous component of BMs. Cell-ECM interactions, mediated by receptors, are indispensable during embryonic development, wound healing, remodeling and homeostasis of tissues. The integrins are the major cell-adhesion receptors. The expression of alpha11 integrin chain in the cornea is of great interest, as it is part of the alpha11beta1 integrin receptor for collagen type I, the predominant component of the corneal stroma. The aims were to thoroughly characterize the ECM in the developing and adult human eye, with particular focus on the cornea, LM and alpha11 integrin chains, and to examine alpha11 integrin chain in an animal model of corneal wound healing and remodeling. Human fetal eyes, 9-20 weeks of gestation (wg), and adult human corneas with different diagnosis were treated for immunohistochemistry with specific antibodies against LM and alpha11 integrin chains. Normal and knockout (ko) mice were treated with laser surgery to create a deep wound in the corneal stroma. The wound healing process was followed at different time points. The cellular source of alpha11 integrin chain was studied in cell cultures. In the fetal eyes, the BM of the corneal epithelium, the Descemet’s membrane (DM) and the Bruch’s membrane each had their specific combinations of LM chains and time line of development, whereas the lens capsule and the internal limiting membrane showed constant LM chain patterns. The epithelial BMs of normal and diseased adult corneas contained similar LM chains. The normal morphology of the epithelial BM was altered in the different diseases, particularly when scarring was present. In the scarred keratoconus corneas there were excessive LM chains. The majority of keratoconus corneas also expressed extra LM chains in the DM. At 10-17 wg alpha11 integrin chain was present in the human corneal stroma, especially in the anterior portion, but it was scarce at 20 wg, in normal adult corneas and in Fuchs’ endothelial dystrophy. In contrast, it was increased in the anterior portion of the stroma in keratoconus corneas with scarring. Alpha11 integrin ko mice had a defective healing with subsequent thinner corneas. Alpha11 integrin expression correlated to the presence of alpha-smooth muscle actin in vivo as well as in vitro. The distinct spatial and temporal patterns of distribution for alpha11 integrin and each of the LM chains suggest that they play an important role in human ocular differentiation. The selectively affected LM composition and the novel expression of alpha11 integrin chain in scarred keratoconus corneas as well as the pathologic healing in ko mice, indicate that alpha11 integrin and LM chains also play an important role in the process of corneal healing, remodeling and scarring and might participate in the pathogenesis of corneal disease. This knowledge is of practical importance for future topical therapeutic agents capable of modulating the corneal wound healing processes.

Syfte: Syftet med denna studie var att undersöka om preservative-associated transient hyperfluorescens (PATH) förekommer mer vid användandet av en multipurposevätska kontra vid användandet av ett kontaktlinsskötselsystem med väteperoxid. Metod: Försökspersonerna, vana kontaktlinsbärare och ögonfriska, tillpassades den mjuka kontaktlinsen Biofinity.  Gradering av ögats främre segment utfördes med och utan infärgning av fluorescein. Därefter fick försökspersonerna två olika kontaktlinsvätskor, Refine One Step och BioTrue, att använda som skötselsystem. Lott drogs för att bestämma vilken lins som skulle skötas med vilket skötselsystem. Dagen efter kom försökspersonen tillbaka när kontaktlinserna suttit i ögonen exakt två timmar, ögonens yttre segment färgades in med fluorescein för att gradera conjunctival och corneal staining. Linserna sattes i igen och försökspersonen kom tillbaka efter fyra timmar för ytterligare en gradering, med fluorescein. Sju samt fjorton dagar senare upprepades samma procedur som vid dag två. Resultat: Medelvärden för PATH vid användandet av de båda kontaktlinsvätskorna (BioTrue och Refine One Step) togs fram och parat t-test användes för att analysera resultaten: BioTrue besök 1-2 (p&lt;0,05), 3-4 (p&lt;0,05) samt 5-6 (p&lt;0,05); Refine One Step besök 1-2 (p=1), 3-4 (p=0,42) samt 5-6 (p=1). Detta visar statistiskt signifikant skillnad mellan PATH och en PHMB-baserad kontaktlinsvätska i kombination med silikonhydrogellins; ingen statistiskt signifikant skillnad visades vid användandet av ett väteperoxidsystem i kombination med en silikonhydrogellins. Slutsats: PATH förekommer vid kombinationen silikonhydrogel-lins och skötselsystem innehållandes konserveringsmedlet PHMB, men gav däremot ingen minskad komfort. För den kliniska verksamheten är PATH inget att oroa sig för då detta inte visar bioinkompatibilitet mellan kontaktlinsen och kontaktlinsvätskan. / The aim of this study was to evaluate if a greater amount of preservative-associated transient hyperfluorescence (PATH) is appearing when using a multipurpose-solution compared to using a hydrogen peroxide system as a cleaning and disinfecting scheme for contact lenses.   The subjects who participated in this study were contact lens wearers and had healthy eyes. Subjects were fitted with the soft contact lens Biofinity. The cornea and conjunctiva were examined with and without the color agent fluorescein using a slit lamp. The subjects received two different contact lens care systems: Refine One Step and BioTrue. The subjects were randomly assigned which lens that would go with which care system. The subjects came back the next day after having the contact lenses in the eyes for two hours. The contact lenses were removed, and fluorescein was instilled in order to grade corneal and conjunctival staining with the slit lamp. The contact lenses were then inserted again. The subject then came back after having the contact lenses in the eyes for four hours and another grading of corneal and conjunctival staining with the slit lamp was made. Seven and fourteen days later the subjects came back for the same procedure as day two.   Mean values for PATH when using both of the contact lens solutions (BioTrue and Refine One Step) were calculated and a paired t-test was used to analyze the results: BioTrue visit 1-2 (p&lt;0.05), 3-4 (p&lt;0.05) and 5-6 (p&lt;0.05); Refine One Step visit 1-2 (p=1), 3-4 (p=0.42) and 5-6 (p=1). This shows a statistically significant difference between PATH and PHMB-based contact lens solutions and silicone hydrogel contact lenses; no statistically significant difference between PATH and contact lens care system containing hydrogen peroxide in combination with a silicone hydrogel contact lens.   PATH is appearing when combining a silicone hydrogel contact lens together with a multipurpose solution containing the preservative agent PHMB but gave no decreased comfort. In the clinical work PATH is non-significant, the presence of PATH does not show bio incompatibility between silicone hydrogel lenses and preservative agents but is simply the fluorescein which binds to the preservative agent PHMB.

Atualmente, a avaliação das propriedades biomecânicas da córnea vem sendo considerada um parâmetro importante a ser determinado, uma vez que está relacionado a diversos procedimentos (diagnósticos e cirúrgicos) e oftalmopatias. Devido à complexa disposição de suas lamelas, o estroma corneal é considerado a camada que exerce maior influência sobre as propriedades elásticas da córnea. A busca por modelos experimentais no estudo das propriedades biomecânicas da córnea têm aumentado ultimamente, devido à dificuldade em se obter amostras de córnea humana para fins científicos. Logo, estudos comparativos entre a córnea humana e a suína vêm sendo desenvolvidos, e algumas similaridades foram identificadas entre estas duas espécies. O presente estudo tem como objetivo avaliar as propriedades biomecânicas de diferentes regiões da córnea suína por meio da microscopia da força atômica. Dezesseis bulbos oculares não escaldados, de oito animais da espécie suína, foram adquiridos em frigorífico local. Animais de diferentes raças, faixas de peso e idade foram utilizados neste estudo. Bulbos oculares frescos foram submetidos ao debridamento da camada epitelial da córnea, sendo posteriormente imersos em solução de dextran a 25%. Mensurações da paquimetria corneal em regiões central, superior, inferior, nasal e temporal foram realizadas em cada etapa do preparo das amostras. Após 24 horas submersas em solução de dextran, as córneas foram excisadas em fragmentos de aproximadamente 3 x 3 mm, conforme as regiões acima descritas. Tais fragmentos foram submetidos à avaliação pelo microscópio de força atômica, imersos em solução de dextran a 25%. Os valores do módulo de Young para cada fragmento foram obtidos com base no modelo de elasticidade de Hertz. O armazenamento de amostras de córnea em solução de dextran preveniu a hidratação excessiva destas, mantendo a paquimetria dentro dos valores considerados normais. Tanto a paquimetria quanto o módulo de elasticidade corneais não variaram dentre as regiões central, superior, inferior, nasal e temporal da córnea. A espessura e a elasticidade da córnea não diferiram frente à comparação de olhos contralaterais. Devido à facilidade de aquisição e aos resultados obtidos, a córnea suína pode ser empregada como modelo experimental na avaliação das propriedades biomecânicas corneais. / Currently, the assessment of corneal biomechanical properties has been considered an important parameter to be determined, since it is related to several procedures (diagnostic and surgical) and ocular diseases. Due to the complex arrangement of its lamellae, the corneal stroma is considered the layer that exert more influence on the elastic properties of the cornea. The demand for experimental models to study the biomechanical properties of the cornea has recently increased due to the difficulty in obtaining samples of human cornea for scientific purposes. Therefore, comparative studies between human and porcine cornea have been developed, and some similarities were identified between these two species. This study aims to evaluate the biomechanical properties of different regions of the porcine cornea using atomic force microscopy. Sixteen eyes, enucleated from eight animals, were purchased at a local slaughterhouse. Animals of different breeds, age and weight ranges were used in this study. Fresh eyeballs underwent debridement of the corneal epithelial layer, and subsequently immersed in 25% dextran solution. Measurements of corneal pachymetry in the central, superior, inferior, nasal, and temporal regions were performed at each stage of sample preparation. After 24 hours submerged in dextran solution, the corneas were excised into fragments of approximately 3 x 3 mm, according to the regions described above. These fragments were analysed by atomic force microscope immersed in 25% dextran solution. The values of Young modulus for each fragment were obtained from the elasticity model of Hertz. The storage of samples in dextran solution prevented their excessive hydration, keeping the pachymetry values within normal limits. Both corneal thickness and elastic modulus did not vary among the central, superior, inferior, nasal and temporal regions of the cornea. The thickness and elasticity of the cornea did not differ between right and left eyes. Due to the facility of acquisition and the results obtained, porcine cornea can be used as experimental model for assessment of corneal biomechanical properties.

A radiação ultravioleta pode tanto ser um benefício, como um malefício para o olho humano. Os benefícios são quando é utilizada em procedimentos oftalmológicos para a correção da visão, como nas cirurgias foto-refrativas - UVC - 193 nm; ou para, entre outros tratamentos, impedir a progressão de patologias, como é o caso do crosslinking do colágeno corneano, para ceratocones em estágios inicias que utiliza UVA - 370 nm. Os malefícios são os já amplamente conhecidos pela comunidade científica e populacional, sobre a incidência excessiva de radiação UV nos olhos, causando danos severos ao olho humano. Entretanto, a córnea tem uma proteção natural contra os raios UVA e UVB. Neste trabalho, estudou-se os dois procedimentos oftalmológicos citados a fim de investigar possíveis danos ao olho humano, como a perda da proteção natural da córnea pós cirurgia foto-refrativa, que retira lamelas da córnea; e a quantidade de radiação que adentra o olho humano, durante o crosslinking do colágeno corneano, que utiliza Riboflavina como sintetizador e bloqueador da radiação UVA. Um sistema portátil foi desenvolvido para avaliação da proteção UV e seus danos para o primeiro caso. O protótipo consiste de um sistema de duplo feixe e analisa a transmitância do tecido corneano na faixa de 300-400 nm, e apresenta um fator de correlação r2>0,98. As medidas com remoção de tecido indicaram a importância das camadas da córnea, e a remoção do estroma apresentou uma perda significativa da proteção natural UV, com aumento de 8,2-10,1 pontos percentuais. Já para o crosslinking, que utiliza a combinação riboflavina e UVA, com irradiância de 3 mw/\'CM POT.2\' por 30 minutos foi feito o monitoramento da transmitância UVA durante o tratamento. Foi realizado o protocolo do procedimento atual, ou seja, uma gota de Riboflavina 0,1%, 400mOsm, foi instilada na córnea desepitelizada, a cada 5 minutos (total de 12 gotas). A irradiação UV (365 ± 5 nm, 3 mW/\'CM POT.2\') foi realizada após 30 min de instalação por uma adicional de mais 30 min. A transmitância média da córnea desepitelizada sem Riboflavina foi de 61,6%; após a 1ª instilação de Riboflavina a transmitância foi de 44,9%; após a 6ª gota 22,4%; após a 7ª gota (início da irradiação), 19,5%; após a 8ª gota, 17,3%; após a 9ª, 15,8%; após a 10ª; 14,5%; após a 11ª; 13,5%; e após a 12ª instilação, 12,6%. A transmitância média em termos de energia durante os 30 min de irradiação apresentou uma variação de 0,590 até 0,380 mW/\'CM POT.2\', valores além do limite atualmente aceito para endotélio de córneas de coelhos, que apresenta um nível de segurança citotóxico de 0,36 mW/\'CM POT.2\'. / Ultraviolet radiation can either be a benefit as an harm to the human eye. The benefits are when used in ophthalmic procedures for vision correction, as in the photorefractive surgery - UVC - 193 nm; or to, among other treatments, preventing the progression of diseases, such as the corneal collagen crosslinking, for keratoconus in the early stages - that uses UVA - 370 nm. The harm effects are already widely known by the scientific community and general population, about excessive incidence of UV radiation in the eye, that can cause severe damage to the human eye. However, the cornea has a natural UVA and UVB protection. In this work, we studied the two ophthalmic procedures cited in order to investigate possible damage to the human eye, as the loss of cornea UV natural protection after photorefractive surgery, which removes corneal lamella; and the amount of radiation that penetrates the human eye during the corneal collagen crosslinking, that uses Riboflavin as a synthesizer and UVA radiation blocking. A portable system was developed to evaluate the UV protection and the UV damage for the first case. The prototype consists of a double beam system that analyzes the corneal tissue transmittance in the 300-400 nm range, and presents a correlation factor r2>0.98. Measurements with tissue removal showed the importance of each corneal layer, specially the stroma removal that shows a significant loss of natural UV protection, with an increase of 8.2 to 10.1 percentage points. As for the crosslinking, using riboflavin and UVA irradiance combination, with 3 mw/\'CM POT.2\' for 30 minutes, was performed a monitoring of UVA transmittance during treatment. Current procedure protocol was performed, i.e., one drop of riboflavin 0.1%, 400mOsm, was applied on the naked cornea, every 5 minutes (total of 12 drops). The UV irradiation (365 ± 5 nm, 3 mW/\'CM POT.2\') was performed after 30 min of instillation for an additional 30 min. The average transmittance of the desepithelized cornea without Riboflavin is 61.6%; after the 1st drop of Riboflavin, transmittance is 44.9%; after 6th drop 22.4%; after 7th drop (irradiation starts), 19.5%; after 8th drop; 17.3%; after 9th drop, 15.8%; after 10h drop, 14.5%; after 11th drop, 13.6%; after 12th drop, 12.6%. The average transmittance in terms of energy during the 30 min irradiation procedure fluctuated from 0.590 to 0.380 mW/\'CM POT.2\', beyond the currently accepted rabbit corneal endothelium safety limit for cytotoxic level of 0.360 mW/\'CM POT.2\'.

Um sistema para auxílio à cirurgias oftálmicas foi desenvolvido com o objetivo de se minimizar o astigmatismo induzido devido ao formato irregular da córnea pelo ato de sutura. O sistema projeta 48 pontos de luz no filme lacrimal da córnea, provenientes de LEDs, dispostos num diâmetro precisamente circular. O deslocamento, a dimensão e a deformação da imagem refletida destes pontos luminosos são analisados proporcionando a ceratometria e a circularidade da sutura. O intervalo de medidas do sistema é de 32D - 55D (astigmatismos até 23D podem ser medidos) e um sistema para calibração do sistema foi projetado para manter o sistema calibrado. Esferas de aço de precisão foram submetidas ao sistema e uma correlação de 99% entre as medidas obtidas e os valores dos fabricantes foi obtida. O sistema foi testado em 13 voluntários para avaliação de sua aplicabilidade clínica e comparado a um ceratômetro comercial Topcon OM-4. Os fatores de correlação entre o sistema desenvolvido e o Topcon OM-4, para o astigmatismo, foi de \'R POT.2\' = 0,92, e em relação ao eixo, o fator é \'R POT.2\' = 0,99. O sistema indica que o cirurgião deve obter uma circularidade \'> OU =\' 98% para que astigmatismos acima de 3D não sejam induzidos na sutura. / A system for ophthalmic surgery support has been developed in order to minimize the residual astigmatism due to the induced irregular shape of the cornea by corneal suture. The system projects 48 light spots, from LEDs, displayed in a precise circle at the lachrymal film of the examined cornea. The displacement, the size and deformation of the reflected image of these light spots are analyzed providing the keratometry and the circularity of the suture. Measurements in the range of 32D - 55D (up to 23D of astigmatism are possible to be obtained) and a self-calibration system has been designed in order to keep the system calibrated. Steel precision spheres have been submitted to the system and the results show 99% of correlation with the fabricant\'s nominal values. The system has been tested in 13 persons in order to evaluate its clinical applicability and has been compared to a commercial keratometer Topcon OM-4. The correlation factors are 0,92 for the astigmatism and 0.99 for the associated axis. The system indicates that the surgeon should achieve circularity \'> OR =\' 98% in order to do not induce astigmatisms over 3D.

O objetivo do presente trabalho foi avaliar a influência da aplicação de bevacizumab (Avastin®) sobre a angiogênese corneal. Para tanto ratos Wistar, machos, com idade entre 8 e 10 semanas, pesando 300 a 350g, foram submetidos a cauterização química com nitrato de prata por 10 segundos. Após realização da lesão, cada grupo de 5 animais foi tratado com injeções subconjuntivais de 0,02 ml de bevacizumab (Avastin ®) pela via subconjuntival no momento da lesão, no 3° e 5° dia e submetidos à eutanásia ao 7° dia após cauterização corneal. A rede vascular neoformada foi quantificada após preenchimento do leito vascular com Tinta da China e análise das imagens em sistema computadorizado (Image Pro-Plus®). Para a segunda etapa do experimento, avaliou-se a atividade das metaloproteinases MMP-2 e MMP-9 utilizando-se do mesmo modelo de angiogênese e dos mesmos tempos de tratamento. Transcorridos 7 dias de lesão corneal os animais foram eutanasiados e suas córneas submetidas a zimografia. Os resultados mostraram haver uma inibição da angiogênese quando se compara o grupo controle aos grupos tratados nos diferentes períodos de tempo. Quando a densidade vascular é comparada entre os tempos de aplicação, não se observa diferença estatisticamente significante. Estes resultados em conjunto indicam que o tempo de aplicação não influencia a inibição da angiogênese e que o bevacizumab foi eficiente na redução da formação de vasos quando se compara a densidade vascular do grupo controle. O modelo experimental produziu considerável aumento das metaloproteinases MMP-2 e MMP-9. Houve uma tendência a diminuição da atividade das MMPs quando bevacizumab foi aplicado no momento da lesão e quando foi aplicado ao 3° dia após cauterização. A atividade das MMPs mostrou-se aumentada quando o tratamento foi realizado no 5° dia. Desta forma pode-se concluir que o bevacizumab foi capaz de inibir a angiogênese corneal, independentemente do período de tratamento e ainda que houve uma tendência a redução da atividade das MMPs carecendo, por enquanto, de mais investigações que possam elucidar a interação deste fármaco com a inibição de sua atividade. / The purpose of this study was to evaluate the effects of the use of the subconjunctival injection of bevacizumab (Avastin®) on angiogenesis and metalloproteinases activities in the rat cornea after cauterization. Wistar male rats, aging 8 to 10 weeks, were used. The animals were divided in four groups: control group (GC) that received subconjunctivally 0,02 ml of 0,9% saline solution; group GO that received subconjunctivally 0,02 ml of bevacizumab just after the lesion; group G3 that received bevacizumab at day 3 after lesion and G5 that received bevacizumab at day 5 after lesion. The animals were euthanized at day 7 after lesion. The new formed vessels were quantified after the China Ink perfusion and photographs were obtained and analyzed in computadorized system (Image Pro-Plus®). The activities of metalloproteinases MMP-2 and MMP-9 were evaluated by zimography in a pool of corneas obtained from animals submitted to the same model and treatment schedule. The results showed an inhibition of angiogesenis when the control group were compared with all treated groups. There were no statistic differences when vascular density was compared between the treated groups. These results may indicate that bevacizumab was able to inhibit corneal angiogenesis and that there was no influence of the injection day. This angiogenesis model promoted an increase of matrix metalloproteinases MMP-2 and MMP-9 activity. Zymography also showed a slight reduction in matrix metalloproteinases activity when bevacizumab were administrated at the injury moment and most significant at day 3. At day 5 zymography showed an increase of the activity of these metalloproteinases. Together these results may indicate that the subconjunctival injection of bevacizumab may have a therapeutic potential as an antiangiogenic agent and that matrix metalloproteinases activity decreased, but not at significant levels, demanding more investigations regarding to the interaction of bevacizumab and activity of matrix metalloproteinases.

OBJETIVO: avaliar e correlacionar parâmetros tomográficos de segmento anterior e parâmetros biomecânicos de córnea entre si, com a idade e o gênero de pacientes com olhos normais. MÉTODOS: um estudo clínico de série de casos com intervenção diagnóstica foi realizado, envolvendo um olho selecionado aleatoriamente de 235 pacientes (235 olhos). Os pacientes foram submetidos a exame oftalmológico completo, incluindo avaliação tomográfica (Pentacam) e biomecânica (ORA). Parâmetros avaliados pelo Pentacam: K1, K2, K Front Max , Astig, ISV, IVA, KI, CKI, IHA, IHD, BAD D, BAD Df, BAD Db, BAD Dp, BAD Dt, BAD Dy, ART Max, ART Avg, ART Min, Enh BFS Front 8mm, Enh BFS Back 8mm, Ele F BFS 8mm Apex, Ele F BFS 8mm Thinnest, Ele F BFS 8mm Max 4mm zone, Ele B BFS 8mm Apex, Ele B BFS 8mm Thinnest, Ele B BFS 8mm Max 4mm zone, Ele F BFTE 8mm Apex, Ele F BFTE 8mm Thinnest, Ele F BFTE 8mm 4 mm zone, Ele B BFTE 8mm Apex, Ele B BFTE 8mm Thinnest, Ele B BFTE 8mm Max 4mm zone, RPI Max, RPI Avg, RPI Min, Diff RPI Max Compl, Diff RPI Min Compl, Pachy Min, Pachy Apex, Pachy Pupil, Rel Pachy Min, Asph Q Front 30º, Asph Q Back 30º, Q Asymmetr Frontal Hor 30º, Q Asymmetr Frontal Vert 30º, AC Depth, AC Volume, Ch Angle, Volume, PNS, Densid Avg %. Parâmetros avaliados pelo ORA: IOPg, IOPcc, CH, CRF, KC Score, KC Normal, KC Suspect, KC Mild, KC Moderate, KC Severe, WS, aindex, bindex, p1area, p2area, aspect1, aspect2, uslope1, uslope2, dslope1, dslope2, w1, w2, h1, h2, dive1, dive2 , path1, path2, mslew1, mslew2, slew1, slew2, aplhf, p1area1, p2area1, aspect11, aspect21, uslope11, uslope21, dslope11, dslope21, w11, w21, h11, h21, path11, path21. RESULTADOS: K1, K2, K Max Front, BAD Df, Ele B BFS 8mm Thinnest, Ele B BFTE 8mm Thinnest, CRF e CH apresentaram valores mais altos no sexo feminino, enquanto BAD Db, Enh BFS Front 8mm, AC Depth, AC Volume, Ch Angle, p1area, w2, h1, p1area1, w21 e h11 apresentam valores mais altos no sexo masculino. CKI, BAD Db, Ele F BFS 8mm Apex, Ele F BFS 8mm Thinnest, Ele F BFTE 8mm Apex, Ele F BFTE 8mm Thinnest, Asph Q Back 30º, AC Depth, Ch Angle mostraram forte correlação negativa com a idade. Ele B BFS 8mm Apex, Ele B BFS 8mm Thinnest, Ele B BFTE 8mm Apex, Ele B BFTE 8mm Thinnest mostraram forte correlação positiva com a idade. As correlações mais altas de CH e CRF ocorreram com BAD Dt, Pachy Min, Pachy Apex e Pachy Pupil, ou seja, CH e CRF apresentaram associação positiva com a espessura corneana central. As correlações mais altas da IOPg ocorreram com BAD Dt, ART Max, ART Avg, Pachy Min, Pachy Apex e Pachy Pupil mostrando ser afetada pela espessura corneana. A IOPcc mostrou correlações mais baixas do que as obtidas com a IOPg, sendo esta menos afetada pela espessura corneana. CONCLUSÃO: Os parâmetros tomográficos de segmento anterior (Pentacam) e biomecânicos (ORA) mostraram diversas associações estatisticamente significantes entre si com a idade e com o gênero de pacientes com olhos normais / PURPOSE: to evaluate and to correlate anterior segment tomography parameters and corneal biomechanical parameters between each other, age and gender in patients with healthy eyes. METHODS: a clinical study of case series design with diagnostic intervention was conducted, involving one eye randomly selected from 235 patients (235 eyes). Patients underwent complete ophthalmological examination, including tomographic (Pentacam) and biomechanical (ORA) evaluation. Pentacam parameters assesssed: K1, K2, K Front Max , Astig, ISV, IVA, KI, CKI, IHA, IHD, BAD D, BAD Df, BAD Db, BAD Dp, BAD Dt, BAD Dy, ART Max, ART Avg, ART Min, Enh BFS Front 8mm, Enh BFS Back 8mm, Ele F BFS 8mm Apex, Ele F BFS 8mm Thinnest, Ele F BFS 8mm Max 4mm zone, Ele B BFS 8mm Apex, Ele B BFS 8mm Thinnest, Ele B BFS 8mm Max 4mm zone, Ele F BFTE 8mm Apex, Ele F BFTE 8mm Thinnest, Ele F BFTE 8mm 4 mm zone, Ele B BFTE 8mm Apex, Ele B BFTE 8mm Thinnest, Ele B BFTE 8mm Max 4mm zone, RPI Max, RPI Avg, RPI Min, Diff RPI Max Compl, Diff RPI Min Compl, Pachy Min, Pachy Apex, Pachy Pupil, Rel Pachy Min, Asph Q Front 30º, Asph Q Back 30º, Q Asymmetr Frontal Hor 30º, Q Asymmetr Frontal Vert 30º, AC Depth, AC Volume, Ch Angle, Volume, PNS, Densid Avg %. ORA Parameters assessed: IOPg, IOPcc, CH, CRF, KC Score, KC Normal, KC Suspect, KC Mild, KC Moderate, KC Severe, WS, aindex, bindex, p1area, p2area, aspect1, aspect2, uslope1, uslope2, dslope1, dslope2, w1, w2, h1, h2, dive1, dive2 , path1, path2, mslew1, mslew 2, slew1, slew2, aplhf, p1area1, p2area1, aspect11, aspect21, uslope11, uslope21, dslope11, dslope21, w11, w21, h11, h21, path11, path21. RESULTS: K1, K2, K Max Front, BAD Df, Ele B BFS 8mm Thinnest, Ele B BFTE 8mm Thinnest, CRF and CH showed higher values in females and BAD Db, Enh BFS Front 8mm, AC Depth, AC Volume, Ch Angle, p1area, w2, h1, p1area1, w21 and h11 showed higher values in males. CKI, BAD Db, Ele F BFS 8mm Apex, Ele F BFS 8mm Thinnest, Ele F BFTE 8mm Apex, Ele F BFTE 8mm Thinnest, Asph Q Back 30º, AC Depth, Ch Angle showed strong negative correlation with age. Ele B BFS 8mm Apex, Ele B BFS 8mm Thinnest, Ele B BFTE 8mm Apex, Ele B BFTE 8mm Thinnest showed strong positive correlation with age. The highest correlations of CH and CRF occurred with BAD Dt, Pachy Min, Pachy Apex and Pachy Pupil, i.e. CH and CRF presented positive association with central corneal thickness. The highest correlations of IOPg occurred with BAD Dt, ART Max, ART Avg, Pachy Min, Pachy Apex and Pachy Pupil, showing that it is affected by the thickness of the cornea. IOPcc showed lower correlations than those obtained with IOPg, showing that it is less affected by the thickness of the cornea. CONCLUSION: Anterior segment tomographic parameters (Pentacam) and biomechanical parameters (ORA) showed several statistically significant associations between each other, age and gender in patients with healthy eyes

OBEJTIVOS: Analisar a segurança e eficácia da cirurgia de crosslinking (CXL) de córnea em pacientes com ceratocone em estágios avançados após um seguimento de 4 anos. MÉTODOS: Trata-se de um estudo retrospectivo de pacientes com ceratocone avançado em progressão (Estágio 3 e 4 da classificação de Amsler-Krumeich) que foram submetidos a cirurgia de CXL seguindo o protocolo padrão. Os parâmetros examinados foram acuidade visual com (AVCC) e sem (AVSC) correção, valores ceratométricos (média, plana, curva e apical), paquimetria, e contagem de células endoteliais no préoperatório e após 12, 24 e 48 meses do procedimento. RESULTADOS: Este estudo abrange quarenta olhos de 40 pacientes que foram submetidos a cirurgia de CXL. A média de idade foi 22,5 anos (Intervalo:15 a 37 anos). Tanto a AVSC quanto a AVCC permaneceram estáveis durante o período de seguimento, sem mudanças estatisticamente significativas. Apesar de todos os valores ceratométricos sofrerem uma leve diminuição, apenas a ceratometria apical atingiu uma mudança com significado estatístico (P=0,037) após 4 anos de seguimento. Uma redução significativa da espessura corneana foi também observada (paquimetria ultrassônica era de 388 ± 49 e passou para 379 ± 48 ?m, P < 0,0001; paquimetria através de tomografia de imagem em fenda era de 362 ± 48 e foi para 353 ± 51 um, P < 0,0001); embora essa diferença não seja clinicamente significativa. A contagem de células endoteliais não sofreu alterações significativas durante o seguimento. A taxa de falha do tratamento foi de 5% (dois pacientes) durante o seguimento. CONCLUSA?O: A cirurgia de CXL corneano em pacientes com ceratocone avançado se mostrou segura e capaz de manter os parâmetros visuais e topográficos pelo menos durante 4 anos / PURPOSE: To analyze the safety and efficacy of standard corneal collagen crosslinking (CXL) in advanced cases of progressive keratoconus (KC) after four years of follow-up. METHODS: A retrospective case series of patients with advanced progressive KC (stage 3 and 4 of Amsler-Krumeich classification) underwent standard CXL treatment. The parameters examined were changes in uncorrected visual acuity (UDVA), corrected visual acuity (CDVA), keratometry values (mean K, flattest K, steepest K, and apical K), pachymetry, and endothelial cell count at the baseline and at 12-, 24- and 48-months postoperatively. RESULTS: Forty eyes of 40 patients were enrolled into the study. The mean patient age was 22.5 years (range: 15 to 37 years). Both mean UCVA and CDVA remained stable during the time points; no statistically significant change was noted. Although a slightly reduction was observed in all keratometric readings, a statistically significant reduction was only reached in the apical K (p=0.037) at four years after CXL. A significant reduction in the pachymetry was also found (from 388±49 to 379±48 um, P < 0,0001 and from 362±48 to 353±51 um, P < 0,0001, ultrasonic and slit-scanning readings, respectively) ; however this change is not likely clinically meaningful. Endothelial cell count was not significantly modified at the end of the study. Treatment failure or progression was noted in two patients (5%) over the followup period. CONCLUSION: Standard CXL treatment seems to be safe and able to stabilize both visual acuity and topographic parameters at four-year follow-up in advanced keratoconic eyes