Current concepts in vitreomacular traction syndrome.

PURPOSE OF REVIEW: As Reese first described the vitreomacular traction (VMT) syndrome in 1970, the knowledge base about the disease has been changing over time due to the advent of the high-definition optical coherence tomography (HD-OCT). The aim of this article was to present the current information on the pathophysiology, anatomic macular abnormality associations, treatments, and new concepts in VMT syndrome. RECENT FINDINGS: HD-OCT has provided unprecedented visualization of the vitreomacular interface, which has led to better comprehension of the VMT syndrome. The technologic advances also emphasized the need to review the basis of the VMT syndrome and define as yet unsettled and often confusing concepts. SUMMARY: The recognition of the role of VMT in a variety of macular conditions is imperative for proper diagnosis and appropriate management of these diseases.

Impaired glucose tolerance plus hyperlipidaemia induced by diet promotes retina microaneurysms in New Zealand rabbits.

UNLABELLED: With the increasing prevalence of diabetes mellitus and metabolic syndrome worldwide, experimental models are required to better understand the pathophysiology and therapeutic approaches to preserve pancreatic beta cells, attenuate atherosclerosis and protect target organs. The aims of this study were to develop an experimental model of impaired glucose tolerance combined with hypercholesterolaemia induced by diet and assess metabolic alterations and target organ lesions. New Zealand male rabbits were fed high-fat/high-sucrose (10/40%) and cholesterol-enriched diet for 24 weeks, when they were sacrificed. Biochemistry, fundus photographs with fluorescein angiography and pathological analyses were performed. Cholesterol-fed and normal animals of same age were compared. RESULTS: The animals with diet-induced impaired glucose tolerance combined with hypercholesterolaemia gained weight, increased blood glucose, total cholesterol, LDL-C and triglycerides and decreased HDL-C (P < 0.05 vs. baseline). Fructosamine levels and the homeostasis model assessment of insulin resistance (HOMA-IR) index were increased, while there was a reduction in the HOMA-ß (P < 0.05 for all vs. baseline). Histomorphologic findings of this model were aortic atherosclerosis, hepatic steatofibrosis and glomerular macrophage infiltration. Early clinical features of diabetic retinopathy with hyperfluorescent dots consistent with presence of retina microaneurysms were seen since week 12, progressing up to the end of the experiment (P < 0.0005 vs. baseline and 12 weeks). Our model reproduced several metabolic characteristics of human diabetes mellitus and promoted early signs of retinopathy. This non-expensive model is suitable for studying mechanistic pathways and allowing novel strategic approaches.

Retinal and ocular toxicity in ocular application of drugs and chemicals--part I: animal models and toxicity assays.

AIMS: Experimental retinal research has gained great importance due to the ophthalmic pharmacotherapy era. An increasing number of drugs are constantly released into the market for the treatment of retinal diseases. In this review, animal species, animal models and toxicity assays in retinal research are discussed. METHODS: An extensive search of the literature was performed to review various aspects of the methods of investigation of drug toxicity. The different types of animal species, as well as single animal models available for the evaluation of safety and efficacy of retinal pharmacotherapy, were identified. In addition, a large variety of reported laboratory techniques were critically examined. RESULTS: In vitro studies are the first-line experiments for the development of a new drug for retinal diseases, using retinal pigment epithelial cells and other cell lines. The next step involves in vivo animal studies where nonhuman primates are considered the gold standard. However, cost and legal issues make their use difficult. Mice and rats provide genetically controlled models for investigations. Pigs, dogs and cats represent good large-size animal models, while rabbits are one of the most used species for retinal toxicity evaluations. Various laboratory methods were identified, including light microscopy, electron microscopy, electroretinography and new emerging methods, such as optical coherence tomography and scanning laser ophthalmoscopy for experimental purposes. CONCLUSIONS: A great number of animal species and models are available that simulate retinal diseases and provide experimental data for further human use. Work with animal models should include properly designed toxicity assays to obtain reliable results for safety and efficacy.

Preclinical investigation of the retinal biocompatibility of six novel vital dyes for chromovitrectomy.

PURPOSE: To investigate the retinal biocompatibility of six novel vital dyes for chromovitrectomy. METHODS: An amount of 0.05 mL of 0.5% and 0.05% light green (LG), fast green (FG), Evans blue (EB), brilliant blue (BriB), bromophenol blue (BroB), or indigo carmine (IC) was injected intravitreally in the right eye, whereas in the left eye balanced salt solution was applied for control in rabbits' eyes. Clinical examination, fluorescein angiography, histology with light microscopy, and transmission electron microscopy were performed after 1 and 7 days. Retinal cell layers were evaluated for morphologic alterations and number of cells. The electroretinographic changes were assessed at baseline, 24 hours and 7 days. RESULTS: Fluorescein angiography disclosed hypofluorescent spots only in the 0.5% EB group. Light microscopy and transmission electron microscopy disclosed slight focal morphologic changes in eyes exposed to 0.05% IC, FG, BriB, similar to the control at 1 and 7 days. In the lower dose groups, EB, LG, and BroB caused substantial retinal alterations by light microscopy. At the higher dose, BroB and EB produced diffuse cellular edema and vacuolization within the ganglion cells, bipolar cells, and photoreceptors. FG and IC at 0.5% caused slight retinal alterations similar to balanced salt solution injection. LG at 0.5% caused diffuse vacuolization of bipolar cells after 1 and 7 days. Injection of 0.5% EB caused a significant decrease in neuroretinal cell counts in comparison to control eyes in the 7-day examination (P < 0.05). Electroretinography revealed intermittent prolonged latency and decreased amplitude in eyes injected with 0.5% EB, LG, BriB, and BroB, while at the lower dose, only LG and EB induced few functional changes. CONCLUSION: The progressive order of retinal biocompatibility, from safest to most toxic, was IC, FG, BriB, BroB, LG, EB.

Current concepts of trypan blue in chromovitrectomy.

Trypan blue (TB) is a blue vital dye with fine color properties to stain the anterior lens capsule and thereby may facilitate capsulorrhexis during cataract surgery. In addition, the blue stain may assist in the visualization of various preretinal membranes and tissues during vitreoretinal surgery in a procedure also called chromovitrectomy. TB has demonstrated great binding affinity for the glial epiretinal membranes, although it remains yet to be determined in which circumstances the dye may color the vitreous and internal limiting membrane. Most studies suggest that 0.06% TB does not pose harm to the retina, but at higher concentrations further investigation is necessary. In this paper, various aspects of the application of TB for chromovitrectomy are discussed including laboratory investigations, surgical technique and clinical outcomes.

Higher-order aberrations of age-related cataract.

PURPOSE: To analyze higher-order aberrations induced by different types of lenticular opacities. SETTING: Federal University of São Paulo, São Paulo, Brazil. METHODS: One hundred thirty-eyes of 65 patients with bilateral cataract, classified according to the Lens Opacities Classification System III (LOCS III), had complete ophthalmic examinations, corneal topography (EyeSys Technologies), and wavefront analysis (LADARWave, Alcon Laboratories). Patients with cataracts that could not be measured by a Hartmann-Shack sensor or those with coexisting ocular disease were excluded. Higher-order aberrations were compared between the nuclear, cortical, and posterior subcapsular groups for statistical significance. RESULTS: One hundred five eyes of 65 patients were assessed. Twenty-eight eyes (23.33%) had predominantly nuclear opacification (NO1-NO6 and C1-2), and 13 (10.83%) had mainly cortical opacification (C1-4). Sixty-four eyes (65.83%) had a mixed pattern of LOCS III classification, which hindered the establishment of a correlation between the aberrometry and cataract type. Eighteen eyes that presented with dense posterior subcapsular cataract (P4-5) and 7 eyes with cortical C5 LOCS III classification were excluded. In eyes with nuclear opacification, the mean spherical aberration with a 6.0 mm pupil was 0.45 microm +/- 0.17 (SD) and the mean coma was 0.29 +/- 0.13 microm. In eyes with predominantly cortical cataract, the mean spherical aberration was 0.12 +/- 0.10 microm and the mean coma was 0.49 +/- 0.23 microm. The cortical cataract group had statistically significantly higher coma than the other groups (P<.001). The nuclear cataract group had statistically significantly higher spherical aberrations than the other groups (P<.001). CONCLUSIONS: Different types of early lenticular opacities induced different wavefront aberration profiles. Coma predominated in the cortical cataract group, and spherical aberration predominated in the nuclear cataract group.

Long-term results of photorefractive keratectomy for myopia and myopic astigmatism.

PURPOSE: To assess the long-term refractive outcomes of photorefractive keratectomy in myopia and myopic astigmatism. METHODS: A retrospective study of 120 photorefractive keratectomy operated eyes with at least four-year follow-up (maximum of 96 months, mean follow-up 55 months). We divided patients into group 1 (G1) spherical equivalent (SE) up to -4.00 diopters (D) and group 2 (G2) SE >-4.00 D. The Summit Apex Plus excimer laser was used for ablation. All eyes were analyzed in terms of uncorrected and best spectacle corrected visual acuity (UCVA/BSCVA) and cycloplegic refraction. Data were analyzed using the Refractive Surgery Consultant Elite database software. RESULTS: G1 with 85 eyes (49 patients) presented mean SE -2.42 D and G2 with 35 eyes (22 patients) and mean SE of -4.45 D. Ninety-four percent of eyes in G1 and 82.9% of G2 were within +/-1.00 D of emmetropia at 4 years. The UCVA was 20/30 or better in 82.0% of G1 eyes and 77.0% of G2 in the last postoperative follow-up. No patient lost more than one line in G2 compared to 13.0% in G1. Eyes that gained one or more lines after 4-year follow-up were 11.9% G1 and 2.9% in G2, respectively. A statistically significant positive correlation was found between achieved versus attempted refractive correction in both groups (r=0.925, p<0.0005). CONCLUSIONS: Photorefractive keratectomy was a safe and stable surgical procedure to correct myopic refractive errors, with no significant change in mean postoperative spherical equivalent refraction in the long-term follow-up.

Wavefront analysis and contrast sensitivity of aspheric and spherical intraocular lenses: a randomized prospective study.

PURPOSE: To compare visual performance, total and high order wavefront aberrations (coma, spherical aberration, and other terms), and contrast sensitivity in 120 eyes implanted with one monofocal aspheric intraocular lens (IOL) and two spherical IOLs. DESIGN: Randomized prospective study. METHODS: Sixty patients were randomized to receive three IOL types: Alcon AcrySofIQ (40 eyes), AcrySofNatural (40 eyes), and advanced medical optic (AMO)Sensar (40 eyes). Complete ophthalmologic examination including uncorrected visual acuity (UCVA), best-spectacle corrected visual acuity (BSCVA), corneal topography, and wavefront analysis were performed preoperatively, 30 days, and 90 days postoperatively. Pelli-Robson chart test and functional acuity contrast testing (FACT-Optec6500) were performed approximately 50 days after surgery. Statistical analyses were performed using analysis chi(2), analysis of variance (ANOVA), and multiple comparisons Tukey test. RESULTS: After 90 days, all eyes had postoperative BSCVA > or =20/32. The AcrySofIQ IOL showed statistically significant less induction of spherical aberration (P < .001) when compared with the AMOSensar and the AcrySofNatural IOLs. The AMOSensar presented significantly less spherical aberration then the AcrySofNatural (P < .05). The AcrySofIQ also had lower values of total and high-order aberration (HOA) (P < .05) when compared with the AMOSensar and the AcrySofNatural. The mean values of trefoil 9, coma, and HOA root mean square (RMS) decreased between one and three months (P < .001, P < .001, P = .023, P < .001, respectively) in all groups. Mean Pelli-Robson contrast sensitivity values in photopic condition were similar between the groups. The AcrySofIQ showed better results in 3cpd spatial frequency in mesopic condition using FACT-Optec 6500 (P = .008), although there were no statistical differences in photopic and mesopic with glare conditions.

Nonsteroidal Anti-Inflammatory Drugs in the Treatment of Retinal Diseases.

Nonsteroidal anti-inflammatory drugs (NSAIDs) are an important class of drugs in medicine and ophthalmology. Several NSAIDs have been commercially available for many years: diclofenac, flurbiprofen, indomethacin, ketorolac and suprofen. The purpose of this chapter is to review the clinical use of earlier and newer pharmacologic agents of the NSAID class. NSAIDs may have a modulating effect on ocular inflammation and pain through the prevention of prostaglandin synthesis via cyclooxygenase inhibition. Newer-generation NSAIDs have emerged in recent years for the treatment of ocular pain and inflammation. Nepafenac ophthalmic suspension 0.1% is a new topical NSAID prodrug that has been approved by the Food and Drug Administration for the treatment of pain and inflammation after cataract surgery. Preliminary data suggest nepafenac may also provide unique efficacy in the posterior segment, since its corneal permeability characteristics are superior to those of other NSAIDs. Nevanac, diclofenac, ketorolac and bromfenac are some notable NSAID candidates which should be investigated intravitreally or topically for retinal pharmacotherapy. In addition, for intraocular surgery, NSAIDs can help to prevent intraoperative miosis, reduce ocular pain, decrease postoperative inflammation and prevent cystoid macular edema. Retinal, choroidal and vitreous diseases may be the target of future nepafenac studies, either as monotherapy or as combination treatments.

Vitreomacular traction syndrome: postoperative functional and anatomic outcomes.

BACKGROUND AND OBJECTIVE: To analyze a variety of vitreomacular traction (VMT) morphologies to establish a major classification that better reflects the preoperative predictive factors of postoperative visual and anatomic outcomes. PATIENTS AND METHODS: Thirty-six eyes submitted to vitrectomy surgery were categorized with a VMT pattern (V- or J-shaped) and diameter (focal < 1,500 µm or broad > 1,500 µm) based on optical coherence tomography. RESULTS: The researchers compared different classifications of VMT. Despite similar postoperative best corrected visual acuity (BCVA) values (P = .393), cases with focal VMT had greater visual improvement (P = .027) because the preoperative BCVA was significantly lower in the focal group (P = .007). However, the BCVA improvements did not differ between the groups regarding the classic VMT morphologic patterns (P = .235). CONCLUSION: Postoperative outcomes and macular disorders are closely related to VMT size. The adhesion diameter (focal or broad VMT) and not the classic VMT morphologic pattern (V- or J-shaped) may better predict the postoperative anatomic and functional outcomes.

Vitreomacular traction syndrome.

The advent of new technologies such as high definition optical coherence tomography (OCT) has not only provided unprecedented imaging capabilities, but also raised the need to define concepts not yet settled and often confusing such as the vitreomacular traction (VMT) syndrome. While technological advances drive us into the future by clarifying the pathophysiology of many diseases and enabling novel therapeutic options, it is at the same time necessary to review basic disease concepts in addition to definitions and classifications. VMT syndrome is implicated in the pathophysiology of a number of macular disorders, translating into a variety of anatomical and functional consequences underscoring the complexity of the condition. These macular changes are closely related to the VMT configuration and have led to proposing classification of this syndrome based on OCT findings. The size and severity of the remaining vitreomacular attachment may define the specific maculopathy. Focal VMT usually leads to macular hole formation, tractional cystoid macular edema and foveal retinal detachment, while broad VMT is associated with epiretinal membranes, diffuse retinal thickening and impaired foveal depression recovery. Despite similar postoperative visual acuity (VA) in focal and broad VMT subgroups, visual improvement is greater with focal VMT because preoperative VA is frequently lower. Surgical procedures are effective to relieve VMT and improve VA in most eyes; outcomes vary with VMT morphology and the duration of symptoms.

Macular hole: 10 and 20-MHz ultrasound and spectral-domain optical coherence tomography.

PURPOSE: Optical coherence tomography (OCT) is valuable for macula evaluation. However, as this technique relies on light energy it cannot be performed in the presence of opaque media. In such cases, the ultrasound (US) may predict some macular features. The aim of this study was to characterize images obtained by ultrasound with 10 and 20-MHz transducers comparing to OCT, as well as to analyze the relationship between the vitreous and retina in eyes with macular hole (MH). METHODS: 29 eyes of 22 patients with biomicroscopic evidence of MH at different stages were included. All patients were evaluated using ultrasonography with 10 and 20-MHz transducers and OCT. RESULTS: OCT identified signs of MH in 25 of 29 eyes. The remaining 4 cases not identified by US were pseudoholes caused by epiretinal membranes. In MH stages I (2 eyes) and II (1 eye), both transducers were not useful to analyze the macular thickening, but suggestive findings as macular irregularity, operculum or partial posterior vitreous detachment (PVD) were highlighted. In stages III (14 eyes) and IV (5 eyes), both transducers identified the double hump irregularity and thickening. US could measure the macular thickness and other suggestive findings for MH: operculum, vitreomacular traction and partial or complete PVD. In cases of pseudoholes, US identified irregularities macular contour and a discrete depression. CONCLUSION: 10-MHz US was useful for an overall assessment of the vitreous body as well as its relationship to the retina. The 20-MHz transducer allowed valuable information on the vitreomacular interface and macular contour. OCT provides superior quality for fine morphological study of macular area, except in cases of opaque media. In these cases, and even if OCT is not available, the combined US study is able to provide a valid evaluation of the macular area improving therapeutic approach.

Wavefront-guided refractive surgery results of training-surgeons.

PURPOSE: To assess clinical outcomes and changes on higher-order aberrations (HOA) after wavefront-guided laser in situ keratomileusis (LASIK) and photorefractive keratectomy (PRK) for correction of myopia and myopic astigmatism performed by training-surgeons. METHODS: One hundred and seventy patients had customized LASIK (207 eyes) and PRK (103 eyes) performed by surgeons in-training using the LADARVision 4000 (Alcon, Fort Worth, TX). Preoperative and 1, 3, 6 and 12 months postoperative data of spherical equivalent (SE), best spectacle-corrected visual acuity (BSCVA) and uncorrected visual acuity (UCVA) were analysed. Wavefront changes were determined using the LADARWave Hartmann-Shack wavefront aberrometer and the pupil size was scaled for 6.5 mm. RESULTS: The mean SE in the LASIK group was -3.04 ±1.07 D and in the PRK group was -1.60 ± 0.59 D. At 1-year follow-up, (80.6%) (LASIK) and (66.7%) (PRK) were within ± 0.50 D of the intended refraction. The UCVA was 20/20 or better in (58.1%) (LASIK) and (66.7%) (PRK) of the operated eyes. A statistically significant positive correlation was found between achieved versus attempted refractive correction in both groups: LASIK (r=0.975, P<0.0005) and PRK (r=0.943, P<0.005). The higher-order aberrations (HO) RMS and coma did not changed significantly in the PRK group between preoperative and 1-year follow-up. In the LASIK group the HO RMS and coma changed between preoperative and 1-month postoperative but remained statistically unchanged during 1-year follow-up. The spherical aberration showed statistically significant changes in both groups. CONCLUSIONS: Wavefront-guided LASIK and photorefractive keratectomy performed by training-surgeons were found to be similarly effective, predictable and stable.

The use of vital dyes in ocular surgery.

Vital dyes have advanced diagnosis and surgical technique in various specialties, including oncology, gastroenterology, and ophthalmology. In ocular surgery vital dyes are widely used in cataract and vitreoretinal surgery. Worldwide, intra-operative use of trypan blue during cataract surgery has enhanced visualization of the anterior capsule during capsulorrhexis, and patent blue has been recently licensed in Europe for cataract surgery. For chromovitrectomy, the vital dyes indocyanine green, infracyanine green, and brilliant blue stain the internal limiting membrane, and trypan blue and triamcinolone acetonide help visualize epiretinal membranes and vitreous, respectively. Intra-operative vital dyes are finding uses in corneal, glaucoma, orbit, strabismus, and conjunctival surgery. We provide a summary of current knowledge of the use of vital dyes in ocular surgery. We review the properties of dyes, techniques of application, indications, and complications in ocular surgery. Vital dyes represent an expanding area of research, and novel dyes deserve further investigation.

Impending central retinal vein occlusion associated with cilioretinal artery obstruction.

We report a case of a patient with an impending central retinal vein occlusion (CRVO) with cilioretinal artery obstruction, which may help to understand the nature of the retinal hemodynamic changes associated with CRVO which shows direct evidence of arterial vasospasm, suggesting an increased contractility of retinal arteries. The clinical course, with initial retinal whitening along a cilioretinal artery followed by signs of venous stasis, seems to confirm the pathogenesis hypothesis concerning a primary arterial affection due to arterial vasospasm.

Macular hole: 10 and 20-MHz ultrasound and spectral-domain optical coherence tomography / Buraco macular: ultrassonografia de 10 e 20 MHz e tomografia óptica de domínio espectral

PURPOSE: Optical coherence tomography (OCT) is valuable for macula evaluation. However, as this technique relies on light energy it cannot be performed in the presence of opaque media. In such cases, the ultrasound (US) may predict some macular features. The aim of this study was to characterize images obtained by ultrasound with 10 and 20-MHz transducers comparing to OCT, as well as to analyze the relationship between the vitreous and retina in eyes with macular hole (MH). METHODS: 29 eyes of 22 patients with biomicroscopic evidence of MH at different stages were included. All patients were evaluated using ultrasonography with 10 and 20-MHz transducers and OCT. RESULTS: OCT identified signs of MH in 25 of 29 eyes. The remaining 4 cases not identified by US were pseudoholes caused by epiretinal membranes. In MH stages I (2 eyes) and II (1 eye), both transducers were not useful to analyze the macular thickening, but suggestive findings as macular irregularity, operculum or partial posterior vitreous detachment (PVD) were highlighted. In stages III (14 eyes) and IV (5 eyes), both transducers identified the double hump irregularity and thickening. US could measure the macular thickness and other suggestive findings for MH: operculum, vitreomacular traction and partial or complete PVD. In cases of pseudoholes, US identified irregularities macular contour and a discrete depression. CONCLUSION: 10-MHz US was useful for an overall assessment of the vitreous body as well as its relationship to the retina. The 20-MHz transducer allowed valuable information on the vitreomacular interface and macular contour. OCT provides superior quality for fine morphological study of macular area, except in cases of opaque media. In these cases, and even if OCT is not available, the combined US study is able to provide a valid evaluation of the macular area improving therapeutic approach.

OBJETIVO: A tomografia de coerência óptica (OCT) é um método diagnóstico valioso para estudo da mácula. Entretanto, por se basear na energia luminosa, não pode ser realizada quando existe opacidade de meios. Nesses casos, o ultrassom (US) pode predizer algumas características maculares. Este estudo teve como objetivos caracterizar imagens obtidas por US com transdutores de 10 e 20-MHz comparadas ao OCT, assim como analisar a relação vitreorretiniana em olhos com buraco macular (BM). MÉTODOS: Vinte e nove olhos de 22 pacientes com evidência biomicroscópica de BM em diferentes estágios foram incluídos. Todos os pacientes foram avaliados com ultrassonografia utilizando transdutores de 10 e 20-MHz e OCT de domínio espectral. RESULTADOS: OCT diagnosticou BM em 25 dentre 29 olhos estudados. Os 4 casos não identificados por US eram pseudoburacos decorrentes de membrana epirretiniana. Nos BM estágios I (2 olhos) e II (1 olho), ambos transdutores não foram úteis para analisar o espessamento macular, mas foram identificados sinais sugestivos como irregularidade macular, opérculo ou descolamento parcial do vítreo posterior (DVP). Nos estágios III (14 olhos) e IV (5 olhos), ambos transdutores identificaram irregularidade, dupla corcova e espessamento macular. O US foi capaz de medir a espessura macular e identificar outros indícios de BM, como opérculo, tração vitreorretiniana e DVP. Em pseudoburacos, o US identificou irregularidades no contorno macular e discreta depressão. CONCLUSÃO: US de 10-MHz foi útil para uma avaliação global do corpo vítreo e sua relação à retina. O US de 20-MHz forneceu informações importantes sobre a junção vitreorretiniana e contorno macular. OCT fornece qualidade superior para estudo morfológico da região macular, exceto em casos de opacidade de meios. Nesses casos, ou quando o exame tomográfico não for disponível, o estudo ultrassonográfico de 10 e 20-MHz é capaz de proporcionar análise válida da região macular e auxiliar na abordagem terapêutica.

Wavefront-guided refractive surgery results of training-surgeons / Resultados das cirurgias refrativas guiadas por frentes de ondas de cirurgiões em treinamento

PURPOSE: To assess clinical outcomes and changes on higher-order aberrations (HOA) after wavefront-guided laser in situ keratomileusis (LASIK) and photorefractive keratectomy (PRK) for correction of myopia and myopic astigmatism performed by training-surgeons. METHODS: One hundred and seventy patients had customized LASIK (207 eyes) and PRK (103 eyes) performed by surgeons in-training using the LADARVision 4000 (Alcon, Fort Worth, TX). Preoperative and 1, 3, 6 and 12 months postoperative data of spherical equivalent (SE), best spectacle-corrected visual acuity (BSCVA) and uncorrected visual acuity (UCVA) were analysed. Wavefront changes were determined using the LADARWave Hartmann-Shack wavefront aberrometer and the pupil size was scaled for 6.5 mm. RESULTS: The mean SE in the LASIK group was -3.04 ±1.07 D and in the PRK group was -1.60 ± 0.59 D. At 1-year follow-up, (80.6 percent) (LASIK) and (66.7 percent) (PRK) were within ± 0.50 D of the intended refraction. The UCVA was 20/20 or better in (58.1 percent) (LASIK) and (66.7 percent) (PRK) of the operated eyes. A statistically significant positive correlation was found between achieved versus attempted refractive correction in both groups: LASIK (r=0.975, P<0.0005) and PRK (r=0.943, P<0.005). The higher-order aberrations (HO) RMS and coma did not changed signicantly in the PRK group between preoperative and 1-year follow-up. In the LASIK group the HO RMS and coma changed between preoperative and 1-month postoperative but remained statistically unchanged during 1-year follow-up. The spherical aberration showed statistically significant changes in both groups. CONCLUSIONS: Wavefront-guided LASIK and photorefractive keratectomy performed by training-surgeons were found to be similarly effective, predictable and stable.

OBJETIVO: Avaliar os resultados clínicos e mudanças nas aberrações de alta-ordem (HOA), após ceratomileuse assistida por excimer laser in situ (LASIK) e ceratectomia fotorrefrativa (PRK) guiados por frentes de onda para correção da miopia e astigmatismo miópico realizada por cirurgiões em treinamento. MÉTODOS: Estudo prospectivo de 170 pacientes submetidos a LASIK personalizado (207 olhos) e PRK (103 olhos) realizados por cirurgiões em treinamento utilizando o LADARVision 4000 (Alcon, Fort Worth, TX). Dados do equivalente esférico (SE), melhor acuidade visual corrigida (BSCVA) e acuidade visual não corrigida (UCVA) foram analisados no pré-operatório e com 1, 3, 6 e 12 meses de pós-operatório. As alterações de frentes de onda foram determinadas usando o aberrômetro Hartmann-Shack (LADARWave)e o tamanho da pupila foi determinado para 6,5 mm. RESULTADOS: A média do SE no grupo de LASIK foi -3,04 ± 1,07 D e no grupo de PRK foi -1,60 ± 0,59 D. No seguimento de um ano, (80,6 por cento) (LASIK) e (66,7 por cento) (PRK) estavam dentro de ± 0,50 D de equivalente esférico. A UCVA foi de 20/20, ou melhor, em (58,1 por cento) (LASIK) e (66,7 por cento) (PRK) dos olhos operados. Foi encontrada correlação positiva estatisticamente significante entre correção refrativa alcançada versus pretendida em ambos os grupos: LASIK (r=0,975, P<0,0005) e PRK (r=0,943, P<0,005). O HO RMS e coma não alteraram significantemente no grupo PRK entre pré-operatório e após um ano de seguimento. No grupo de LASIK o HO RMS e o coma alteraram entre pré-operatório e 1º mês de pós-operatório, mas permaneceram estatisticamente inalterados durante um ano de seguimento. Houve alterações estatisticamente significantes da aberração esférica em ambos os grupos. CONCLUSÕES: O LASIK e o PRK guiados por frentes de onda, realizados por cirurgiões em treinamento, mostraram ser similarmente eficazes, previsíveis e estáveis.

Long-term results of photorefractive keratectomy for myopia and myopic astigmatism

PURPOSE: To assess the long-term refractive outcomes of photorefractive keratectomy in myopia and myopic astigmatism. METHODS: A retrospective study of 120 photorefractive keratectomy operated eyes with at least four-year follow-up (maximum of 96 months, mean follow-up 55 months). We divided patients into group 1 (G1) spherical equivalent (SE) up to -4.00 diopters (D) and group 2 (G2) SE >-4.00 D. The Summit Apex Plus® excimer laser was used for ablation. All eyes were analyzed in terms of uncorrected and best spectacle corrected visual acuity (UCVA/BSCVA) and cycloplegic refraction. Data were analyzed using the Refractive Surgery Consultant Elite database software. RESULTS: G1 with 85 eyes (49 patients) presented mean SE -2.42 D and G2 with 35 eyes (22 patients) and mean SE of -4.45 D. Ninety-four percent of eyes in G1 and 82.9 percent of G2 were within ±1.00 D of emmetropia at 4 years. The UCVA was 20/30 or better in 82.0 percent of G1 eyes and 77.0 percent of G2 in the last postoperative follow-up. No patient lost more than one line in G2 compared to 13.0 percent in G1. Eyes that gained one or more lines after 4-year follow-up were 11.9 percent G1 and 2.9 percent in G2, respectively. A statistically significant positive correlation was found between achieved versus attempted refractive correction in both groups (r=0.925, p<0.0005). CONCLUSIONS: Photorefractive keratectomy was a safe and stable surgical procedure to correct myopic refractive errors, with no significant change in mean postoperative spherical equivalent refraction in the long-term follow-up.

OBJETIVO: Relatar os resultados a longo prazo da cirurgia de ceratectomia fotorefrativa em miopia e astigmatismo miópico. MÉTODOS: Estudo retrospectivo de120 olhos operados de ceratectomia fotorefrativa com um mínimo intervalo de 4 anos de seguimento pós-operatório (máximo de 96 meses e seguimento médio de 55 meses). Dividimos em grupo 1 (G1) com equivalente esférico (SE) até -4.00 dioptrias (D) e grupo 2(G2) SE > -4.00 D. O excimer laser Summit Apex Plus® foi usado na ablação. Foram obtidas acuidade visual não corrigida (UCVA) e melhor acuidade visual corrigida (BSCVA) e refração sob cicloplegia. Os dados foram analisados utilizando o programa Refractive Surgery Consultant Elite database®. RESULTADOS: G1 com 85 olhos (49 pacientes) apresentaram SE médio de -2.42 D e o G2 com 35 olhos (22 pacientes) e SE médio de -4,45 D. No G1 94 por cento e 82,9 por cento no G2 estavam entre ±1,00D de emetropia em 4 anos. A acuidade visual não corrigida foi de 20/30, ou melhor, em 82,0 por cento nos olhos de G1 e 77,0 por cento de G2 no último seguimento. Nenhum paciente perdeu mais do que uma linha de visão no G2 comparado com 13,0 por cento em G1. Ganho de linha de visão após 4 anos foi respectivamente 11,9 por cento em G1 e 2,9 por cento em G2. Correlação positiva estatisticamente significante foi encontrada entre correção refrativa programada versus atingida em ambos os grupos (r=0,925, p<0,0005). CONCLUSÃO: Ceratectomia fotorefrativa foi um procedimento cirúrgico seguro e estável para corrigir erros refracionais miópicos, sem mudança significativa no equivalente esférico médio da refração pós-operatória em longo prazo.

Adesivo biológico de fibrina na mioescleropexia posterior em coelhos: estudo experimental / Fibrin biological adhesive for posterior mioscleral fixation of superior rectus muscles: an experimental study in rabbits

OBJETIVOS: 1. Verificar a capacidade de cola do adesivo biológico de fibrina quando utilizado para reduzir o arco de contato do músculo reto superior com a esclera de coelhos. 2. Comparar a redução da função do músculo reto superior tratado com a função do músculo reto superior contralateral, utilizado como controle. MÉTODOS: A amostra foi constituída por 30 coelhos, 60 olhos. Em cada coelho, realizou-se mioescleropexia posterior com adesivo biológico em um dos olhos (30 olhos), enquanto o outro serviu como controle (30 olhos). Todos os animais foram sacrificados após 60 dias pós-operatórios. Avaliaram-se a hipofunção muscular e o tamanho da aderência mioescleral produzida imediatamente pela cirurgia e após 60 dias. RESULTADOS: O coágulo de fibrina formou-se imediatamente à sua aplicação no músculo, e as fibras musculares apresentaram-se aderidas em poucos segundos à esclera. Todos os olhos operados com adesivo bio-lógico de fibrina demonstraram hipofunção muscular após 60 dias, quando comparada ao músculo contralateral. O tamanho do coágulo formado inicialmente, relacionado às medidas obtidas após 60 dias, demonstrou uma porcentagem de redução de 28,48 por cento e uma correlação ascendente e positiva (r=0,367204), porém fraca, elucidando a existência de múltiplas variáveis influenciando nessa redução. Não houve sinais de hiperemia, secreção conjuntival, ou qualquer outra complicação atribuída à cirurgia, ao final de 60 dias. CONCLUSAO: O adesivo biológico de fibrina provoca adesão músculo-escleral, encurtando o arco de contato, ocasionando a hipofunção desejada. A aplicação do adesivo facilita a mioescleropexia posterior, evitando a possibilidade de perfuração ocular.

Hipertensäo e retinopatia hipertensiva / Hypertension and hypertensive retinopathy

Objetivo: Avaliar a prevalência de retinopatia hipertensiva (RH) em pacientes hipertensos (controlados e näo controlados) e normotensos na populaçäo acima dos 40 anos do município de Piraquara. Correlacionar os casos de alteraçäo retiniana com o sexo, a raça e a idade do paciente. Métodos: Durante 1998 e 2000, foram examinados no Projeto Glaucoma da Universidade Federal do Paraná 1.954 pacientes. Destes, excluíram-se aqueles abaixo de 40 anos e os diabéticos, sendo que a populaçäo considerada para este estudo foi de 1.741 pacientes. O protocolo do projeto consiste de anamnese direcionada, aferiçäo da pressäo arterial (PA), glicemiaportiras reativas, PIO e fundoscopia direta e indireta. As alteraçöes fundoscópicas pertinentes a retinopatia hipertensiva foram estudadas segundo a classificaçäo de Gans e correlacionadas conforme mencionado anteriormente. Resultados: Dos 1.741 pacientes analisados, 669 (38,43 por cento) säo hipertensos, 645 (37,05 por cento) normotensos e 427 (24,53 por cento) suspeitos de hipertensäo arterial sistêmica (HAS). Foram encontrados 211 (12,12 por cento) pacientes com sinais de RH, sendo 136 (64,46 por cento) do sexo feminino e 75 (35,54 por cento) do sexo masculino; 134 (63,98 por cento) de 40 a 60 anos e 77 (36,02 por cento) com idade superior a 60 anos; predominando as raças branca (75,83 por cento) e negra (11,37 por cento). Do total de pacientes com RH, 154 (73 por cento) eram hipertensos, 17 (2,64 por cento) normotensos e 40 (9,37 por cento) suspeitos de HAS. Dentre os hipertensos com PA controlada, 12,2 por cento apresentavam sinais de retinopatia. Já dentre os hipertensos com PA näo controlada, 25,3 por cento apresentavam sinais da patologia. Conclusäo: A prevalência de RH foi maior nos hipertensos comparativamente aos normotensos e suspeitos de HAS (p<0,001, OR=5,32). Os pacientes negros (p<0,05 e OR= 1,67), os hipertensos com PA näo controlada (p<0,01, OR=2,44) e os acima de 60 anos (p<0,001, ORTl,85) apresentaram maiores chances de desenvolverem RH.