Aspherical IOLs: clinical evaluation and options

Com a utilização de lentes intraoculares (LIOs) asféricas na cirurgia de catarata, o oftalmologista é capaz de oferecer, além da melhora da acuidade visual pela remoção do cristalino opacificado, benefícios adicionais como, por exemplo, a redução de aberrações ópticas oculares, que diminuem a sensibilidade ao contraste.Foram revisadas publicações recentes sobre LIOs asféricas e adicionadas conclusões de nossos estudos na área, a fim de expor neste artigo nossa percepção a respeito da influência da utilização de LIOs que diminuem a aberração esférica do olho, na qualidade visual após a cirurgia da catarata.With aspherical intraocular lens (IOL), phakectomy could be more than removal of cataract, it also could means an improvement in optical quality of the eye. In this article, recently published studies on aspherical IOLs and exams to access optical quality were reviewed

Comparison of different surgical approaches for pediatric cataracts: complications and rates of additional surgery during long-term follow-up

OBJECTIVES: To compare long-term postoperative complications of pediatric cataract surgery with primary intraocular lens (IOL) implantation associated with posterior capsulotomy (PC) and anterior vitrectomy (AV) between patients treated with a corneal or pars plicata/pars plana approach. METHODS: Children who underwent cataract surgery with in-the-bag primary IOL implantation were divided into two groups according to PC and AV surgical approach: a corneal approach (group 1) and a pars plicata/pars plana approach (group 2). Only patients with a follow-up duration of more than two years were included. Longterm surgical outcomes were retrospectively reported. RESULTS: The mean follow-up period was 10.00±3.13 years. No cases of glaucoma or retinal detachment were reported. The mean age at surgery was 34.57±22.66 months. Forty-six children were included (27 eyes in group 1 and 29 eyes in group 2). The most frequent postoperative complication was corectopia, followed by visual axis opacification. Both complications occurred more frequently in group 1 (po0.001). After cataract surgery, the rate of additional surgeries in group 1 was 51.9%, while in group 2, the rate was 27.6% (p=0.1132). CONCLUSION: The pars plicata/pars plana approach with PC and vitrectomy with primary in-the-bag IOL implantation for pediatric cataracts is a safe procedure

Role of Optical Coherence Tomography on Corneal Surface Laser Ablation

This paper focuses on reviewing the roles of optical coherence tomography (OCT) on corneal surface laser ablation procedures. OCT is an optical imaging modality that uses low-coherence interferometry to provide noninvasive cross-sectional imaging of tissue microstructure in vivo. There are two types of OCTs, each with transverse and axial spatial resolutions of a few micrometers: the time-domain and the fourier-domain OCTs. Both have been increasingly used by refractive surgeons and have specific advantages. Which of the current imaging instruments is a better choice depends on the specific application. in laser in situ keratomileusis (LASIK) and in excimer laser phototherapeutic keratectomy (PTK), OCT can be used to assess corneal characteristics and guide treatment decisions. OCT accurately measures central corneal thickness, evaluates the regularity of LASIK flaps, and quantifies flap and residual stromal bed thickness. When evaluating the ablation depth accuracy by subtracting preoperative from postoperative measurements, OCT pachymetry correlates well with laser ablation settings. in addition, OCT can be used to provide precise information on the morphology and depth of corneal pathologic abnormalities, such as corneal degenerations, dystrophies, and opacities, correlating with histopathologic findings.Cleveland Clin Fdn, Cole Eye Inst, Cleveland, OH 44114 USAAltino Ventura Fdn, Dept Ophthalmol, Recife, PE, BrazilUniv Fed Rio de Janeiro, Dept Ophthalmol, Rio de Janeiro, RJ, BrazilUniversidade Federal de São Paulo, Dept Ophthalmol, São Paulo, SP, BrazilUniversidade Federal de São Paulo, Dept Ophthalmol, São Paulo, SP, BrazilWeb of Scienc

Mini-rhexis for white intumescent cataracts

PURPOSE: To compare the intraoperative safety of two techniques of capsulorhexis for intumescent white cataracts: traditional one-stage continuous curvilinear capsulorhexis and two-stage continuous curvilinear capsulorhexis. METHODS: This prospective comparative randomized study included two groups: the 1-CCC group (11 patients) received traditional one-stage continuous curvilinear capsulorhexis with 5-6 mm diameter, and the 2-CCC (13 patients) group received a deliberately small continuous curvilinear capsulorhexis that was secondarily enlarged, or a two-stage continuous curvilinear capsulorhexis. Patients were stratified according to cataract subset, which was characterized echographically. Six patients were considered as type 1, fifteen as type 2 and three as type 3. Type 1 included intumescent white cataracts with cortex liquefaction and extensive internal acoustic reflections, type 2 included white cataracts with voluminous nuclei, a small amount of whitish solid cortex, and minimal internal acoustic reflections, and type 3 included white cataracts with fibrous anterior capsules and few internal echo spikes. RESULTS: With the one-stage technique, 46.15% of patients had leakage of the liquefied cortex; in addition, the surgeon perceived high intracapsular pressure in 61.53% of cases. Anterior capsule tears occurred in 23.07% of cases, discontinuity of capsulorhexis in 30.79% of cases and no posterior capsular rupture occurred. With the two-stage technique, leakage of the liquefied cortex occurred in 45.45% of cases; additionally, the surgeon perceived high intracapsular pressure in 36.36% of cases. No anterior capsule tears, discontinuity of capsulorhexis or posterior capsular rupture occurred. Considering each cataract subset, there was a higher incidence of leakage for type 2 as compared to types 1 and 3. CONCLUSIONS: Two-stage continuous curvilinear capsulorhexis helps prevent unexpected radial tears of the initial capsulotomy from high intracapsular pressure, sudden radialization of the CCC and other intraoperative complications due to high intracapsular pressure, thus providing a safe cataract surgery in cases of white cataracts. These findings were supported by ultrasonography

Changes on the Amsler grid test in patients with senile cataract

OBJETIVO: Verificar a influência de alguns tipos de opacidade lenticular no teste da tela de Amsler entre portadores de catarata senil. MÉTODOS:Foram avaliados 200 pacientes portadores de catarata senil através da aplicação da tela de Amsler, antes e após a cirurgia. O estudo foi feito em um único centro, simples cego, randomizado e prospectivo. Os pacientes foram submetidos a exame de acuidade visual (AV) corrigida, para longe e perto, biomicroscopia do segmento anterior e da região macular. RESULTADOS:A acuidade visual média pré-operatória para longe dos 200 pacientes foi de 0,5 logMAR (20/60 Tabela de Snellen). Após a cirurgia, dos 11 pacientes que haviam apresentado alteração na tela de Amsler pré-operatória, dez não tiveram alteração no exame de reavaliação da tela. Os 10 indivíduos apresentaram acuidade visual pós-operatória, com a melhor correção óptica, para distância de 20/20 e para perto de J1. No presente estudo foi constatado 5,5% com alteração na tela de Amsler antes da cirurgia, em 5% dos pacientes estas alterações estavam diretamente relacionados a opacidade do cristalino e 0,5% relacionados a opacidade vítrea. CONCLUSÃO: Conclui-se que a alteração no exame da tela de Amsler pode ser diretamente relacionada à catarata, na ausência de alterações maculares clínicas.PURPOSE: To assess the influence of some forms of lenticular opacification in the Amsler grid test among patients suffering from senile cataract. METHODS: Randomized, prospective interventional trial. Two hundred patients with senile cataract were evaluated with Amsler grid, measurement of best corrected visual acuity for near distance and far distance, biomicroscopy of the anterior segment and macular region. RESULTS: With a two months minimum of follow-up, the average visual acuity after surgery for far distance among the 200 patients was 0.48 logMAR, 11 (5.5%) had changes in the Amsler grid test before surgery. After surgery, from the 11 subjects with changes in the preoperative Amsler grid test, 10 had no more changes in the Amsler grid. These 10 subjects had postoperative best corrected visual acuity of 20/20, and Jaeger 1, no abnormalities of the fundus having been detected. Under this study conditions, the prevalence of changes in the Amsler grid test was 5.5%, and in 5% of the patients these changes were likely related to cataract whereas in 0.5% they were related to vitreous opacification. CONCLUSION: Some patient with cataract showed changes in the Amsler grid test that can be directly related to cataract, in the absence of clinically detected macular disorders

The effect of subconjunctival bevacizumab on corneal neovascularization, inflammation and re-epithelization in a rabbit model

PURPOSE: To evaluate the use of subconjunctival bevacizumab on corneal neovascularization in an experimental rabbit model for its effect on vessel extension, inflammation, and corneal epithelialization. METHODS: In this prospective, randomized, blinded, experimental study, 20 rabbits were submitted to a chemical trauma with sodium hydroxide and subsequently divided into two groups. The experimental group received a subconjunctival injection of bevacizumab (0.15 m; 3.75 mg), and the control group received an injection of 0.15 ml saline solution. After 14 days, two blinded digital photograph analyses were conducted to evaluate the inflammation/diameter of the vessels according to pre-established criteria. A histopathological analysis of the cornea evaluated the state of the epithelium and the number of polymorphonuclear cells. RESULTS: A concordance analysis using Kappa's statistic showed a satisfactory level of agreement between the two blinded digital photography analyses. The neovascular vessel length was greater in the control group (p<0.01) than in the study group. However, the histopathological examination revealed no statistically significant differences between the groups in terms of the state of the epithelium and the number of polymorphonuclear cells. CONCLUSIONS: Subconjunctival bevacizumab inhibited neovascularization in the rabbit cornea. However, this drug was not effective at reducing inflammation. The drug did not induce persistent corneal epithelial defects

Posterior Capsule Opacification after Cataract Surgery in Children Over Five Years of Age with Square-edge Hydrophobic versus Hydrophilic Acrylic Intraocular Lenses: A Prospective Randomized Study

OBJECTIVE: To compare the effects of hydrophobic and hydrophilic materials in square-edged acrylic intraocular lenses (IOLs) on the development of posterior capsule opacification (PCO) after pediatric cataract surgery. METHODS: Patients were randomly assigned to group 1 (hydrophobic acrylic square-edged IOLs; 13 eyes) or group 2 (hydrophilic acrylic square-edged IOLs; 13 eyes). The study evaluated PCO rates using Evaluation of Posterior Capsule Opacification (EPCO) 2000 software at one, three, six and 12 months postoperatively. Postoperative measurements also included corrected distance visual acuity (CDVA), neodymium:yttrium-aluminum-garnet (Nd:YAG) capsulotomy and postoperative complications other than PCO. RESULTS: Both groups had significant increases in PCO rates after one year. Comparison of the groups showed no significant differences in the EPCO scores at three (group 1, 0.007±0.016 vs group 2, 0.008±0.014; p=0.830), six (group 1, 0.062±0.103 vs group 2, 0.021±0.023; p=0.184), or twelve months postoperatively (group 1, 0.200±0.193 vs group 2, 0.192±0.138; p=0.902). We also found no significant group differences regarding the change (delta, D) in EPCO scores between three and six months (group 1, 0.055±0.09 vs group 2, 0.013±0.02; p=0.113) or between six and twelve months postoperatively (group 1, 0.139±0.14 vs group 2, 0.171±0.14; p=0.567). Twenty-three percent of patients required Nd:YAG capsulotomy at the twelve-month visit. CONCLUSIONS: No differences in PCO rates were found between hydrophobic and hydrophilic acrylic squareedged IOLs in children between five and twelve years of age at one year of follow-up

Phacoemulsification versus extracapsular extraction on public health care system: cost analysis to the hospital, to the government and to the society

OBJETIVO: Comparar custos da cirurgia de catarata em larga escala para um hospital público, para o governo e para a sociedade, pelas técnicas de facoemulsificação (FACO) e extração extracapsular (EECP). MÉTODOS: Foi realizada revisão baseada principalmente em diversos estudos clínicos realizados entre 2002 e 2010, no Centro Cirúrgico Ambulatorial do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. RESULTADOS: Os gastos estimados com os insumos utilizados para as cirurgias foram de R$468,92 no grupo FACO e R$ 259,96 no grupo EECP. As despesas hospitalares com o acompanhamento pós-operatório foram em média de R$16,40 (42$ 44,58 por paciente a mais que o grupo FACO. CONCLUSÃO: O incentivo e o investimento governamental para a realização da FACO no SUS são socialmente justificados, deve-se considerar também a economia dos pacientes e do sistema empresarial, bem como as vantagens clínicas para os pacientes e vantagens econômicas para os hospitais

Influence of aspheric intraocular lens on frequency doubling technology and contrast sensitivity: a fellow eye study

Purpose: To evaluate whether implantation of an aspheric intraocular lens (IOL) results in reduced ocular aberrations and improved contrast sensitivity after cataract surgery and, therefore, changes on frequency-doubling technology (FDT) testing. Methods: The present prospective clinical study enrolled 25 patients with bilateral cataract (50 eyes), who randomly received either an aspheric (Akreos AO) or a spherical (Akreos Fit) IOL in one eye and the other IOL in the second eye. Assessment 12 months postoperatively included photopic and mesopic contrast sensitivity testing. Higher-order aberrations (HOAs) were computed. FDT testing was divided into four areas to evaluate the variation of the values at different points. The median values of the local pattern thresholds (median area contrast sensitivity [MACS]) obtained with that division were calculated. Results: The Akreos AO group obtained statistically significantly lower values of HOAs and spherical aberration compared with the Akreos Fit group. There was a statistically significant between-group difference in contrast sensitivity under mesopic conditions at all spatial frequencies. No statistically significant differences were observed in mean deviation and pattern standard deviation. The aspheric IOL exhibited higher MACS in all areas, although a statistically significant difference was reached only in the 20-degree field area (P=0.043). Conclusion: Aspheric IOLs significantly reduced spherical aberration and HOAs, improving mesopic contrast sensitivity. Although there was a trend toward slightly improved FDT in the aspheric IOL group, it was not statistically significant