State of the art in chromovitrectomy / Estado da arte da cromovitrectomia

Vitrectomy is a surgery that involves complex and delicate techniques that treat diseases such as macular hole, epiretinal membrane and diabetic macular edema. Chromovitrectomy is one of these techniques and includes the use of coloring agents such as vital dyes or crystals to enhanced visibility of transparent structures during vitrectomy. The aim of this study was to present a modern approach, based on scientific evidence, about the application and indication of vital coloring agents during vitrectomy. The use of such agents has made this surgery more predictable and has increased its post-operative prognosis. Although research on chromovitrectomy is currently expanding there is still not an established gold standard dyeing agent.

A cirurgia vitreorretiniana é uma cirurgia que envolve técnicas complexas e delicadas que tratam doenças como buraco macular, membrana epirretiniana e o edema macular diabético. A cromovitrectomia é uma dessas técnicas que incluem o uso de corantes compostos de pigmentos vitais ou cristais para melhorar a visibilização de estruturas transparentes durante a cirurgia de vitrectomia. O objetivo desse artigo foi apresentar uma abordagem atual, baseada em evidências, sobre a aplicação e indicação de corantes vitais durante a cirurgia vitreorretiniana. O emprego desses corantes possibilitou uma maior previsibilidade para a cirurgia, melhorando assim seu prognóstico pós-operatório. Apesar do campo da cromovitrectomia está em plena expansão de pesquisas, um corante gold standard para cromovitrectomia ainda não está estabelecido.

Hemorragia submembrana limitante interna em paciente após Valsalva: relato de caso / Sub-internal limiting membrane hemorrhage in Valsalva retinopathy: case report

Relatar o caso de uma paciente com retinopatia por Valsalva que evoluiu com hemorragia submembrana limitante interna e foi submetida à vitrectomia via pars plana, tendo tido melhora da acuidade visual. Paciente hígida de 35 anos evoluiu com redução súbita e indolor da acuidade visual do olho direito, após crise de tosse. Ao exame oftalmológico, apresentava hemorragia pré-macular, sem outras alterações. Inicialmente, optou-se pela conduta expectante, porém não houve regressão completa da hemorragia. Então, foi indicada a vitrectomia via pars plana associada à remoção da membrana limitante interna, havendo melhora considerável da acuidade visual, sem complicações peri-operatórias e sem alterações significativas à tomografia de coerência óptica, autofluorescência ou eletrorretinograma multifocal. Neste caso, o tratamento da hemorragia sub-membrana limitante interna com a cirurgia vitreorretiniana resultou em melhora da acuidade visual e regressão da hemorragia.

To report a case of a patient with Valsalva retinopathy that developed sub-internal limiting membrane hemorrhage, underwent pars plana vitrectomy and had visual acuity improvement after that. A 35-year-old healthy patient presented with sudden and painless vision loss of her right eye, after coughing. During the ophthalmologic evaluation, she had a pre-macular hemorrhage and no other abnormalities. Initially, we chose for expectant management, but the hemorrhage did not clear totally. Thus, pars plana vitrectomy associated with internal limiting membrane peeling was indicated, with considerable improvement of her visual acuity, without perioperative complications or significant findings in the optical coherence tomography, autofluorescence and multifocal electroretinogram. In this case, sub-internal limiting membrane hemorrhage treatment with vitreoretinal surgery was relatively useful, with visual acuity improvement and resolution of sub-internal limiting membrane hemorrhage.

A preliminary study of Heavy Brilliant Blue G for internal limiting membrane staining in macular hole surgery.

Context: Surgical outcomes of vitrectomy for idiopathic macular hole using a “heavy” Brilliant Blue G (HBBG) solution for staining and removal of the internal limiting membrane (ILM). Settings and Design: Prospective interventional case series conducted in a tertiary eye care hospital. Materials and Methods: Nineteen patients (20 eyes) with idiopathic macular hole were enrolled to undergo vitrectomy with ILM peeling using HBBG. BBG dye was made heavy by mixing with 10% dextrose normal saline (DNS) solution in 2:1 ratio. The adequacy of ILM staining was noted intraoperatively. The closure rates of macular hole and visual improvement were recorded. Patients were followed up postoperatively on day 1, week 1, and subsequently at 1, 3, and 6 months, and every 6th month thereafter. Statistical Analysis: Wilcoxon signed-rank test was used; P < 0.05 was considered significant. Results: Preoperative best-corrected visual acuity (BCVA) ranged from 20/1000 to 20/63 (median: 20/100). Intraoperatively, the ILM stained very well in all eyes, and was easily removed. All macular holes closed postoperatively. The mean follow-up was 6.15 ± 2 months (range: 4-10; median: 6 months). Final BCVA ranged from 20/20 to 20/80 (median: 20/40), amounting to a significant visual improvement (P = 0.0001). BCVA improved by 1-8 Snellen lines in 19 eyes (95%); 16 eyes (80%) improved by ≥2 lines; 13 eyes (65%) achieved a final BCVA of 20/40 or better. Conclusions: Addition of 10% DNS to BBG dye allowed good ILM staining with less dye during macular hole surgery, and provided excellent anatomic and visual outcomes.

Resultado funcional e índice macular em portadores de buraco macular submetidos à cirurgia com remoção da membrana limitante interna / Functional outcome and macular index in macular hole patients who underwent surgery with internal limiting membrane removal

OBJETIVOS: Avaliar o resultado funcional e o índice macular dos portadores de buraco macular submetidos à cirurgia com remoção da membrana limitante interna. MÉTODOS: Quinze olhos de 15 pacientes com buraco macular estágios 2, 3 e 4 foram incluídos no estudo. Todos foram submetidos à cirurgia de buraco macular convencional com remoção da membrana limitante interna corada pelo azul de tripan. Melhor acuidade visual com correção e cortes transversais medidos por tomografia de coerência óptica (OCT) foram avaliados no pré- e pós-operatório. O índice macular (razão entre a altura e base do buraco macular) foi calculado e correlacionado com o diâmetro mínimo do buraco macular e o ganho de acuidade visual pós-operatória. RESULTADOS: Obteve-se fechamento do buraco macular em todos pacientes operados. Em 86,7 por cento, houve ganho de pelo menos três linhas de visão. O índice macular demonstrou correlação negativa significante com o diâmetro mínimo (r=0,811). Não foi observada correlação significante entre o índice macular e o ganho de acuidade visual pós-operatória (r=0,351). CONCLUSÃO: Os resultados funcionais na cirurgia do buraco macular com remoção da membrana limitante interna foram bons neste grupo de pacientes. O índice macular demonstrou ser compatível com a configuração espacial do buraco macular, porém não foi preditor de resultados visuais.

PURPOSE: To evaluate the functional outcome and macular index in patients with macular hole who underwent surgery with internal limiting membrane removal. METHODS: Fifteen eyes of 15 patients with idiopathic macular hole stages 2, 3 or 4 were enrolled in this study. All patients underwent conventional macular hole surgery with trypan blue staining to remove the internal limiting membrane. The best-corrected visual acuity and cross-sectional images of macular hole measured by optical coherence tomography (OCT) were evaluated pre- and postoperatively. The macular hole index (ratio of hole height to base diameter of the hole) was calculated and correlated with minimum diameter of the macular hole and postoperative gain in visual acuity. RESULTS: Macular hole closure was observed in all operated patients. In 86.7 percent, there was a visual gain of at least three lines. Macular hole index was significantly negative correlated with the minimum diameter of the macular hole (r=0.811). There was no significant correlation between macular index and postoperative gain in visual acuity (r=0.351). CONCLUSION: Functional outcomes with internal limiting membrane removal were good in this group of patients. Macular index was compatible with spatial configuration of the macular hole, however visual outcomes were not predictable.

Reorganization of Photoreceptor Layer on Optical Coherence Tomography Concurrent with Visual Improvement after Macular Hole Surgery

To report three cases in which reorganization of the photoreceptor layer on optical coherence tomography (OCT) was concurrent with long-term visual recovery after macular hole surgery. Serial OCT scans of three eyes in which visual acuity continued to improve for 1 or more years after successful macular hole surgery were reviewed. Case 1. At postoperative four weeks, visual acuity was 20/100 with disorganized photoreceptor layer on OCT. The photoreceptor layer had been reorganized and visual acuity had improved to 20/25 by 1 year. Case 2. Two weeks after the operation, visual acuity was 20/125 and disorganization of the photoreceptor layer was noted. Visual acuity improved to 20/50 by four months. The photoreceptor layer had been partly reorganized and had appearance of a broken line. Visual acuity had improved to 20/40 and the photoreceptor layer had been reorganized further with a residual defect on OCT by 15 months. Case 3. Visual acuity at two weeks was 20/100. OCT revealed disorganization of the photoreceptor layer. Six months after the operation, the partly reorganized photoreceptor layer appeared as a broken line and visual acuity had reached 20/80. Visual acuity had improved further to 20/40 by 1 year, concurrent with improved organization of the photoreceptor layer. The reorganization of the photoreceptor layer plays a part in long-term improvement of visual acuity after macular hole surgery.

Visual outcome and electron microscopic features of indocyanine green-assisted internal limiting membrane peeling from macular hole of various aetiologies.

PURPOSE: To describe the visual outcome of internal limiting membrane (ILM) peeling for macular hole of various aetiologies and ultrastructural features of the ILM. MATERIALS AND METHODS: The study was conducted on 40 eyes of 38 patients. Thirty eyes with full thickness macular hole were treated with vitrectomy and removal of ILM. Ten eyes with retinal detachment served as negative controls and these patients underwent vitrectomy and ILM removal. The surgical specimens were examined by transmission electron microscopy. RESULTS: The anatomical success rate of the first operation was 90% in idiopathic and myopic groups, whereas it was 100% in traumatic macular hole group. Visual improvement of (3) two lines was noted in 80% of the cases. Electron microscopy revealed the presence of ILM in all surgical specimens. Proliferation of astrocytes and synthesis of new collagen along the inner surface of ILM was noted in the surgical specimens. CONCLUSION: Our findings suggest that the ILM removal helps in closure of the macular hole and retinal reattachment. Vitrectomy with ILM peeling is a reasonable surgical approach to treat macular holes of idiopathic, myopic and traumatic aetiology.

Effect of Internal Limiting Membrane Removal in Treatment of Retinal Detachment Caused by Myopic Macular Hole

The purpose of this study was to evaluate the anatomical outcomes of vitrectomy with internal limiting membrane removal in highly myopic eyes with retinal detachment caused by a macular hole. Nineteen, consecutive, highly myopic eyes with full thickness macular hole with retinal detachment were treated by vitrectomy with internal limiting membrane removal, endolaser photocoagulation on the center of the hole and fluid gas exchange. In five eyes with other peripheral breaks, scleral buckling (3 cases), encircling (1 case) and barrier laser (1 case) were combined. In 15 eyes (79.0%) the macular hole was closed after the initial surgery. In 4 eyes (21%) the macular hole was reopened, but these were successfully treated with fluid gas exchange (1 case) or macular buckling (3 cases). The visual acuity was improved in 15 eyes (79.0%). In conclusion, these results suggest that the removal of the perifoveal internal limiting membrane may be an important adjuvant in the treatment of the myopic macular hole with retinal detachment.

Ultrastructure of surgically excised subfoveal neovascular membranes

We studied the ultrastructural features of four consecutive subfoveal neovascularmembranes (SFNM) associated with age-related macular degeneration. Cellular components of the membranes included retinal pigment epithelial (RPE) cells, endothelium-lined vascular channels, macrophages, myofibroblasts, fibrocytes, glial cells, erythrocytes, and lymphocytes. Extracellular interstitial constituents included collagen fibrils, basal laminar deposits, fibrin and young elastic fibrils. These findings show that SFNMs consist of various cells originating from surrounding tissues and vessels. Among these RPE cells and macrophages are the main cellular components and in conjunction with various extracellular matrix, especially collagen, may play an important role in the formation and maintenance of the membranes.