MARCELO VIEIRA NETTO
Índice h a partir de 2011
10
Projetos de Pesquisa
Unidades Organizacionais
Instituto Central, Hospital das Clínicas, Faculdade de Medicina - Médico
LIM/33 - Laboratório de Oftalmologia, Hospital das Clínicas, Faculdade de Medicina
LIM/33 - Laboratório de Oftalmologia, Hospital das Clínicas, Faculdade de Medicina
15 resultados
Resultados de Busca
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- Intraocular straylight before and after low myopic photorefractive keratectomy with and without mitomycin C(2016) TORRICELLI, Andre Augusto Miranda; PAREDE, Tais Renata Ribeiro; NETTO, Marcelo Vieira; CRESTANA, Francisco Penteado; BECHARA, Samir JacobPurpose: To evaluate ocular straylight before and after photorefractive keratectomy (PRK) for low myopia with and without topical mitomycin (MMC) treatment. Methods: Patients who underwent PRK for low myopia were enrolled into the study. PRK without MMC was performed in 21 eyes (12 patients), whereas PRK with topical 0.02% MMC was performed in 25 eyes (14 patients). Both groups were treated using the NIDEK EC5000 excimer laser. Measurements were performed using the C-Quant straylight meter preoperatively and at two and four months postoperatively. Results: The mean patient age was 30 +/- 4 years, and the mean spherical equivalent refractive error was -2.2 +/- 0.75 D. The mean preoperative intraocular straylight values were 1.07 +/- 0.10 in the PRK without MMC group and 1.07 +/- 0.11 log(s) in the PRK with topical MMC group. At two months after surgery, there was a decrease in mean intraocular straylight values in both groups. However, a significant difference was only reached in the PRK with MMC group [0.98 +/- 0.09 log(s), p=0.002] compared with preoperative values, which was likely due to a greater scatter of measurements in the PRK without MMC group [1.03 +/- 0.13 log(s), p=0.082]. At four months postoperatively, ocular straylight values were not significantly different compared with those at baseline in either the PRK without MMC group [1.02 +/- 0.14 log(s), p=0.26] or in the PRK with topical MMC group [1.02 +/- 0.11 log(s), p=0.13]. Conclusion: PRK for low myopia decreases ocular straylight, and MMC application further reduces straylight in the early postoperative period. However, ocular straylight values do not significantly differ at four months after surgery compared with those at baseline.
- Femtosecond Laser-Assisted LASIK Flap Complications(2016) SANTOS, Allisson Mario dos; TORRICELLI, Andre A. M.; MARINO, Gustavo K.; GARCIA, Renato; NETTO, Marcelo V.; BECHARA, Samir J.; WILSON, Steven E.PURPOSE: To discuss intraoperative and postoperative femtosecond laser-assisted LASIK flap complications and their management. METHODS: Review of published literature. RESULTS: Flap creation is a critical step in LASIK. The femtosecond laser has improved the overall predictability and safety of the lamellar incision, but complications can still occur during or after flap creation. Although many complications (eg, epithelial ingrowth and flap striae) were reduced with the femtosecond laser application, other specific complications have emerged, such as vertical gas breakthrough, opaque bubble layer, and transient light-sensitivity syndrome. CONCLUSIONS: The application of femtosecond laser technology to LASIK flap creation has increased greatly since its introduction. These lasers have improved the safety and predictability of the lamellar incision step. The majority of the femtosecond laser-assisted flap complications can be well managed without significant effects on refractive outcomes.
- Censo Brasileiro de Cirurgia Refrativa(2013) VIEIRA NETTO, Marcelo; ESPÍNDOLA, Rodrigo França de; NOGUEIRA, Rafael Garcia Fernandes; CAMPOS, Mauro; AMBRÓSIO JR., Renato; ANDRADE, Newton Leitão dePURPOSE: To determine preferences and practices of refractive surgeons in Brazil. METHODS: A cross-sectional study was conducted based on the data collected from a questionnaire applied during the VI Brazilian Congress of Cataract and Refractive Surgery and by e-mail sent to all members of that society. Refractive surgery techniques, use of emerging technologies, surgical volume, type of excimer laser and microkeratomes, mitomycin C, postoperative medications were analyzed among others questions. RESULTS: Two hundred ninety-two surgeons replied to the questions. The majority has a surgical volume between 2 and 4 eyes per week (57.60%). Most of the surgeons (64.50%) perform corneal tomography routinely and 22.00% of them do never customize their surgeries. The laser in situ keratomileusis (LASIK) is the main technique performed and when the photorefractive keratectomy (PRK) is applied; most of the surgeons uses mitomycin C (52.60%) in these patients. The excimer laser of choice was the Nidek (26.12%). CONCLUSION: LASIK is the preferred surgical procedure and the majority customizes their refractive surgeries. When photorefractive keratectomy is performed, mitomycin C is used by most of the surgeons (52.60%). Bilateral surgery is routinely performed and the femtosecond laser is still used by few refractive surgeons.
- Quality of vision in refractive and cataract surgery, indirect measurers: review article(2013) PAREDE, Tais Renata Ribeira; TORRICELLI, Andre Augusto Miranda; MUKAI, Adriana; NETTO, Marcelo Vieira; BECHARA, Samir JacobVisual acuity is the measurement of an individual's ability to recognize details of an object in a space. Visual function measurements in clinical ophthalmology are limited by factors such as maximum contrast and so it might not adequately reflect the real vision conditions at that moment as well as the subjective aspects of the world perception by the patient. The objective of a successful vision-restoring surgery lies not only in gaining visual acuity lines, but also in vision quality. Therefore, refractive and cataract surgeries have the responsibility of achieving quality results. It is difficult to define quality of vision by a single parameter, and the main functional-vision tests are: contrast sensitivity, disability glare, intraocular stray light and aberrometry. In the current review the different components of the visual function are explained and the several available methods to assess the vision quality are described.
- Corneal Collagen Cross-linking in Advanced Keratoconus: A 4-Year Follow-up Study(2016) GIACOMIN, Natalia T.; NETTO, Marcelo V.; TORRICELLI, Andre A. M.; MARINO, Gustavo K.; BECHARA, Samir J.; ESPINDOLA, Rodrigo F.; SANTHIAGO, Marcony R.PURPOSE: To analyze the safety and efficacy of standard corneal collagen cross-linking (CXL) in advanced cases of progressive keratoconus after 4 years of follow-up. METHODS: A retrospective case series of patients with advanced progressive keratoconus (stages 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, flat, steep, and apical), pachymetry, and endothelial cell count at the baseline and at 12, 24, and 48 months postoperatively. RESULTS: Forty eyes of 40 patients were enrolled in the study. The mean patient age was 22.5 years (range: 15 to 37 years). Both mean UDVA and CDVA remained stable during the time points; no statistically significant change was noted. Although a slight reduction was observed in all keratometric readings, a statistically significant reduction was only reached in the apical keratometry (P = .037) at 4 years after CXL. A significant reduction in the corneal thickness was also found (ultrasonic: 388 +/- 49 to 379 +/- 48 mu m; slit-scanning: 362 +/- 48 to 353 +/- 51 mu m); however, this change was likely not clinically meaningful. Endothelial cell count was not significantly different at the end of the study. Treatment failure or progression was noted in two patients (5%) over the follow-up period. CONCLUSIONS: Standard CXL treatment was safe and able to stabilize both visual acuity and topographic parameters at 4 years of follow-up in eyes with advanced keratoconus.
- Topographic, Corneal Wavefront, and Refractive Outcomes 2 Years After Collagen Crosslinking for Progressive Keratoconus(2014) GHANEM, Ramon C.; SANTHIAGO, Marcony R.; BERTI, Thais; NETTO, Marcelo V.; GHANEM, Vinicius C.Purpose:The aim was to report the corneal higher-order aberrations (HOA), the topographic metrics, and the visual and refractive outcomes 2 years after performing collagen crosslinking (CXL) for progressive keratoconus. The correlation among corneal HOAs, topographic metrics, and visual acuity changes was also investigated.Methods:This is a prospective case series involving 42 eyes from 32 patients with progressive keratoconus treated with CXL. The main outcomes measured at baseline and 6, 12, and 24 months after treatment were uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), refractive changes, topographic data, and corneal aberrations.Results:Two years after CXL treatment, the UDVA (P < 0.001), CDVA (P < 0.001), and spherical equivalent (P = 0.048) improved significantly. The corneal topographic data revealed significant decreases in apical keratometry (P < 0.001), differential keratometry (P = 0.031), and central keratometry (P = 0.003) compared with the baseline measurements. Aberration analyses revealed a significant reduction in coma (P = 0.016), trefoil (P = 0.018), secondary astigmatism (P < 0.001), quatrefoil (P = 0.031), secondary coma (P < 0.001), and secondary trefoil (P = 0.001). Corneal HOA (except quatrefoil) demonstrated a significant correlation with postoperative CDVA; the highest correlations were for coma (rho = 0.703, P < 0.001), secondary astigmatism (rho = 0.519, P = 0.001), and total HOA (rho = 0.487, P = 0.001). However, the corneal HOA changes were not statistically associated with improved visual acuity. After treatment, the reduction in apical keratometry was the only variable that correlated with the improvement in the CDVA (rho = 0.319, P = 0.042).Conclusions:After 2 years, CXL was found to be effective in improving the UDVA, CDVA, topographic metrics, and most corneal HOAs in eyes with progressive keratoconus. A significant reduction was observed in apical keratometry, and this reduction directly correlated with an improvement in visual acuity.
- Mitomycin C: Biological Effects and Use in Refractive Surgery(2012) SANTHIAGO, Marcony R.; NETTO, Marcelo V.; WILSON, Steven E.Purpose: To provide an overview of the safety and efficacy of mitomycin C (MMC) as adjuvant therapy after refractive surgery procedures. Methods: Literature review. Results: Over the past 10 years, MMC has been used by refractive surgeons to prophylactically decrease haze after surface ablation procedures and therapeutically in the treatment of preexisting haze. Development of MMC treatments has had a significant role in the revival of surface ablation techniques. We reviewed the literature regarding mechanism of action of MMC, its role in modulating wound healing after refractive surgery, and its safety and efficacy as adjuvant therapy applied after primary photorefractive keratectomy surgery or after photorefractive keratectomy re-treatment after laser in situ keratomileusis and other corneal surgeries and disorders. The drug is a potent mitotic inhibitor that effectively blocks keratocyte activation, proliferation, and myofibroblast differentiation. Many studies have suggested that MMC is safe and effective in doses used by anterior surface surgeons, although there continue to be concerns regarding long-term safety. After initial depletion of anterior keratocytes, keratocyte density seems to return to normal 6 to 12 months after the use of MMC when corneas are examined with the confocal microscope. Most clinical studies found no difference between preoperative and postoperative corneal endothelial cell densities when MMC 0.02% was applied during refractive surgery, with exposure time of 2 minutes or less. Conclusions: After more than 10 years of use, MMC has been found to be effective when used for prevention and treatment of corneal haze. Questions remain regarding optimal treatment parameters and long-term safety.
- Visual Performance of an Apodized Diffractive Multifocal Intraocular Lens With+3.00-D Addition: 1-year Follow-up(2011) SANTHIAGO, Marcony R.; WILSON, Steven E.; NETTO, Marcelo V.; ESPINDOLA, Rodrigo F.; SHAH, Ravindra A.; GHANEM, Ramon C.; BECHARA, Samir J.; KARA-JUNIOR, NewtonPURPOSE: To determine whether implantation of a multifocal intraocular lens (IOL) with a lower addition (+3.00 diopters [D]) at the lens plane results in better intermediate visual acuity 1 year after surgery compared with a multifocal IOL with higher addition (+4.00 D). METHODS: This prospective, randomized, double-masked study included 80 eyes from 40 patients. Twenty patients were implanted bilaterally with the ReSTOR +3.00-D add IOL and 20 patients were implanted bilaterally with the ReSTOR +4.00-D add IOL. Primary outcome measures were distance, intermediate, and near visual acuity. Secondary outcomes were defocus curves, best reading distance, mesopic and photopic contrast sensitivity, quality of life, and spectacle independence. Monocular and binocular visual acuity were measured as uncorrected and corrected distance visual acuity at 4 m, uncorrected near and distance-corrected near visual acuity at 40 cm, and uncorrected intermediate visual acuity and distance-corrected intermediate visual acuity at 50, 60, and 70 cm. RESULTS: Twelve months postoperatively, no statistically significant difference between groups in distance and near visual acuity was noted. The ReSTOR +3.00-D add group performed better than the ReSTOR +4.00-D add group at all intermediate distances studied. The ReSTOR +4.00-D group chose a reading distance 8 cm closer than the +3.00-D group. Both groups performed similarly with respect to contrast sensitivity, quality of life, and spectacle independence rates. CONCLUSIONS: Patients implanted with a multifocal IOL with lower addition (ReSTOR +3.00 D) had better performance at intermediate distances compared with the ReSTOR +4.00-D add IOL with similar performance for distance and near visual acuity, contrast sensitivity, and quality of life. [J Refract Surg. 2011;27(12):899-906.] doi:10.3928/1081597X-20110816-01
- Desempenho visual dos pacientes pseudofácicos com diferentes lentes intraoculares(2013) HIDA, Wilson Takashi; NAKANO, Celso Takashi; YAMANE, Iris Souza; MOTTA, Antonio Francisco Pimenta; TZELIKS, Patrick Frenzel; ALENCAR, Luciana Malta de; OSHIKA, Tetsuro; NETTO, Marcelo Vieira; VENTURA, Dora Fix; KARA-JUNIOR, NewtonOBJETIVO: Comparar a performance visual dos pacientes submetidos ao implante das lentes intraoculares multifocais difrativas Tecnis® MF ZM900, Acrysof® Restor® SN60D3, Acrysof® SN60WF e Acrysof® SN60AT. MÉTODOS: Estudo prospectivo comparativo, não randomizado, que incluiu 142 olhos de 71 pacientes com catarata, provenientes do ambulatório de oftalmologia do HC-FMUSP. A avaliação oftalmológica contou com medida da acuidade visual para longa, intermediária e curta distância, sem correção e com a melhor correção óptica, teste de sensibilidade ao contraste, pupilometria e análise de frente de onda por meio do aberrômetro. Todos os exames foram realizados com seis meses de pós-operatório. RESULTADOS: A média de idade dos pacientes foi de 60,7±6,6 anos no grupo Tecnis, 63,1±4,4 anos no grupo Restor e 63,7±4,2 anos no grupo monofocal (SN60AT no olho contralateral SN60WF). A acuidade visual para perto não corrigida e corrigida para longe foi estatisticamente superior nos grupos multifocal Restor e multifocal Tecnis em comparação ao grupo monofocal SN60AT/SN60WF (p<0,001). Não houve diferença estatística entre os grupos na comparação da acuidade visual para longe (p=0,56). A sensibilidade ao contraste fotópica monocular foi estatisticamente inferior nos grupos Restor e Tecnis (p<0,001). A SN60AT apresentou maior aberração esférica comparada a todas as outras lentes (p<0,001). A Tecnis se mostrou com menores valores médios de aberrações esféricas na comparação com a Restor (p<0.001). CONCLUSÃO: A Restor e Tecnis apresentaram melhor acuidade visual para perto do que o grupo monofocal SN60AT/SN60WF. Todas as lentes intraoculares promoveram boa visão para longe. O grupo da Tecnis apresentou melhor sensibilidade de contraste, menos aberrações ópticas e melhor visão intermediária que o grupo Restor.
- Peripheral Sterile Corneal Ring Infiltrate After Riboflavin-UVA Collagen Cross-Linking in Keratoconus(2012) GHANEM, Ramon C.; NETTO, Marcelo V.; GHANEM, Vinicius C.; SANTHIAGO, Marcony R.; WILSON, Steven E.Purpose: To present 7 cases of peripheral sterile corneal infiltrates that occurred after corneal cross-linking (CXL) for progressive keratectasia. Methods: Seven patients who had their progressive keratoconus documented underwent corneal deepithelization and subsequently CXL, which was performed with the application of 0.1% riboflavin with 20% dextran, and exposure to UVA light (370 nm, 2.9-3.1 mW/cm(2)) for 30 minutes. Results: Nearly a week after the procedure, the patients presented with peripheral stromal infiltrates. The ring-like infiltrates were superficial and were present at the 9.0-mm zone. Sterile infiltration was diagnosed. Patients were treated with topical corticosteroids, and complete resolution was achieved after a few weeks of treatment. Conclusions: We hypothesize that the phototoxic effect on the corneal stroma may be the main mechanism that triggers these infiltrates. Alternatively, alterations in antigenicity that occur in native proteins after CXL could result in patients recognizing the proteins as nonself and mounting immune responses.