Browsing by Author "Marques-Neves, C"
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- Guidelines for the Management of Center-Involving Diabetic Macular Edema: Treatment Options and Patient MonitorizationPublication . Figueira, J; Henriques, J; Carneiro, A; Marques-Neves, C; Flores, R; Castro-Sousa, JP; Meireles, A; Gomes, N; Nascimento, J; Amaro, M; Silva, RDiabetic macular edema (DME) is the main cause of visual impairment associated with diabetic retinopathy (DR) and macular laser, during approximately three decades, and was the single treatment option. More recently, intravitreous injections of anti-angiogenics and corticosteroids modified the treatment paradigm associated with significant vision improvements. Nevertheless, not all patients respond satisfactorily to anti-VEGF or corticosteroid injections, so an adequate treatment choice and a prompt switch in therapeutic class is recommended. Several algorithms and guidelines have been proposed for treating center involving DME to improve patients' vision and quality of life. However, in Portugal, such guidelines are lacking. The present review aimed to provide guidelines for the treatment options and patient monitorization in the management of center-involving DME. We recommend anti-vascular endothelial growth factor (VEGF) as first-line therapy after a clinical evaluation accompanied by a rigorous metabolic control. Depending on the response obtained after 3-6 monthly intravitreal injections we suggest switching outside the class in case of a non-responder, maintaining the anti-VEGF-therapy in responders to anti-angiogenics. The treatment regimen for Dexamethasone intravitreal implant (DEXii) should be pro-re-nata with bi-monthly or quarterly monitoring visits (with a scheduled visit at 6-8 weeks after DEXii for intraocular pressure control). If a patient does not respond to DEXii, switch again to anti-VEGF therapy, combine therapies, or re-evaluate patients diagnose. There is a resilient need to understand the disease, its treatments, regimens available, and convenience for all involved to propose an adequate algorithm for the treatment of diabetic retinopathy (DR) and DME in an individualized regimen. Further understanding of the contributing factors to the development and progression of DR should bring new drug discoveries for more effective and better-tolerated treatments.
- Impacto do Diâmetro do Nervo Óptico na Amplitude de Pulso Ocular no Glaucoma Primário de Ângulo AbertoPublication . Abegão Pinto, L; Ferreira, J; Patrício, M; Rios, C; Cunha, JP; Marques-Neves, CIntrodução: A pressão intra-craniana (PIC) tem sido descrita como estando envolvida no glaucoma primário de ângulo aberto (GPAA). A sua avaliação está contudo limitada pela necessidade de métodos invasivos, como a punção lombar. A ecografia ocular permite uma avaliação indirecta da PIC através da medição do diâmetro da bainha do nervo óptico (NO). Desconhece-se se esta nova variável tem capacidade de modular factores de risco normalmente investigados em doentes com GPAA. Objectivo: Avaliar o impacto do diâmetro da bainha do NO na pressão intra-ocular (PIO) e na amplitude de pulso ocular (OPA) de doentes com GPAA. Métodos: Quinze doentes com GPAA foram submetidos a medição da PIO por tonometria de contorno dinâmico, avaliação topográfica do disco óptico e ecografia ocular modo B com sonda doppler. Apenas o olho com maior dano glaucomatoso foi seleccionado por doente. Resultados: A média do diâmetro da bainha do NO foi de 5,6±0,67mm, a PIO média de 17,8±2,2mmHg e a OPA de 3,1±1,7mmHg. O diâmetro da bainha do NO correlacionou-se negativamente a OPA (r=-0.54, p=0.05), não tendo influenciado a PIO (r=-0,25, p=0,41). Da avaliação hemodinâmica, apenas o índice de resistência da artéria central da retina (CRA) foi influenciado pelo diâmetro da bainha do NO (r=-0.52, p=0.04). Conclusão: O diâmetro da bainha do NO correlaciona-se negativamente com a OPA. Este efeito poderá ser explicado pela alteração da resistência vascular da artéria que atravessa este espaço subaracnoideu, a CRA. O estudo da região retrobulbar e do balanço entre as pressões aí exercidas é assim um campo cuja importância será crescente na avaliação do doente com GPAA.
- Lack of Spontaneous Venous Pulsation: Possible Risk Indicator in Normal Tension Glaucoma?Publication . Abegão Pinto, L; Vandewalle, E; De Clerck, E; Marques-Neves, C; Stalmans, IPURPOSE: Recently, the absence of spontaneous venous pulsation (SVP) has been suggested as a vascular risk factor for primary open-angle glaucoma (POAG). As the mechanism behind this phenomenon is still unknown, the authors have studied this vascular component using colour Doppler imaging (CDI). METHODS: A total of 236 patients were divided into three diagnostic groups: healthy controls (81), POAG (86) and normal tension glaucoma (NTG; 69). All subjects were submitted to CDI studies of the retrobulbar circulation, intraocular pressure measurements and assessment of SVP existence. Mann-Whitney, chi-square contingency tables and Spearman correlations were used to explore differences and correlations between variables in the diagnostic groups. RESULTS: Eighty-two percent of healthy controls had SVP (66/81), while a smaller numbers were registered in both glaucoma groups: POAG - 50% (43/86); NTG - 51% (35/69). In NTG patients, but not in POAG patients, the prevalence of the SVP phenomenon decreases with increased glaucoma damage (p = 0.04; p = 0.55, respectively). Overall glaucoma patients from both groups had lower central retinal vein (CRV) velocities than the healthy controls (p < 0.05). NTG patients with SVP had less severe visual field defects (mean defect -6.92 versus -11.1, p < 0.05), higher [correction added after online publication 21 September 2012; the word 'higher' has been inserted to replace the word 'lower'] peak systolic and mean flow velocities in the central retinal artery (p < 0.01; p < 0.05, respectively) as well as higher [correction added after online publication 21 September 2012; the word higher has been inserted to replace the word lower] maximal velocities and RI of the CRV (p < 0.02; p < 0.05, respectively). CONCLUSIONS: Glaucoma patients have a decrease in CRV velocities. SVP is less prevalent in glaucoma patients than in healthy individuals. This phenomenon apparently reflects different hemodynamic patterns in the central retinal vessels. This variable may be of particular importance in NTG patients, where it may be associated with more advanced functional damage.
- Ocular Pulse Amplitude and Doppler Waveform Analysis in Glaucoma PatientsPublication . Abegão Pinto, L; Vandewalle, E; Willekens, K; Marques-Neves, C; Stalmans, IPURPOSE: To determine the correlation between ocular blood flow velocities and ocular pulse amplitude (OPA) in glaucoma patients using colour Doppler imaging (CDI) waveform analysis. METHOD: A prospective, observer-masked, case-control study was performed. OPA and blood flow variables from central retinal artery and vein (CRA, CRV), nasal and temporal short posterior ciliary arteries (NPCA, TPCA) and ophthalmic artery (OA) were obtained through dynamic contour tonometry and CDI, respectively. Univariate and multiple regression analyses were performed to explore the correlations between OPA and retrobulbar CDI waveform and systemic cardiovascular parameters (blood pressure, blood pressure amplitude, mean ocular perfusion pressure and peripheral pulse). RESULTS: One hundred and ninety-two patients were included [healthy controls: 55; primary open-angle glaucoma (POAG): 74; normal-tension glaucoma (NTG): 63]. OPA was statistically different between groups (Healthy: 3.17 ± 1.2 mmHg; NTG: 2.58 ± 1.2 mmHg; POAG: 2.60 ± 1.1 mmHg; p < 0.01), but not between the glaucoma groups (p = 0.60). Multiple regression models to explain OPA variance were made for each cohort (healthy: p < 0.001, r = 0.605; NTG: p = 0.003, r = 0.372; POAG: p < 0.001, r = 0.412). OPA was independently associated with retrobulbar CDI parameters in the healthy subjects and POAG patients (healthy CRV resistance index: β = 3.37, CI: 0.16-6.59; healthy NPCA mean systolic/diastolic velocity ratio: β = 1.34, CI: 0.52-2.15; POAG TPCA mean systolic velocity: β = 0.14, CI 0.05-0.23). OPA in the NTG group was associated with diastolic blood pressure and pulse rate (β = -0.04, CI: -0.06 to -0.01; β = -0.04, CI: -0.06 to -0.001, respectively). CONCLUSIONS: Vascular-related models provide a better explanation to OPA variance in healthy individuals than in glaucoma patients. The variables that influence OPA seem to be different in healthy, POAG and NTG patients.
- Ophthalmic Artery Doppler Waveform Changes Associated with Increased Damage in Glaucoma PatientsPublication . Abegão Pinto, L; Vandewalle, E; De Clerck, E; Marques-Neves, C; Stalmans, IPURPOSE: To characterize Doppler waveform variables (early systolic acceleration [ESA] and systolic/diastolic mean velocity ratios [Sm/Dm]) of the Ophthalmic Artery (OA) by color Doppler imaging (CDI) in eyes with primary open-angle glaucoma (POAG). METHODS: Analysis of CDI examinations of the retrobulbar circulation of patients with POAG (n = 102), normal tension glaucoma (NTG, n = 89), and healthy controls (n = 59) by a condition-masked investigator. One-way ANOVA, chi-square, and Spearman's rank correlation tests were used to determine differences, establish comparisons, and to explore associations between variables, respectively. RESULTS: The overall Doppler waveform presented a shift to the right in the glaucoma groups, with significantly lower Sm/Dm ratios when compared to the control group (healthy: 2.94 ± 0.86, POAG: 2.60 ± 0.67, NTG: 2.63 ± 0.84; P = 0.01). ESA was significantly lower in the glaucoma groups (healthy: 688.8 ± 484 cm·s(-2), POAG: 548.1 ± 419 cm·s(-2), NTG: 548.5 ± 337 cm·s(-2); P = 0.03). No statistical differences were, however, detected in the OA velocities or resistance index (P ranged between 0.08 and 0.96). In the glaucoma groups, waveform parameters such as ESA, acceleration time, and systolic mean velocities correlated with systemic blood pressure variables (P < 0.05). In these groups, negative correlations were detected between Sm/Dm ratios and the degree of visual field defects (POAG: P = 0.01; r = -0.25) and retinal nerve fiber layer thickness (NTG: P = 0.02; r = -0.25). CONCLUSIONS: The pattern of blood flow velocities in the OA throughout the cardiac cycle seems to be altered in glaucoma patients. Further studies on how systemic blood pressure affects waveform variables in glaucoma patients may provide a better understanding of an underlying vascular dysfunction.