Estudo da correlação entre estrutura e função no glaucoma por meio da ultrassonografia de alta-resolução e ressonância magnética com a tomografia de coerência óptica e as perimetrias computadorizadas padrão e de frequência duplicada

• Autor(a) principal: Furlanetto, Rafael Lacerda [UNIFESP]
• Data de Publicação: 2015
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da UNIFESP
• Texto Completo: https://sucupira.capes.gov.br/sucupira/public/consultas/coleta/trabalhoConclusao/viewTrabalhoConclusao.jsf?popup=true&id_trabalho=2754573; http://repositorio.unifesp.br/handle/11600/47616
• topic: Primary open-angle glaucoma; Magnetic resonance imaging; Ultrasound; Optic nerve; Geniculate body; Glaucoma primário de ângulo aberto; Ressonância magnética; Ultrassonografia; Nervo óptico corpo geniculado

Purpose: To evaluate the correlation between 20 MHz high-resolution ultrasonography (US) and currently available structural tests for glaucoma in assessing the cup-to-disc ratio (CDR) of the optic nerve head. Further, we aimed to analyze the correlation between structural characteristics of intraorbital optic nerve (ION) and lateral geniculate nucleus (LGN) measured by 3-Tesla magnetic resonance imaging (MRI), and the extent of glaucoma damage, assessed by functional or ocular structural tests. Methods: This was a cross-sectional study. All participants underwent US, MRI, ocular structural testing [optic disc stereophotograph, spectral-domain optical coherence tomography (OCT) and confocal scanning laser ophthalmoscopy] and functional evaluation (standard automated perimetry and frequency doubling technology). Generalized estimating equations, bootstrap resampling method for clustered data, area under receiving operator characteristics curve (AUC) and Bland-Altman plots were used in statistical analysis. Results: We included 41 glaucoma patients and 12 age- and sexmatched healthy volunteers; 54.7% were female. When glaucoma diagnosis was determined by functional damage, the AUC for US vertical CDR in the right eye was 0.882 (95% CI, 0.792 - 0.972), whereas for stereophotograph it was 0.982 (95% CI, 0.945 - 1.0). The mean difference of vertical CDR between stereophotograph and US was 0.46 (95% CI, 0.425 - 0.488), as US tended to underestimate CDR measurements greater than 0.8 on stereophotographs. Regarding MRI results, there were significant differences of ION parameters and LGN height between glaucoma and control groups. All ION segments correlated with functional parameters and OCT rim area. In addition, ION distal segments correlated with the OCT average retinal nerve fiber layer thickness, and ION segment at 15 mm behind the globe correlated with the optic nerve head rim area measured on stereophotographs. LGN measurements were not correlated with any ocular structural or functional parameter. Conclusion: 20 MHz high-resolution US may provide a useful quantitative assessment of the optic nerve head in glaucoma. This may be advantageous mainly in eyes with media opacity, in which clear optic media-based exams might not provide reliable information. However, we observed that US tended to underestimate greater CDR measurements and overestimate smaller ones in comparison with other structural tests for evaluation of the optic nerve head. Moreover, MRI may be a promising tool for objective analysis of glaucomatous damage in the central nervous system. ION correlated with functional parameters, and its distal portions correlated better with ocular structural parameters. However, LGN parameters were not associated with functional or ocular structural evaluation.