RESUMEN
Blood leakage from the vessels in the eye is the hallmark of many vascular eye diseases. One of the preclinical mouse models of retinal blood leakage, the very-low-density-lipoprotein receptor deficient mouse (Vldlr-/-), is used for drug screening and mechanistic studies. Vessel leakage is usually examined using Fundus fluorescein angiography (FFA). However, interpreting FFA images of the Vldlr-/- model is challenging as no automated and objective techniques exist for this model. A pipeline has been developed for quantifying leakage intensity and area including three tasks: (i) blood leakage identification, (ii) blood vessel segmentation, and (iii) image registration. Morphological operations followed by log-Gabor quadrature filters were used to identify leakage regions. In addition, a novel optic disk detection algorithm based on graph analysis was developed for registering the images at different timepoints. Blood leakage intensity and area measured by the methodology were compared to ground truth quantifications produced by two annotators. The relative difference between the quantifications from the method and those obtained from ground truth images was around 10% ± 6% for leakage intensity and 17% ± 8% for leakage region. The Pearson correlation coefficient between the method results and the ground truth was around 0.98 for leakage intensity and 0.94 for leakage region. Therefore, we presented a computational method for quantifying retinal vascular leakage and vessels using FFA in a preclinical angiogenesis model, the Vldlr-/- model.
Asunto(s)
Angiografía con Fluoresceína , Neovascularización Retiniana/diagnóstico por imagen , Neovascularización Retiniana/patología , Vasos Retinianos/patología , Tomografía de Coherencia Óptica , Algoritmos , Animales , Modelos Animales de Enfermedad , Angiografía con Fluoresceína/métodos , Humanos , Procesamiento de Imagen Asistido por Computador , Ratones , Ratones Noqueados , Tomografía de Coherencia Óptica/métodosRESUMEN
We conducted retinal neovascularization under subfoveal fibrotic nodule for Coats disease by using optic coherence tomography-angiography before and after ranibizumab treatment. Our patient was an 8-year-old boy who was referred with suspicious left retinal mass. His visual acuity was 20/400 in the left eye and 20/20 in the right eye at the time of admission. Posterior segment evaluation of the left eye revealed telengiectatic vessels at the inferotemporal region of the peripheral retina with hard exudates around the optic disc and macula typical for Coats disease. His optic coherence tomography revealed a subfoveal fibrotic nodule after ranibizumab injections and laser photocoagulation treatment. The optic coherence tomography-angiography results revealed neovascularization under the subfoveal nodule at the superficial vascular complex layer. After 3 intravitreal ranibizumab injections, his neovascularization regressed on optic coherence tomography-angiography and his visual acuity improved. To the best of our knowledge, this is the first report demonstrating neovascularization under the subfoveal fibrotic nodule in Coats disease on the basis of comparative with the help of optic coherence tomography-angiography before and after the treatment.