Person: Ramírez Toraño, Federico
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First Name
Federico
Last Name
Ramírez Toraño
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Psicología
Department
Psicología Experimental, Procesos Cognitivos y Logopedia
Area
Identifiers
5 results
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Item Foveal Avascular Zone and Choroidal Thickness Are Decreased in Subjects with Hard Drusen and without High Genetic Risk of Developing Alzheimer’s Disease(Biomedicines, 2021) López Cuenca, Inés; Hoz Montañana, María Rosa de; Alcántara Rey, Celia; García Martín, Elena Salobrar; Elvira Hurtado, Lorena; Fernández Albarral, José Antonio; Barabash, Ana; Ramírez Toraño, Federico; Frutos Lucas, Jaisalmer de; Salazar Corral, Juan José; Ramírez Sebastián, Ana Isabel; Ramirez Sebastian, Jose ManuelA family history (FH+) of Alzheimer’s disease (AD) and ε4 allele of the ApoE gene are the main genetic risk factors for developing AD, whereas ε4 allele plays a protective role in age-related macular degeneration. Ocular vascular changes have been reported in both pathologies. We analyzed the choroidal thickness using optical coherence tomography (OCT) and the foveal avascular zone (FAZ) using OCT-angiography and compared the results with ApoE gene expression, AD FH+, and the presence or absence of hard drusen (HD) in 184 cognitively healthy subjects. Choroidal thickness was statistically significantly different in the (FH−, ε4−, HD+) group compared with (i) both the (FH−, ε4−, HD−) and the (FH+, ε4+, HD+) groups in the superior and inferior points at 1500 µm, and (ii) the (FH+, ε4−, HD+) group in the superior point at 1500 µm. There were statistically significant differences in the superficial FAZ between the (FH+, ε4−, HD+) group and (i) the (FH+, ε4−, HD−) group and (ii) the (FH+, ε4+, HD−) group. In conclusion, ocular vascular changes are not yet evident in participants with a genetic risk of developing AD.Item Characterization of Retinal Drusen in Subjects at High Genetic Risk of Developing Sporadic Alzheimer’s Disease: An Exploratory Analysis(Journal of Personalized Medicine, 2022) López Cuenca, Inés; García Martín, Elena Salobrar; Gil Salgado, Inés; Sánchez Puebla, Lídia; Elvira Hurtado, Lorena; Fernández Albarral, José Antonio; Ramírez Toraño, Federico; Barabash, Ana; Frutos Lucas, Jaisalmer de; Salazar Corral, Juan José; Ramirez Sebastian, Jose Manuel; Ramírez Sebastián, Ana Isabel; Hoz Montañana, María Rosa deHaving a family history (FH+) of Alzheimer’s disease (AD) and being a carrier of at least one ɛ4 allele of the ApoE gene are two of the main risk factors for the development of AD. AD and age-related macular degeneration (AMD) share one of the main risk factors, such as age, and characteristics including the presence of deposits (Aβ plaques in AD and drusen in AMD); however, the role of apolipoprotein E isoforms in both pathologies is controversial. We analyzed and characterized retinal drusen by optical coherence tomography (OCT) in subjects, classifying them by their AD FH (FH- or FH+) and their allelic characterization of ApoE ɛ4 (ApoE ɛ4- or ApoE ɛ4+) and considering cardiovascular risk factors (hypercholesterolemia, hypertension, and diabetes mellitus). In addition, we analyzed the choroidal thickness by OCT and the area of the foveal avascular zone with OCTA. We did not find a relationship between a family history of AD or any of the ApoE isoforms and the presence or absence of drusen. Subjects with drusen show choroidal thinning compared to patients without drusen, and thinning could trigger changes in choroidal perfusion that may give rise to the deposits that generate drusenItem Retinal Vascular Study Using OCTA in Subjects at High Genetic Risk of Developing Alzheimer’s Disease and Cardiovascular Risk Factors(Journal of Clinical Medicine, 2022) López Cuenca, Inés; García Martín, Elena Salobrar; Sánchez Puebla, Lídia; Espejel Checa, Eva; García del Arco, Lucía; Rojas Lozano, Pilar; Elvira Hurtado, Lorena; Fernández Albarral, José Antonio; Ramírez Toraño, Federico; Barabash, Ana; Salazar Corral, Juan José; Ramirez Sebastian, Jose Manuel; Hoz Montañana, María Rosa de; Ramírez Sebastián, Ana IsabelIn 103 subjects with a high genetic risk of developing Alzheimer’s disease (AD), family history (FH) of AD and ApoE ɛ4 characterization (ApoE ɛ4) were analyzed for changes in the retinal vascular network by OCTA (optical coherence tomography angiography), and AngioTool and Erlangen-Angio-Tool (EA-Tool) as imaging analysis software. Retinal vascularization was analyzed by measuring hypercholesterolemia (HCL) and high blood pressure (HBP). Angio-Tool showed a statistically significant higher percentage of area occupied by vessels in the FH+ ApoE ɛ4- group vs. in the FH+ ApoE ɛ4+ group, and EA-Tool showed statistically significant higher vascular densities in the C3 ring in the FH+ ApoE ɛ4+ group when compared with: i)FH- ApoE ɛ4- in sectors H3, H4, H10 and H11; and ii) FH+ ApoE ɛ4- in sectors H4 and H12. In participants with HCL and HBP, statistically significant changes were found, in particular using EA-Tool, both in the macular area, mainly in the deep plexus, and in the peripapillary area. In conclusion, OCTA in subjects with genetic risk factors for the development of AD showed an apparent increase in vascular density in some sectors of the retina, which was one of the first vascular changes detectable. These changes constitute a promising biomarker for monitoring the progression of pathological neuronal degeneration.Item The relationship between retinal layers and brain areas in asymptomatic first-degree relatives of sporadic forms of Alzheimer’s disease: an exploratory analysis(Alzheimer's Research & Therapy, 2022) López Cuenca, Inés; Marcos Dolado, Alberto; Yus Fuertes, Miguel; García Martín, Elena Salobrar; Elvira Hurtado, Lorena; Fernández Albarral, José Antonio; Salazar Corral, Juan José; Ramírez Sebastián, Ana Isabel; Sánchez Puebla, Lídia; Fuentes Ferrer, Manuel Enrique; Barabash, Ana; Ramírez Toraño, Federico; Gil Martínez, Lidia; Arrazola García, Juan Lorenzo; Gil Gregorio, Pedro; Hoz Montañana, María Rosa de; Ramirez Sebastian, Jose ManuelBackground: Two main genetic risks for sporadic Alzheimer’s disease (AD) are a family history and ɛ4 allele of apolipoprotein E. The brain and retina are part of the central nervous system and share pathophysiological mechanisms in AD. Methods: We performed a cross-sectional study with 30 participants without a family history of sporadic AD (FH−) and noncarriers of ApoE ɛ4 (ApoE ɛ4−) as a control group and 34 participants with a family history of sporadic AD (FH+) and carriers of at least one ɛ4 allele (ApoE ɛ4+). We analyzed the correlations between macular volumes of retinal layers and thickness of the peripapillary retinal nerve fiber layer (pRNFL) measured by optical coherence tomography (OCT) with the brain area parameters measured by magnetic resonance imaging (MRI) in participants at high genetic risk of developing AD (FH+ ApoE ɛ4+). Results: We observed a significant volume reduction in the FH+ ApoE ɛ4+ group compared with the control group in some macular areas of (i) macular RNFL (mRNFL), (ii) inner plexiform layer (IPL), (iii) inner nuclear layer (INL), and (iv) outer plexiform layer (OPL). Furthermore, in the FH+ ApoE ɛ4+ group, the retinal sectors that showed statistically significant volume decrease correlated with brain areas that are affected in the early stages of AD. In the same group, the peripapillary retinal nerve fiber layer (pRNFL) did not show statistically significant changes in thickness compared with the control group. However, correlations of these sectors with the brain areas involved in this disease were also found. Conclusions: In cognitively healthy participants at high genetic risk of developing sporadic forms of AD, there are significant correlations between retinal changes and brain areas closely related to AD such as the entorhinal cortex, the lingual gyrus, and the hippocampus.Item Early visual alterations in individuals at-risk of Alzheimer’s disease: a multidisciplinary approach(Alzheimer's Research & Therapy, 2023) López Cuenca, Inés; Nebreda Pérez, Alberto; García Colomo, Alejandra; García Martín, Elena Salobrar; Frutos Lucas, Jaisalmer de; Bruña Fernández, Ricardo; Ramírez Sebastián, Ana Isabel; Ramírez Toraño, Federico; Salazar Corral, Juan José; Barabash, Ana; Gil, Pedro; Maestú Unturbe, Fernando; Ramirez Sebastian, Jose Manuel; Hoz Montañana, Rosa deBackground: The earliest pathological features of Alzheimer’s disease (AD) appear decades before the clinical symptoms. The pathology affects the brain and the eye, leading to retinal structural changes and functional visual alterations. Healthy individuals at high risk of developing AD present alterations in these ophthalmological measures, as well as in resting-state electrophysiological activity. However, it is unknown whether the ophthalmological alterations are related to the visual-related electrophysiological activity. Elucidating this relationship is paramount to understand the mechanisms underlying the early deterioration of the system and an important step in assessing the suitability of these measures as early biomarkers of disease. Methods: In total, 144 healthy subjects: 105 with family history of AD and 39 without, underwent ophthalmologic analysis, magnetoencephalography recording, and genotyping. A subdivision was made to compare groups with less demographic and more risk differences: 28 high-risk subjects (relatives/APOEɛ4 +) and 16 low-risk (non-relatives/APOEɛ4 −). Differences in visual acuity, contrast sensitivity, and macular thickness were evaluated. Correlations between each variable and visual-related electrophysiological measures (M100 latency and time–frequency power) were calculated for each group. Results: High-risk groups showed increased visual acuity. Visual acuity was also related to a lower M100 latency and a greater power time–frequency cluster in the high-risk group. Low-risk groups did not show this relationship. High-risk groups presented trends towards a greater contrast sensitivity that did not remain significant after correction for multiple comparisons. The highest-risk group showed trends towards the thinning of the inner plexiform and inner nuclear layers that did not remain significant after correction. The correlation between contrast sensitivity and macular thickness, and the electrophysiological measures were not significant after correction. The difference between the high- and low- risk groups correlations was no significant. Conclusions: To our knowledge, this paper is the first of its kind, assessing the relationship between ophthalmological and electrophysiological measures in healthy subjects at distinct levels of risk of AD. The results are novel and unexpected, showing an increase in visual acuity among high-risk subjects, who also exhibit a relationship between this measure and visual-related electrophysiological activity. These results have not been previously explored and could constitute a useful object of research as biomarkers for early detection and the evaluation of potential interventions’ effectiveness.