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1.
Cell Mol Life Sci ; 81(1): 301, 2024 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-39003683

RESUMEN

Voltage-gated K+ (KV) channels govern K+ ion flux across cell membranes in response to changes in membrane potential. They are formed by the assembly of four subunits, typically from the same family. Electrically silent KV channels (KVS), however, are unable to conduct currents on their own. It has been assumed that these KVS must obligatorily assemble with subunits from the KV2 family into heterotetrameric channels, thereby giving rise to currents distinct from those of homomeric KV2 channels. Herein, we show that KVS subunits indeed also modulate the activity, biophysical properties and surface expression of recombinant KV7 isoforms in a subunit-specific manner. Employing co-immunoprecipitation, and proximity labelling, we unveil the spatial coexistence of KVS and KV7 within a single protein complex. Electrophysiological experiments further indicate functional interaction and probably heterotetramer formation. Finally, single-cell transcriptomic analyses identify native cell types in which this KVS and KV7 interaction may occur. Our findings demonstrate that KV cross-family interaction is much more versatile than previously thought-possibly serving nature to shape potassium conductance to the needs of individual cell types.


Asunto(s)
Subunidades de Proteína , Humanos , Animales , Subunidades de Proteína/metabolismo , Células HEK293 , Potenciales de la Membrana , Isoformas de Proteínas/metabolismo , Isoformas de Proteínas/genética , Canales de Potasio con Entrada de Voltaje/metabolismo , Canales de Potasio con Entrada de Voltaje/genética , Canal de Potasio KCNQ1/metabolismo , Canal de Potasio KCNQ1/genética
2.
Cell Mol Life Sci ; 78(4): 1597-1613, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32728765

RESUMEN

Optogenetic strategies to restore vision in patients blind from end-stage retinal degenerations aim to render remaining retinal neurons light-sensitive. We present an innovative combination of multi-electrode array recordings together with a complex pattern-generating light source as a toolset to determine the extent to which neural retinal responses to complex light stimuli can be restored following viral delivery of red-shifted channelrhodopsin in the retinally degenerated mouse. Our data indicate that retinal output level spatiotemporal response characteristics achieved by optogenetic gene therapy closely parallel those observed for normal mice but equally reveal important limitations, some of which could be mitigated using bipolar-cell targeted gene-delivery approaches. As clinical trials are commencing, these data provide important new information on the capacity and limitations of channelrhodopsin-based gene therapies. The toolset we established enables comparing optogenetic constructs and stem-cell-based techniques, thereby providing an efficient and sensitive starting point to identify future approaches for vision restoration.


Asunto(s)
Terapia Genética , Neuronas/metabolismo , Retina/metabolismo , Degeneración Retiniana/terapia , Animales , Channelrhodopsins/genética , Channelrhodopsins/uso terapéutico , Ensayos Clínicos como Asunto , Técnicas de Transferencia de Gen/tendencias , Vectores Genéticos/uso terapéutico , Humanos , Luz , Ratones , Neuronas/patología , Optogenética , Retina/patología , Degeneración Retiniana/genética , Degeneración Retiniana/patología
3.
Exp Eye Res ; 207: 108553, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33811915

RESUMEN

PURPOSE: Retinal bipolar cells survive even in the later stages of inherited retinal degenerations (IRDs) and so are attractive targets for optogenetic approaches to vision restoration. However, it is not known to what extent the remodelling that these cells undergo during degeneration affects their function. Specifically, it is unclear if they are free from metabolic stress, receptive to adeno-associated viral vectors, suitable for opsin-based optogenetic tools and able to propagate signals by releasing neurotransmitter. METHODS: Fluorescence activated cell sorting (FACS) was performed to isolate labelled bipolar cells from dissociated retinae of litter-mates with or without the IRD mutation Pde6brd1/rd1 selectively expressing an enhanced yellow fluorescent protein (EYFP) as a marker in ON-bipolar cells. Subsequent mRNA extraction allowed Illumina® microarray comparison of gene expression in bipolar cells from degenerate to those of wild type retinae. Changes in four candidate genes were further investigated at the protein level using retinal immunohistochemistry over the course of degeneration. RESULTS: A total of sixty differentially expressed transcripts reached statistical significance: these did not include any genes directly associated with native primary bipolar cell signalling, nor changes consistent with metabolic stress. Four significantly altered genes (Srm2, Slf2, Anxa7 & Cntn1), implicated in synaptic remodelling, neurotransmitter release and viral vector entry had immunohistochemical staining colocalising with ON-bipolar cell markers and varying over the course of degeneration. CONCLUSION: Our findings suggest relatively few gene expression changes in the context of degeneration: that despite remodelling, bipolar cells are likely to remain viable targets for optogenetic vision restoration. In addition, several genes where changes were seen could provide a basis for investigations to enhance the efficacy of optogenetic therapies.


Asunto(s)
Anexina A7/genética , Contactina 1/genética , Regulación de la Expresión Génica/fisiología , Células Bipolares de la Retina/metabolismo , Degeneración Retiniana/genética , Espermidina Sintasa/genética , Sulfatasas/genética , Animales , Dependovirus/genética , Femenino , Citometría de Flujo , Vectores Genéticos , Inmunohistoquímica , Ratones , Ratones Transgénicos , Optogenética , Reacción en Cadena en Tiempo Real de la Polimerasa
4.
BMC Med Res Methodol ; 21(1): 170, 2021 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-34404346

RESUMEN

BACKGROUND: To model the progression of geographic atrophy (GA) in patients with age-related macular degeneration (AMD) by building a suitable statistical regression model for GA size measurements obtained from fundus autofluorescence imaging. METHODS: Based on theoretical considerations, we develop a linear mixed-effects model for GA size progression that incorporates covariable-dependent enlargement rates as well as correlations between longitudinally collected GA size measurements. To capture nonlinear progression in a flexible way, we systematically assess Box-Cox transformations with different transformation parameters λ. Model evaluation is performed on data collected for two longitudinal, prospective multi-center cohort studies on GA size progression. RESULTS: A transformation parameter of λ=0.45 yielded the best model fit regarding the Akaike information criterion (AIC). When hypertension and hypercholesterolemia were included as risk factors in the model, they showed an association with progression of GA size. The mean estimated age-of-onset in this model was 67.21±6.49 years. CONCLUSIONS: We provide a comprehensive framework for modeling the course of uni- or bilateral GA size progression in longitudinal observational studies. Specifically, the model allows for age-of-onset estimation, identification of risk factors and prediction of future GA size. A square-root transformation of atrophy size is recommended before model fitting.


Asunto(s)
Atrofia Geográfica , Degeneración Macular , Anciano , Atrofia , Progresión de la Enfermedad , Humanos , Persona de Mediana Edad , Estudios Prospectivos
5.
Graefes Arch Clin Exp Ophthalmol ; 259(12): 3597-3604, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34287692

RESUMEN

PURPOSE: To investigate multimodal retinal imaging characteristics including the retinal nerve fiber layer (RNFL) thickness in patients with RPGR-associated retinitis pigmentosa (RP). METHODS: This cross-sectional case-control study included 17 consecutive patients (median age, 21 years) with RPGR-associated RP who underwent retinal imaging including optical coherence tomography (OCT), short-wavelength fundus autofluorescence (AF) imaging, and RNFL scans centered on the optic disc. RNFL thickness was manually segmented and compared to clinical and imaging parameters including the transfoveal ellipsoid zone (EZ) width, the horizontal diameter of the macular hyperautofluorescent ring. RNFL thickness was compared to 17 age- and sex-matched controls. RESULTS: In patients with RPGR-associated RP, the EZ width (R2 = 0.65), the central hyperautofluorescent ring on AF images (R2 = 0.72), and visual acuity (R2 = 0.68) were negatively correlated with age. In comparison to controls, a significantly (p < 0.0001) increased global RNFL thickness was identified in RPGR-associated RP, which was, however, less pronounced in progressed disease as indicated by the EZ width or the diameter of the central hyperautofluorescent ring. CONCLUSIONS: This study describes retinal characteristics in patients with RPGR-associated RP including a pronounced peripapillary RNFL thickness compared to healthy controls. These results contribute to the knowledge about imaging biomarkers in RP, which might be of interest for therapeutic approaches such as gene replacement therapies.


Asunto(s)
Retinitis Pigmentosa , Adulto , Biomarcadores , Estudios de Casos y Controles , Estudios Transversales , Proteínas del Ojo , Humanos , Fibras Nerviosas , Retinitis Pigmentosa/diagnóstico , Tomografía de Coherencia Óptica , Adulto Joven
6.
Echocardiography ; 38(12): 2069-2076, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34845749

RESUMEN

BACKGROUND: Heart failure (HF) complicating acute coronary syndrome (ACS) is a herald of adverse outcomes. In this systematic review, we investigated the prevalence of lung ultrasound (LUS) findings and their prognostic utility among patients with ACS. METHODS: We searched the online databases PubMed, EMBASE, and Web of Science for studies (full-text articles, published in English) that used LUS in adult patients with ACS [ST-elevation myocardial infarction (STEMI), non-ST-elevation myocardial infarction (NSTEMI), and unstable angina]. RESULTS: Of 462 studies screened, five prospective, observational investigations published between 2010 and 2021 including 1087 patients met our inclusion criteria. Two studies employed 28-zone imaging protocols whereas three used eight-zone protocols. The proportion of patients with a prior HF diagnosis was ≤ 5% in all studies. The prevalence of B-lines was examined prior to or within 12 hours after coronary angiogram and reporting varied between studies due to different imaging protocols or quantification methods. A higher number of B-lines on admission was associated with an increased risk for developing symptomatic HF during the baseline hospitalization and with a higher in-hospital mortality rate using either 8 or 28-zone protocols. A higher number of B-lines at baseline was also associated with an increased risk of subsequent HF hospitalization or all-cause death. CONCLUSIONS: Pulmonary congestion by LUS performed on admission appears to be a common finding among patients hospitalized for ACS and is associated with adverse in-hospital and long-term outcomes. Further investigations using standardized LUS protocols are warranted and have the potential to improve risk stratification in ACS.


Asunto(s)
Síndrome Coronario Agudo , Síndrome Coronario Agudo/diagnóstico por imagen , Adulto , Humanos , Pulmón , Prevalencia , Pronóstico , Estudios Prospectivos
7.
Retina ; 40(12): 2343-2356, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33214501

RESUMEN

PURPOSE: To investigate the prognostic value of demographic, functional, genetic, and imaging parameters on retinal pigment epithelium atrophy progression secondary to ABCA4-related retinopathy. METHODS: Patients with retinal pigment epithelium atrophy secondary to ABCA4-related retinopathy were examined longitudinally with fundus autofluorescence imaging. Lesion area, perimeter, circularity, caliper diameters, and focality of areas with definitely decreased autofluorescence were determined. A model was used to predict the lesion enlargement rate based on baseline variables. Sample size calculations were performed to model the power in a simulated interventional study. RESULTS: Sixty-eight eyes of 37 patients (age range, 14-78 years) with a follow-up time of 10 to 100 months were included. The mean annual progression of retinal pigment epithelium atrophy was 0.89 mm. The number of atrophic areas, the retina-wide functional impairment, and the age-of-onset category constituted significant predictors for future retinal pigment epithelium atrophy growth, explaining 25.7% of the variability. By extension of a simulated study length and/or specific patient preselection based on these baseline characteristics, the required sample size could significantly be reduced. CONCLUSION: Trial design based on specific shape-descriptive factors and patients' baseline characteristics and the adaption of the trial duration may provide potential benefits in required cohort size and absolute number of visits.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/genética , Mutación/genética , Distrofias Retinianas/diagnóstico , Distrofias Retinianas/genética , Epitelio Pigmentado de la Retina/patología , Adolescente , Adulto , Anciano , Atrofia , Demografía , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Imagen Óptica , Pronóstico , Distrofias Retinianas/fisiopatología , Estudios Retrospectivos , Agudeza Visual/fisiología , Adulto Joven
8.
Retina ; 40(1): 169-180, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30300264

RESUMEN

PURPOSE: To investigate retinal sensitivity in the junctional zone of geographic atrophy (GA) secondary to age-related macular degeneration using patient-tailored perimetry grids for mesopic and dark-adapted two-color fundus-controlled perimetry. METHODS: Twenty-five eyes with GA of 25 patients (prospective, natural-history Directional Spread in Geographic Atrophy study [DSGA; NCT02051998]) and 40 eyes of 40 normal subjects were included. Patient-tailored perimetry grids were generated using annotated fundus autofluorescence data. Customized software positioned test-points along iso-hulls surrounding the GA boundary at distances of 0.43°, 0.86°, 1.29°, 2.15°, and 3.01°. The grids were used for duplicate mesopic and dark-adapted two-color (cyan and red) fundus-controlled perimetry. Age-adjusted reference-data were obtained through regression analysis of normative data followed by spatial interpolation. RESULTS: The mean sensitivity loss for mesopic testing decreased with the distance to GA (-10.3 dB [0.43°], -8.2 dB [0.86°], -7.1 dB [1.29°], -6.8 dB [2.15°], and -6.6 dB [3.01°]; P < 0.01). Dark-adapted cyan sensitivity loss exceeded dark-adapted red sensitivity loss for all iso-hulls (-14.8 vs. -11.7 dB, -13.5 vs. -10.1 dB, -12.8 vs. -9.1 dB, -11.6 vs. -8.2 dB, -10.7 vs. -8.0 dB; P < 0.01). CONCLUSION: Patient-tailored fundus-controlled perimetry grids allowed for testing of retinal function in the junctional zone of GA with high spatial resolution. A distinct decrease in mesopic sensitivity loss between 0.43° (125 µm) and 1.29° (375 µm) was observed that leveled off at more distant test-points. In proximity to the GA boundary, the results indicate that rod exceeded cone dysfunction.


Asunto(s)
Adaptación a la Oscuridad/fisiología , Atrofia Geográfica/fisiopatología , Degeneración Macular/complicaciones , Visión Mesópica/fisiología , Retina/fisiopatología , Campos Visuales/fisiología , Anciano , Anciano de 80 o más Años , Femenino , Atrofia Geográfica/etiología , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Reproducibilidad de los Resultados , Tomografía de Coherencia Óptica , Agudeza Visual , Pruebas del Campo Visual
9.
Retina ; 39(8): 1527-1540, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29781974

RESUMEN

PURPOSE: To systematically compare the prognostic value of multiple shape-descriptive factors in the natural course of the disease. METHODS: A total of 296 eyes of 201 patients (female patients 130; mean age: 72.2 ± 13.08 years) with a median follow-up of 2.38 years from 2 prospective, noninterventional natural history studies (Fundus-Autofluorescence-in-Age-related-Macular-Degeneration [clinicaltrials.gov identifier NCT00393692], Directional-Spread-in-Geographic-Atrophy [NCT02051998]) were included in the analysis. Serial fundus autofluorescence images were annotated using semiautomated image analysis software to determine the lesion area, circularity, perimeter, and caliper diameters. These variables and the fundus autofluorescence phenotype were evaluated for prediction of the future square root progression rates using linear mixed-effects models. RESULTS: For the combined model, leave-one-out cross validation on patient level (Scenario 1: previously unknown patient) resulted in a goodness-to-fit (R value) of 0.244 and leave-one-out cross validation on visit level (Scenario 2: previous observation of the patient) in a R value of 0.391. This indicated that shape-descriptive factors could explain 24.4% of the variance in geographic atrophy progression in previously unknown patients and 39.1% in patients with previous observation. CONCLUSION: These findings confirm the relevance of shape-descriptive factors and previous progression as prognostic variables for geographic atrophy progression. However, a substantial part of the remaining variation in geographic atrophy progression seems to depend on other variables, some of which are visible in optical coherence tomography.


Asunto(s)
Atrofia Geográfica/diagnóstico , Degeneración Macular/complicaciones , Anciano , Anciano de 80 o más Años , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Atrofia Geográfica/etiología , Humanos , Masculino , Persona de Mediana Edad , Imagen Óptica , Pronóstico , Estudios Prospectivos , Epitelio Pigmentado de la Retina/patología , Factores de Riesgo , Tomografía de Coherencia Óptica , Agudeza Visual
10.
Clin Exp Ophthalmol ; 47(2): 240-249, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30168640

RESUMEN

IMPORTANCE: The diagnostic accuracy of different retinal imaging modalities to detect active choroidal neovascularization (CNV) in pseudoxanthoma elasticum (PXE) is essential to enable a correct diagnosis but is currently poorly understood. BACKGROUND: Optical coherence tomography (OCT), fluorescein angiography (FA) and OCT angiography (OCT-A) are employed in daily practice, but a systematic comparison of these imaging techniques is lacking. DESIGN: Retrospective, observational study. PARTICIPANTS: Twenty patients (31 eyes) with PXE. METHODS: OCT, FA and OCT-A imaging was performed in each eye and graded separately by independent readers. MAIN OUTCOME MEASURES: Diagnostic accuracy, sensitivity and specificity to detect CNV-activity of each modality and longitudinal change of CNV size measured by OCT-A. RESULTS: OCT showed the highest diagnostic accuracy (kappa = 0.57) in comparison to OCT-A or FA (kappa = 0.39 and 0.37, respectively). OCT-A, OCT and FA showed a diagnostic sensitivity of 0.9, 0.85 and 0.6, and a diagnostic specificity of 0.45, 0.72 and 0.82, respectively. Evaluation of longitudinal OCT recordings (24 eyes) resulted in optimal sensitivity and specificity (kappa = 1.0). Although median CNV size assessed using OCT-A remained stable on longitudinal measures of seven eyes, two eyes showed a distinct increase over time despite anti-vascular endothelial growth factor treatment. CONCLUSIONS AND RELEVANCE: The systematic use of OCT, FA and OCT-A imaging can facilitate the diagnostic accuracy for detection and follow-up of CNV activity in PXE. While structural OCT is of high value, especially when longitudinal follow-up images are available, FA and OCT-A data might contribute to diagnostic accuracy in more complex cases.


Asunto(s)
Neovascularización Coroidal/diagnóstico , Seudoxantoma Elástico/diagnóstico , Adulto , Anciano , Neovascularización Coroidal/fisiopatología , Femenino , Angiografía con Fluoresceína , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Seudoxantoma Elástico/fisiopatología , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Tomografía de Coherencia Óptica , Agudeza Visual/fisiología
11.
Ophthalmology ; 124(4): 464-478, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28109563

RESUMEN

PURPOSE: To summarize the results of 2 consensus meetings (Classification of Atrophy Meeting [CAM]) on conventional and advanced imaging modalities used to detect and quantify atrophy due to late-stage non-neovascular and neovascular age-related macular degeneration (AMD) and to provide recommendations on the use of these modalities in natural history studies and interventional clinical trials. DESIGN: Systematic debate on the relevance of distinct imaging modalities held in 2 consensus meetings. PARTICIPANTS: A panel of retina specialists. METHODS: During the CAM, a consortium of international experts evaluated the advantages and disadvantages of various imaging modalities on the basis of the collective analysis of a large series of clinical cases. A systematic discussion on the role of each modality in future studies in non-neovascular and neovascular AMD was held. MAIN OUTCOME MEASURES: Advantages and disadvantages of current retinal imaging technologies and recommendations for their use in advanced AMD trials. RESULTS: Imaging protocols to detect, quantify, and monitor progression of atrophy should include color fundus photography (CFP), confocal fundus autofluorescence (FAF), confocal near-infrared reflectance (NIR), and high-resolution optical coherence tomography volume scans. These images should be acquired at regular intervals throughout the study. In studies of non-neovascular AMD (without evident signs of active or regressed neovascularization [NV] at baseline), CFP may be sufficient at baseline and end-of-study visit. Fluorescein angiography (FA) may become necessary to evaluate for NV at any visit during the study. Indocyanine-green angiography (ICG-A) may be considered at baseline under certain conditions. For studies in patients with neovascular AMD, increased need for visualization of the vasculature must be taken into account. Accordingly, these studies should include FA (recommended at baseline and selected follow-up visits) and ICG-A under certain conditions. CONCLUSIONS: A multimodal imaging approach is recommended in clinical studies for the optimal detection and measurement of atrophy and its associated features. Specific validation studies will be necessary to determine the best combination of imaging modalities, and these recommendations will need to be updated as new imaging technologies become available in the future.


Asunto(s)
Atrofia Geográfica/clasificación , Atrofia Geográfica/diagnóstico por imagen , Imagen Multimodal , Degeneración Macular Húmeda/clasificación , Degeneración Macular Húmeda/diagnóstico por imagen , Anciano , Protocolos Clínicos , Femenino , Angiografía con Fluoresceína , Humanos , Verde de Indocianina/administración & dosificación , Masculino , Imagen Óptica , Fotograbar , Epitelio Pigmentado de la Retina/patología , Tomografía de Coherencia Óptica
13.
Ophthalmologica ; 237(1): 42-54, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-27997924

RESUMEN

PURPOSE: To assess the intrasession test-retest reliability of scotopic cyan and scotopic red fundus-controlled perimetry (FCP) in normal subjects using a modified MAIA "microperimeter" (macular integrity assessment) device. METHODS: Forty-seven normal eyes of 30 subjects (aged 33.8 years) underwent duplicate mesopic (achromatic stimuli, 400-800 nm), scotopic cyan (505 nm), and scotopic red (627 nm) FCP, using a grid of 49 stimuli over 14° of the central retina. Test-retest reliability for pointwise sensitivity (PWS), stability of fixation, reaction time and test duration were analyzed using mixed-effects models. RESULTS: PWS test-retest reliability was good among all 3 types of retinal sensitivity assessments (coefficient of repeatability of 4.75 dB for mesopic, 5.26 dB for scotopic cyan, and 4.06 dB for scotopic red testing). While the mean sensitivity decreased with eccentricity for both mesopic and scotopic red testing, it was highest at 7° eccentricity for the scotopic cyan assessment (p < 0.001). CONCLUSIONS: The modified MAIA device allows for reliable scotopic FCP in normal subjects. Our findings suggest that testing of scotopic cyan sensitivity largely reflects rod function.


Asunto(s)
Adaptación a la Oscuridad/fisiología , Mácula Lútea/diagnóstico por imagen , Visión Mesópica/fisiología , Escotoma/fisiopatología , Pruebas del Campo Visual/métodos , Campos Visuales/fisiología , Adulto , Femenino , Fondo de Ojo , Humanos , Masculino , Valores de Referencia , Reproducibilidad de los Resultados , Escotoma/diagnóstico , Agudeza Visual
14.
Ophthalmologica ; 235(4): 215-24, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27089126

RESUMEN

PURPOSE: To analyze and model visual acuity (VA) in geographic atrophy (GA) secondary to age-related macular degeneration (AMD). METHODS: The course of VA was analyzed using Turnbull's estimator in 226 eyes with uni- or bilateral GA due to AMD (151 patients; mean age 74.0 ± 7.6 years; mean follow-up time 33.4 ± 23.4 months) from the natural history FAM (Fundus-Autofluorescence Imaging in AMD) study. The variables 'age at baseline', 'gender', 'lesion size', 'diagnosis of the fellow eye', 'status of the fovea', 'focality of the lesion' and 'pattern' were evaluated for effects on predicting VA using linear mixed-effects models. RESULTS: Mean VA at baseline was 0.6 (Snellen 20/80) ± 0.4 logMAR [range -0.1 to 1.8 (20/17 to hand motions)], showing an estimated mean increase of 0.181 (95% CI 0.152-0.210) and 0.256 (0.214-0.300) after 2 and 4 years of follow-up, respectively. The percentage of eyes with a loss of ≥3 lines was 34% by 2 years and 47% by 4 years. Linear mixed model analysis suggested that 65% of VA variability could be explained by the assessed predictor variables. The strongest effect was found for the 'status of the fovea' (0.69 logMAR units between 'definitively spared fovea' and 'definitive foveal involvement', p < 0.001). The second strongest effect was identified for 'total lesion size' (effects between 0.02 and 0.09 logMAR units for each mm depending on foveal involvement, p < 0.001, square root transformed values). CONCLUSIONS: These findings underscore the importance of GA lesion characteristics as these have the strongest impact on VA. Natural history data and modeling VA to other variables will be helpful for refining outcome parameters and estimating possible benefits of therapeutic interventions.


Asunto(s)
Atrofia Geográfica/diagnóstico , Degeneración Macular/diagnóstico , Retina/patología , Agudeza Visual/fisiología , Anciano , Femenino , Angiografía con Fluoresceína , Estudios de Seguimiento , Fondo de Ojo , Atrofia Geográfica/etiología , Atrofia Geográfica/fisiopatología , Humanos , Degeneración Macular/complicaciones , Degeneración Macular/fisiopatología , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Tiempo , Tomografía de Coherencia Óptica
15.
Ophthalmology ; 122(7): 1356-65, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25972258

RESUMEN

PURPOSE: To describe the directional kinetics of the spread of geographic atrophy (GA) spread in eyes with age-related macular degeneration and foveal sparing. DESIGN: Prospective, noninterventional natural history study: Fundus Autofluorescence Imaging in Age-Related Macular Degeneration (FAM; clinicaltrials.gov identifier, NCT00393692). SUBJECTS: Participants of the FAM study exhibiting foveal sparing of GA. METHODS: Eyes were examined longitudinally with fundus autofluorescence (FAF; excitation wavelength, 488 nm; emission wavelength, >500 nm) and near infrared (NIR) reflectance imaging (Spectralis HRA+OCT or HRA2; Heidelberg Engineering, Heidelberg, Germany). Areas of foveal sparing and GA were measured by 2 independent readers using a semiautomated software tool that allows for combined NIR reflectance and FAF image grading (RegionFinder; Heidelberg Engineering). A linear mixed effect model was used to model GA kinetics over time. MAIN OUTCOME MEASURE: Change of GA lesion size over time (central vs. peripheral progression). RESULTS: A total of 47 eyes of 36 patients (mean age, 73.8±7.5 years) met the inclusion criteria. Mean follow-up time was 25.2±16.9 months (range, 5.9-74.6 months). Interreader agreement for measurements of GA and foveal-sparing size were 0.995 and 0.946, respectively. Mean area progression of GA toward the periphery was 2.27±0.22 mm(2)/year and 0.25±0.03 mm(2)/year toward the center. Analysis of square root-transformed data revealed a 2.8-fold faster atrophy progression toward the periphery than toward the fovea. Faster atrophy progression toward the fovea correlated with faster progression toward the periphery in presence of marked interindividual differences. CONCLUSIONS: The results demonstrate a significantly faster centrifugal than centripetal GA spread in eyes with GA and foveal sparing. Although the underlying pathomechanisms for differential GA progression remain unknown, local factors may be operative that protect the foveal retina-retinal pigment epithelial complex. Quantification of directional spread characteristics and modeling may be useful in the design of interventional clinical trials aiming to prolong foveal survival in eyes with GA.


Asunto(s)
Fóvea Central/patología , Atrofia Geográfica/diagnóstico , Anciano , Progresión de la Enfermedad , Femenino , Angiografía con Fluoresceína , Estudios de Seguimiento , Humanos , Cinética , Masculino , Estudios Prospectivos , Agudeza Visual/fisiología
16.
BMC Ophthalmol ; 14: 12, 2014 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-24479547

RESUMEN

BACKGROUND: Ochronosis/Alkaptonuria is a tyrosine metabolism disorder where accumulation of homogentisic acid, in eye, skin, cartilage and several other connective tissues leads to a black pigmentation of the affected tissues. It is autosomal-recessive inherited in men with a frequency of 1-9/1,000,000. While it is clear that pigment deposits lead to joint destruction, renal stone formation and cardiac valvulopathy respectively, the significance of ocular findings is still unclear. We therefore aim to evaluate the frequency and clinical significance of ocular findings in ochronosis and discuss possible therapeutic options. METHODS: Systematic review of literature via Medline and Web of Science. Only case reports in English, German, French, Spanish or Italian documenting detailed ophthalmologic examination were included. RESULTS: Our search revealed 36 case reports including 40 patients. Average age at the onset of ocular signs was 40.6 years. The most frequent sign was symmetric brown sclera pigmentation present in 82.5 percent of the patients. "Oil-drops", brown pigment spots in the limbus are generally considered pathognomonic but were a little less frequent (75 percent). Vermiform pigment deposits at the level of the conjunctiva or increased conjunctival vessel diameter is also frequent. We found an increased incidence of central vein occlusion and elevated intraocular pressure going along with chamber angle hyperpigmentation. Another condition observed twice is rapid progressive astigmatism attributable to corneoscleral pigment accumulation. CONCLUSION: Our observations suggest that ocular findings are of double relevance. First, characteristic ocular findings can anticipate the time of diagnosis and second, ocular findings may complicate to various conditions putting sight at risk. Opthalmologists and general physicians should be aware of both. Therapeutic options include protein restriction, administration of high dose vitamin C or nitisonone. Evidence for all of them is limited.


Asunto(s)
Enfermedades de la Conjuntiva/etiología , Ocronosis/complicaciones , Enfermedades de la Esclerótica/etiología , Enfermedades de la Conjuntiva/diagnóstico , Enfermedades de la Conjuntiva/terapia , Humanos , Masculino , Ocronosis/diagnóstico , Enfermedades de la Esclerótica/diagnóstico , Enfermedades de la Esclerótica/terapia
17.
Ophthalmol Retina ; 8(8): 794-803, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38311207

RESUMEN

OBJECTIVE: The primary goal of this study was to determine how structural and functional parameters influence the vision-related quality of life (VRQoL) in patients suffering from geographic atrophy (GA) secondary to age-related macular degeneration. DESIGN: This study was designed as a prospective, noninterventional, natural-history study (Directional Spread in Geographic-Atrophy study, NCT02051998). SUBJECTS: The research involved 82 patients with bilateral GA. METHODS: The study examined parameters including GA location as assessed by the ETDRS grid, best-corrected visual acuity, low-luminance visual acuity (LLVA), reading acuity, and speed. These parameters were then correlated with VRQoL, which was gauged using the National Eye Institute Visual Function Questionnaire 25. The analysis method employed was the least absolute shrinkage and selection operator with linear mixed-effects models. MAIN OUTCOME MEASURES: The central parameters measured in this study encompassed GA area, VRQoL scores associated with different GA subfields, and the significance of LLVA for foveal-sparing patients. RESULTS: On average, patients showed a total GA area of 2.9 ± 1.2 mm2 in the better eye (BE) and 3.1 ± 1.3 mm2 in the worse eye. The most significant associations with VRQoL scores for distance and near activities were observed in the inner lower and inner left subfields of the BE, respectively. For patients with foveal-sparing GA, the LLVA of the BE stood out as the most influential variable across all VRQoL scales. CONCLUSIONS: The study's findings point toward the pivotal role of GA location, especially the inner lower and inner left subfields of the BE, in relation to VRQoL in GA patients. The LLVA's importance becomes even more pronounced for foveal-sparing patients. These observations highlight the need for health care professionals to better understand the association between lesion location and patient-reported outcomes. This is critical for informing treatment decisions and refining the planning of interventional trials. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.


Asunto(s)
Atrofia Geográfica , Degeneración Macular , Calidad de Vida , Tomografía de Coherencia Óptica , Agudeza Visual , Humanos , Atrofia Geográfica/diagnóstico , Atrofia Geográfica/etiología , Atrofia Geográfica/fisiopatología , Estudios Prospectivos , Masculino , Femenino , Anciano , Degeneración Macular/complicaciones , Degeneración Macular/diagnóstico , Degeneración Macular/fisiopatología , Encuestas y Cuestionarios , Tomografía de Coherencia Óptica/métodos , Anciano de 80 o más Años , Estudios de Seguimiento , Persona de Mediana Edad , Angiografía con Fluoresceína/métodos , Fondo de Ojo
18.
Int J Cardiol ; 406: 132036, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38599465

RESUMEN

BACKGROUND: Predischarge risk stratification of patients with acute heart failure (AHF) could facilitate tailored treatment and follow-up, however, simple scores to predict short-term risk for HF readmission or death are lacking. METHODS: We sought to develop a congestion-focused risk score using data from a prospective, two-center observational study in adults hospitalized for AHF. Laboratory data were collected on admission. Patients underwent physical examination, 4-zone, and in a subset 8-zone, lung ultrasound (LUS), and echocardiography at baseline. A second LUS was performed before discharge in a subset of patients. The primary endpoint was the composite of HF hospitalization or all-cause death. RESULTS: Among 350 patients (median age 75 years, 43% women), 88 participants (25%) were hospitalized or died within 90 days after discharge. A stepwise Cox regression model selected four significant independent predictors of the composite outcome, and each was assigned points proportional to its regression coefficient: NT-proBNP ≥2000 pg/mL (admission) (3 points), systolic blood pressure < 120 mmHg (baseline) (2 points), left atrial volume index ≥60 mL/m2 (baseline) (1 point) and ≥ 9 B-lines on predischarge 4-zone LUS (3 points). This risk score provided adequate risk discrimination for the composite outcome (HR 1.48 per 1 point increase, 95% confidence interval: 1.32-1.67, p < 0.001, C-statistic: 0.70). In a subset of patients with 8-zone LUS data (n = 176), results were similar (C-statistic: 0.72). CONCLUSIONS: A four-variable risk score integrating clinical, laboratory and ultrasound data may provide a simple approach for risk discrimination for 90-day adverse outcomes in patients with AHF if validated in future investigations.


Asunto(s)
Insuficiencia Cardíaca , Readmisión del Paciente , Humanos , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/diagnóstico por imagen , Insuficiencia Cardíaca/diagnóstico , Femenino , Masculino , Anciano , Readmisión del Paciente/estadística & datos numéricos , Readmisión del Paciente/tendencias , Estudios Prospectivos , Enfermedad Aguda , Anciano de 80 o más Años , Valor Predictivo de las Pruebas , Persona de Mediana Edad , Mortalidad/tendencias , Factores de Riesgo , Causas de Muerte/tendencias , Estudios de Seguimiento , Medición de Riesgo/métodos
19.
Curr Biol ; 33(3): 474-486.e5, 2023 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-36630957

RESUMEN

Photoreceptor degeneration sufficient to produce severe visual loss often spares the inner retina. This raises hope for vision restoration treatments using optogenetics or electrical stimulation, which generate a replacement light input signal in surviving neurons. The success of these approaches is dependent on the capacity of surviving circuits of the visual system to generate and propagate an appropriate visual code in the face of neuroanatomical remodeling. To determine whether retinally degenerate animals possess this capacity, we generated a transgenic mouse model expressing the optogenetic actuator ReaChR in ON bipolar cells (second-order neurons in the visual projection). After crossing this with the rd1 model of photoreceptor degeneration, we compared ReaChR-derived responses with photoreceptor-driven responses in wild-type (WT) mice at the level of retinal ganglion cells and the visual thalamus. The ReaChR-driven responses in rd1 animals showed low photosensitivity, but in other respects generated a visual code that was very similar to the WT. ReaChR rd1 responses had high trial-to-trial reproducibility and showed sensitivity normalization to code contrast across background intensities. At the single unit level, ReaChR-derived responses exhibited broadly similar variations in response polarity, contrast sensitivity, and temporal frequency tuning as the WT. Units from the WT and ReaChR rd1 mice clustered together when subjected to unsupervised community detection based on stimulus-response properties. Our data reveal an impressive ability for surviving circuitry to recreate a rich visual code following advanced retinal degeneration and are promising for regenerative medicine in the central nervous system.


Asunto(s)
Degeneración Retiniana , Ratones , Animales , Degeneración Retiniana/terapia , Reproducibilidad de los Resultados , Retina , Células Ganglionares de la Retina/fisiología , Visión Ocular , Ratones Transgénicos
20.
medRxiv ; 2023 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-37790350

RESUMEN

Background/Aims: The primary objective was to determine how structural and functional parameters influence the vision-related quality of life (VRQoL) in patients with geographic atrophy (GA) secondary to age-related macular degeneration (AMD). Methods: This prospective, non-interventional, natural-history 'Directional Spread in Geographic-Atrophy' study was conducted at the University Eye Hospital in Bonn, enrolling 82 patients with bilateral GA. Parameters such as GA location (assessed by the Early Treatment Diabetic Retinopathy Study grid), best-corrected visual acuity (BCVA), low-luminance visual acuity (LLVA), reading acuity, and speed were examined. The association between these parameters and VRQoL, as gauged using the National Eye Institute Visual Function Questionnaire 25 (NEI VFQ-25), was analyzed through least absolute shrinkage and selection operator with linear mixed-effects models. Results: The average total GA area observed was 2.9 ± 1.2 mm2 (better eye) and 3.1 ± 1.3 mm2 (worse eye). The VRQoL scores for distance and near activities were most associated with the inner lower and inner left subfields of the better eye. For foveal-sparing patients, the LLVA of the better eye was the predominant determinate impacting all VRQoL scales. Conclusion: GA location, specifically the inner lower and inner left subfields of the better eye, has a notable effect on VRQoL in GA patients. LLVA stands out as especially vital in foveal-sparing patients, underscoring the importance for clinicians to incorporate considerations of GA location and functional parameters into their risk-benefit assessments for emerging treatments.

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