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1.
Cell ; 172(5): 1122-1131.e9, 2018 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-29474911

RESUMEN

The implementation of clinical-decision support algorithms for medical imaging faces challenges with reliability and interpretability. Here, we establish a diagnostic tool based on a deep-learning framework for the screening of patients with common treatable blinding retinal diseases. Our framework utilizes transfer learning, which trains a neural network with a fraction of the data of conventional approaches. Applying this approach to a dataset of optical coherence tomography images, we demonstrate performance comparable to that of human experts in classifying age-related macular degeneration and diabetic macular edema. We also provide a more transparent and interpretable diagnosis by highlighting the regions recognized by the neural network. We further demonstrate the general applicability of our AI system for diagnosis of pediatric pneumonia using chest X-ray images. This tool may ultimately aid in expediting the diagnosis and referral of these treatable conditions, thereby facilitating earlier treatment, resulting in improved clinical outcomes. VIDEO ABSTRACT.


Asunto(s)
Aprendizaje Profundo , Diagnóstico por Imagen , Neumonía/diagnóstico , Niño , Humanos , Redes Neurales de la Computación , Neumonía/diagnóstico por imagen , Curva ROC , Reproducibilidad de los Resultados , Tomografía de Coherencia Óptica
2.
Br Med Bull ; 146(1): 4-18, 2023 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-37100423

RESUMEN

INTRODUCTION: Integrated care is an established approach to delivery in parts of the healthcare infrastructure, and an ideal which, it is claimed, should be realized system-wide. Its ethical weight derives from its defence of a view about how healthcare ought to operate. Although the goal of integration is laudable, it is ethically and practically complex, involving trade-offs. SOURCES OF DATA: Considerable evidence attests to widespread enthusiasm for integration, given the need to prevent harm and extend the reach of scarce resources. Equally, evidence increasingly highlights the obstacles to successfully translating this ideal into practice. AREAS OF AGREEMENT: The principle that healthcare should be seamless, ensuring that patients do not come to harm through gaps in care enjoys broad agreement. There is a similar consensus that placing the patient's perspective at the centre of decision-making is vital, since this enables identification of these gaps. AREAS OF CONTROVERSY: Integrating care by making it seamless entails blurring boundaries of care domains. This risks undermining the locus of responsibility for care decisions via confusion about who has ownership of specialist knowledge where domains overlap. There is a lack of consensus about how successful integration should be measured. GROWING POINTS: More research into the relative cost-effectiveness of upstream public health investment in preventing chronic ill-health caused by modifiable lifestyle factors vs integrating care for people already ill; further research into ethical implications of integration in practice, which can be obscured by the simplicity of the fundamental normative principle guiding integration in theory.


Asunto(s)
Prestación Integrada de Atención de Salud , Humanos , Prestación Integrada de Atención de Salud/ética
3.
Camb Q Healthc Ethics ; : 1-13, 2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-37161597

RESUMEN

The risk of creating cerebral organoids/assembloids conscious enough to suffer is a recurrent concern in organoid research ethics. On one hand, we should, apparently, avoid discovering how to distinguish between organoids that it would be permissible (non-conscious) and impermissible (conscious) to use in research, since if successful we would create organoids that suffer. On the other, if we do not, the risk persists that research might inadvertently continue to cause organoids to suffer. Moreover, since modeling some brain disorders may require inducing stress in organoids, it is unclear how to eliminate the risk, if we want to develop effective therapies. We are committed to harm avoidance but hamstrung by a presumption that we should avoid research that might tell us clearly when suffering occurs. How can we negotiate this challenge and maximize the therapeutic benefits of cerebral organoid research? The author interrogates the challenge, suggesting a tentative way forward.

4.
Int J Mol Sci ; 23(7)2022 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-35409336

RESUMEN

We investigated the etiology of decreased cone-driven vision in a light damage (LD) model of retinal degeneration. To induce slow, moderate degeneration, albino rats underwent low-intensity light exposure for 10 days. Electroretinography was utilized to assess physiologic function of the rod- and cone-driven retinal function in LD and control rats. Immunohistochemistry targeting cone arrestin allowed for quantification of cone density and for comparison of the decline in function. Photoreceptor loss was quantified by outer nuclear layer thickness decreases, as observed by optical coherence tomography and histology. The LD rats showed decreased rod- and cone-driven function with partial recovery 30 days after cessation of light exposure. In addition, LD rats showed decreased cone photoreceptor densities in the central retinal region compared to control rats. Our results demonstrate that the loss of cone-driven visual function induced by light damage is at least partially due to the death of cone photoreceptors.


Asunto(s)
Células Fotorreceptoras Retinianas Conos , Degeneración Retiniana , Animales , Electrorretinografía , Ratas , Retina/patología , Células Fotorreceptoras Retinianas Conos/patología , Degeneración Retiniana/patología , Tomografía de Coherencia Óptica
5.
Sci Eng Ethics ; 28(6): 52, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-36318337

RESUMEN

The human enhancement debate has over the last few decades been concerned with ethical issues in methods for improving the physical, cognitive, or emotive states of individual people, and of the human species as a whole. Arguments in favour of enhancement defend it as a paradigm of rationality, presenting it as a clear-eyed, logical defence of what we stand to gain from transcending the typical limits of our species. If these arguments are correct, it appears that adults should in principle be able to make rational and informed decisions about enhancing themselves. In this paper, however, we suggest that a rational and informed choice to enhance oneself may in some cases be impossible. Drawing on L. A. Paul's work on 'transformative experience', we argue that some enhancements-such as certain moral or cognitive modifications-may give rise to unbridgeable epistemic gaps in key domains. Importantly, such gaps could prove to be not merely contingently unbridgeable due to a lack of information at a given moment, but radically unbridgeable, making someone in a non-enhanced state inherently unable to conceive of what it would be like to be enhanced in a particular way. Where this experience is key to understanding what values are being pursued by the enhancement itself, it may prove impossible for a person to be sufficiently informed, and to make a rational decision about whether or not to enhance herself. This poses a challenge for human enhancement proponents in general, and for transhumanists in particular.


Asunto(s)
Emociones , Principios Morales , Humanos
6.
Sci Eng Ethics ; 27(1): 9, 2021 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-33538942

RESUMEN

Data platforms represent a new paradigm for carrying out health research. In the platform model, datasets are pooled for remote access and analysis, so novel insights for developing better stratified and/or personalised medicine approaches can be derived from their integration. If the integration of diverse datasets enables development of more accurate risk indicators, prognostic factors, or better treatments and interventions, this obviates the need for the sharing and reuse of data; and a platform-based approach is an appropriate model for facilitating this. Platform-based approaches thus require new thinking about consent. Here we defend an approach to meeting this challenge within the data platform model, grounded in: the notion of 'reasonable expectations' for the reuse of data; Waldron's account of 'integrity' as a heuristic for managing disagreement about the ethical permissibility of the approach; and the element of the social contract that emphasises the importance of public engagement in embedding new norms of research consistent with changing technological realities. While a social contract approach may sound appealing, however, it is incoherent in the context at hand. We defend a way forward guided by that part of the social contract which requires public approval for the proposal and argue that we have moral reasons to endorse a wider presumption of data reuse. However, we show that the relationship in question is not recognisably contractual and that the social contract approach is therefore misleading in this context. We conclude stating four requirements on which the legitimacy of our proposal rests.


Asunto(s)
Consentimiento Informado , Principios Morales , Contratos , Humanos
7.
Camb Q Healthc Ethics ; 30(3): 479-491, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34109928

RESUMEN

Embodiment is typically given insufficient weight in debates concerning the moral status of Novel Synthetic Beings (NSBs) such as sentient or sapient Artificial Intelligences (AIs). Discussion usually turns on whether AIs are conscious or self-aware, but this does not exhaust what is morally relevant. Since moral agency encompasses what a being wants to do, the means by which it enacts choices in the world is a feature of such agency. In determining the moral status of NSBs and our obligations to them, therefore, we must consider how their corporeality shapes their options, preferences, values, and is constitutive of their moral universe. Analysing AI embodiment and the coupling between cognition and world, the paper shows why determination of moral status is only sensible in terms of the whole being, rather than mental sophistication alone, and why failure to do this leads to an impoverished account of our obligations to such NSBs.


Asunto(s)
Obligaciones Morales , Condición Moral , Cognición , Estado de Conciencia , Humanos , Principios Morales
8.
Ophthalmic Res ; 63(4): 383-391, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31910417

RESUMEN

INTRODUCTION: Microscopic details about retinal conditions can provide insight into pathological mechanisms, but these are ordinarily difficult to obtain in situ. We demonstrate how high-resolution imaging and optical modeling can be combined to reveal morphological features of a macular microcyst, offering insight into microcyst formation. OBJECTIVE: To use adaptive optics scanning laser ophthalmoscopic (AOSLO) images to track a transient retinal microcyst and derive its 3-dimensional shape. METHODS: A series of AOSLO images were gathered before, during, and after a transient retinal microcyst developed in an otherwise normal healthy 26-year-old male subject. Optical coherence tomography (OCT) independently confirmed the location of the microcyst. Optical modeling was conducted to quantify the lensing effect of the optically uniform microcyst and to determine its 3-dimensional shape. Increment threshold sensitivity, targeted within and around the microcyst, was tested to see if cone photoreceptor function was affected. RESULTS: A transient microcyst appeared as a 50 µm diameter circle in AOSLO images, localized to the inner nuclear layer. Based on image distortion of the photoreceptor mosaic, optical modeling suggests that the microcyst had the shape of an aspherical lens, distinguishable from a spherical, cylindrical, or elliptical shape, indicative of an edematous expansion of laminar tissue. The microcyst spontaneously resolved about 30 days after first discovery. No changes to the photoreceptor mosaic ensued from the presence of the microcyst, and functional testing of the photoreceptors below the microcyst indicated no loss of light sensitivity. CONCLUSIONS: Microcysts have been associated with numerous subtypes of optic nerve degeneration, including multiple sclerosis and various inherited neuropathies. This microcyst appeared in a healthy individual and resolved without intervention. Lensing effects can be used to determine microcyst shape, which cannot be resolved by OCT imaging, and to help infer etiology.


Asunto(s)
Quistes/diagnóstico , Oftalmoscopía/métodos , Imagen Óptica/métodos , Enfermedades de la Retina/diagnóstico , Adulto , Quistes/fisiopatología , Humanos , Imagenología Tridimensional/métodos , Estadios del Ciclo de Vida , Masculino , Óptica y Fotónica , Células Fotorreceptoras Retinianas Conos/fisiología , Enfermedades de la Retina/fisiopatología , Tomografía de Coherencia Óptica
9.
BMC Med Ethics ; 20(1): 42, 2019 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-31269930

RESUMEN

BACKGROUND: This paper explores ethical concerns arising in healthcare integration. We argue that integration is necessary imperative for meeting contemporary and future healthcare challenges, a far stronger evidence base for the conditions of its effectiveness is required. In particular, given the increasing emphasis at the policy level for the entire healthcare infrastructure to become better integrated, our analysis of the ethical challenges that follow from the logic of integration itself is timely and important and has hitherto received insufficient attention. METHODS: We evaluated an educational intervention which aims to improve child health outcomes by making transitions between primary to secondary care more efficient, ensuring children and parents are better supported throughout. The programme provided skills for trainee paediatricians and general practitioners (GPs) in co-designing integrated clinical services. RESULTS: The key ethical challenges of integrated care that arose from a clinical perspective are: professional identity and autonomy in an integrated working environment; the concomitant extent of professional responsibility in such an environment; and the urgent need for more evidence to be produced on which strategies for integrating at scale can be based. CONCLUSIONS: From our analysis we suggest a tentative way forward, viewed from a normative position broadly situated at the intersection of deontology and care ethics. We adopt this position because the primary clinical ethical issues in the context of integrated care concern: how to ensure that all duties of care to individual patients are met in a newly orientated working environment where clinical responsibility may be ambiguous; and the need to orientate care around the patient by foregrounding their autonomous preferences and ensuring good patient clinician relationships in clinical decision-making.


Asunto(s)
Prestación Integrada de Atención de Salud/ética , Atención Primaria de Salud/ética , Atención Secundaria de Salud/ética , Prestación Integrada de Atención de Salud/organización & administración , Humanos , Autonomía Profesional , Rol Profesional , Transición a la Atención de Adultos/ética , Transición a la Atención de Adultos/organización & administración
10.
BMC Med Educ ; 19(1): 8, 2019 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-30612565

RESUMEN

BACKGROUND: Integrated care unites funding, administrative, organisational, service delivery and clinical levels to create connectivity, alignment and collaboration within and between care delivery and prevention sectors. It aims to improve efficiency by avoiding unnecessary duplication of resources. Consequently, implementing integrated care is increasingly important; however, there are many barriers and how we teach healthcare practitioners to work across systems is under-researched. This paper explores an innovative educational curriculum, the Programme for Integrated Child Health (PICH). METHODS: The PICH involved an experiential learning approach supported by taught sessions on specific issues relevant to integrated care. A qualitative study was conducted by interviewing 23 participants using semi-structured one-to-one interviews. Participants included trainees (general practice, paediatrics) and programme mentors. Data was thematically analysed. RESULTS: Results are coded under three main themes: integrated care curriculum components, perceptions of a curriculum addressing integrated care and organisational change, and personal and professional learning. The data highlights the importance of real-world projects, utilising healthcare data, and considering patient perspectives to understand and develop integrated practices. Trainees received guidance from mentors but, more crucially learnt from, with, and about one another. They learnt about the context in which GPs and paediatricians work and developed a deeper understanding through which integrated services could be meaningfully developed. CONCLUSIONS: This study explored participants' experiences and can be taken forward by educationalists to design curricula to better prepare healthcare practitioners to work collaboratively. The emergence of integrated care brings about challenges for traditional pedagogical approaches as learners have to re-align their discipline-specific approaches with evolving healthcare structures. PICH demonstrated that trainees acquired knowledge through real-word projects and experiential learning; and that this facilitated integration, empowering doctors to become leaders of organisational change. However, there are also many challenges of implementing integrated curricula which need to be addressed, including breaking down professional silos and integrating resourceful healthcare. This study begins to demonstrate the ability of an integrated curriculum to support trainees to work collaboratively, but further work is needed to develop the wider efficacy of the programme incorporating other professional groups, and to assess its longer term impact.


Asunto(s)
Actitud del Personal de Salud , Médicos Generales/educación , Medicina Integrativa/organización & administración , Pediatras/educación , Adulto , Curriculum , Femenino , Humanos , Liderazgo , Masculino , Investigación Cualitativa , Adulto Joven
11.
Am J Bioeth ; 18(11): 43-53, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30475174

RESUMEN

Early intervention (EI) aims to identify children or families at risk of poor health, and take preventative measures at an early stage, when intervention is more likely to succeed. EI is concerned with the just distribution of "life chances," so that all children are given fair opportunity to realize their potential and lead a good life; EI policy design, therefore, invokes ethical questions about the balance of responsibilities between the state, society, and individuals in addressing inequalities. We analyze a corpus of EI policy guidance to investigate explicit and implicit ethical arguments about who should be held morally responsible for safeguarding child health and well-being. We examine the implications of these claims and explore what it would mean to put the proposed policies into practice. We conclude with some remarks about the useful role that philosophical analysis can play in EI policy development.


Asunto(s)
Defensa del Niño , Intervención Educativa Precoz/ética , Análisis Ético , Formulación de Políticas , Niño , Humanos , Reino Unido
12.
Eur J Neurosci ; 45(8): 1102-1110, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28244152

RESUMEN

Glycogen synthase kinase 3 (GSK3) is a serine-threonine kinase that regulates mammalian circadian rhythms at the behavioral, molecular and neurophysiological levels. In the central circadian pacemaker, the suprachiasmatic nucleus (SCN), inhibitory phosphorylation of GSK3 exhibits a rhythm across the 24 h day. We have recently shown that GSK3 is capable of influencing both the molecular clock and SCN neuronal activity rhythms. However, it is not known whether GSK3 regulates the response to environmental cues such as light. The goal of this study was to test the hypothesis that GSK3 activation mediates light-induced SCN excitability and photic entrainment. Immunofluorescence staining in the SCN of mice showed that late-night light exposure significantly increased GSK3 activity (decreased pGSK3ß levels) 30-60 min after the light-pulse. In addition, pharmacological inhibition of GSK3 blocked the expected light-induced excitability in SCN neurons; however, this effect was not associated with changes in resting membrane potential or input resistance. Behaviorally, mice with constitutively active GSK3 (GSK3-KI) re-entrained to a 6-h phase advance in the light-dark cycle in significantly fewer days than WT control animals. Furthermore, the behavioral and SCN neuronal activity of GSK3-KI mice was phase-advanced compared to WT, in both normal and light-exposed conditions. Finally, GSK3-KI mice exhibited normal negative-masking behavior and electroretinographic responses to light, suggesting that the enhanced photic entrainment is not due to an overall increased sensitivity to light in these animals. Taken together, these results provide strong evidence that GSK3 activation contributes to light-induced phase-resetting at both the neurophysiological and behavioral levels.


Asunto(s)
Relojes Circadianos/fisiología , Ritmo Circadiano/fisiología , Glucógeno Sintasa Quinasa 3/metabolismo , Fototransducción/fisiología , Neuronas/enzimología , Núcleo Supraquiasmático/enzimología , Potenciales de Acción/fisiología , Adaptación Fisiológica/fisiología , Animales , Femenino , Glucógeno Sintasa Quinasa 3/genética , Luz , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Actividad Motora/fisiología , Fotoperiodo , Retina/fisiología , Técnicas de Cultivo de Tejidos
13.
Health Care Anal ; 25(3): 191-211, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25716752

RESUMEN

This paper shows how critical realism can be used to integrate empirical data and philosophical analysis within 'empirical bioethics'. The term empirical bioethics, whilst appearing oxymoronic, simply refers to an interdisciplinary approach to the resolution of practical ethical issues within the biological and life sciences, integrating social scientific, empirical data with philosophical analysis. It seeks to achieve a balanced form of ethical deliberation that is both logically rigorous and sensitive to context, to generate normative conclusions that are practically applicable to the problem, challenge, or dilemma. Since it incorporates both philosophical and social scientific components, empirical bioethics is a field that is consistent with the use of critical realism as a research methodology. The integration of philosophical and social scientific approaches to ethics has been beset with difficulties, not least because of the irreducibly normative, rather than descriptive, nature of ethical analysis and the contested relation between fact and value. However, given that facts about states of affairs inform potential courses of action and their consequences, there is a need to overcome these difficulties and successfully integrate data with theory. Previous approaches have been formulated to overcome obstacles in combining philosophical and social scientific perspectives in bioethical analysis; however each has shortcomings. As a mature interdisciplinary approach critical realism is well suited to empirical bioethics, although it has hitherto not been widely used. Here I show how it can be applied to this kind of research and explain how it represents an improvement on previous approaches.


Asunto(s)
Bioética , Investigación Empírica , Teoría Ética , Análisis Ético , Humanos , Principios Morales
14.
J Physiol ; 594(7): 1841-54, 2016 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-26691896

RESUMEN

KEY POINTS: We propose that the end product of chromophore bleaching in rod photoreceptors, all-trans retinol, is part of a feedback loop that increases the sensitivity of the phototransduction cascade in rods. A previously described light-induced hypersensitivity in rods, termed adaptive potentiation, is reduced by exogenously applied all-trans retinol but not all-trans retinal. This potentiation is produced by insulin-like growth factor-1, whose binding proteins are located in the extracellular matrix, even in our isolated retina preparation after removal of the retinal pigmented epithelium. Simple modelling suggests that the light stimuli used in the present study will produce sufficient all-trans retinol within the interphotoreceptor matrix to explain the potentiation effect. ABSTRACT: Photoreceptors translate the absorption of photons into electrical signals for propagation through the visual system. Mammalian photoreceptor signalling has largely been studied in isolated cells, and such studies have necessarily avoided the complex environment of supportive proteins that surround the photoreceptors. The interphotoreceptor matrix (IPM) contains an array of proteins that aid in both structural maintenance and cellular homeostasis, including chromophore turnover. In signalling photon absorption, the chromophore 11-cis retinal is first isomerized to all-trans retinal, followed by conversion to all-trans retinol (ROL) for removal from the photoreceptor. Interphotoreceptor retinoid-binding protein (IRBP) is the most abundant protein in the IPM, and it promotes the removal of bleached chromophores and recycling in the nearby retinal pigment epithelium. By studying the light responses of isolated mouse retinas, we demonstrate that ROL can act as a feedback signal onto photoreceptors that influences the sensitivity of phototransduction. In addition to IRBP, the IPM also contains insulin-like growth factor-1 (IGF-1) and its associated binding proteins, although their functions have not yet been described. We demonstrate that extracellular application of physiological concentrations of IGF-1 can increase rod photoreceptor sensitivity in mammalian retinas. We also determine that chromophores and growth factors can limit the range of a newly described form of photoreceptor light adaptation. Finally, fluorescent antibodies demonstrate the presence of IRBP and IGFBP-3 in isolated retinas. A simple model of the formation and release of ROL into the extracellular space quantitatively describes this novel feedback loop.


Asunto(s)
Factor I del Crecimiento Similar a la Insulina/metabolismo , Fotones , Células Fotorreceptoras Retinianas Bastones/metabolismo , Umbral Sensorial , Visión Ocular , Vitamina A/metabolismo , Absorción de Radiación , Animales , Células Cultivadas , Matriz Extracelular/metabolismo , Proteínas del Ojo/metabolismo , Ratones , Ratones Endogámicos C57BL , Células Fotorreceptoras Retinianas Bastones/fisiología , Proteínas de Unión al Retinol/metabolismo
15.
Camb Q Healthc Ethics ; 30(4): 563-574, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34702405
16.
Cell Commun Signal ; 12: 67, 2014 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-25323447

RESUMEN

BACKGROUND: The rod photoreceptor cGMP-gated cation channel, consisting of three α- and one ß subunit, controls ion flow into the rod outer segment (ROS). In addition to the ß-subunit, the Cngb1 locus encodes an abundant soluble protein, GARP2 that binds stoichiometrically to rod photoreceptor cGMP phosphodiesterase type 6 (PDE6). To examine the in vivo functional role of GARP2 we generated opsin promoter-driven transgenic mice overexpressing GARP2 three-fold specifically in rod photoreceptors. RESULTS: In the GARP2 overexpressing transgenic mice (tg), the endogenous channel ß-subunit, cGMP phosphodiesterase α-subunit, peripherin2/RDS and guanylate cyclase I were present at WT levels and were properly localized within the ROS. While localized properly within ROS, two proteins cGMP phosphodiesterase α-subunit (1.4-fold) and cGMP-gated cation channel α-subunit (1.2-fold) were moderately, but significantly elevated. Normal stratification of all retinal layers was observed, and ROS were stable in numbers but were 19% shorter than WT. Analysis of the photoresponse using electroretinography (ERG) showed that tg mice exhibit no change in sensitivity indicating overall normal rod function, however two parameters of the photoresponse significantly differed from WT responses. Fitting of the rising phase of the ERG a-wave to an accepted model of phototransduction showed a two-fold increase in phototransduction gain in the tg mice. The increase in gain was confirmed in isolated retinal tissue and by suction electrode recordings of individual rod photoreceptor cells. A measure of response recovery, the dominant time constant (τD) was elevated 69% in isolated retina compared to WT, indicating slower shutoff of the photoresponse. CONCLUSIONS: GARP2 may participate in regulating visual signal transduction through a previously unappreciated role in regulating phototransduction gain and recovery.


Asunto(s)
Proteínas de la Membrana/metabolismo , Células Fotorreceptoras Retinianas Bastones/metabolismo , Animales , Electrorretinografía , Proteínas de la Membrana/genética , Ratones Endogámicos C57BL , Ratones Transgénicos , Células Fotorreceptoras Retinianas Bastones/fisiología
18.
Br J Ophthalmol ; 108(4): 536-545, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-37094835

RESUMEN

OBJECTIVE: To evaluate the role of automated optical coherence tomography (OCT) segmentation, using a validated deep-learning model, for assessing the effect of C3 inhibition on the area of geographic atrophy (GA); the constituent features of GA on OCT (photoreceptor degeneration (PRD), retinal pigment epithelium (RPE) loss and hypertransmission); and the area of unaffected healthy macula.To identify OCT predictive biomarkers for GA growth. METHODS: Post hoc analysis of the FILLY trial using a deep-learning model for spectral domain OCT (SD-OCT) autosegmentation. 246 patients were randomised 1:1:1 into pegcetacoplan monthly (PM), pegcetacoplan every other month (PEOM) and sham treatment (pooled) for 12 months of treatment and 6 months of therapy-free monitoring. Only participants with Heidelberg SD-OCT were included (n=197, single eye per participant).The primary efficacy endpoint was the square root transformed change in area of GA as complete RPE and outer retinal atrophy (cRORA) in each treatment arm at 12 months, with secondary endpoints including RPE loss, hypertransmission, PRD and intact macular area. RESULTS: Eyes treated PM showed significantly slower mean change of cRORA progression at 12 and 18 months (0.151 and 0.277 mm, p=0.0039; 0.251 and 0.396 mm, p=0.039, respectively) and RPE loss (0.147 and 0.287 mm, p=0.0008; 0.242 and 0.410 mm, p=0.00809). PEOM showed significantly slower mean change of RPE loss compared with sham at 12 months (p=0.0313). Intact macular areas were preserved in PM compared with sham at 12 and 18 months (p=0.0095 and p=0.044). PRD in isolation and intact macula areas was predictive of reduced cRORA growth at 12 months (coefficient 0.0195, p=0.01 and 0.00752, p=0.02, respectively) CONCLUSION: The OCT evidence suggests that pegcetacoplan slows progression of cRORA overall and RPE loss specifically while protecting the remaining photoreceptors and slowing the progression of healthy retina to iRORA.


Asunto(s)
Aprendizaje Profundo , Atrofia Geográfica , Humanos , Atrofia , Angiografía con Fluoresceína/métodos , Atrofia Geográfica/diagnóstico , Atrofia Geográfica/tratamiento farmacológico , Atrofia Geográfica/patología , Retina , Epitelio Pigmentado de la Retina/patología , Tomografía de Coherencia Óptica/métodos
19.
JAMA Ophthalmol ; 142(6): 548-558, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38722644

RESUMEN

Importance: Despite widespread availability and consensus on its advantages for detailed imaging of geographic atrophy (GA), spectral-domain optical coherence tomography (SD-OCT) might benefit from automated quantitative OCT analyses in GA diagnosis, monitoring, and reporting of its landmark clinical trials. Objective: To analyze the association between pegcetacoplan and consensus GA SD-OCT end points. Design, Setting, and Participants: This was a post hoc analysis of 11 614 SD-OCT volumes from 936 of the 1258 participants in 2 parallel phase 3 studies, the Study to Compare the Efficacy and Safety of Intravitreal APL-2 Therapy With Sham Injections in Patients With Geographic Atrophy (GA) Secondary to Age-Related Macular Degeneration (OAKS) and Study to Compare the Efficacy and Safety of Intravitreal APL-2 Therapy With Sham Injections in Patients With Geographic Atrophy (GA) Secondary to Age-Related Macular Degeneration (DERBY). OAKS and DERBY were 24-month, multicenter, randomized, double-masked, sham-controlled studies conducted from August 2018 to July 2020 among adults with GA with total area 2.5 to 17.5 mm2 on fundus autofluorescence imaging (if multifocal, at least 1 lesion ≥1.25 mm2). This analysis was conducted from September to December 2023. Interventions: Study participants received pegcetacoplan, 15 mg per 0.1-mL intravitreal injection, monthly or every other month, or sham injection monthly or every other month. Main Outcomes and Measures: The primary end point was the least squares mean change from baseline in area of retinal pigment epithelium and outer retinal atrophy in each of the 3 treatment arms (pegcetacoplan monthly, pegcetacoplan every other month, and pooled sham [sham monthly and sham every other month]) at 24 months. Feature-specific area analysis was conducted by Early Treatment Diabetic Retinopathy Study (ETDRS) regions of interest (ie, foveal, parafoveal, and perifoveal). Results: Among 936 participants, the mean (SD) age was 78.5 (7.22) years, and 570 participants (60.9%) were female. Pegcetacoplan, but not sham treatment, was associated with reduced growth rates of SD-OCT biomarkers for GA for up to 24 months. Reductions vs sham in least squares mean (SE) change from baseline of retinal pigment epithelium and outer retinal atrophy area were detectable at every time point from 3 through 24 months (least squares mean difference vs pooled sham at month 24, pegcetacoplan monthly: -0.86 mm2; 95% CI, -1.15 to -0.57; P < .001; pegcetacoplan every other month: -0.69 mm2; 95% CI, -0.98 to -0.39; P < .001). This association was more pronounced with more frequent dosing (pegcetacoplan monthly vs pegcetacoplan every other month at month 24: -0.17 mm2; 95% CI, -0.43 to 0.08; P = .17). Stronger associations were observed in the parafoveal and perifoveal regions for both pegcetacoplan monthly and pegcetacoplan every other month. Conclusions and Relevance: These findings offer additional insight into the potential effects of pegcetacoplan on the development of GA, including potential effects on the retinal pigment epithelium and photoreceptors. Trial Registration: ClinicalTrials.gov Identifiers: NCT03525600 and NCT03525613.


Asunto(s)
Angiografía con Fluoresceína , Atrofia Geográfica , Inyecciones Intravítreas , Tomografía de Coherencia Óptica , Agudeza Visual , Humanos , Atrofia Geográfica/diagnóstico , Atrofia Geográfica/tratamiento farmacológico , Femenino , Masculino , Anciano , Método Doble Ciego , Agudeza Visual/fisiología , Angiografía con Fluoresceína/métodos , Epitelio Pigmentado de la Retina/patología , Epitelio Pigmentado de la Retina/diagnóstico por imagen , Anciano de 80 o más Años , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Fondo de Ojo , Consenso , Resultado del Tratamiento , Estudios de Seguimiento , Inhibidores de la Angiogénesis/administración & dosificación , Inhibidores de la Angiogénesis/uso terapéutico
20.
Ophthalmol Ther ; 12(6): 3143-3158, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37715860

RESUMEN

INTRODUCTION: To evaluate the effect pegcetacoplan, a C3 and C3b inhibitor, on the rate of progression of geographic atrophy (GA) as assessed by spectral domain optical coherence tomography (SD-OCT) using a split-person study design and deep-learning quantification. METHODS: A post hoc analysis of phase 2 FILLY trial data comparing study (treated monthly, treated every other month and sham-treated) and fellow (untreated) eyes in a split-person study design was performed. This analysis included 288 eyes from 144 patients with bilateral GA from the FILLY phase 2 trial (Clinical Trials identifier: NCT02503332). Only patients with bilateral GA and without evidence of choroidal neovascularisation in either eye were included. Patient study eyes were treated with sham injections or with pegcetacoplan monthly (PM) or every other month (PEOM) for 12 months. SD-OCT scans of study and fellow eyes taken at baseline and 12 months were used for the analysis. The main outcomes were the annual change in the area of retinal pigment epithelial and outer retinal atrophy (RORA), its constituent features (photoreceptor degeneration [PRD], retinal pigment epithelium [RPE] loss, hypertransmission) and intact macula as compared to the untreated fellow eye. RESULTS: Annual GA growth was reduced in eyes treated with PM versus untreated fellow eyes for OCT features, including RORA (study eye 0.792 vs. fellow eye 1.13 mm2; P = 0.003), PRD (0.739 vs. 1.23 mm2; P = 0.015), RPE-loss (0.789 vs. 1.17 mm2; P = 0.007) and intact macula (- 0.735 vs. - 1.29 mm2; P = 0.011). Similar (but not statistically significant) trends were observed with the PEOM treatment or when GA was quantified with fundus autofluorescence (FAF). The sham treatment demonstrated no effect. Pearson correlation coefficients showed concordance in the enlargement rate of GA between the study and fellow eyes in the sham (R = 0.64) and PEOM (R = 0.68) groups, but not in the PM group (R = 0.21). CONCLUSIONS: Pegcetacoplan-treated eyes demonstrated a reduction in spatial GA progression compared to their untreated counterparts. This effect was more evident on OCT than with FAF. TRIAL REGISTRATION: Clinical Trials identifier: NCT02503332.

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