Background: Primary open-angle glaucoma patients exhibit widespread white matter degeneration throughout their visual pathways. Whether this degeneration starts at the pre- or post-geniculate pathways remains unclear. In this longitudinal study, we assess the progression of WM degeneration exhibited by the pre-geniculate optic tracts and the post-geniculate optic radiations of POAG patients over time, aiming to determine the source and pattern of spread of this degeneration.Methods: Diffusion-weighted MRI scans were acquired for 12 POAG patients and 14 controls at two time-points (...) 5.4 ± 2.1 years apart. Fiber density, an estimate of WM axonal density, was computed for the OTs and ORs of all participants in an unbiased longitudinal population template space. First, FD was compared between POAG patients and the controls at time-point 1 and time-point 2 independently. Secondly, repeated measures analysis was performed for FD change in POAG patients between the two time-points. Finally, we compared the rate of FD change over time between the two groups.Results: Compared to the controls, POAG patients exhibited significantly lower FD in the left OT at TP1 and in both OTs and the left OR at TP2. POAG patients showed a significant loss of FD between the time-points in the right OT and both ORs, while the left OR showed a significantly higher rate of FD loss in POAG patients compared to the controls.Conclusions: We find longitudinal progression of neurodegenerative WM changes in both the pre- and post-geniculate visual pathways of POAG patients. The pattern of changes suggests that glaucomatous WM degeneration starts at the pre-geniculate pathways and then spreads to the post-geniculate pathways. Furthermore, we find evidence that the trans-synaptic spread of glaucomatous degeneration to the post-geniculate pathways is a prolonged process which continues in the absence of detectable pre-geniculate degenerative progression. This suggests the presence of a time window for salvaging intact post-geniculate pathways, which could prove to be a viable therapeutic target in the future. (shrink)

Background The significance of medical implants goes beyond technical functioning and reaches into everyday life, with consequences for individuals as well as society. Ethical aspects associated with the everyday use of implants are relevant for individuals’ lifeworlds and need to be considered in implant care and in the course of technical developments. Methods This scoping review aimed to provide a synthesis of the existing evidence regarding ethically relevant psychosocial and cultural aspects in cochlear, glaucoma and cardiovascular implants in patient-centered (...) empirical research. Systematic literature searches were conducted in EBSCOhost, Philpapers, PsycNET, Pubmed, Web of Science and BELIT databases. Eligible studies were articles in German or English language published since 2000 dealing with ethically relevant aspects of cochlear, glaucoma and passive cardiovascular implants based on empirical findings from the perspective of (prospective) implant-wearers and their significant others. Following a descriptive-analytical approach, a data extraction form was developed and relevant data were extracted accordingly. We combined a basic numerical analysis of study characteristics with a thematically organized narrative synthesis of the data. Results Sixty-nine studies were included in the present analysis. Fifty were in the field of cochlear implants, sixteen in the field of passive cardiovascular implants and three in the field of glaucoma implants. Implant-related aspects were mainly found in connection with autonomy, freedom, identity, participation and justice, whereas little to no data was found with regards to ethical principles of privacy, safety or sustainability. Conclusions Empirical research on ethical aspects of implant use in everyday life is highly relevant, but marked by ambiguity and unclarity in the operationalization of ethical terms and contextualization. A transparent orientation framework for the exploration and acknowledgment of ethical aspects in “lived experiences” may contribute to the improvement of individual care, healthcare programs and research quality in this area. Ethics-sensitive care requires creating awareness for cultural and identity-related issues, promoting health literacy to strengthen patient autonomy as well as adjusting healthcare programs accordingly. More consideration needs to be given to sustainability issues in implant development and care according to an approach of ethics-by-design. (shrink)

Early and accurate diagnosis of glaucoma is critical for avoiding human vision deterioration and preventing blindness. A deep-neural-network model has been developed for the diagnosis of glaucoma based on Heidelberg retina tomography, called “Seeking Common Features and Reserving Differences Net” to make full use of the HRT data. In this work, the proposed SCRD-Net model achieved an area under the curve of 94.0%. For the two HRT image modalities, the model sensitivities were 91.2% and 78.3% at specificities of (...) 0.85 and 0.95, respectively. These results demonstrate a significant improvement over earlier results. In addition, we visualized the network outputs to develop an interpretation of the learned mechanism for discriminating glaucoma and normal images. Thus, the SCRD-Net can be an effective diagnostic indicator of glaucoma during clinical screening. To facilitate SCRD-Net utilization by the scientific community, the code implementation will be made publicly available. (shrink)

PurposeThe primary angle-closure glaucoma is an irreversible blinding eye disease in the world. Previous neuroimaging studies demonstrated that PACG patients were associated with cerebral changes. However, the effect of optic atrophy on local and remote brain functional connectivity in PACG patients remains unknown.Materials and MethodsIn total, 23 patients with PACG and 23 well-matched Health Controls were enrolled in our study and underwent resting-state functional magnetic resonance imaging scanning. The regional homogeneity method and functional connectivity method were used to evaluate (...) the local and remote brain functional connectivity. Moreover, support vector machine method was applied to constructing PACG classification model.ResultsCompared with the HC, PACG patients showed increased ReHo values in right cerebellum _8, left CER_4-5, and right CER_8. In contrast, PACG patients showed decreased ReHo values in the bilateral lingual gyrus /calcarine /superior occipital gyrus and right postcentral gyrus. The ReHo value exhibited an accuracy of 91.30% and area under curve of 0.95 for distinguishing the PACG patients from HC.ConclusionOur study demonstrated that the PACG patients showed abnormal ReHo value in the cerebellum, visual cortex, and supplementary motor area, which might be reflect the neurological mechanisms underlying vision loss and eye pain in PACG patients. Moreover, the ReHo values can be used as a useful biomarker for distinguishing the PACG patients from HCs. (shrink)

Optic neuropathies are conditions that cause disease to the optic nerve, and can result in loss of visual acuity and/or visual field defects. An improved understanding of how these conditions affect the entire visual system is warranted, to better predict and/or restore the visual loss. In this article, we review visually-driven functional magnetic resonance imaging (fMRI) studies of optic neuropathies, including glaucoma and optic neuritis (ON); we also discuss traumatic optic neuropathy (TON). Optic neuropathy-related vision loss results in fMRI (...) deficit within the visual cortex, and is often strongly correlated with clinical severity measures. Using predominantly flickering checkerboard stimuli, glaucoma studies indicated retinotopic-specific cortical alteration with more prominent deficits in advanced than in early glaucoma. Some glaucoma studies indicate a reorganized visual cortex. ON studies have indicated that the impacted cortical areas are briefly hyperactive. For ON, brain deficits are greater in the acute stages of the disease, followed by (near) normalization of responses of the LGN, visual cortex, and the dorsal visual stream, but not the ventral extrastriate cortex. Visually-driven fMRI is sensitive, at least in ON, in discriminating patients from controls, as well as the affected eye from the fellow eye within patients. The use of a greater variety of stimuli beyond checkerboards (e.g., visual motion and object recognition) in recent ON studies is encouraging, and needs to continue to disentangle the results in terms of change over time. Finally, visually-driven fMRI has not yet been applied in TON, although preliminary efforts suggest it may be feasible. Future fMRI studies of optic neuropathies should consider using more complex visual stimuli, and inter-regional analysis methods including functional connectivity. We suggest that a more systematic longitudinal comparison of optic neuropathies with advanced fMRI would provide improved diagnostic and prognostic information. (shrink)

Optic neuropathy refers to disease of the optic nerve and can result in loss of visual acuity and/or visual field defects. Combining findings from multiple fMRI modalities can offer valuable information for characterizing and managing optic neuropathies. In this article, we review a subset of resting-state functional magnetic resonance imaging (RS-fMRI) studies of optic neuropathies. We consider glaucoma, acute optic neuritis (ON), discuss traumatic optic neuropathy (TON), and explore consistency between findings from RS and visually driven fMRI studies. Consistent (...) with visually driven studies, glaucoma studies at rest also indicated reduced activation in the visual cortex and dorsal visual stream. RS-fMRI further reported varying levels of functional connectivity in the ventral stream depending on disease severity. ON patients show alterations within the visual cortex in both fMRI techniques. Particularly, higher-than-normal RS activity is observed in the acute phase and decreases as the disease progresses. A similar pattern is observed in the visual cortex of TON-like, open globe injury (OGI), patients. Additionally, visually driven and RS-fMRI studies of ON patients show recovery of brain activity in the visual cortex. RS-fMRI suggests recovery of signals in higher-tier visual areas MT and LOC as well. Finally, RS-fMRI has not yet been applied to TON, although reviewing OGI studies suggests that it is feasible. Future RS-fMRI studies of optic neuropathies could prioritize studying the fine scale RS activity of brain areas that visually driven studies have identified. We suggest that a more systematic longitudinal comparison of optic neuropathies with advanced fMRI would provide improved diagnostic and prognostic information. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Living with Blindness and Fibromyalgia while Occupying AgingKatherine SchneiderI’m blind from birth and in middle age developed fibromyalgia. I’ve retired from a thirty year career as a clinical psychologist and am working on my third book tentatively titled “Occupying Aging: Delights, Disabilities and Daily Life.” My relationship with medical professionals includes gratitude (without good care I would not be alive) and also frustration for assumptions often made about my (...) abilities. I write from the perspectives of an impatient patient, woman living in the United States, former provider of mental health services, person with both invisible and visible disabilities, and boomer moving into the world of the aged. My stories are mine of course, but when I swap medical stories with blind friends, similar happenings abound.When my mom fell down the stairs at a friend’s house, five months pregnant with me, she was told to go to bed for the next four months to save the pregnancy. Thus began the impact of health care professionals on me. I was born a month premature and spent my first month in an incubator. In 1949 it wasn’t known that the enriched oxygen atmosphere in an incubator would cause blindness. At least one lawsuit was filed against physicians and a hospital by a person blinded in this way. A large out–of–court settlement was received. The way I look at it, the health care community did the best they knew and without enough oxygen, I would have died.Early in my life, my parents took me to several ophthalmologists to see what could be done for my vision. Family folklore has it that I could smell a hospital as we entered and would begin howling. These early traumatic experiences may have led to my current healthy lifestyle so I don’t have to go to doctors much now. By about age five, it was clear that nothing could be done about my vision. For the next twenty years my forays into the health care system were for tonsillitis, sprains, and the usual childhood ills.In my early twenties, I developed acute glaucoma in one eye—caused, I’m convinced, by birth control pills. In seeking treatment for this condition, I encountered the first truly insensitive physician I’d met, who said, “Your eyes aren’t doing you any good; let’s take them out.” I was horrified! They were my eyes. I was attached to them, psychologically as well as physically. It turned out that a simple operation relieved the pressure and allowed me to keep my eyes. True, they are not the best looking big brown eyes around, but they did come with the package.Life with blindness seemed quite straightforward until my early forties, when I developed extreme fatigue and pain all over. I was worried. I knew a blind woman who had developed multiple sclerosis and I admired her, but I did not want to walk in her brave footsteps. Then a college student came to see me with the same symptoms and said that she had recently been diagnosed with fibromyalgia. I am often very empathetic with people’s concerns, but this time she complimented me by saying, “You’re great! You seem to know just how I feel.” I sagely counseled her about portioning out her energy carefully, prioritizing, using short cuts, and taking elevators when possible. Being an adult [End Page 216] student used to overachieving, she did not like what I was saying, but said she’d try to follow my advice because she could no longer do it all.What finally broke through my own denial was the day coiling up a hose and dragging it to the basement for the winter took me an hour. It left me totally exhausted and I figured that even being middle aged couldn’t account for feeling that awful.After a thorough physical and plenty of blood work to rule out Lyme disease and multiple sclerosis, I was diagnosed with fibromyalgia and placed on low doses of antidepressants to help me sleep through the night. The medication worked and I began to feel like myself again. My battle to accept that... (shrink)

Las personas dedicadas a otorgar servicios de la salud tienen el compromiso legal, ético, profesional y humano de velar por la salud y el bienestar de la sociedad. Un médico no sólo debe formarse en el ámbito académico y técnico, también debe construir y trabajar en su ética profesional. La actualización médica continua en medicina basada en evidencia y el continuo adiestramiento en el área práctica y clínica, si bien son de suma importancia, deben ir de la mano con la (...) aplicación de los principios éticos tales como el respeto por la autonomía, la beneficencia, no maleficencia al paciente y la justicia. El análisis de casos clínicos reales a la luz de la ética es un ejercicio muy enriquecedor para trascender en nuestra práctica diaria. No solamente es de gran ayuda para detectar y prevenir conductas que pudieran vulnerar o atentar contra la dignidad de los pacientes, sino para reafirmar el valor y la centralidad de la persona humana en el abordaje médico. (shrink)

This article is concerned with the history and current state of research activities into medical expert systems (MES) in Japan. A brief review of expert systems' work over the last ten years is provided and here is a discussion on future directions of artificial intelligence (AI) applications in medicine, which we expect the Japanese AI community in medicine (AIM) to undertake.