ENTRIES A–Z
Philip Winn in Dictionary of Biological Psychology, 2003
(from Latin, imago: image) An image is generally conceived of as a REPRESENTATION, and IMAGERY as the product of the imagination. In psychology however it is important to distinguish clearly between different uses of the word 'image'. The term RETINAL IMAGE refers to the pattern of light impinging on the RETINA: this is a physical representation of the visual world on the retina. The term MENTAL IMAGERY refers to a conscious recollection (see CONSCIOUSNESS) of a previous perception in the absence of the physical stimuli that produced that perception (regardless of sensory modality). Images are things that can be discriminated into two different classes: physical representations and non-physical representations (at least in so far as the neural basis of these conscious, 'stimulus free' recollections cannot be specified). It is helpful therefore to use a qualifier before the terms image or imagery to make clear what is meant by their use in any given context.
Level Set Methods in Segmentation of SDOCT Retinal Images
Ayman El-Baz, Jasjit S. Suri in Level Set Method in Medical Imaging Segmentation, 2019
As shown in Figure 5.2, the retina is a ten layered structure, viz., Nerve fiber layer (NFL), Ganglion cell layer (GCL), Inner plexiform layer (IPL), inner nuclear layer (INL), outer plexiform layer (OPL), outer nuclear layer (ONL), External limiting membrane (ELM), Ellipsoid zone (previously referred to as the IS/OS junction), Interdigitation zone, and Retinal pigment epithelium (RPE). Automatic detection of diabetic maculopathy from SDOCT retinal images is extremely important in analyzing the stage of diabetic retinopathy. Diabetic maculopathy is the condition of fluid being accumulated in between the retinal layers. As shown in Figure 5.3, SDOCT images provide more details about the intraretinal fluid and subretinal fluid present in the macula scan images.
Impact of Retinal Stimulation on Neuromodulation
Yu Chen, Babak Kateb in Neurophotonics and Brain Mapping, 2017
The basic concept outlined in the pioneering work of A.M. Skeffington, O.D., in the mid-twentieth century, refers to a hierarchy of “Where am I?,” “Where is it?,” and “What is it?” pathways, culminating in an emergent concept of vision that gives meaning to sensory signals (Skeffington 1957, Skeffington 1966). Optometrist Jacob Liberman’s 1990 book Light: The Medicine of the Future added pineal gland activation by retinal stimulation—a “How am I?” pathway to Skeffington’s accepted framework (Liberman 1994). Those well-recognized retinal pathways send output signals in response to changes in the environment. Bart Krekelberg, a brain researcher at Rutgers, postulated a “When is It?” pathway for time judgment in 2003 (Krekelberg 2003)—a concept that has since been documented in the past decade (Kim et al. 2014b).
Current concepts of pharmacotherapy of diabetic macular edema
Published in Expert Opinion on Pharmacotherapy, 2020
Christos Haritoglou, Mathias Maier, Aljoscha S. Neubauer, Albert J. Augustin
In the healthy eye, retinal tissue reveals a very organized structure, and disturbance of its layers, especially in the macular region, may compromise visual function. One such biomarker is the central disorganization of the retinal inner layers (DRIL). The pronounced presence of DRIL at baseline was already correlated with worse baseline function (P < .001) [64]. It was also shown that an increase in DRIL during 4 months of follow up was associated with visual acuity worsening at 8 months (P < .001). The change of DRIL also had an impact visual acuity development: When DRIL increased at least 250 µm at 4 months, no eyes had VA improvement of at least 1 line at 8 months. When DRIL decreased at least 250 µm at 4 months, no eyes revealed a visual acuity decline of at least 1 line at 8 months, with 78% showing a visual acuity improvement of at least 1 line [64].
Every nano-step counts: a critical reflection on do’s and don’ts in researching nanomedicines for retinal gene therapy
Published in Expert Opinion on Drug Delivery, 2023
Karen Peynshaert, Joke Devoldere, Stefaan De Smedt, Katrien Remaut
Overall, retinal gene therapy has seen astounding progress on many levels over the last 20 years. Our insight into the biology of the retina and pathophysiology of retinal diseases has indeed incredibly expanded. Moreover, since the discovery of the first blinding genetic defects in the 1980ʹs more than 280 disease-causing genes have been identified[11]. This is partly attributed to the further development and decreasing costs of next-generation sequencing which stimulated the genetic screening of patients by academic and commercial centers [12,13]. While in the 90ʹs diagnosis was solely based on phenotypical features like retinal fundus imaging and classic visual acuity tests, the advances in genetic testing as of today allow earlier diagnosis and prognosis of inherited retinal diseases, and, importantly, enable phenotype-genotype linking [12–14]. The identification of these genes further led to the discovery of a collection of naturally occurring animal models of retinal disease. In addition, thanks to the progress made in producing targeted mutations and gene knockouts, a wide variety of engineered animal models of diverse species have been added to this collection [14,15]. The increasing insight into inherited retinal disease and its causative mutations together with the growing number of available in vivo disease models provided a solid foundation for the progression of retinal gene therapy.
Malpractice Cases Arising From Telephone Based Telemedicine Triage in Ophthalmology
Published in Seminars in Ophthalmology, 2023
Elias H Kahan, Joshua D Shin, Michael E Jansen, Rebecca Hughes Parker, Ravi Parikh
This analysis showed that most medical malpractice lawsuits related to teleophthalmology resulted from delays in evaluation and/or treatment secondary to telephone visits. Although synchronous live audio-visual evaluation and high-resolution images generated through mobile health applications will become more prominent in the coming years, it is unlikely that telephone communication will ever be completely phased out of ophthalmic practice, and these learnings should be leveraged for mitigating future malpractice across all teleophthalmic encounters. Regarding telephone triage in particular, certain steps can be implemented in current practice to avoid the likelihood of malpractice litigation. Based on our findings, certain symptoms that may portend to endophthalmitis or retinal detachment, such as flashes and floaters, especially in the context of previous vitreous hemorrhage, detachment, or retinal repair, should warrant immediate in-person evaluation.
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