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Relevant bibliographies by topics / Fovea centralis

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Academic literature on the topic 'Fovea centralis'

Author: Grafiati

Published: 4 June 2021

Last updated: 30 July 2024

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Journal articles on the topic "Fovea centralis"

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Salus, Robert. "DAS GEFÄSSSYSTEM DER FOVEA CENTRALIS." Acta Ophthalmologica 17, no. 3 (May 27, 2009): 279–96. http://dx.doi.org/10.1111/j.1755-3768.1939.tb07367.x.

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CAIRNS, JAMES D., and MARK F. McCOMBE. "MICROHOLES OF THE FOVEA CENTRALIS." Australian and New Zealand Journal of Ophthalmology 16, no. 2 (May 1988): 75–79. http://dx.doi.org/10.1111/j.1442-9071.1988.tb01253.x.

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WELLER, CYNTHIA, SARAH H. LINDSTROM, WILLEM J. DE GRIP, and MARTIN WILSON. "The area centralis in the chicken retina contains efferent target amacrine cells." Visual Neuroscience 26, no. 2 (March 2009): 249–54. http://dx.doi.org/10.1017/s0952523808080917.

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AbstractThe retinas of birds receive a substantial efferent, or centrifugal, input from a midbrain nucleus. The function of this input is presently unclear, but previous work in the pigeon has shown that efferent input is excluded from the area centralis, suggesting that the functions of the area centralis and the efferent system are incompatible. Using an antibody specific to rods, we have identified the area centralis in another species, the chicken, and mapped the distribution of the unique amacrine cells that are the postsynaptic partners of efferent fibers. Efferent target amacrine cells are found within the chicken area centralis and their density is continuous across the border of the area centralis. In contrast to the pigeon retina then, we conclude that the chicken area centralis receives efferent input. We suggest that the difference between the two species is attributable to the presence of a fovea within the area centralis of the pigeon and its absence from that of the chicken.

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Bagheri, Saghar, Ines Lains, Rebecca F. Silverman, Ivana Kim, Dean Eliott, Rufino Silva, John Miller, et al. "Percentage of Foveal vs Total Macular Geographic Atrophy as a Predictor of Visual Acuity in Age-Related Macular Degeneration." Journal of VitreoRetinal Diseases 3, no. 5 (August 22, 2019): 278–82. http://dx.doi.org/10.1177/2474126419859454.

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Purpose: This article investigates the relationship between visual acuity (VA), total area of geographic atrophy (GA), and percentage of foveal GA. Methods: A multicenter, retrospective, cross-sectional study was conducted of patients with GA due to age-related macular degeneration. Demographics, VA, fundus autofluorescence (FAF), and spectral-domain optical coherence tomography (SD-OCT) images were collected. Using FAF images aided by SD-OCT, fovea-sparing status, GA pattern, total GA size, and percentage of GA covering the foveal area—within a 1.5-mm-diameter circle centered on the fovea centralis—were assessed. Univariable and multiple linear regression analyses were performed. Results: Fifty-four eyes (mean age, 78.7 ±7.7 years [SD], 60.0% female) were studied. Mean VA was 0.8 ± 0.6 logarithm of the minimum angle of resolution (Snellen equivalent 20/126 ± 20/80), mean total GA 8.8 ± 6.7 mm2, and mean percentage of foveal GA was 71.5 ± 30.9%. Of all assessed eyes, 48.2% (n = 26) presented with multifocal GA, and 18.5% (n = 10) had foveal sparing. Multiple regression analysis revealed that, controlling for age and GA pattern, the percentage of foveal GA presented a statistically significant association with VA (ß = 0.41, P = .004). No significant associations were observed with mean total GA size, while controlling for the same variables (ß = 0.010, P = .440). Conclusions: Percentage of foveal GA was significantly associated with VA impairment, although the same was not verified for total GA area. These findings suggest that percentage of foveal GA may represent a more useful tool for assessing the impact of GA on VA. Further validation is needed in larger cohorts.

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В.М., Филиппов,, Петрачков, Д.В., and Барышев, К.В. "Dosed Fovea-Sparing Internal Limiting Membrane Peeling in Diabetic Macular Edema Treatment (Clinical Observations)." Офтальмология. Восточная Европа, no. 4 (January 20, 2023): 500–509. http://dx.doi.org/10.34883/pi.2022.12.4.020.

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Введение. Потребность в лечении офтальмологических осложнений сахарного диабета остается высокой ввиду неуклонного роста числа пациентов с данной патологией. Формы диабетического макулярного отека (ДМО), ассоциированные с наличием аномалий витреомакулярного интерфейса (АВМИ), требуют дифференцированного подхода к тактике ведения пациентов и технике выполнения витреоретинальных хирургических операций. Цель. Демонстрация возможностей метода дозированного центрсберегающего пилинга внутренней пограничной мембраны сетчатки (ДЦСП ВПМ) в лечении ДМО. Материалы и методы. Представлены два клинических наблюдения – случаи лечения ДМО с АВМИ с применением метода ДЦСП ВПМ. В обоих случаях пациентам проведено комбинированное лечение – факоэмульсификация катаракты с имплантацией интраокулярной линзы в сочетании с витрэктомией с мембранопилингом по методике ДЦСП ВПМ. Период послеоперационного наблюдения составил 12 месяцев. Результаты. В ходе динамического наблюдения в первые 3–6 месяцев после лечения отмечали положительную анатомо-функциональную динамику. К 6-му месяцу в обоих случаях выявлено развитие ДМО, что потребовало применения anti-VEGF-терапии. В случае 1 к 12-му месяцу наблюдения отмечали анатомическое улучшение, но за счет формирования твердого экссудата в области fovea centralis острота зрения оказалась ниже исходной. В случае 2 на фоне лечения отмечали медленную положительную динамику течения ДМО с сохранением зрительной функции на уровне послеоперационной. В обоих случаях не наблюдали интра- и послеоперационных осложнений пилинга ВПМ, таких как формирование ятрогенных разрывов сетчатки, отслойки нейроэпителия, развитие послеоперационного эпимакулярного фиброза. Заключение. ДЦСП ВПМ является примером метода протекции fovea centralis в ходе хирургического лечения. Указанные технологии являются перспективными, однако требуют изучения на репрезентативном клиническом материале. Introduction. The need for the treatment of diabetes mellitus (DM) ophthalmic complications remains high due to the steady increase in the number of patients. Forms of diabetic macular edema (DME) associated with the presence of the vitreomacular interface anomalies (VMIA) require a differentiated approach to the management and vitreoretinal surgery technique. Purpose. To demonstrate the possibilities of method of the dosed fovea-sparing peeling of the retinal internal limiting membrane (DFSP ILM) in the DME treatment. Materials and methods. Two clinical observations are presented – cases of VMIA-DME treatment using the DFSP ILM method. In both cases, the patients underwent combined treatment: cataract phacoemulsification with intraocular lens implantation in combination with vitrectomy (VRS) with DFSP ILM peeling. The postoperative follow-up period was 12 months. Results. During the dynamic observation in the first 3–6 months after treatment, positive anatomical and functional results were noted. By the 6th month, the development of DME was detected in both cases, which required the use of anti-VEGF therapy. In case 1, by the 12th month of observation, anatomical improvement was noted, but due to the formation of hard exudate in the fovea centralis area, visual acuity was lower than the initial one. In case 2, against the background of treatment, a slow positive dynamics of DME was noted with the preservation of visual function at the postoperative level. In both cases, intra- and postoperative complications of DFSP ILM peeling were not observed, such as the formation of iatrogenic retinal tears, detachment of the neuroepithelium, and the development of postoperative epimacular membrane. Conclusion. DFSP ILM is an example of a fovea centralis protection method during VRS. These technologies are promising, however, they require study on representative clinical material.

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WILLIAMS, T. D., and J. M. WILKINSON. "Position of the Fovea Centralis with Respect to the Optic Nerve Head." Optometry and Vision Science 69, no. 5 (May 1992): 369–77. http://dx.doi.org/10.1097/00006324-199205000-00006.

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Cicerone, Carol M., and Janice L. Nerger. "The density of cones in the fovea centralis of the human dichromat." Vision Research 29, no. 11 (January 1989): 1587–95. http://dx.doi.org/10.1016/0042-6989(89)90140-5.

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Mammo, Zaid, Chandrakumar Balaratnasingam, Paula Yu, Jing Xu, Morgan Heisler, Paul Mackenzie, Andrew Merkur, et al. "Quantitative Noninvasive Angiography of the Fovea Centralis Using Speckle Variance Optical Coherence Tomography." Investigative Opthalmology & Visual Science 56, no. 9 (August 3, 2015): 5074. http://dx.doi.org/10.1167/iovs.15-16773.

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Gass, J. Donald M. "Müller Cell Cone, an Overlooked Part of the Anatomy of the Fovea Centralis." Archives of Ophthalmology 117, no. 6 (June 1, 1999): 821. http://dx.doi.org/10.1001/archopht.117.6.821.

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Ueda, Kaori, Takayuki Nagai, Aya Chubachi, Yasuyuki Sotani, Ryuto Nishisho, and Makoto Nakamura. "Comparison of Two Cases of Foveal Laceration Caused by a Mower." Case Reports in Ophthalmology 12, no. 3 (October 14, 2021): 848–53. http://dx.doi.org/10.1159/000518807.

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We report and compare 2 cases of open globe injury with foveal damage incurred while mowing. Case 1 is a healthy 67-year-old man presenting with an intraocular metallic foreign body and eye pain in his right eye after using a mower. The foreign body perforated the cornea’s inferior area and damaged the foveal centralis, leading to central scotoma and decreased visual acuity. 27G pars plana vitrectomy was performed, and the final corrected decimal visual acuity was 0.1, but the visual field was preserved, except for the central scotoma. Case 2 is a healthy 50-year-old man presenting open globe injury with an intraocular metallic foreign body while using a mower. The foreign body damaged the fovea and triggered extensive retinal detachment. One month after surgery, proliferative vitreoretinopathy occurred, requiring additional surgery. The final corrected decimal visual acuity dropped to 0.05, resulting in an extensive visual field defect. Both cases of eye trauma were caused by mower injury, but the visual function outcomes differed with the size of the foreign body and the injury severity at the time of onset. Mower eye trauma is preventable, and efforts to educate users on safety measures are needed.

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Dissertations / Theses on the topic "Fovea centralis"

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Hesse, Rüdiger [Verfasser]. "Psychophysische Untersuchungen zur Rolle der Fovea centralis bei der Bewegungswahrnehmung / Rüdiger Hesse." Mainz : Universitätsbibliothek der Johannes Gutenberg-Universität Mainz, 2005. http://d-nb.info/1225685443/34.

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Venkataraman, Abinaya Priya. "Vision Beyond the Fovea: Evaluation and Stimuli Properties." Doctoral thesis, KTH, Biomedicinsk fysik och röntgenfysik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-191212.

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This research is about evaluating vision in the periphery. Peripheral vision is of fundamental importance in the performance of our everyday activities. The aim of this thesis is to develop methods suitable for the evaluation of peripheral vision and to assess how different visual functions vary across the visual field. The results have application both within the field of visual rehabilitation of people with central visual field loss (CFL)and as well as in myopia research. All methods for assessing peripheral vision were implemented with adaptive psychophysical algorithms based on Bayesian statistics. A routine for time-efficient evaluation of peripheral contrast sensitivity was implemented and verified for measurements out to 30° in the visual field. Peripheral vision was evaluated for different properties of the stimuli: sharpness, motion, orientation, and extent. Optical quality was controlled using adaptive optics and/or corrective spectacles specially adapted for the peripheral viewing angle. We found that many peripheral visual functions improved with optical correction, especially in people with CFL. We also found improvements in peripheral contrast sensitivity for low spatial frequencies when stimuli drifted at 5 to 10 Hz; this applies both for people with normal vision and those with CFL. In the periphery, it is easier to see lines that are oriented parallel with respect to the visual field meridian. We have shown that this directional bias is present for both resolution and detection tasks in the periphery, even when the asymmetric optical errors are minimized. For accurate evaluation of peripheral vision, we therefore recommend using gratings that are oriented oblique to the visual field meridian. The directional bias may have implications in how peripheral image quality affects myopia progression. Another proof that peripheral vision can influence central visual function is the fact that, when the stimulus extent was increased beyond the fovea, the blur in the stimulus was less noticeable.
Denna forskning handlar om att utvärdera synen i periferin. Vår perifera syn är ovärderlig i det dagliga livet. Målsättningen med denna avhandling är dels att utveckla metoder speciellt lämpade för perifer synutvärdering och dels att mäta hur olika synfunktioner varierar över synfältet. Resultaten har tillämpning både inom synrehabilitering för personer med centraltsynfältsbortfall och inom närsynthetsforskning. Adaptiv psykofysisk metodologi baserad på Bayesiansk statistik användes vid all utvärdering av det perifera seendet. Vi implementerade en rutin för tidseffektiv mätning av perifer kontrastkänslighet och verifierade den ut till 30° i synfältet. Den perifera synen utvärderades för olika egenskaper hos objektet: skärpa, rörelse, riktning och utbredning. Skärpan kontrollerades med hjälp av adaptiv optik och/eller glasögonkorrektion speciellt anpassad för den perifera synvinkeln. Vi fann att många periferasynfunktioner förbättras av optisk korrektion, särskilt för personer med centralt synfältsbortfall. Vi hittade även förbättringar i periferkontrastkänslighet för låga ortsfrekvenser när objektet modulerades med hastigheter mellan 5 och 10 Hz, vilket gäller både normalseende och personer med centralt synfältsbortfall. I periferin är det lättare att se linjer som är orienterade parallellt med synfältsmeridianen. Vi har visat att denna riktningsbias gäller både för upplösning och detektion i periferin, även när de asymmetriska optiska felen minimeras. För bästa mätnoggrannhet rekommenderar vi därför att använda randmönster som ligger snett relativt synfältsmeridianen. Denna riktningsbias skulle även kunna påverka hur den perifera bildkvalitén inverkar på utvecklingen av närsynthet. Ytterligare ett bevis för att perifer syn kan påverka den centrala synfunktionen är att, när objektets utbredning ökades, uppfattade personen det som mindre suddigt.

QC 20160826

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Rima, Ghashut. "EVALUATION OF MACULAR ISCHEMIA IN EYES WITH CENTRAL RETINAL VEIN OCCLUSION: An Optical Coherence Tomography Angiography Study." Kyoto University, 2018. http://hdl.handle.net/2433/232114.

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Bruce, A., I. E. Pacey, J. A. Bradbury, A. J. Scally, and B. T. Barrett. "Bilateral changes in foveal structure in individuals with amblyopia." 2013. http://hdl.handle.net/10454/5894.

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PURPOSE: To examine foveal structure in amblyopia using spectral-domain optical coherence tomography (SD-OCT). DESIGN: Prospective, cross-sectional study. PARTICIPANTS AND CONTROLS: Two subject groups were recruited to the study: 85 amblyopes (34 adults, 51 children) and 110 visually normal controls (44 adults, 66 children). METHODS: A detailed eye examination, including an SD-OCT scan, was performed in all participants. A total of 390 eyes of 195 subjects were imaged using a 3-dimensional (3D) macula scan covering a nominal 6 x 6-mm area with a resolution of 256 x 256 (65,536 axial scans). Data from the B-scans bisecting the fovea both horizontally and vertically were fitted with a mathematical model of the fovea to determine a range of foveal parameters. MAIN OUTCOME MEASURES: Foveal thickness, foveal pit depth, and foveal pit slope. RESULTS: Bilateral differences between the eyes of amblyopes compared with visually normal controls were found. The difference between foveal structure in amblyopic participants relative to structure in subjects with normal vision persisted even when variables such as age, ethnicity, axial length, and sex were taken into account. Amblyopes showed increased foveal thickness (+8.31 mum; P = 0.006) and a reduction in pit depth in the horizontal meridian (-10.06 mum; P = 0.005) but not in the vertical meridian (P = 0.082) when compared with subjects with normal vision. Foveal pit slopes were found to be approximately 1 degree flatter in the nasal (P = 0.033) and temporal (P = 0.014) meridians in amblyopes, but differences between amblyopes and controls in the superior (P = 0.061) and inferior (P = 0.087) meridians did not reach statistical significance. No statistically significant interocular differences were found in the foveal structure between amblyopic and fellow eyes. CONCLUSIONS: Differences were found in the foveal structure in both eyes of amblyopes compared with subjects with normal vision. These differences consisted of increased foveal thickness, reduced pit depth when measured along the horizontal meridian, and flattening of the nasal and temporal sides of the foveal pit.

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Book chapters on the topic "Fovea centralis"

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Galan-Hernandez, Juan C., Vicente Alarcon-Aquino, Oleg Starostenko, Juan Manuel Ramirez-Cortes, and Pilar Gomez-Gil. "Advances in Image and Video Compression Using Wavelet Transforms and Fovea Centralis." In Machine Vision and Navigation, 629–55. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-22587-2_19.

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"Fovea Centralis." In Encyclopedia of Clinical Neuropsychology, 1073. New York, NY: Springer New York, 2011. http://dx.doi.org/10.1007/978-0-387-79948-3_4518.

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Banerjee, Anwesha, Ankita Mazumder, Poulami Ghosh, and D. N. Tibarewala. "Visual Perception from Object Scanning as Revealed by Electrooculography." In Advances in Bioinformatics and Biomedical Engineering, 147–63. IGI Global, 2016. http://dx.doi.org/10.4018/978-1-4666-8811-7.ch007.

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We the human beings are blessed by the nature to become well competent for performing highly precise and copious visual processes with how ever a restricted field of view. Howbeit, this process of visual perception is, to a great extent, controlled by the saccades or more commonly the eye movements. The positioning and accommodation of eyes allows an image to be placed (or fixed) in the fovea centralis of the eyes but although we do so to fix our gaze at a particular object, our eyes continuously move. Even though these fixational eye movements includes magnitude that should make them visible to us yet we remain oblivious to them. Microsacades, drifts and tremors that occurs frequently during fixational eye movements, contribute largely to the visual perception. We use saccades several times per second to move the fovea between points of interest and build an understanding of our visual environment.

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Banerjee, Anwesha, Ankita Mazumder, Poulami Ghosh, and D. N. Tibarewala. "Visual Perception from Object Scanning as Revealed by Electrooculography." In Ophthalmology, 98–114. IGI Global, 2018. http://dx.doi.org/10.4018/978-1-5225-5195-9.ch007.

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We the human beings are blessed by the nature to become well competent for performing highly precise and copious visual processes with how ever a restricted field of view. Howbeit, this process of visual perception is, to a great extent, controlled by the saccades or more commonly the eye movements. The positioning and accommodation of eyes allows an image to be placed (or fixed) in the fovea centralis of the eyes but although we do so to fix our gaze at a particular object, our eyes continuously move. Even though these fixational eye movements includes magnitude that should make them visible to us yet we remain oblivious to them. Microsacades, drifts and tremors that occurs frequently during fixational eye movements, contribute largely to the visual perception. We use saccades several times per second to move the fovea between points of interest and build an understanding of our visual environment.

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Loewy, A. D. "Autonomic Control of the Eye." In Central Regulation of Autonomic Functions, 268–85. Oxford University PressNew York, NY, 1990. http://dx.doi.org/10.1093/oso/9780195051063.003.0015.

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Abstract For the eye to function normally, a variety of functions that are under control of the autonomic nervous system need to be maintained. These functions include autonomic adjustments of smooth muscles controlling the iris and the lens so that a focused image is projected onto the fovea, as well as sympathetic regulation of the uveal blood vessels to pro vide nutrients to the ocular tissues. This chapter re views the neural pathways involved in (l) the pupillary light reflex, (2) the accommodation response, (3) the regulation of blood flow to the eye, and (4) the control of intraocular pressure.

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Penman, Alan D., Kimberly W. Crowder, and William M. Watkins. "Grid Pattern Photocoagulation for Macular Edema in Central Vein Occlusion." In 50 Studies Every Ophthalmologist Should Know, 133–38. Oxford University Press, 2020. http://dx.doi.org/10.1093/med/9780190050726.003.0023.

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The Central Vein Occlusion Study (CVOS) was a randomized, controlled, clinical trial to determine whether treatment with macular grid photocoagulation improved or preserved visual acuity in eyes with macular edema involving the fovea secondary to nonischemic central retinal vein occlusion (CRVO) and best corrected visual acuity of 20/50 or worse. The study found that, overall, visual acuity results were not different for treated and control eyes. Based on this, the standard of care at that time continued to be observation. (Treatment with intravitreal anti–vascular endothelial growth factor [VEGF] agents is now the standard of care.)

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Brinton, Daniel A., and Charles P. Wilkinson. "Establishing the Diagnosis." In Retinal Detachment. Oxford University Press, 2009. http://dx.doi.org/10.1093/oso/9780195330823.003.0009.

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The differential diagnosis of rhegmatogenous retinal detachment includes secondary (nonrhegmatogenous) retinal detachment and other entities that may simulate a retinal detachment. Nonrhegmatogenous detachments are categorized as exudative (serous) and tractional detachments. Conditions that may be mistaken for retinal detachment include retinoschisis, choroidal detachment or tumors, and vitreous membranes. Sometimes benign findings in the peripheral retina are mistaken for retinal breaks. The most prominent feature of the fundus is the optic nerve head or disc, the only place in the human body that affords a direct view of a tract of the central nervous system. The foveola, the functional center of the fundus, is located in the center of the fovea, which has a diameter of about 5°. The macula is centered on the fovea and has a diameter of about 17°. The multiple branches of the central retinal artery are readily identifi ed by their bright red color and relatively narrow caliber. The multiple tributaries of the central retinal vein are recognized by their dark red color and relatively wider caliber. In a darkly pigmented fundus, the choroidal vessels in the posterior pole can be obscured from view, but in an eye with minimal pigment, they are readily visible. The venous tributaries of the choroid that make up the vortex veins are usually easily seen. The most prominent features of the choroidal venous system are the vortex ampullae, of which there are usually four (but sometimes more). They are located approximately in the 1-, 5-, 7-, and 11-o’clock meridians, just posterior to the equator. The horizontal meridians are usually identifiable by their radially oriented, long posterior ciliary nerves, and infrequently the long posterior ciliary artery can be seen adjacent to the nerve. The nerve is relatively broad and has a yellow color, and the artery is identifiable by its red color. The artery is usually inferior to the nerve temporally, and superior to it nasally (Figure 5–1).

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Wray, Shirley H. "Oscillopsia, Nystagmus, Saccadic Oscillations, and Intrusions." In Eye Movement Disorders in Clinical Practice, 373–412. Oxford University Press, 2014. http://dx.doi.org/10.1093/med/9780199921805.003.0010.

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Nystagmus, defined as an involuntary repetitive, rhythmic to-and-fro movement of the eyes initiated by a slow drift that shifts an image off the fovea, is discussed in detail. The steps to take in evaluating nystagmus are emphasized , including the importance of close observation with the patient supine, prone, and lying on either side Central vestibular nystagmus due to disease of the central nervous system is covered fully and case studies include patients with upbeat nystagmus and with acquired pendular nystagmus.. When a saccadic eye movement takes the eye away from fixation (saccadic intrusion), a variety of saccadic oscillations can occur, in particular multidirectional saccades without an intersaccadic interval, which is diagnostic of opsoclonus; ocular flutter; or the two oscillations combined. . Two paraneoplastic syndromes illustrate these disorders , a case of ocular flutter associated with paraneoplastic encephalitis and cancer of the lung, and an infant with opsoclonus as the herald syndrome of a neuroblastoma.

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Enns, James T., and Erin Austen. "Mental Schemata And The Limits Of Perception." In In The Mind’s Eye Julian Hochberg, 439–47. Oxford University PressNew York, NY, 1992. http://dx.doi.org/10.1093/oso/9780195176919.003.0024.

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Abstract Julian Hochberg deserves full credit for giving serious consideration to one of the most obvious and yet overlooked limitations of the human visual system. This is the fact that vision is not uniformly detailed over the field of view. Or, as he liked to put it, ‘‘unlike objects themselves, our perception of objects is not everywhere dense’’ (Hochberg, 1982, p. 214). He was referring to the fact that retinal cones are concentrated near the fovea, so as to maximize spatial resolution for only the central 1–28 around the point of fixation. This limitation means that in order to view any scene in detail, a series of eye movements and fixations must be made. It also implies that our subjective experience of a wide-angled field of view that is high in detail is an illusion, as many textbook demonstrations now attest. Yet, despite this knowledge, formal theories of vision, for the most part, paid very little attention to it until rather late into the 20th century. Even David Marr’s (1982) Vision, the book often credited with the greatest influence on vision science in the past quarter century, is remarkably silent on the consequences of this fundamental limitation.

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MD, Miguel A. Quiroz-Reyes, Erick A. Quiroz-Gonzalez, Miguel A. Quiroz-Gonzalez, Ahmad R. Alsaber, Sanjay Marasini, and Virgilio Lima-Gomez. "Postoperative Analysis of Macular Perfusional Status in Giant Retinal Tear-Related Retinal Detachments." In Optical Coherence Tomography Angiography for Choroidal and Vitreoretinal Disorders - Part 1, 177–205. BENTHAM SCIENCE PUBLISHERS, 2023. http://dx.doi.org/10.2174/9789815124095123010012.

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Rhegmatogenous retinal detachment (RRD) associated with giant retinal tears (GRTs) can cause significant visual impairment due to structural or perfusional macular sequelae. This condition is an acute-onset incident that leads to a full-thickness circumferential retinal tear of at least 90°. Limited data are available concerning the patients´ long-term perfusional status after successful surgery for GRTs with macula.off RRD. This chapter examines the long-term outcomes of eyes treated with varying degrees of GRT-associated RRD extensions and compares them with those of two control groups. The surgical group was subdivided according to GRT-associated RRD extension as follows: eyes with extension of <180° and eyes with extension > of >180°. The eyes were further classified according to whether complementary 360° scleral buckle (SB) placement was required. Postoperative optical coherence tomography (OCT) demonstrated that 33.3% of the eyes had abnormal foveal contours, 39.4% had ellipsoid zone (EZ) disruption, 2 had dissociated optic nerve fiber layer (DONFL) defects, and 45.4% had external limiting membrane (ELM) line discontinuities. OCT angiography (OCT-A) revealed abnormal perfusion indices in surgically treated eyes (p<0.0001). Postsurgical best-corrected visual acuity (BCVA) was negatively correlated with the superficial foveal avascular zone area, superficial parafoveal vessel density, and central subfoveal thickness but positively correlated with the choriocapillaris flow area (CFA). Moreover, eyes treated surgically for GRT-associated RRD had multiple structural alterations reflected by spectral-domain OCT biomarkers and OCT-A perfusional findings correlated with visual outcomes. Despite successful retinal reattachment without proliferation, management of GRT-associated RRD remains challenging.

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Conference papers on the topic "Fovea centralis"

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Cicerone, Carol M. "Composition of the cone mosaic in the human retina." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1989. http://dx.doi.org/10.1364/oam.1989.thv2.

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Measurements of the relative numbers of the three cone types in human fovea centralis and parafovea are presented. The relative numbers of long-wavelength sensitive (L) to middle-wavelength sensitive (M) cones were estimated by applying a model which links the detection of a 1-min test to the number of cones contributing to detection in L cone isolating or M cone isolating conditions.1 In fovea centralis, nine observers (1.46, 1.61, 1.99, 2.00, 2.05, 2.07, 2.28, 2.36, and 2.47) yield a mean value near 2 L cones for each M cone. The relative numbers of L and M cones remain constant from fovea centralis to 4° into the parafovea.

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2

Goelz, Stefan, Joerg P. Fischer, Ronald Klitsche, and Josef F. Bille. "Measurement of the Z-transfer function in the fovea centralis of the human eye using a new confocal laser scanning device." In Europto Biomedical Optics '93, edited by Shlomo T. Melamed. SPIE, 1994. http://dx.doi.org/10.1117/12.168721.

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Otake, Shiro, and Carol M. Cicerone. "The Relative Numbers of L and M cones in Peripheral Retina." In Advances in Color Vision. Washington, D.C.: Optica Publishing Group, 1992. http://dx.doi.org/10.1364/acv.1992.fb8.

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The relative number of long-wavelength-sensitive (L) cones and middle-wavelength-sensitive (M) cones has been estimated recently using psychophysical methods (1, 2). Previous experiments in this laboratory have estimated the relative number to be about 2:1 in central fovea (1) and have shown that the relative number corresponds to color appearance in foveal vision (3).

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4

Swanson, William H., Ronald L. Fellman, John R. Lynn, and Richard J. Starita. "Foveal Ganglion Cell Function in Patients with Stabilized Glaucoma and a Clinically Normal Fovea." In Vision Science and its Applications. Washington, D.C.: Optica Publishing Group, 1996. http://dx.doi.org/10.1364/vsia.1996.saa.4.

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Clinical automated static perimetry for glaucoma typically measures white-on-white increment thresholds for a grid of locations throughout the central visual field.1,2 Relative scotomas (regions of the visual field for which threshold is abnormally high) are early signs of glaucomatous damage. Increase in number, size or depth of relative scotomas is an indication of progression of glaucomatous damage. Surgical reduction of intraocular pressure (IOP) to subnormal levels can halt progression of perimetric defect for several years even in cases of extreme damage.3

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5

Schuchard, Ronald A., Shawn Cooper, and Vasudevan Lakshminarayanan. "Time Series Analysis of PRL Movement during Fixation." In Vision Science and its Applications. Washington, D.C.: Optica Publishing Group, 1996. http://dx.doi.org/10.1364/vsia.1996.thb.1.

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Previous studies of eccentric PRLs (preferred retinal loci) due to central scotoma have documented that the PRLs for fixation are significantly larger than foveal PRLs for fixation (e.g., (Schuchard and Raasch, 1992; Fletcher and Schuchard, 1995)). The fixation target can be found within a 9 degree or smaller retinal area for eccentric PRLs while foveal PRLs (i.e., normally functioning foveas) usually keep the fixation target within a 2 degree or smaller retinal area. These previous investigations of PRLs for fixation have studied the two dimensional spatial characteristics of monocular PRLs but not the dynamic temporal/spatial characteristics of the PRL during fixation. Therefore, it is not known whether the increased PRL size is due to larger drifts and/or microsaccades during fixation (although from this point on we will refer to the microsaccades as jerks since these small jumps can be quite large for some subjects).

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Siminoff, Robert. "Image resolution by simulated bipolar cells of the human central fovea." In SC - DL tentative, edited by Bernice E. Rogowitz and Jan P. Allebach. SPIE, 1990. http://dx.doi.org/10.1117/12.19664.

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7

Banks, Martin S., Patrick J. Bennett, and Gregory A. Gubrud. "Phase discrimination in the normal and amblyopic fovea." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1986. http://dx.doi.org/10.1364/oam.1986.tut3.

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Several investigators have observed anomalies in the encoding of spatial phase in amblyopic eyes. We adapted the paradigm of Field and Nachmias1 to examine amblyopic phase encoding in greater detail. Two normal observers and two with anisometropic amblyopia viewed stimuli composed of a fundamental and second harmonic added in various phases. The stimuli were presented foveally. For each eye tested, the spatial frequency of the fundamental was set to the peak of the CSF. The stimuli were Gaussian-damped and presented in a 2IFC discrimination paradigm. When the stimuli were in fact different, they differed only in the polarity of the second harmonic (180° shift). Thresholds were measured by varying the contrast of the second harmonic. Only two mechanisms were required to account for foveal phase discriminations in nonamblyopic eyes. The odd-symmetric mechanisms were slightly less sensitive than the even-symmetric mechanisms. The amblyopic data were also consistent with the two-mechanism model, but the odd-symmetric mechanisms were distinctly less sensitive than the even-symmetric. The difference between odd and even sensitivity was correlated with the depth of the amblyopia. These results suggest that the phase-encoding anomalies observed in the amblyopic central visual field may reflect a diminished sensitivity (or reliability) among odd-symmetric mechanisms. The pattern of results in the amblyopic fovea is similar to that observed in the peripheral visual field of normal obsevers (2). For the two amblyopic eyes, the results were similar to those observed between 20° and 40° eccentric in normal eyes.

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Heron, Gordon, Anthony J. Adams, and Roger Husted. "Central and Peripheral Measures of Blue-Sensitive Pathways in Glaucoma and Ocular Hypertension." In Noninvasive Assessment of the Visual System. Washington, D.C.: Optica Publishing Group, 1986. http://dx.doi.org/10.1364/navs.1986.wc1.

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It is well established that an acquired blue-dyschromatopsia is often present in glaucoma.1 In addition, foveal spectral sensitivity measures in glaucoma have shown that the chromatic pathways are affected (the short wavelength region being particularly depressed).2-5 Combined, these results suggest that the blue sensitive pathways are primarily at risk in glaucoma. A large body of data from color testing, in addition to measures of flicker sensitivity, provides us with considerable evidence that foveal function is abnormal in glaucoma, even when acuity is not affected.6-14 Even greater emphasis has been placed on foveal function in glaucoma since the startling report by Quigley, et al., that as many as half of the optic nerve fibers are destroyed before any abnormality in the visual field is detected.15

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9

Ahumada, Al. "Models for the arrangement of long and medium wavelength cones in the central fovea." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1986. http://dx.doi.org/10.1364/oam.1986.thi1.

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Rules for assigning cones to the two-wavelength sensitivity classes long (L) and medium (M) have been added to the close-packing model for foveolar cone positions. The packing model places each cone tightly against two other cones already in place, so it is natural to consider schemes which assign each cone on the basis of the assignments of the two cones with which it is being placed in contact. The simplest deterministic assignment with reasonable properties is to assign the new cone to the opposite class if the two are the same and to make the assignment L if they are different. This rule generates a proportion of ~62% L and 38% M, not exactly the 2 to 1 rule that has been proposed, but fairly close. The rule has the important feature that it does not depend on the assumption of exact hexagonal (triangular) packing for its implementation. The aliasing properties of retinas generated by this rule and by random assignment with corresponding proportions are demonstrated for chromatic gratings and for luminance gratings in the case that one class is desensitized.

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10

Gu, Y., and Gordon E. Legge. "Accommodation to stimuli in peripheral vision?" In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1985. http://dx.doi.org/10.1364/oam.1985.thh7.

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According to one view, only stimuli presented to the fovea can elicit accommodative responses. However, clinicians report accommodation in patients with central-field loss, suggesting that peripheral vision can play a role. We used a laser optometer to measure accommodation to central and peripheral targets in subjects with normal vision. The targets consisted of featureless black disks superimposed on a uniform white field. Disk radii were 1 °, 7°, 15°, and 30°. Subjects fixated a laser-speckle pattern at the center of the disk. Eye-movement recording confirmed the stability of fixation. Since images of laser speckle patterns remain sharp independent of focus, the circular contour of the black disk on the white background provided the only stimulus to accommodation. For each disk, we measured monocular accommodation as a function of light vergence to estimate the amplitude of accommodation for contours at different retinal eccentricities. Accommodation was observed at all eccentricities, but declined outward from the fovea. Typical amplitudes of 4-5 D were obtained for the 1 ° disk and 1-2 D for the 30° disk. We conclude that peripheral vision is capable of eliciting accommodation. The possibility that peripheral accommodation is mediated by convergence accommodation is discussed.

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