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Journal articles on the topic 'Fovea centralis'

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Published: 4 June 2021
Last updated: 30 July 2024

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1

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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2

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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3

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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4

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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5

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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6

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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7

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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8

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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9

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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10

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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11

Krebs, Ingeborg P., and Wolf Krebs. "Discontinuities of the external limiting membrane in the fovea centralis of the primate retina." Experimental Eye Research 48, no. 2 (February 1989): 295–301. http://dx.doi.org/10.1016/s0014-4835(89)80078-8.

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12

OHSHIMA, Shigemichi, and Kazuhiko KATO. "B22 A study of gaze point pattern analysis in movement prediction considering a fovea centralis structure." Proceedings of Joint Symposium: Symposium on Sports Engineering, Symposium on Human Dynamics 2006 (2006): 290–95. http://dx.doi.org/10.1299/jsmesports.2006.0_290.

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13

Gorges, Martin, Elmar H. Pinkhardt, and Jan Kassubek. "Alterations of Eye Movement Control in Neurodegenerative Movement Disorders." Journal of Ophthalmology 2014 (2014): 1–11. http://dx.doi.org/10.1155/2014/658243.

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The evolution of the fovea centralis, the most central part of the retina and the area of the highest visual accuracy, requires humans to shift their gaze rapidly (saccades) to bring some object of interest within the visual field onto the fovea. In addition, humans are equipped with the ability to rotate the eye ball continuously in a highly predicting manner (smooth pursuit) to hold a moving target steadily upon the retina. The functional deficits in neurodegenerative movement disorders (e.g., Parkinsonian syndromes) involve the basal ganglia that are critical in all aspects of movement control. Moreover, neocortical structures, the cerebellum, and the midbrain may become affected by the pathological process. A broad spectrum of eye movement alterations may result, comprising smooth pursuit disturbance (e.g., interrupting saccades), saccadic dysfunction (e.g., hypometric saccades), and abnormal attempted fixation (e.g., pathological nystagmus and square wave jerks). On clinical grounds, videooculography is a sensitive noninvasivein vivotechnique to classify oculomotion function alterations. Eye movements are a valuable window into the integrity of central nervous system structures and their changes in defined neurodegenerative conditions, that is, the oculomotor nuclei in the brainstem together with their directly activating supranuclear centers and the basal ganglia as well as cortical areas of higher cognitive control of attention.
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14

Mitkova-Hristova, Vesela T., and Marieta I. Konareva-Kostyaneva. "Macular thickness measurements in healthy eyes using spectral optical coherence tomography." Folia Medica 53, no. 4 (December 1, 2011): 28–33. http://dx.doi.org/10.2478/v10153-011-0064-z.

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ABSTRACT AIM: The aim of the present study was to measure macular thickness in healthy eyes and find whether it changes with age. MATERIAL AND METHODS: We examined 163 healthy eyes of 84 healthy volunteers. In order to measure their macular thickness the patients were examined using spectral-domain optical coherent tomography (SD-ОСТ - iVue, Optovue). They were allocated into 6 age groups. RESULTS: The mean central macular thickness (inner circle - fovea centralis) was 248.9 ± 17.9 μm (mean ± SD), and the mean total macular thickness (an area including 9 subfields as defined by ETDRS) was 286.2 ± 13.9 μm (mean ± SD). We found that it correlated negatively with age (r = - 0.18; p = 0.03; Pearson correlation). CONCLUSION: We found a statistically significant decrease of mean macular thickness as age increased.
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15

Tamm, Ernst R., and Elke Lütjen-Drecoll. "Nitrergic Nerve Cells in the Primate Ciliary Muscle Are Only Present in Species with a Fovea centralis." Ophthalmologica 211, no. 3 (1997): 201–4. http://dx.doi.org/10.1159/000310789.

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16

Cicerone, Carol M., and Janice L. Nerger. "The relative numbers of long-wavelength-sensitive to middle-wavelength-sensitive cones in the human fovea centralis." Vision Research 29, no. 1 (January 1989): 115–28. http://dx.doi.org/10.1016/0042-6989(89)90178-8.

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17

Sato, Yoshiki, Kenichi Kimoto, Yasuhiro Takaki, and Toshiaki Kubota. "Macular neovascularisation in a patient with osteogenesis imperfecta exhibiting a novelCOL1A1mutation." BMJ Case Reports 15, no. 11 (November 2022): e251763. http://dx.doi.org/10.1136/bcr-2022-251763.

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Osteogenesis imperfecta is a congenital disease that presents with varying degrees of connective tissue symptoms, including susceptibility to fracture, growth disorders and hearing loss. Here, we discuss a case in which macular neovascularisation (MNV) resulted in metamorphopsia and decreased visual acuity in a patient with osteogenesis imperfecta exhibiting a novelCOL1A1gene mutation (p.Tyr165*). The patient was a woman in her 30s who reported experiencing distorted vision and diminished visual acuity in her right eye for 1 month as well as a history of hearing loss. Rapid improvements in exudative changes and suppression of relapse were achieved after only two intravitreal injections of ranibizumab. Furthermore, since MNV occurred slightly inferior to the fovea centralis, improvements in visual acuity were better than previously reported. As fragility of Bruch’s membrane represents the basis of onset, recurrence and relapse are likely in patients exhibiting MNV, highlighting the need for regular follow-up.
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Zhang, Qinqin, Maureen Neitz, Jay Neitz, and Ruikang K. Wang. "Geographic mapping of choroidal thickness in myopic eyes using 1050-nm spectral domain optical coherence tomography." Journal of Innovative Optical Health Sciences 08, no. 04 (July 2015): 1550012. http://dx.doi.org/10.1142/s1793545815500121.

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Purpose: To provide a geographical map of choroidal thickness (CT) around the macular region among subjects with low, moderate and high myopia. Methods: 20 myopic subjects (n = 40 eyes) without other identified pathologies participated in this study: 20 eyes of ≤ 3 diopters (D) (low myopic), 10 eyes between -3 and -6D (moderate myopic), and 10 eyes of ≥ 6D (high myopic). The mean age of subjects was 30.2 years (± 7.6 years; range, 24 to 46 years). A 1050 nm spectral-domain optical coherence tomography (SD-OCT) system, operating at 120 kHz imaging rate, was used in this study to simultaneously capture 3D anatomical images of the choroid and measure intraocular length (IOL) in the subject. The 3D OCT images of the choroid were segmented into superior, inferior, nasal and temporal quadrants, from which the CT was measured, representing radial distance between the outer retinal pigment epithelium (RPE) layer and inner scleral border. Measurements were made within concentric regions centered at fovea centralis, extended to 5 mm away from fovea at 1 mm intervals in the nasal and temporal directions. The measured IOL was the distance from the anterior cornea surface to the RPE in alignment along the optical axis of the eye. Statistical analysis was performed to evaluate CT at each geographic region and observe the relationship between CT and the degree of myopia. Results: For low myopic eyes, the IOL was measured at 24.619 ± 0.016 mm. The CT (273.85 ± 49.01 μm) was greatest under fovea as is in the case of healthy eyes. Peripheral to the fovea, the mean CT decreased rapidly along the nasal direction, reaching a minimum of 180.65 ± 58.25μm at 5 mm away from the fovea. There was less of a change in thickness from the fovea in the temporal direction reaching a minimum of 234.25 ± 42.27 μm. In contrast to the low myopic eyes, for moderate and high myopic eyes, CTs were thickest in temporal region (where CT = 194.94 ± 27.28 and 163 ± 34.89 μm, respectively). Like the low myopic eyes, moderate and high myopic eyes had thinnest CTs in the nasal region (where CT = 100.84 ± 16.75 and 86.64 ± 42.6μm, respectively). High myopic eyes had the longest mean IOL (25.983 ± 0.021mm), while the IOL of moderate myopia was 25.413 ± 0.022 mm (**p < 0.001). The CT reduction rate was calculated at 31.28 μm/D (diopter) from low to moderate myopia, whilst it is 13.49 μm/D from moderate to high myopia. The similar tendency was found for the IOL reduction rate in our study: 0.265 mm/D from low to moderate myopia, and 0.137 mm/D from moderate to high myopia. Conclusion: The CT decreases and the IOL increases gradually with the increase of myopic condition. The current results support the theory that choroidal abnormality may play an important role in the pathogenesis of myopic degeneration.
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Weschta, Melanie, Julian E. Klaas, Nikolaus Feucht, Chris P. Lohmann, and Mathias Maier. "Microstructural morphology and visual acuity outcome in eyes with epiretinal membrane before, during, and after membrane peeling in intraoperative optical coherence tomography assisted macular surgery." International Journal of Ophthalmology 16, no. 5 (May 18, 2023): 748–54. http://dx.doi.org/10.18240/ijo.2023.05.12.

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AIM: To measure the difference of intraoperative central macular thickness (CMT) before, during, and after membrane peeling and investigate the influence of intraoperative macular stretching on postoperative best corrected visual acuity (BCVA) outcome and postoperative CMT development. METHODS: A total of 59 eyes of 59 patients who underwent vitreoretinal surgery for epiretinal membrane was analyzed. Videos with intraoperative optical coherence tomography (OCT) were recorded. Difference of intraoperative CMT before, during, and after peeling was measured. Pre- and postoperatively obtained BCVA and spectral-domain OCT images were analyzed. RESULTS: Mean age of the patients was 70±8.13y (range 46-86y). Mean baseline BCVA was 0.49±0.27 logMAR (range 0.1-1.3). Three and six months postoperatively the mean BCVA was 0.36±0.25 (P=0.01 vs baseline) and 0.38±0.35 (P=0.08 vs baseline) logMAR respectively. Mean stretch of the macula during surgery was 29% from baseline (range 2%-159%). Intraoperative findings of macular stretching did not correlate with visual acuity outcome within 6mo after surgery (r=-0.06, P=0.72). However, extent of macular stretching during surgery significantly correlated with less reduction of CMT at the fovea centralis (r=-0.43, P<0.01) and 1 mm nasal and temporal from the fovea (r=-0.37, P=0.02 and r=-0.50, P<0.01 respectively) 3mo postoperatively. CONCLUSION: The extent of retinal stretching during membrane peeling may predict the development of postoperative central retinal thickness, though there is no correlation with visual acuity development within the first 6mo postoperatively.
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20

Shafa, Tooba, Mohsin Jamil, and Syed Omer Gilani. "A Review on Structural Analysis of Human Retinal Vessels: Blood Vessels, Optic Nerve, Fovea Centralis and Related Diseases." International Journal of u- and e- Service, Science and Technology 10, no. 12 (December 31, 2017): 1–12. http://dx.doi.org/10.14257/ijunesst.2017.10.12.01.

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21

Rostgaard, Jørgen, and Klaus Qvortrup. "A note about retinal structure and visual acuity. A light microscopic study of the cones in fovea centralis." Acta Ophthalmologica Scandinavica 77, no. 1 (February 1999): 45–49. http://dx.doi.org/10.1034/j.1600-0420.1999.770111.x.

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22

Maloca, Peter M., Philippe Valmaggia, Theresa Hartmann, Marlene Juedes, Pascal W. Hasler, Hendrik P. N. Scholl, and Nora Denk. "Volumetric subfield analysis of cynomolgus monkey’s choroid derived from hybrid machine learning optical coherence tomography segmentation." PLOS ONE 17, no. 9 (September 23, 2022): e0275050. http://dx.doi.org/10.1371/journal.pone.0275050.

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This study aimed to provide volumetric choroidal readings regarding sex, origin, and eye side from healthy cynomolgus monkey eyes as a reference database using optical coherence tomography (OCT) imaging. A machine learning (ML) algorithm was used to extract the choroid from the volumetric OCT data. Classical computer vision methods were then applied to automatically identify the deepest location in the foveolar depression. The choroidal thickness was determined from this reference point. A total of 374 eyes of 203 cynomolgus macaques from Asian and Mauritius origin were included in the analysis. The overall subfoveolar mean choroidal volume in zone 1, in the region of the central bouquet, was 0.156 mm3 (range, 0.131–0.193 mm3). For the central choroid volume, the coefficient of variation (CV) was found of 6.3%, indicating relatively little variation. Our results show, based on analyses of variance, that monkey origin (Asian or Mauritius) does not influence choroid volumes. Sex had a significant influence on choroidal volumes in the superior-inferior axis (p ≤ 0.01), but not in the fovea centralis. A homogeneous foveolar choroidal architecture was also observed.
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Sato, Takaki, Ryohsuke Kohmoto, Masanori Fukumoto, Seita Morishita, Daisaku Kimura, Kensuke Tajiri, Takatoshi Kobayashi, Teruyo Kida, Shota Kojima, and Tsunehiko Ikeda. "A Case of Diabetic Macular Edema with Prominent Chorioretinal Folds." Case Reports in Ophthalmology 8, no. 1 (March 7, 2017): 163–69. http://dx.doi.org/10.1159/000461574.

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Purpose: To report a case of diabetic macular edema with prominent chorioretinal folds. Case Report: This study involved a 55-year-old male with untreated bilateral diabetic retinopathy who had undergone cataract surgery at another clinic. Following that surgery, diabetic macular edema rapidly exacerbated, accentuating marked cystoid macular edema and radial chorioretinal folds in the macula. Investigation of his medical history revealed that in addition to diabetes, he had uncontrolled hypertension and severe diabetic nephropathy. Vitreous surgery was performed on both eyes due to a resistance to a subtenon injection of triamcinolone acetonide or intravitreal injection of an antivascular endothelial growth factor agent. After surgery, the macular edema and chorioretinal folds showed a tendency towards improvement. Thereafter, kidney transplant surgery was performed for renal failure, and a mild tendency of chorioretinal folds was observed. Conclusion: In the case presented in this study, we observed remarkable cystoid macular edema in the fovea centralis and theorize that distortion with the surrounding tissue might have occurred, thus leading to the formation of chorioretinal folds around the macula.
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Nair, Archana A., Rebecca Liebenthal, Shefali Sood, Grant L. Hom, Marc E. Ohlhausen, Thais F. Conti, Carolina C. S. Valentim, et al. "Determining the Location of the Fovea Centralis Via En-Face SLO and Cross-Sectional OCT Imaging in Patients Without Retinal Pathology." Translational Vision Science & Technology 10, no. 2 (February 17, 2021): 25. http://dx.doi.org/10.1167/tvst.10.2.25.

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25

Matsubara, Hisashi, Ryohei Miyata, Maki Kobayashi, Hideyuki Tsukitome, Kengo Ikesugi, and Mineo Kondo. "Fallbericht über anhaltende Erhöhung des Augeninnendrucks nach multiplen intravitrealen Injektionen mit Ranibizumab und Aflibercept zur Behandlung der neovaskulären altersbedingten Makuladegeneration." Kompass Ophthalmologie 2, no. 2 (2016): 92–95. http://dx.doi.org/10.1159/000448499.

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Intravitreale Injektionen mit Wirkstoffen gegen den vaskulären endothelialen Wachstumsfaktor (VEGF) sind eine gängige Behandlungsmaßnahme bei neovaskulärer altersbedingter Makuladegeneration (nAMD). Obwohl diese Behandlungen sehr effektiv sind, sind in jüngster Zeit multiple Injektionen empfohlen worden, um auch langfristig für eine günstige Prognose zu sorgen. Es liegen jedoch Berichte über einen Anstieg des Augeninnendrucks (AID) nach multiplen Injektionen mit Anti-VEGF-Wirkstoffen vor. Wir präsentieren hier einen Fall von unkontrollierter persistierender AID-Erhöhung nach der Umstellung von intravitrealen Ranibizumab- auf Aflibercept-Injektionen. Bei einem 74-jährigen japanischen Mann ohne Glaukom in der Vorgeschichte, der zur Behandlung einer nAMD 22 Ranibizumab-Injektionen erhalten hatte, stieg nach der 22. Injektion der AID unvermittelt an. Die daraufhin eingeleitete medikamentöse Therapie führte zwar zur Normalisierung des AID, doch unterhalb der Fovea centralis lag auch nach der 25. Ranibizumab-Injektion noch subretinale Flüssigkeit vor. Daher erfolgte eine Umstellung der Therapie von Ranibizumab auf 2-monatliche intravitreale Injektionen mit Aflibercept, begleitet von Glaukom-Medikamenten. Der AID kehrte daraufhin in den Normalbereich zurück. Nach der 11. Aflibercept-Injektion kam es trotz der weiterhin angewandten Glaukom-Medikamente wiederum zu einem plötzlichen AID-Anstieg. Aufgrund dieser anhaltenden AID-Erhöhung wurden die Aflibercept-Injektionen für 16 Wochen ausgesetzt. Da es auch mit einem umfassenden Glaukom-Medikationsschema nicht gelang, den AID zu normalisieren, unterzog sich der Patient einer Trabekulotomie, die zur Rückkehr des AID in den Normalbereich führte. Wir gelangen zu der Schlussfolgerung, dass Patienten, die serielle intravitreale Injektionen eines Anti-VEGF-Wirkstoffs erhalten, aufmerksam überwacht werden müssen, da sich eine schwere und anhaltende okuläre Hypertension entwickeln kann.
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26

Stahl, John S., and Zachary C. Thumser. "Dynamics of abducens nucleus neurons in the awake mouse." Journal of Neurophysiology 108, no. 9 (November 1, 2012): 2509–23. http://dx.doi.org/10.1152/jn.00249.2012.

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The mechanics of the eyeball and orbital tissues (the “ocular motor plant”) are a fundamental determinant of ocular motor signal processing. The mouse is used increasingly in ocular motor physiology, but little is known about its plant mechanics. One way to characterize the mechanics is to determine relationships between extraocular motoneuron firing and eye movement. We recorded abducens nucleus neurons in mice executing compensatory eye movements during 0.1- to 1.6-Hz oscillation in the light. We analyzed firing rates to extract eye position and eye velocity sensitivities, from which we determined time constants of a viscoelastic model of the plant. The majority of abducens neurons were already active with the eye in its central rest position, with only 6% recruited at more abducted positions. Firing rates exhibited largely linear relationships to eye movement, although there was a nonlinearity consisting of increasing modulation in proportion to eye movement as eye amplitudes became small (due to reduced stimulus amplitude or reduced alertness). Eye position and velocity sensitivities changed with stimulus frequency as expected for an ocular motor plant dominated by cascaded viscoelasticities. Transfer function poles lay at approximately 0.1 and 0.9 s. Compared with previously studied animal species, the mouse plant is stiffer than the rabbit but laxer than cat and rhesus. Differences between mouse and rabbit can be explained by scaling for eye size (allometry). Differences between the mouse and cat or rhesus can be explained by differing ocular motor repertoires of animals with and without a fovea or area centralis.
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27

Akhmetshin, R. F., E. A. Abdulaeva, and S. N. Bulgar. "Solar maculopathy. Results of five years of follow-up." Kazan medical journal 94, no. 6 (December 15, 2013): 901–3. http://dx.doi.org/10.17816/kmj1815.

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Aim. To investigate the clinical features of solar maculopathy in a long run by optical coherence tomography. Methods. 31 patients (40 eyes) complaining on scotoma appeared after sun gazing without protection were referred to an advisory clinic of Republican Clinical Hospital of Ophtalmology, Kazan. The mean age of patients was 25.2 years, mean visual acuity - 0.72. In addition to the standard examinations, all patients underwent optical coherence tomography. The patients were followed up for up to 5 years. The examinations were performed before the treatment initiation and repeated on the 15th, 30th and 90th day after the treatment completion. 7 patients (8 eyes) were followed up for 5 years. Results. According to the results of optical coherence tomography, focal retinal edema was found in 9 patients (18 eyes) at the first week. Patients received antioedematic drugs and antioxidants. According to the results of optical coherence tomography a lamellar defect has been formed in fovea centralis on 15th day of treatment. Mean visual acuity improved to 0.78. On 30th and 90th days of treatment, lamellar defect persisted, visual acuity remained unchanged. After 5 years, 7 patients (8 eyes) were re-examined. The mean visual acuity was 0.78, the lamellar defect was still observed by optical coherence tomography. No macular degenerative and dystrophic changes were observed in followed up patients. Conclusion. Sunlight causes permanent damage of the retina. In the first week after the sunburn, marked focal retinal edema in the foveolar area was observed on the tomography, with further formation of a lamellar defect that was not accompanied by degenerative changes in the long-term period. Optical coherence tomography is an informative method of diagnosing solar maculopathy.
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28

SPRINGER, A. D., and A. E. HENDRICKSON. "Development of the primate area of high acuity. 1. Use of finite element analysis models to identify mechanical variables affecting pit formation." Visual Neuroscience 21, no. 1 (January 2004): 53–62. http://dx.doi.org/10.1017/s0952523804041057.

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Most primate retinas have an area dedicated for high visual acuity called the fovea centralis. Little is known about specific mechanisms that drive development of this complex central retinal specialization. The primate area of high acuity (AHA) is characterized by the presence of a pit that displaces the inner retinal layers. Virtual engineering models were analyzed with finite element analysis (FEA) to identify mechanical mechanisms potentially critical for pit formation. Our hypothesis is that the pit emerges within the AHA because it contains an avascular zone (AZ). The absence of blood vessels makes the tissue within the AZ more elastic and malleable than the surrounding vascularized retina. Models evaluated the contribution to pit formation of varying elasticity ratios between the AZ and surrounding retina, AZ shape, and width. The separate and interactive effects of two mechanical variables, intraocular pressure (IOP) and ocular growth-induced retinal stretch, on pit formation were also evaluated. Either stretch or IOP alone produced a pit when applied to a FEA model having a highly elastic AZ surrounded by a less elastic region. Pit depth and width increased when the elasticity ratio increased, but a pit could not be generated in models lacking differential elasticity. IOP alone produced a deeper pit than did stretch alone and the deepest pit resulted from the combined effects of IOP and stretch. These models predict that the pit in the AHA is formed because an absence of vasculature makes the inner retinal tissue of the AZ very deformable. Once a differential elasticity gradient is established, pit formation can be driven by either IOP or ocular growth-induced retinal stretch.
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29

Végh, András, Dániel Péter Magda, Ferenc Kilin, Anita Csorba, Mikós Resch, Zoltán Zsolt Nagy, and Arnold Szabó. "Sejtszintű képalkotás a retina in vivo vizsgálatában: jelen és jövő." Orvosi Hetilap 162, no. 22 (May 30, 2021): 851–60. http://dx.doi.org/10.1556/650.2021.32101.

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Összefoglaló. A látószerv különböző betegségei, valamint egyes szisztémás megbetegedések részben vagy kifejezetten az ideghártya károsodásával járnak. A patológia segítségével ma már tudjuk, hogy ezek a betegségek a retina mely rétegének vagy rétegeinek elváltozásait okozzák: míg az időskori maculadegeneratio a külső retinában található fotoreceptorokat érinti kifejezetten a fovea centralis területén, addig a glaucoma a belső retina ganglionsejtjeinek pusztulásával, valamint e sejtek opticusrostjainak károsodásával jár a stratum ganglionaréban és a stratum neurofibrarumban. Az emberi retina sejtjei azonban egyelőre nem maradéktalanul karakterizáltak, az egyes sejttípusok számát csak becsülni tudjuk, így nem írhatók le az egyes sejtszintű elváltozások sem kellő pontossággal. A szövettani feldolgozás és vizsgálat megfelelő részletességgel tájékoztat a diagnózisról és az elváltozás súlyosságáról, értelemszerűen azonban ez a módszer in vivo nem használható a mindennapi klinikai gyakorlatban. A sejtszintű elváltozások ismerete az egyes kórképekben felvetette és szükségessé tette olyan in vivo, a klinikumban is alkalmazható vizsgálómódszerek kifejlesztését, amelyek lehetőséget nyújtanak a retina neurális és egyéb sejtjeinek celluláris és szubcelluláris szintű vizsgálatára, ideértve a vér alakos elemeit is, amelyek egészséges vagy neovascularis eredetű erekben áramlanak. A jelenleg is használt klinikai vizsgálatok mellett ezek a képalkotó módszerek segítségül szolgálhatnak a diagnózis megerősítésében vagy elvetésében, emellett az elváltozás súlyosságának megítélésében, valamint a progresszió vagy remisszió monitorozásában. Orv Hetil. 2021; 162(22): 851–860. Summary. Diseases of the visual system as well as many systemic illnesses are usually associated with retinal damage. With the help of pathology, we can clearly identify the affected layer(s): while age-related macular degeneration mostly damages the photoreceptors in the outer retina at the central fovea, glaucoma promotes ganglion cell death in the ganglion cell layer and damages respective neural fibers. However, the diverse cell types of the human retina have not been fully characterized yet, thus in most cases our knowledge on cellular pathologies is not precise enough. While histopathological preparation and examination of the retinal tissue provide more detailed information about the diagnosis and the severity of the condition, unfortunately, it cannot be used in vivo in everyday clinical practice. Our understanding of the cellular changes in different diseases has revealed a need for new everyday clinical examination methods that can be used in vivo to asses cellular and subcellular changes in neural and other cells of the retina, such as blood cells flowing in healthy vessels or in vessels of neovascular origin. In addition to the currently used clinical examination methods, these imaging methods could help confirm or dismiss diagnoses, assess the severity of a condition, and monitor disease progression or remission. Orv Hetil. 2021; 162(22): 851–860.
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30

Bayborodov, Y. V., K. S. Zhogolev, L. I. Balashevich, I. E. Panova, and D. R. Mirsaitova. "A Retrospective Analysis of the Results of Microinvasive Posterior Vitrectomy in the Surgical Treatment of Non-Full Thickness Macular Holes." Ophthalmology in Russia 15, no. 2S (July 28, 2018): 239–45. http://dx.doi.org/10.18008/1816-5095-2018-2s-239-245.

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Purpose:to study the effectiveness of the posterior microinvasive vitrectomy in the surgical treatment of non-full thickness macular holes on the basis of the retrospective analysis of the retina changes, identified by OCT, and functional outcomes of surgical treatment.Patients and Methods. A retrospective analysis of outcomes of posterior microinvasive vitrectomy was performed in 30 patients operated about non-full thickness macular holes. The following features were assessed: maximum diameter of the non-full thickness macular holes, the diameter at the base of the hole, the minimum thickness of the retina before and after operation, the maximum thickness of the retina before and after surgery. In addition, the configuration of the hole edges before surgery, the presence of intraretinal cysts before and after surgery, the integrity of the ellipsoid zone of the photoreceptors before and after the operation and the restoration of fovea centralis as a result of surgical treatment were assessed.Results. As a result of surgical treatment the closure of non-full thickness macular holes was reached in all cases. The most corrected visual acuity in the postoperative period was ranged from 0.1 to 1.0 (0,66 ± 0,04). The visual acuity improved in 20 cases (64.5%), remained at the same level in 8 cases (25.8%) and decreased in 3 cases (9.6%, in 1 case due to the development of cataracts). The results of correlation analysis has allowed to establish correlation between the initial BCVA and the maximum retinal thickness (R = –0.4), and residual retinal thickness in the area of the hole (R = –0.3). The increase in visual acuity after surgical treatment significantly affected the recovery of the ellipsoid zone of the photoreceptors (RD = 0.833), regression of the retinal thickness (R = 0.42). In addition, the initial diameter of non-full thickness macular holes, both external and at the base, also had an impact on the increase in BCVA (R = –0.3 and R = –0.25, respectively).Conclusion. Posterior microinvasive vitrectomy in the surgical treatment of non-full thickness macular holes is a highly effective method of treatment, as evidenced by the closure of the defect and improvement or stabilization of the most corrected visual acuity 90.4% cases. On the basis of the retrospective analysis it is found that the most significant increase in the most corrected visual acuity was increased in patients with low visual acuity. The recovery of the ellipsoid zone of photoreceptors, regression of the retinal thickness and the diameter of non-full thickness macular holes, both external and at the base mostly influences nn the recovery of the most corrected visual acuity.
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31

Duysens, J., G. A. Orban, J. Cremieux, and H. Maes. "Velocity selectivity in the cat visual system. III. Contribution of temporal factors." Journal of Neurophysiology 54, no. 4 (October 1, 1985): 1068–83. http://dx.doi.org/10.1152/jn.1985.54.4.1068.

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In 149 units from area 17 and 48 units from area 18 the responses to stationary stimulation of different durations were compared with the responses to the same stimulus (a 0.3 degrees-wide light or dark bar) moving at different velocities. The aim was to test the hypothesis that the range of effective velocities depends on the time needed for the bar to cross the receptive field. Forty-two percent of the area 17 cells and 8% of the area 18 cells responded poorly or not at all to briefly presented stationary stimulation. These cells were unable to respond at high velocities, and for these "duration-sensitive" cells the velocity characteristics are well predicted on the basis of responses to stationary stimulation of different durations. Cells that responded equally well to periods of stationary stimulation ranging from 12.5 to 3,200 ms ("duration-insensitive cells") were found to be able to respond at all equivalent velocities, but their preference for either high, low, or intermediate velocities was not reflected in differences in responsiveness to the different durations tested. Duration-sensitive cells in area 17 tended to have a receptive field near the area centralis, and 73% of them were classified as S-family cells, one third being end-stopped S-cells. In contrast only 18% of the duration-insensitive cells were of the S family, and these S-family cells were rarely end-stopped (1/12) or rarely had receptive fields within 5 degrees of the fovea (3/12). Duration-sensitive cells had very long latencies (median 285 ms) in response to a stationary flashed light bar of 1 s duration but much shorter latencies (median 91 ms) when tested with a slowly moving light bar. This difference was not seen in duration-insensitive cells (median latencies = 61 and 59 ms). The ability to respond at high velocity was contrast dependent. At a low contrast level all cells failed to respond to brief stimulation, whether moving or stationary. At high contrast levels only the duration-insensitive cells showed an increased responsivity to brief stimuli. The absence of responses in duration-sensitive cells to brief stimuli of high contrast may depend upon suppressive influences reaching these cells before the excitatory influences. We conclude that the velocity upper cutoff of most S-family cells with a central receptive field can be predicted from a knowledge of the minimum duration of stationary presentation required for their activation (median ON duration threshold, 200 ms).(ABSTRACT TRUNCATED AT 400 WORDS)
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32

Saklakova, О. A., M. V. Maksimenya, E. V. Fefelova, P. P. Tereshkov, and T. M. Karavaeva. "Changes in the level of some tryptophan metabolites in the blood of patients with type 2 diabetes mellitus complicated by diabetic retinopathy." Siberian Journal of Clinical and Experimental Medicine 39, no. 1 (April 5, 2024): 135–39. http://dx.doi.org/10.29001/2073-8552-2024-39-1-135-139.

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Aim: To study the content of tryptophan and the intermediate metabolites of kynurenine and serotonin pathways of its metabolism in the blood plasma of patients with type 2 diabetes mellitus (DM) and non-proliferative diabetic retinopathy as candidates for markers of the early stage of the pathological process.Material and Methods. Three groups of people were analyzed: the first group of 10 patients with type 2 diabetes mellitus and without diabetic retinopathy; the second group of 10 people with type 2 diabetes mellitus and non-proliferative stage of diabetic retinopathy; and the control group of 10 healthy people. The features of the first group were a decrease of macula’s photosensitivity in the fundus and a slight increase in the central thickness of the retina. Patients with diabetic retinopathy tended to have a moderate number of microaneurysms and microhemorrhages, moderately presented intraretinal microvascular anomalies in one quadrant, vein dilatation, clearness of the central retinal vein and its branches. In the macular zone there was an edema with hard exudates in the center and lateral to the fovea centralis. All participants of the study gave blood on an empty stomach in the morning, and after that in we measured the content of tryptophan (TRP), kynurenins ((kynurenine (KYN), 3-hydroxykynurenine (3-HKYN), kynurenic acid (KYNA)) and the level of L-5-hydroxytyrptophan (5HTrp) in blood plasma by HPLC method with fluorimetric and spectrophotometric detection.Results. The groups of people with type 2 diabetes mellitus showed the increasing of TRP level in blood relatively to healthy individuals: by 15.1% (p = 0.032) and 17.9% (p = 0.030) in the first and second groups, respectively. As for the patients of the first group, the content of their KYN was increased by 57.7% (p = 0.012) and KYNA by 33.6% (p = 0.012) relatively to the control and the concentration of 3-НKYN decreased by 18.1% (p = 0.020) relatively to healthy people. As for the patients in the second group, the changes in their level of kynurenines had the same direction, but were more visible. Thus, the concentration of KYN exceeded the same parameters of healthy individuals by 84.5% (p = 0.001) and the parameters of the first group by 18.0% (p = 0.049); the KYNA level increased by 56.6% (p = 0.001) relatively to the control and by 17.3% (p = 0.049) from that of the first group. There was a decrease in the content of 3-HKYN amounted to 18.6% of the control (p = 0.038) and an increase in the concentration of 5HTrp – 193,9% (p < 0.001).
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Longo, Antonio, Martial Geiser, and Charles E. Riva. "Effet de la lumière sur le flux sanguin de la choroïde dans la région de la fovea centralis1." Klinische Monatsblätter für Augenheilkunde 216, no. 05(216) (May 2000): 311–12. http://dx.doi.org/10.1055/s-2000-10991.

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34

García-Pereyra, Jesús, Ciro G. S. Valdés-Lozano, Emilio Olivares-Sáenz, Omar Alvarado-Gómez, Hiram Medrano-Roldan, and Gabriel Alejandre-Iturbide. "EVALUACIÓN DE GENOTIPOS DE AMARANTO PARA ADAPTABILIDAD PRODUCTIVA EN EL NORESTE DE MÉXICO." Revista Fitotecnia Mexicana 27, Especial_1 (July 27, 2022): 53. http://dx.doi.org/10.35196/rfm.2004.especial_1.53.

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Para definir su capacidad de producción de grano e introducir al amaranto (Amaranthus spp.) como cultivo para el ciclo agrícola de Otoño–Invierno (OI) en el noreste de México, en el Campo Experimental de la Facultad de Agronomía de la Universidad Autónoma de Nuevo León, Marín N. L., México, se condujo un experimento bajo un diseño de bloques completos al azar con arreglo en parcelas divididas y dos repeticiones. Se probaron cuatro genotipos de Amaranthus hypochondriacus L. (655, 153-5-3, 653 y Criollo Tlaxcala) y uno de A. cruentus (33) ubicados en parcelas grandes y cuatro densidades de plantas (31 250, 41 666, 62 500 y 125 000 plantas/ha) en las subparcelas. Se analizó el rendimiento de grano (RG), rendimiento de forraje verde (FOVER), altura de planta (AP) y longitud de panícula (LP). Para RG, en todas las densidades de población el genotipo 33 de A. cruentus superó a los genotipos de A. hypochondriacus, y a 125 000 plantas/ha el genotipo 33 expresó el RG más alto (1 637.5 kg ha-1); para los genotipos de A. hypochondriacus el RG más alto lo presentó el genotipo 655 (306 kg ha-1). La fuerte diferencia en adaptabilidad entre los genotipos de estas dos especies de amaranto a las condiciones ambientales del noreste de México, se explica porque en este ciclo agrícola la floración del amaranto coincidió con días largos y temperaturas superiores a 40 0C, las cuales fueron toleradas por el genotipo 33 de A. cruentus, pues esta especie está adaptada a altitudes de 400 a 1 500 m y climas cálidos del centro y sur de México, no así los genotipos de A. hypochondriacus que se siembran en altitudes de 1 500 a 2 200 m en los Valles Altos Centrales del país, donde la floración ocurre cuando las temperaturas máximas son menores a 27 0C. El genotipo 33 superó a los demás en FOVER y LP; y para AP los genotipos 33 653 y 153-5-3 fueron superiores a los demás. Preliminarmente se estableció que el genotipo 33 de A. cruentus sembrado a 125 000 plantas/ha puede utilizarse para la producción de grano y forraje en el ciclo otoño-invierno en el noreste de México, no así los genotipos de A. hypochondriacus, que son muy sensibles a días largos y a altas temperaturas en floración.
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35

Shalev, Gil, Sebastian W. Schmitt, Heidemarie Embrechts, Gerald Brönstrup, and Silke Christiansen. "Enhanced photovoltaics inspired by the fovea centralis." Scientific Reports 5, no. 1 (February 24, 2015). http://dx.doi.org/10.1038/srep08570.

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36

Fishman, Elizabeth S., Mikaela Louie, Adam M. Miltner, Simranjeet K. Cheema, Joanna Wong, Nicholas M. Schlaeger, Ala Moshiri, Sergi Simó, Alice F. Tarantal, and Anna La Torre. "MicroRNA Signatures of the Developing Primate Fovea." Frontiers in Cell and Developmental Biology 9 (April 8, 2021). http://dx.doi.org/10.3389/fcell.2021.654385.

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Rod and cone photoreceptors differ in their shape, photopigment expression, synaptic connection patterns, light sensitivity, and distribution across the retina. Although rods greatly outnumber cones, human vision is mostly dependent on cone photoreceptors since cones are essential for our sharp visual acuity and color discrimination. In humans and other primates, the fovea centralis (fovea), a specialized region of the central retina, contains the highest density of cones. Despite the vast importance of the fovea for human vision, the molecular mechanisms guiding the development of this region are largely unknown. MicroRNAs (miRNAs) are small post-transcriptional regulators known to orchestrate developmental transitions and cell fate specification in the retina. Here, we have characterized the transcriptional landscape of the developing rhesus monkey retina. Our data indicates that non-human primate fovea development is significantly accelerated compared to the equivalent retinal region at the other side of the optic nerve head, as described previously. Notably, we also identify several miRNAs differentially expressed in the presumptive fovea, including miR-15b-5p, miR-342-5p, miR-30b-5p, miR-103-3p, miR-93-5p as well as the miRNA cluster miR-183/-96/-182. Interestingly, miR-342-5p is enriched in the nasal primate retina and in the peripheral developing mouse retina, while miR-15b is enriched in the temporal primate retina and increases over time in the mouse retina in a central-to-periphery gradient. Together our data constitutes the first characterization of the developing rhesus monkey retinal miRNome and provides novel datasets to attain a more comprehensive understanding of foveal development.
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37

Coppolino, Giuseppe, Adriano Carnevali, Valentina Gatti, Caterina Battaglia, Giorgio Randazzo, Irma Figlia, Gemma Patella, et al. "OCT angiography metrics predict intradialytic hypotension episodes in chronic hemodialysis patients: a pilot, prospective study." Scientific Reports 11, no. 1 (March 30, 2021). http://dx.doi.org/10.1038/s41598-021-86609-0.

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AbstractIn chronic hemodialysis (HD) patients, intradialytic hypotension (IDH) is a complication that increases mortality risk. We run a pilot study to analyzing possible relationships between optical coherence tomography angiography (OCT-A) metrics and IDH with the aim of evaluating if OCT-A could represent a useful tool to stratify the hypotensive risk in dialysis patients. A total of 35 eyes (35 patients) were analyzed. OCT-A was performed before and after a single dialysis session. We performed OCT-A 3 × 3 mm and 6 × 6 mm scanning area focused on the fovea centralis. Patients were then followed up to 30 days (10 HD sessions) and a total of 73 IDHs were recorded, with 12 patients (60%) experiencing at least one IDH. Different OCT-A parameters were reduced after dialysis: central choroid thickness (CCT), 6 × 6 mm foveal whole vessel density (VD) of superficial capillary plexus (SPC) and 6 × 6 mm foveal VD of deep capillary plexus (DCP). At logistic regression analysis, IDH was positively associated with baseline foveal VD of SCP and DCP, while an inverse association was found with the choroid. In Kaplan–Meier analyses of patients categorized according to the ROC-derived optimal thresholds, CCT, the 3 × 3 foveal VD of SCP, the 3 × 3 mm and 6 × 6 mm foveal VD of DCP and the 6 × 6 mm foveal VD of SCP were strongly associated with a higher risk of IDH over the 30-days follow-up. In HD patients, a single OCT-A measurement may represent a non-invasive, rapid tool to evaluate the compliance of vascular bed to HD stress and to stratify the risk of IDH in the short term.
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Demirci, G., S. Karaman Erdur, C. Tanriverdi, F. Dikkaya, and F. Senturk. "Williams-Beuren Syndrome Case with Atypical Flattening of Fovea Centralis, Decreased ILM-RPE Thickness and Irregular Corneal Surface." International Journal of Ophthalmology and Clinical Research 9, no. 1 (March 31, 2022). http://dx.doi.org/10.23937/2378-346x/1410135.

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39

Reifeltshammer, E., N. Feucht, C. P. Lohmann, and M. Maier. "Effekt der „low-dose PDT“ auf die choriokapilläre Perfusion bei cCRCS." Der Ophthalmologe, December 22, 2021. http://dx.doi.org/10.1007/s00347-021-01552-9.

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Zusammenfassung Hintergrund Bei Patienten mit chronischer Chorioretinopathia centralis serosa (cCRCS) soll die „low-dose photodynamische Therapie“ (PDT) über eine kurzfristige choriokapilläre Minderperfusion zu einem langfristigen vaskulären Umbau mit konsekutiver Reduktion der vaskulären Hyperpermeabilität und Leckage führen. Ob sich die verminderte Perfusion gänzlich normalisiert, bleibt jedoch ungeklärt. Hauptziel der retrospektiv angelegten Studie war es, das choriokapilläre Flusssignal nach „low-dose PDT“ mittels optischer Kohärenztomographie-Angiographie (OCT‑A) zu analysieren. Patienten und Methoden Eingeschlossen wurden 19 im Rahmen der „low-dose PDT“ belichtete Areale an 16 Augen. Neben der Erhebung von Visus und Metamorphopsien wurden ein „enhanced depth imaging-OCT“ (EDI-OCT) und eine OCT-Angiographie mit Zentrierung auf das bei der „low-dose PDT“ belichtete Areal angefertigt. Im Rahmen der vorliegenden Studie wurden das choriokapilläre Flusssignal sowie die chorioidale Dicke innerhalb eines genormten Bezirks sowohl im Bereich der PDT-Applikation als auch in einem unbeleuchteten Referenzareal in direkter Nähe mit gleicher Exzentrizität in Bezug auf die Fovea centralis retrospektiv ausgewertet. Ergebnisse Es konnten im Mittel eine Abnahme des choriokapillären Flusssignals um 33 % (p < 0,001) im belichteten Areal gegenüber dem Referenzareal sowie eine im Durchschnitt um 71 µm (p = 0,001) verminderte Aderhautdicke im Vergleich zum Referenzareal gezeigt werden; 7 von 10 Patienten beklagten trotz „low-dose PDT“ langfristig Metamorphopsien, jedoch ergab sich durch die Therapie bei fast der Hälfte der Patienten eine Visusverbesserung. Schlussfolgerungen Durch die OCT-Angiographie konnte gezeigt werden, dass die „low-dose PDT“ im Bereich der Choriokapillaris ein vermindertes Blutflusssignal zurücklässt und somit das vaskuläre Remodelling die thrombosebedingte Hypoperfusion nicht gänzlich kompensiert.
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40

Amrut.S. Salunke, Sonali Sunil Tadasarkar, and Adarsh Ramkalap Sharma. "RETINITIS PIGMENTOSA AND ITS AYURVEDIC MANAGEMENT." International Journal of Ayurveda and Pharma Research, July 1, 2021, 62–68. http://dx.doi.org/10.47070/ijapr.v9i5.1919.

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Retinitis pigmentosa (RP) is a group of diseases involving progressive degeneration of photoreceptor cells of retina. Usually, it starts in mid periphery and advancing towards the macula and fovea centralis. Visual symptoms are nyctalopia (night blindness), tubular vision and reduced visual field. Symptoms of RP mostly starts on early teen age and sever visual loss occurs at ages of 40 to 50 years. RP has worldwide prevalence of 1:3000 to 1:7000 people. Males are more affected than female in ratio of 3:2. Nakulandhya and Shleshmavidagdha Drishti explained under Drishtigata Roga in Ayurvedic literature. These two are described as Sannipataja Syadhi and Kaphaj Vyadhi respectively. They have close resemblance with retinitis pigmentosa in their symptomatology. In current era treatment for RP includes Gene therapy, retinal implants, Neurotrophic factor, stem cells, retinal transplants. But these treatment options are not specific and satisfactory and expensive. All these treatments are still in their early stages of research and development. Ayurvedic Panchakarma therapies and Kriyakalpa therapies can help to regulate vitiated Doshas and provide nourishment and strength to ocular tissue. These therapies can help to maintain the existing vision of patient and reduce progression of RP.
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41

Reić, Ina, and Matilda Nikolić. "Vrijeme reakcije na makularno i ekstramakularno projiciranje podražaje različitih kvaliteta." Papers on Philosophy, Psychology, Sociology and Pedagogy 25, no. 2 (April 18, 2018). http://dx.doi.org/10.15291/radovifpsp.2570.

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The investigation of the reaction time to light stimuli of different qualities was launched with the hypothesis that, going by the structure of the retina of the eye, the reaction time will differ according to the place on the retina affected by the stimuli, that is, whether the stimuli is applied onto or outside the macule lutee of the eye’s retina. Two chromatic qualities of stimuli were used: red and blue light as electromagnetic waves with the biggest and smallest wave lengths of the visible part of the specter and white light as the achromatic quality which contains all the wave lengths. Ten people participated in the investigation who, in conditions of greater or smaller illumination, had to react as quickly as possible to different light stimuli, projected as these were onto different angle distances in relation to the retinal fovea centralis. Results show that reaction time increased with the increase of the angle of application of the stimuli, especially starting with thirty degrees and onwards. This corresponds to the surface of the eye’s macule lutee which means that the reaction time to extra-macular stimuli is significantly longer in relation to the macular ones.
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Hu, Kaijiao, Longbao Lv, Hui Huang, Guangnian Yin, Jie Gao, Jianping Liu, Yaying Yang, et al. "A Novel Tree Shrew Model of Chronic Experimental Autoimmune Uveitis and Its Disruptive Application." Frontiers in Immunology 13 (May 27, 2022). http://dx.doi.org/10.3389/fimmu.2022.889596.

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BackgroundPrevious studies have established several animal models for experimental autoimmune uveitis (EAU) in rodents without the fovea centralis in the human retina. This study aimed to develop and explore the application of a novel EAU model in tree shrews with a cone-dominated retina resembling the human fovea.MethodsTree shrews were clinically and pathologically evaluated for the development and characteristics of EAU immunized with six inter-photoreceptor retinoid-binding proteins (IRBPs). IRBP-specific T-cell proliferation and serum cytokine of tree shrews were evaluated to determine the immune responses. Differentially expressed genes (DEGs) were identified in the eyes of tree shrews with EAU by RNA-sequencing. The disruptive effects of the DEG RGS4 inhibitor CCG 203769 and dihydroartemisinin on the EAU were investigated to evaluate the potential application of tree shrew EAU.ResultsIRBP1197–1211 and R14 successfully induced chronic EAU with subretinal deposits and retinal damage in the tree shrews. The immunological characteristics presented the predominant infiltration of microglia/macrophages, dendritic cells, and CD4-T-cells into the uvea and retina and pathogenic T helper (Th) 1 and Th17 responses. The subretinal deposits positively expressed amyloid β-protein (Aβ), CD8, and P2Y purinoceptor 12 (P2RY12). The crucial DEGs in R14-induced EAU, such as P2RY2 and adenylate cyclase 4 (ADCY4), were enriched for several pathways, including inflammatory mediator regulation of transient receptor potential (TRP) channels. The upregulated RGS4 in IRBP-induced EAU was associated with mitogen-activated protein kinase (MAPK) activity. RGS4 inhibition and dihydroartemisinin could significantly alleviate the retinal pathological injuries of IRBP1197-1211-induced EAU by decreasing the expression of CD4 T-cells.ConclusionOur study provides a novel chronic EAU in tree shrews elicited by bovine R14 and tree shrew IRBP1197-1211 characterized by retinal degeneration, retinal damage with subretinal Aβ deposits and microglia/macrophage infiltration, and T-cell response, probably by altering important pathways and genes related to bacterial invasion, inflammatory pain, microglial phagocytosis, and lipid and glucose metabolism. The findings advance the knowledge of the pathogenesis and therapeutics of the fovea-involved visual disturbance in human uveitis.
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