Visual Acuity and Heterogeneities of Retinal Ganglion Cell Densities and the Tapetum Lucidum of the African Elephant (Loxodonta africana)

2010 ◽  
Vol 75 (4) ◽  
pp. 251-261 ◽  
Author(s):  
John D. Pettigrew ◽  
Adhil Bhagwandin ◽  
Mark Haagensen ◽  
Paul R. Manger
Keyword(s):  
Visual Acuity ◽  
Ganglion Cell ◽  
Retinal Ganglion Cell ◽  
Loxodonta Africana ◽  
African Elephant ◽  
Retinal Ganglion ◽  
Tapetum Lucidum ◽  
Cell Densities

scholarly journals OPTICAL COHERENCE TOMOGRAPHY;

2018 ◽  
Vol 26 (01) ◽  
Author(s):  
Muhammad Shaheer ◽  
Arooj Amjad ◽  
Asima Rafique
Keyword(s):  
Visual Acuity ◽  
Cataract Surgery ◽  
Ganglion Cell ◽  
General Hospital ◽  
Retinal Ganglion Cell ◽  
Cell Complex ◽  
Ganglion Cell Complex ◽  
Retinal Ganglion ◽  
Department Of Ophthalmology ◽  
Retinal Ganglion Cell Complex

ABSTRACT: PURPOSE: To study the changes in Ganglion Cell Complex as measured on OCT after phacoemulsification with intra ocular lens implantation. STUDY DESIGN: Quasi experimental study PLACE AND DURATION OF STUDY: Department of Ophthalmology, Lahore General Hospital, Lahore from 1-3-2017 to 30-4-2018 MATERIALS AND METHODS: Ethical approval of the study was obtained from ‘’Ethical Review Committee’’ of Lahore General Hospital, Lahore. Patients presenting to the Eye OPD Lahore General Hospital were assessed for inclusion and exclusion criteria. All patients (n=64) diagnosed with cataract requiring surgery were included in study. Patients having any coexisting ocular pathology hindering the OCT measurement i.e. Corneal opacity, Vitreous hemorrhage, Retinal detachment were excluded from study. Retinal Ganglion Cell Complex thickness was measured in Superior, Inferior, Supero-Nasal, Supero-Temporal, Infero-Nasal and Infero-Temporal quadrants. Besides that Signal Strength on OCT was also documented. Pre-Operatively, Visual acuity was measured and OCT performed and the findings were recorded on a designed proforma. Post-Operatively, the patients were called for follow-up after one month at which time Visual acuity was again measured and OCT performed and findings recorded in the proforma. All the surgeries were performed by single surgeon. RESULTS: The thickness of Ganglion Cell Complex increased significantly (p<0.001) one month after cataract surgery. CONCLUSION: Cataract surgery does affect the measurement of Retinal Ganglion Cell Complex thickness on OCT.

scholarly journals Intraocular injection of ES cell-derived neural progenitors improve visual function in retinal ganglion cell-depleted mouse models

2017 ◽  
Author(s):  
Mundackal Sivaraman Divya ◽  
Vazhanthodi Abdul Rasheed ◽  
Tiffany Schmidt ◽  
Soundararajan Lalitha ◽  
Samer Hattar ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Ganglion Cell ◽  
Retinal Ganglion Cell ◽  
Mouse Models ◽  
Visual Function ◽  
Functional Integration ◽  
Embryonic Stem ◽  
Neural Progenitors ◽  
Retinal Ganglion ◽  
Es Cell

AbstractRetinal ganglion cells (RGC) transplantation is a promising strategy to restore visual function resulting from irreversible RGC degeneration occurring in glaucoma or inherited optic neuropathies. We previously demonstrated FGF2 induced differentiation of mouse embryonic stem cells (ESC) to RGC lineage, capable of retinal Ganglion Cell Layer (GCL) integration upon transplantation in mice. Here, we evaluated possible improvement of visual function by transplantation of ES cell derived neural progenitors in RGC depleted glaucoma mice models. ESC derived neural progenitors (ES-NP) were transplanted into NMDA (N-Methyl-D-Aspartate) injected, RGC-ablated mouse models and a pre-clinical glaucoma mouse model (DBA/2J) having sustained higher intra ocular pressure (IOP). Visual acuity and functional integration was evaluated by behavioural experiments and immunohistochemistry, respectively. GFP-expressing ES-NPs transplanted in NMDA-injected RGC-depleted mice differentiated into RGC lineage and possibly integrating into GCL. An improvement in visual acuity was observed after two months of transplantation, when compared to the pre-transplantation values. Expression of c-Fos in the transplanted cells, upon light induction, further suggests functional integration into the host retinal circuitry. However, the transplanted cells did not send axonal projections into optic nerve. Transplantation experiments in DBA/2J mouse showed no significant improvement in visual functions, possibly due to both host and transplanted retinal cell death which could be due to an inherent high IOP. We showed that, transplantation of ES-NPs into the retina of RGC-ablated mouse models could survive, differentiate to RGC lineage, and possibly integrate into GCL to improve visual function. However, for the survival of transplanted cells in glaucoma, strategies to control the IOP are warranted.

The Retinal Ganglion Cell Layer and Visual Acuity of the Camel

2001 ◽  
Vol 58 (1) ◽  
pp. 15-27 ◽  
Author(s):  
Alison Harman ◽  
Jody Dann ◽  
Alicia Ahmat ◽  
Todd Macuda ◽  
Kevin Johnston ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Ganglion Cell ◽  
Retinal Ganglion Cell ◽  
Ganglion Cell Layer ◽  
Cell Layer ◽  
Retinal Ganglion ◽  
Retinal Ganglion Cell Layer

scholarly journals Retinal ganglion cell distribution and visual acuity in alpacas (Vicugna pacos)

2013 ◽  
Vol 18 (1) ◽  
pp. 35-42 ◽  
Author(s):  
Hsiao-Hui Wang ◽  
Shannon K. Gallagher ◽  
Stacey R. Byers ◽  
James E. Madl ◽  
Juliet R. Gionfriddo
Keyword(s):  
Visual Acuity ◽  
Ganglion Cell ◽  
Retinal Ganglion Cell ◽  
Retinal Ganglion ◽  
Cell Distribution ◽  
Vicugna Pacos

scholarly journals Frequency of retinal changes in patients with COVID-19: an observational study

2020 ◽  
Vol 11 (2) ◽  
pp. 40-49
Author(s):  
A. R. Illarionova ◽  
O. M. Potapova ◽  
O. A. Kosareva ◽  
Yu. R. Kuznetsova
Keyword(s):  
Visual Acuity ◽  
Ganglion Cell ◽  
Retinal Ganglion Cell ◽  
Ganglion Cell Layer ◽  
De Novo ◽  
Cell Layer ◽  
Plexiform Layer ◽  
Retinal Ganglion ◽  
Visual Functions ◽  
Retinal Ganglion Cell Layer

In order to enter cells, SARS-CoV-2 virus uses the angiotensin-converting enzyme 2 receptor that is also expressed in retina. Aim. Determination of the frequency and nature of retinal changes, evaluation of visual functions in patients who have got over COVID-19. Materials and methods. This observational research includes 31 patients aged from 28 to 79 that got over COVID-19 (with severity according to computed tomography (CT): 1–3) in the period from 15 to 40 days before the research. Standard ophthalmological examination and optical coherence tomography (OCT) were performed; visual acuity measurement and threshold static perimetry were used to assess visual functions.Results. Pathology of the ocular surface wasn’t detected. Ophthalmoscopy revealed retinal changes in only one patient. At OCT, 27 (87%) patients proved to have de novo changes in the retinal neuroepithelium at the level of the internal plexiform layer and the retinal ganglion cell layer in the form of hyper-reflective polymorphic foci with clear borders; 18 (67%) patients had monocular lesions. The maximum corrected visual acuity didn’t differ from the previously defined one; no violations of retinal light sensitivity were detected. No association was found between the severity of CT lung changes and retinal changes. The detected retinal changes weren’t associated with symptoms of anosmia (hyposmia) and ageusia. OCT repeated after 12–15 days showed no dynamics of hyperreflective foci: they remained unchanged in their shape, echogenicity and size. Conclusion. De novo changes in retinal neuroepithelium at the level of the inner plexiform layer and the retinal ganglion cell layer were detected according to OCT data in 87% of patients who had undergone COVID-19. Anatomical changes in the retina weren’t manifested by functional visual disturbances. There is no association of retinal changes with lesions of I and IX cranial nerve pairs.

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