Strabismus is a major cause of visual disability in the young, affecting 3 to 4 percent of children within the first six years of life. The developmental consequences of strabismus may be mitigated by surgical intervention during the sensitive period for the development of binocular vision. Functional binocular vision is, however, extremely vulnerable to abnormal early visual experience and, rather than normal binocular vision, the majority of children treated for strabismus develop a form of abnormal sensory binocular vision (the monofixation syndrome) that is characterized by foveal suppression and reduced stereoacuity. Although the clinical characteristics of the monofixation syndrome are well- known, little is known about many fundamental properties of binocular vision following surgical eye alignment in infants. The broad objective of the proposed research is to investigate the alterations of motor and sensory fusion caused by a period of strabismus during infancy. A macaque monkey model, which demonstrates many of the abnormalities of binocular vision usually associated with the monofixation syndrome, has been developed and will be used for a series of psychophysical investigations of functional binocular vision. Specifically, investigations will be conducted to obtain quantitative descriptions of fine and coarse control of disparity vergence, the area and depth of suppression during binocular vision, and stereoscopic depth perception with local and global stereopsis. The results of these investigations should lead to an understanding of the mechanisms underlying the imprecision of disparity vergence, the phenomenon of clinical suppression and the reduced stereoacuity of patients with the monofixation syndrome. A better understanding of the mechanisms that fail to fully recover when interocular alignment is re-established during infancy should, in turn, suggest treatments to enhance the post- surgical recovery of binocular vision in strabismic children.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
5R01EY001139-24
Application #
2856880
Study Section
Visual Sciences B Study Section (VISB)
Project Start
1978-01-01
Project End
2000-12-31
Budget Start
1999-01-01
Budget End
1999-12-31
Support Year
24
Fiscal Year
1999
Total Cost
Indirect Cost
Name
University of Houston
Department
Ophthalmology
Type
Schools of Optometry/Ophthalmol
DUNS #
800771594
City
Houston
State
TX
Country
United States
Zip Code
77204
Patel, Nimesh; McAllister, Faith; Pardon, Laura et al. (2018) The effects of graded intraocular pressure challenge on the optic nerve head. Exp Eye Res 169:79-90
McAllister, Faith; Harwerth, Ronald; Patel, Nimesh (2018) Assessing the True Intraocular Pressure in the Non-human Primate. Optom Vis Sci 95:113-119
Patel, Nimesh B; Hung, Li-Fang; Harwerth, Ronald S (2017) Postnatal maturation of the fovea in Macaca mulatta using optical coherence tomography. Exp Eye Res 164:8-21
Ivers, Kevin M; Sredar, Nripun; Patel, Nimesh B et al. (2015) In Vivo Changes in Lamina Cribrosa Microarchitecture and Optic Nerve Head Structure in Early Experimental Glaucoma. PLoS One 10:e0134223
Patel, Nimesh B; Sullivan-Mee, Michael; Harwerth, Ronald S (2014) The relationship between retinal nerve fiber layer thickness and optic nerve head neuroretinal rim tissue in glaucoma. Invest Ophthalmol Vis Sci 55:6802-16
Patel, Nimesh B; Lim, Mimi; Gajjar, Avni et al. (2014) Age-associated changes in the retinal nerve fiber layer and optic nerve head. Invest Ophthalmol Vis Sci 55:5134-43
Luo, Xunda; Patel, Nimesh B; Rajagopalan, Lakshmi P et al. (2014) Relation between macular retinal ganglion cell/inner plexiform layer thickness and multifocal electroretinogram measures in experimental glaucoma. Invest Ophthalmol Vis Sci 55:4512-24
Hanlon, Samuel D; Smith, C Wayne; Sauter, Marika N et al. (2014) Integrin-dependent neutrophil migration in the injured mouse cornea. Exp Eye Res 120:61-70
Patel, Nimesh B; Garcia, Brenda; Harwerth, Ronald S (2012) Influence of anterior segment power on the scan path and RNFL thickness using SD-OCT. Invest Ophthalmol Vis Sci 53:5788-98
Wheat, Joe L; Rangaswamy, Nalini V; Harwerth, Ronald S (2012) Correlating RNFL thickness by OCT with perimetric sensitivity in glaucoma patients. J Glaucoma 21:95-101

Showing the most recent 10 out of 73 publications