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Birch D.G.,Retina Foundation of the Southwest | Weleber R.G.,Oregon Health And Science University | Duncan J.L.,University of California at San Francisco | Jaffe G.J.,Duke University | Tao W.,Neurotech
American Journal of Ophthalmology | Year: 2013

Purpose: To evaluate the safety and effect on visual function of ciliary neurotrophic factor delivered via an intraocular encapsulated cell implant for the treatment of retinitis pigmentosa (RP). Design: Ciliary neurotrophic factor for late-stage retinitis pigmentosa study 3 (CNTF3; n = 65) and ciliary neurotrophic factor for early-stage retinitis pigmentosa study 4 (CNTF4; n = 68) were multicenter, sham-controlled dose-ranging studies. Methods: Patients were randomly assigned to receive a high- or low-dose implant in 1 eye and sham surgery in the fellow eye. The primary endpoints were change in best-corrected visual acuity (BCVA) at 12 months for CNTF3 and change in visual field sensitivity at 12 months for CNTF4. Patients had the choice of retaining or removing the implant at 12 months for CNTF3 and 24 months for CNTF4. Results: There were no serious adverse events related to either the encapsulated cell implant or the surgical procedure. In CNTF3, there was no change in acuity in either ciliary neurotrophic factor- or sham-treated eyes at 1 year. In CNTF4, eyes treated with the high-dose implant showed a significant decrease in sensitivity while no change was seen in sham- and low dose-treated eyes at 12 months. The decrease in sensitivity was reversible upon implant removal. In both studies, ciliary neurotrophic factor treatment resulted in a dose-dependent increase in retinal thickness. Conclusions: Long-term intraocular delivery of ciliary neurotrophic factor is achieved by the encapsulated cell implant. Neither study showed therapeutic benefit in the primary outcome variable. © 2013 Elsevier Inc. All rights reserved.

O'Connor A.R.,University of Liverpool | Birch E.E.,Retina Foundation of the Southwest | Anderson S.,Alder Hey Childrens NHS Foundation Trust | Draper H.,Alder Hey Childrens NHS Foundation Trust
Investigative Ophthalmology and Visual Science | Year: 2010

PURPOSE. Development or restoration of binocular vision is one of the key goals of strabismus management; however, the functional impact of stereoacuity has largely been neglected. METHODS. Subjects aged 10 to 30 years with normal, reduced, or nil stereoacuity performed three tasks: Purdue pegboard (measured how many pegs placed in 30 seconds), bead threading (with two sizes of bead, to increase the difficulty; measured time taken to thread a number of beads), and water pouring (measured both accuracy and time). All tests were undertaken both with and without occlusion of one eye. RESULTS. One hundred forty-three subjects were recruited, 32.9% (n _ 47) with a manifest deviation. Performances on the pegboard and bead tasks were significantly worse in the nil stereoacuity group when compared with that of the normal stereoacuity group. On the large and small bead tasks, those with reduced stereoacuity were better than those with nil stereoacuity (when the Preschool Randot Stereoacuity Test [Stereo Optical Co, Inc., Chicago, IL] results were used to determine stereoacuity levels). Comparison of the short-term monocular conditions (those with normal stereoacuity but occluded) with nil stereoacuity showed that, on all measures, the performance was best in the nil stereoacuity group and was statistically significant for the large and small beads task, irrespective of which test result was used to define the stereoacuity levels. CONCLUSIONS. Performance on motor skills tasks was related to stereoacuity, with subjects with normal stereoacuity performing best on all tests. This quantifiable degradation in performance on some motor skill tasks supports the need to implement management strategies to maximize development of high-grade stereoacuity. © Association for Research in Vision and Ophthalmology.

Felius J.,Retina Foundation of the Southwest | Beauchamp C.L.,Pediatric Ophthalmology and Center for Adult Strabismus | Stager Sr. D.R.,Pediatric Ophthalmology and Center for Adult Strabismus
American Journal of Ophthalmology | Year: 2014

Purpose To investigate the association between visual acuity deficits and fixation instability in children with Down syndrome and nystagmus. Design Prospective cross-sectional study. Methods setting: Institutional. study population:Sixteen children (aged 10 months-14 years) with Down syndrome and nystagmus, and a control group of 93 age-similar children with unassociated infantile nystagmus. observation procedures: Binocular Teller acuity card testing and eye-movement recordings. Fixation stability was quantified using the nystagmus optimal fixation function (NOFF). An exponential model based on results from the control group with unassociated infantile nystagmus was used to relate fixation stability to age-corrected visual acuity deficits. main outcome measures: Binocular grating visual acuity and NOFF. Results Visual acuity was 0.2-0.9 logMAR (20/30-20/174 Snellen equivalent) and corresponded to a 0.4 logMAR (4 lines) mean age-corrected visual acuity deficit. Fixation stability ranged from poor to mildly affected. Although visual acuity deficit was on average 0.17 logMAR larger (P =.005) than predicted by the model, most children had visual acuity deficit within the 95% predictive interval. Conclusions There was a small mean difference between the measured visual acuity deficit and the prediction of the nystagmus model. Although other factors also contribute to visual acuity loss in Down syndrome, nystagmus alone could account for most of the visual acuity deficit in these children. © 2014 BY ELSEVIER INC. ALL RIGHTS RESERVED.

Wang J.,Retina Foundation of the Southwest | Rowan Candy T.,Indiana University Bloomington
Investigative Ophthalmology and Visual Science | Year: 2010

Purpose. The goal of this study was to compare objectively the sensitivity of the accommodation system in human infants and adults under binocular and monocular viewing conditions. Methods. Full-term infants from 2 to 4 months of age and pre-presbyopic adults were presented with a high-contrast cartoon stimulus moving sinusoidally in diopters around a mean position of 2 D (50 cm). Three stimulus amplitudes were used in one trial (0.25, 0.50, and 0.75 D), with unpredictable stimulus motion during each amplitude change. Eccentric photo refraction was used to record accommodative responses at 25 Hz. The stimulus was made monocular by placing an infrared filter over the right eye, to block visible light but pass the near-infrared wavelength of the photo refractor and allow responses to be recorded from both eyes. Results. Fourier analysis was used to determine the accommodative response at the frequency of the stimulus. Significant signal-to-noise ratios indicated that, on average, the 2- to 4-month-old infants generated an accommodative response to at least the 0.75 D amplitude monocular stimulus and the 0.75 and 0.50 D binocular stimuli. Adults responded to the 0.25 D amplitude both binocularly and monocularly. Conclusions. In infants 2 to 4 months of age, the developing visual system compensates for small changes in defocus relative to the typical amounts of hyperopic refractive error found at that age. © Association for Research in Vision and Ophthalmology.

Liu L.,University of Alabama at Birmingham | Wang Y.-Z.,Retina Foundation of the Southwest | Bedell H.E.,University of Houston
Optometry and Vision Science | Year: 2014

Age-related macular degeneration (AMD) is one of the leading causes of severe visual impairment in the United States. Changes in lifestyle can slow the progression of AMD, and new therapies that arrest choroidal neovascularization can preserve vision in patients who progress to the neovascular form of advanced AMD. Appropriate timing is required for these interventions to be optimally effective, which, in turn, depends critically on early diagnosis. Because annual or semiannual eye examinations may not be sufficient to ensure an early diagnosis, the preferred practice for AMD management must include self-monitoring by patients for disease onset or progression. In this review, we discuss a number of visual functions that have been shown to be impaired in eyes with AMD and specify desirable characteristics of visual-function tests that can be used for self-monitoring by populations at risk for AMD. Copyright © 2014 American Academy of Optometry.

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