Visual Psychophysics / Physiological Optics - ARVO

ARVO 2013 Annual Meeting Abstracts by Scientific Section/Group – Visual Psychophysics / Physiological Optics/ 10.75%, p=0.06, Wilcoxon test).Conclusions: Differences in the detection of darks and light arerobust, can be demonstrated over a wide range of ages and in patientswith retinal ganglion cell disease caused by glaucoma. The findingthat patients with glaucoma show a 15% reduction in detectionaccuracy raises the question of whether a simple detection test couldbe used to monitor disease progression.Commercial Relationships: Linxi Zhao, None; Mitchell W. Dul,None; Jose M. Alonso, None; Stanley J. Komban, None; QasimZaidi, NoneSupport: EY007556, EY007716, EY013312, EY005253,T35EY020481Program Number: 2769 Poster Board Number: B0023Presentation Time: 8:30 AM - 10:15 AMIs visual exploration training beneficial in tunnel vision?Iliya V. Ivanov, Annika F. Vollmer, Nhung Nguyen, SusanneTrauzettel-Klosinski. University of Tuebingen, Tuebingen, Germany.Purpose: Tunnel vision is a severe peripheral visual field lossimpairing mobility. It has been previously shown that normallysighted subjects exhibit larger horizontal than vertical component ofeye position dispersions (standard deviations) while walking andavoiding obstacles in daily life. However, for patients with tunnelvision caused by retinitis pigmentosa (RP), horizontal and verticalcomponents were not found to be significantly different 1. In thisstudy we wanted to test whether visual exploration training isbeneficial for RP patients, as in patients with homonymoushemianopia 2. Any efficient eye movement training in RP patients,would result in change of eye-movement pattern- larger horizontalthan vertical dispersions.Methods: Patients (n=33) were randomly assigned into three traininggroups: saccadic (experimental), reading (placebo) or crossover(placebo+experimental). In saccadic training condition, computerbasedtraining extended eye-movement exploration outside of theconcentric constriction of the visual field (VF). In reading trainingcondition patients had to read a text that was presented at the centerof the screen, one word at time. To assess any effect of training,mobile eye tracker was used to record eye positions while walking instandardized environment (parkour), before and after training. Wecompared horizontal and vertical eye dispersions of patients in thedifferent experimental groups with a control group of normals (n =10).Results: Comparable with previous findings, patients who hadresidual VF < 15° (from fixation) showed equal horizontal andvertical dispersions before training. After training however, patientswho received saccadic training showed significantly larger horizontaldispersion (p 15° remained the same.Regardless of their residual VF, patients in placebo group did notshow an effect of training: horizontal and vertical dispersionsremained unchanged after training.Conclusions: These findings suggest that visual exploration trainingis highly specific and resulted in significantly increased dynamic VFfor the RP patients with VF < 15°.Commercial Relationships: Iliya V. Ivanov, None; Annika F.Vollmer, None; Nhung Nguyen, None; Susanne Trauzettel-Klosinski, NoneSupport: Kniese Foundation; Funke Foundation; Stiftung AugeProgram Number: 2770 Poster Board Number: B0024Presentation Time: 8:30 AM - 10:15 AMIs Vernier Acuity more Sensitive than Grating Acuity to VisualImpairment in Adolescents?Huizi Kelly Yin 1 , Barry S. Kran 2 , Darick Wright 3 , Donna D. Bent 3 , LiDeng 2 , Dale L. Mayer 2 . 1 Illinois College of Optometry, Chicago, IL;2 New England College of Optometry, Boston, MA; 3 Perkins School,Watertown, MA.Purpose: Vernier acuity, often referred to as a “hyperacuity”, may bemore sensitive than grating acuity in detecting visual deficits such asamblyopia in young children. Thus, we compared vernier acuity(VeA) and grating acuity (GA) tests to recognition acuity (RA) inadolescents with visual impairment, hearing loss, and cognitivedisabilities.Methods: 24 optometry students from the New England College ofOptometry and 10 adolescents (16 eyes) attending Perkins School forthe Blind were tested in each eye for RA (crowded letters), VeA(Drover et al OVS 2010) and GA (Teller Acuity Cards) in 2 sessions.Acuities were analyzed in logMAR. Test-retest reliabilities wereexamined with Bland-Altman method (bias, 95% Limits ofagreement, LOA). To directly compare VeA and GA to RA inadolescents, their raw data were normalized taking the differencefrom the normal value for age (Delta-Normal, ΔN). ΔNs wereanalyzed with correlations and means.Results: Adult mean (SD) logMAR acuities (RE, session 1) were:RA -0.11 (0.05) (20/16); VeA: -0.24 (0.15); GA: -0.09 (0.05). Testretestanalyses of the adolescent data (in logMAR) showed minimalbias and similar 95% LOA (0.66 for RA; 0.69 for VeA; 0.56 for GA).For adults, test-retest 95% LOA for RA was 0.28 logMAR.Correlations of adolescents’ ΔN for VeA and GA with RA (session1)were significant and similar (VeA with RA, r=0.78; GA with RA,r=0.83). Mean ΔNs were also similar and not significantly different(RA: -0.79±0.34; VeA: -0.89 ± 0.44; GA: -0.76±0.31).Conclusions: Test retest reliabilities are similar for RA, VeA and GAtests in a small sample of adolescents with visual impairment andother disabilities. Normalized VeA and GA acuities have a similarrelationship to normalized RA and are not significantly different onaverage. Thus, vernier acuity may not have an advantage over gratingacuity in adolescents with visual impairments due to ocular andneurological causes, who have other disabilities. However, for othercauses of visual deficits, for example, amblyopia, vernier acuity maybe more sensitive than grating acuity.Vernier acuity cards with stimuli, forming a second-order shape of asix-pointed star or a flower (Drover et al 2010). Acknowledgments:Eileen E. Birch, PhD. and Yi-Zhong Wang, PhD. who provided thestimuli.©2013, Copyright by the Association for Research in Vision and Ophthalmology, Inc., all rights reserved. Go to iovs.org to access the version of record. For permissionto reproduce any abstract, contact the ARVO Office at arvo@arvo.org.