Visual Psychophysics / Physiological Optics - ARVO

ARVO 2013 Annual Meeting Abstracts by Scientific Section/Group – Visual Psychophysics / Physiological Opticsand primary posterior chamber intraocular lens implantation betweenFebruary 1992 and December 2009. In all patients, stereoacuity wasassessed using the Titmus test at the last follow-up period ofminimum 2 years after surgery. Patients were divided into two groupsaccording to the extent of stereoacuity: Group 1 (n=42) hadstereoacuity values ≤100 sec/arc and Group 2 (n=68) values >100sec/arc. The values of ten parameters associated with stereoacuitywere measured in each group: Cataract types, preoperative bestcorrected visual acuity (BCVA) of the affected eyes, between-eyedifference in BCVA, age at cataract surgery, operative method, aftercataracts,postoperative strabismus, postoperative BCVA of theaffected eyes, between-eye difference in BCVA, and anisometropia.Results: The extent of stereoacuity was significantly associated withboth operative method and after-cataract (P=0.000 and P=0.016,respectively). All patients in whom the posterior capsule waspreserved, had poor stereoacuity >100 sec/arc. Significantcorrelations with the extent of stereoacuity were found withpostoperative strabismus (P=0.048), postoperative BCVA of theaffected eyes (P=0.002), anisometropia (P=0.034).Conclusions: Postoperative stereoacuity was better in patients whounderwent either optic capture or anterior vitrectomy after posteriorcontinuous curvilinear capsulorhexis, and who didn’t develop aftercataractsor strabismus postoperatively. Furthermore, postoperativeBCVA of the affected eyes, and anisometropia influenced thestereoacuity of the patients surgically treated for unilateraldevelopmental pediatric cataracts.Commercial Relationships: Soo Jung Lee, None; Nam Eok Kim,None; Jung Min Park, NoneProgram Number: 1521 Poster Board Number: B0307Presentation Time: 8:30 AM - 10:15 AMDo Bangerter filters promote binocular function in amblyopes?Daming Deng 1 , Jinrong LI 1, 2 , Benjamin Thompson 3 , Minbin Yu 1, 2 ,Robert F. Hess 4 . 1 State Key Laboratory of Ophthalmology,Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou,China; 2 Department of Optometry and Vision Science, Sun Yat-senUniversity, Guangzhou, China; 3 Department of Optometry andVision Science, University of Auckland, Auckland, New Zealand;4 Department of Ophthalmology, McGill University, Montreal, QC,Canada.Purpose: Bangerter foils have become an alternative treatmentregimen for amblyopia penalization. We have previously found thatwhile Bangerter foils can penalize the normal eye, they do so in amanner that is not graded. In this study, we investigated whetherBangerter foils promote binocular function within the amblyopicvisual system.Methods: Suppression thresholds were measured for 17 amblyopesusing our previously established “balance point” protocol combinedwith a Gabor direction discrimination task. We compared normalbinocular viewing with viewing conditions where the fellow fixingeye was penalized with 0.8, 0.6, 0.4 and 0.2 strenght Bangerter foils.In addition, the effect of Bangerter filters on suppression thresholdsfor patients was compared to results from 10 control observers.Results: The 0.8, 0.6 and 0.4 labeled foils did not influencesuppression in the amblyopic observers. The 0.2 Bangerter foilreduced suppression thresholds and a binocular balance point wasobtained in 14 out of the 17 subjects.Conclusions: Bangerter foils do not gradually induce binocularfacilitation. The 0.8 to 0.4 strength Bangerter foils did not predictablyshift the binocular status of amblyopes. Only the most extreme foiltested, labeled 0.2, reduced suppression among the amblyopicsubjects. Care should be taken when prescribing Bangerter foils inclinical practice.Commercial Relationships: Daming Deng, None; Jinrong LI,None; Benjamin Thompson, US12528934 (P), US8006372B2 (P);Minbin Yu, None; Robert F. Hess, NoneSupport: JRL was supported by The Thrasher Research Fund forEarly Career Award, the Fundamental Research Funds of State KeyLaboratory of Ophthalmology, Sun Yat-sen University and theGuangdong Province Medical Science Research Grant (B2011105).DDM was supported by the Guangdong Province InternationalCollaboration Project Grant (2010B050100014).Program Number: 1522 Poster Board Number: B0308Presentation Time: 8:30 AM - 10:15 AMOptimizing binocular vision of pseudophakes with uncorrectedastigmatismVeerendranath Pesala 1 , Prashant Garg 2 , Shrikant R. Bharadwaj 1 .1 Prof. Brien Holden Eye Research Centre, L V Prasad Eye Institute,Hyderabad, India; 2 Cornea and anterior segment services, L V PrasadEye Institute, Hyderabad, India.Purpose: Uncorrected astigmatism improves monocular near acuityof pseudophakes, but with an associated loss in distance vision. Theimpact of uncorrected astigmatism on binocularity of these eyeshowever remains unknown. This study determined combinations ofastigmatism in the two eyes that simultaneously optimize binoculardistance and near resolution acuity and stereoacuity of bilateralpseudophakes with monofocal IOL implants.Methods: Binocular distance (3m) and near (40cm) logMAR acuityand random-dot stereoacuity (40cm) was measured in 13 emmetropicpseudophakes with 10 different combinations of astigmatism inducedin random order before the two eyes. Three strategies were chosensuch that one eye had I) no astigmatism or II) 1D simple myopic orIII) 1D simple hyperopic astigmatism at 90° while the fellow eye hada) the same error or that with b) orthogonal axis (180°) or c) differentmagnitude (2.5D) or d) opposite polarity (-1D).Results: For all combinations of induced astigmatism, the mean(±1SEM) distance logMAR acuity (0.03±0.03) did not deterioratesignificantly from the best-corrected condition (-0.08±0.02) (p=0.32).Near logMAR acuity and stereoacuity were in-between theuncorrected (N VA : 0.59±0.05; Stereo: 232.9±33.9arc sec) and bestcorrected(N VA : 0.18±0.02; Stereo: 60.9±10.2arc sec) conditions forall myopic astigmatic combinations (Ib & c and IIa - c) and same orworse than the uncorrected condition for hyperopic astigmaticcombinations (Id, IId & IIIa - c) (p=0.003 to 0.36 for all). Alloutcomes variables were closest to their respective best-correctedvalues for combination IIc (OD: ±/+1.0x90°; OS: ±/+2.5x90°; D VA :0.12±0.02; N VA : 0.38±0.03; Stereo: 82.6±8.05arc sec), followed byIIa (OU: ±/+1.0x90; D VA : 0.04±0.02; N VA : 0.43±0.05; Stereo:104.5±13.5arc sec) and Ib. Stereoacuity was worse with orthogonalaxes (IIb) than with parallel axes of myopic astigmatism (IIa) in thetwo eyes (p=0.002).Conclusions: Binocular near logMAR and stereo acuity of bilateralpseudophakes can be simultaneously optimized without hinderingdistance vision using combinations of myopic astigmatism in the twoeyes. Leaving such combinations uncorrected after cataract surgerymay be a viable alternative to sphero-cylindrical bifocals inoptimizing the overall binocular visual experience of the patient.Combinations with astigmatism with orthogonal axes in the two eyesor with hyperopia deteriorate near vision of pseudophakes.Commercial Relationships: Veerendranath Pesala, None;Prashant Garg, None; Shrikant R. Bharadwaj, NoneSupport: Department of BioTechnology RamalingaswamiFellowship, Govt. of India.Program Number: 1523 Poster Board Number: B0309©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.