Visual Psychophysics / Physiological Optics - ARVO

More documents

Recommendations

Info

ARVO 2013 Annual Meeting Abstracts by Scientific Section/Group – Visual Psychophysics / Physiological OpticsProgram Number: 4261 Poster Board Number: B0298Presentation Time: 8:30 AM - 10:15 AMThe Dynamic Accommodative Response with the Binocular openfieldautorefractor and a Movable Real TargetShinji Arai 1 , Hiroshi Uozato 1, 2 , Masakazu Hirota 1 . 1 Department ofVisual Science, Kitasato University Graduate School of MedicalSciences, Kanagawa, Japan; 2 Department Orthoptics and VisualSciences, Kitasato University School of Allied Health Science,Kanagawa, Japan.Purpose: To evaluate the dynamic characteristic of accommodationin the open field and real target using new device WMT-1Methods: Fourteen volunteers (6 men and 8 women; mean ±standard deviation age, 23.9 ± 4.0 years; range, 19 to 33 years)participated in our study. All subject had a visual acuity 20/20 orbetter and normal ocular health. Each subject’s accommodativeresponse was measured by target moving system WMT-1 (GrandSeiko Co., Ltd, Hiroshima, Japan) dynamically. The WMT-1 is a newdevice that is connected to the WAM-5500 open-field autorefractor.It can move a target optionally from 0.2 to 1.0 meter and measurerefraction every 0.2 second. We made shape of the cross as a visualtarget, displayed it in iPad (Apple Inc., Cupertino, CA).We evaluated three difference movements that had been programmedon the WMT-1.First, the constant diopter triangle drive. Second, constant velocitytriangle drive. Third, diopter sin drive. We measured dynamicallyaccommodative response in visual target distance from 1.0 meter to0.2 meter. We compared maximum quantity of accommodativeresponse and among three movements.Results: The maximum quantity of accommodative response ofDiopter Sin Drive became larger than Constant Velocity TriangleDrive (p < 0.05, Scheffe test). However, statistical significantlydifference was not found to other comparison.Accommodative response related to movement of visual target.Conclusions: We could measure dynamic characteristic ofaccommodation in the open field and real target using the WMT-1.The accommodation is evaluated at a definite point conventionally.The WMT-1 is useful to evaluate the dynamic characteristic ofaccommodation, because it can measure not only maximum quantityof accommodative response but also process of accommodativeresponse.Alistair P. Curd, Karen M. Hampson, Edward Mallen. BradfordSchool of Optometry and Vision Science, University of Bradford,Bradford, United Kingdom.Purpose: To investigate whether suppression of the accommodationresponse (AR) would be observed when a dioptric stimulusperformed a step-change, followed by an inverted step-change withinthe latency time for AR. Results would be relevant to models ofaccommodation and nearwork.Methods: A monocular adaptive optics apparatus displayed a targetto participants, and accommodation was recorded using a Shack-Hartmann wavefront sensor. A deformable mirror rapidly changedthe dioptric stimulus provided by the target. The baseline vergence ofthe target was −2D at the eye. An initial step-change in the stimuluswas followed by a second, inverted step, before the stimulus returnedto the baseline. Initial steps were of 1D or 2D in either direction;intervals between the steps ranged from 0.05s to 0.5s. The stimulussettings were randomised in order. The six participants (aged 21-26)observed every stimulus condition five times, through their dominanteye. A Badal optometer arrangement was used to eliminate a size cueand audible cues from the system were masked with auditory inputthrough headphones. Timings of the first change in the stimulus wererandomised.Results: Whether accommodation was responding to the first orsecond change in the stimulus affected the peak AR (p
ARVO 2013 Annual Meeting Abstracts by Scientific Section/Group – Visual Psychophysics / Physiological Opticsits change caused by accommodation was calculated based on theacquired image.Results: Repeated measurements were taken in each accommodativestate. Compared with relaxed state (0D), the mean thickness variationaround the central fovea was 7.4957±8.3616 μm at 5Daccommodation. In further study, we will collect more data toanalyze the variations of axial length and retinal thickness.Conclusions: Preliminary result showed that the thickness betweenILM and RPE in macular has a slight change during accommodation.Commercial Relationships: Chuanqing Zhou, None; ShanhuiFan, None; Zhe Chen, None; Xinyu Chai, NoneSupport: the National Basic Research Program of China(2011CB707504), National Natural Science Foundation of China(81171377)Program Number: 4264 Poster Board Number: B0301Presentation Time: 8:30 AM - 10:15 AMThe Effect Of Age On The Lens Ultrastructure DuringAccommodation As Measured Using Slit Lamp Photos AndWave Front AnalysisRebecca K. Zoltoski 1 , Elizabeth Wyles 1 , Jennifer S. Harthan 1 , Jer R.Kuszak 2 . 1 Illinois College of Optometry, Chicago, IL; 2 LensAR,Orlando, FL.Purpose: During dynamic focusing, the shape, as well as the ultrastructureof the lens is changed. We have hypothesized that uniquestructural features and organization of fiber cells enables them tointerface at the sutures resulting in a change in surface curvature ofthe lens, as well as an increase in thickness, allowing near focus tooccur. We are reporting extended data on lens slit lamp photos, OCTof lens thickness changes, and sequential ray tracing analysis of thepatterns associated with the lens sutures to provide additional insightinto the importance of the ultra-structure of the lens in theaccommodative process.Methods: OCT (Visante), wavefront analysis (iTrace), and slitlamp photos (Haag Streit, 16X magnification, dilated eye) werecollected on the right eye of normal subjects, between the ages of 7 -63 (n=30). Accommodation was stimulated using minus lenses infront of the viewing eye in 2.5 D increments until the subject couldno longer clearly view the target. For the photos a prism system wasused to keep the eye appropriately oriented. The objectiveaccommodative response was calculated as the change from adistance measurement refractive value. ImageJ (NIH) was used toanalyze the area of the sutural components. Data were analyzed usingSystat v11 to correlate accommodative response (AR) with totalHOA, SA and the foil patterns, as well as changes in slit lamp sutureareas. Spearman Rank Correlation coefficients and p values arepresented.Results: Lens thickness increases by 0.13 ± 0.05 μm/D duringaccommodation. The total foil aberration pattern was correlated withAR (r2=0.5, p=0.04). There was a decrease in suture band thicknessthat correlated with the AR (r2=-0.5, p
Page 5 and 6:
ARVO 2013 Annual Meeting Abstracts
Page 8 and 9:
Page 10 and 11:
Page 12 and 13:
Page 14 and 15:
Page 16 and 17:
Page 18 and 19:
Page 20 and 21:
Page 22 and 23:
Page 24 and 25:
Page 26 and 27:
Page 28 and 29:
Page 30 and 31:
Page 32 and 33:
Page 34 and 35:
Page 36 and 37:
Page 38 and 39:
Page 40 and 41:
Page 42 and 43:
Page 44 and 45:
Page 46 and 47: ARVO 2013 Annual Meeting Abstracts
Page 130: ARVO 2013 Annual Meeting Abstracts
show all

Visual Psychophysics / Physiological Optics - ARVO

Create successful ePaper yourself

Delete template?

Save as template?