Name: a standardized obstacle course for assessment of visual function in ultra low vision and artificial vision
Uploaded: 2014-02-11T16:30:00
Description: Watch this Scientific Journal Video about A Standardized Obstacle Course for Assessment of Visual Function in Ultra Low Vision and Artificial Vision at JoVE.com

DCED State of Pennsylvania

1. Course Construction
<ol>
	<li>Install course floor. Course dimensions are 40 ft long by 7 ft wide consisting of 280 1 ft2 portable floor tiles (beige event floor tiles). Place with black trim around perimeter only (Figure 1).</li>
	<li>Paint the adjacent walls to match the floor tiles creating a somewhat monochromatic environment. Colors we used with greyscale values are provided (Table 5). If the specific colors are not available, we recommend taking a tile to a hardware...

<ol>
	<li>Applegate, W. B., Miller, S. T., Elam, J. T., Freeman, J. M., Wood, T. O., Gettlefinger, T. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Impact+of+cataract+surgery+with+lens+implantation+on+vision+and+physical+function+in+elderly+patients.">Impact of cataract surgery with lens implantation on vision and physical function in elderly patients.</a> JAMA. 257 (8), 1064-1066 (1987).</li><li>Ebert, E. M., Fine, A. M., Markowitz, J., Maguire, M. G., Starr, J. S., Fine, S. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+vision+in+patients+with+neovascular+maculopathy+and+poor+visual+acuity.">Functional vision in patients with neovascular maculopathy and poor visual acuity.</a> Arch. Ophthalmol. 104 (7), 1009-1012 (1986).</li><li>Dougherty, B. E., Martin, S. R., Kelly, C. B., Jones, L. A., Raasch, T. W., Bullimore, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+a+battery+of+functional+tests+for+low+vision.">Development of a battery of functional tests for low vision.</a> Optom. Vis. Sci. 86 (8), 955-963 (2009).</li><li>Alexander, M. F., Maguire, M. G., Lietman, T. M., Snyder, J. R., Elman, M. J., Fine, S. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assessment+of+visual+function+in+patients+with+age-related+macular+degeneration+and+low+visual+acuity.">Assessment of visual function in patients with age-related macular degeneration and low visual acuity.</a> Arch. Ophthalmol. 106 (11), 1543-1547 (1988).</li><li>Ross, C. K., Stelmack, J. A., Stelmack, T. R., Fraim, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preliminary+examination+of+the+reliability+and+relation+to+clinical+state+of+a+measure+of+low+vision+patient+functional+status.">Preliminary examination of the reliability and relation to clinical state of a measure of low vision patient functional status.</a> Optom. Vis. Sci. 68 (12), 918-923 (1991).</li><li>Bullimore, M. A., Bailey, I. L., Wacker, R. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Face+recognition+in+age-related+maculopathy.">Face recognition in age-related maculopathy.</a> Invest. Ophthalmol. Vis. Sci. 32 (7), 2020-2029 (1991).</li><li>Turco, P. D., Connolly, J., McCabe, P., Glynn, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assessment+of+functional+vision+performance:+a+new+test+for+low+vision+patients.">Assessment of functional vision performance: a new test for low vision patients.</a> Ophthalmic. Epidemiol. 1 (1), 15-25 (1994).</li><li>Bittner, A. K., Jeter, P., Dagnelie, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Grating+acuity+and+contrast+tests+for+clinical+trials+of+severe+vision+loss.">Grating acuity and contrast tests for clinical trials of severe vision loss.</a> Optom. Vis. Sci. 88 (10), 1153-1163 (2011).</li><li>West, S. K., Rubin, G. S., Munoz, B., Abraham, D., Fried, L. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assessing+functional+status:+correlation+between+performance+on+tasks+conducted+in+a+clinic+setting+and+performance+on+the+same+task+conducted+at+home.">Assessing functional status: correlation between performance on tasks conducted in a clinic setting and performance on the same task conducted at home.</a> J. Gerontol. A Biol. Sci. Med. Sci. 52 (4), 209-217 (1997).</li><li>Owsley, C., McGwin, G., Sloane, M. E., Stalvey, B. T., Wells, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Timed+instrumental+activities+of+daily+living+tasks:+relationship+to+visual+function+in+older+adults.">Timed instrumental activities of daily living tasks: relationship to visual function in older adults.</a> Optom. Vis. Sci. 78 (5), 350-359 (2001).</li><li>Mangione, C. M., Lee, P. P., Gutierrez, P. R., Spritzer, K., Berry, S., Hays, R. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=National+Eye+Institute+Visual+Function+Questionnaire+Field+Test+Investigators.+Development+of+the+25-item+National+Eye+Institute+Visual+Function+Questionnaire.">National Eye Institute Visual Function Questionnaire Field Test Investigators. Development of the 25-item National Eye Institute Visual Function Questionnaire.</a> Arch. Ophthalmol. 119 (7), 1050-1058 (2001).</li><li>Massof, R. W., Rubin, G. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Visual+function+assessment+questionnaires.">Visual function assessment questionnaires.</a> Surv. Ophthalmology. 45 (6), 531-548 (2001).</li><li>Massof, R. W., Fletcher, D. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evaluation+of+the+NEI+visual+functioning+questionnaire+as+an+interval+measure+of+visual+ability+in+low+vision.">Evaluation of the NEI visual functioning questionnaire as an interval measure of visual ability in low vision.</a> Vision Res. 41, 397-413 (2001).</li><li>Stelmack, J. A., Stelmack, T. R., Massof, R. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measuring+low-vision+rehabilitation+outcomes+with+the+NEI+VFQ-25.">Measuring low-vision rehabilitation outcomes with the NEI VFQ-25.</a> Invest. Ophthalmol Vis Sci. 43 (9), 2859-2868 (2002).</li><li>Stelmack, J. A., Szlyk, J. P., Stelmack, T. R., Demers-Turco, P., Williams, R. T., Moran, D., Massof, R. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Psychometric+properties+of+the+Veterans+Affairs+Low-Vision+Visual+Functioning+Questionnaire.">Psychometric properties of the Veterans Affairs Low-Vision Visual Functioning Questionnaire.</a> Invest. Ophthalmol. Vis. Sci. 45 (11), 3919-3928 (2004).</li><li>Velikay-Parel, M., Ivastinovic, D., Koch, M., Hornig, R., Dagnelie, G., Richard, G., Langmann, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Repeated+mobility+testing+for+later+artificial+visual+function+evaluation.">Repeated mobility testing for later artificial visual function evaluation.</a> J. Neural. Eng. 4 (1), 102-107 (2007).</li><li>Geruschat, D. R., Bittner, A. K., Dagnelie, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Orientation+and+mobility+assessment+in+retinal+prosthetic+clinical+trials.">Orientation and mobility assessment in retinal prosthetic clinical trials.</a> Optom. Vis. Sci. 89 (9), 1308-1315 (2012).</li><li>Chader, G. J., Weiland, J., Humayun, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Artificial+vision:+needs,+functioning,+and+testing+of+a+retinal+electronic+prosthesis.">Artificial vision: needs, functioning, and testing of a retinal electronic prosthesis.</a> Prog. Brain Res. 175, 317-332 (2009).</li><li>Sachs, H. G., Veit-Peter, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Retinal+replacement--the+development+of+microelectronic+retinal+prostheses--experience+with+subretinal+implants+and+new+aspects.">Retinal replacement--the development of microelectronic retinal prostheses--experience with subretinal implants and new aspects.</a> Graefes Arch. Clin. Exp. Ophthalmol. 242 (8), 717-723 (2004).</li><li>Alteheld, N., Roessler, G., Walter, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Towards+the+bionic+eye--the+retina+implant:+surgical,+opthalmological+and+histopathological+perspectives.">Towards the bionic eye--the retina implant: surgical, opthalmological and histopathological perspectives.</a> Acta Neurochir. Suppl. 97 (2), 487-493 (2007).</li><li>Benav, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Restoration+of+useful+vision+up+to+letter+recognition+capabilities+using+subretinal+microphotodiodes).">Restoration of useful vision up to letter recognition capabilities using subretinal microphotodiodes).</a> Conf. Proc. IEEE Eng. Med. Biol. Soc. , 5919-5922 (2010).</li><li>Rizzo, J. F., Wyatt, J., Loewenstein, J., Kelly, S., Shire, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Perceptual+efficacy+of+electrical+stimulation+of+human+retina+with+a+microelectrode+array+during+short-term+surgical+trials.">Perceptual efficacy of electrical stimulation of human retina with a microelectrode array during short-term surgical trials.</a> Invest. Ophthalmol. Vis. Sci. 44 (12), 5362-5369 (2003).</li><li>Rizzo, J. F., Wyatt, J., Loewenstein, J., Kelly, S., Shire, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Methods+and+perceptual+thresholds+for+short-term+electrical+stimulation+of+human+retina+with+microelectrode+arrays.">Methods and perceptual thresholds for short-term electrical stimulation of human retina with microelectrode arrays.</a> Invest. Ophthalmol. Vis. Sci. 44 (12), 5355-5361 (2003).</li><li>Humayun, M. S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Argus+II+Study+Group.+Interim+results+from+the+international+trial+of+Second+Sight's+visual+prosthesis.">Argus II Study Group. Interim results from the international trial of Second Sight's visual prosthesis.</a> Ophthalmology. 119 (4), 779-788 (2012).</li><li>Danilov, Y., Tyler, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Brainport:+an+alternative+input+to+the+brain.">Brainport: an alternative input to the brain.</a> J. Integr. Neurosci. 4 (4), 537-550 (2005).</li><li>Merabet, L. B., Battelli, L., Obretenova, S., Maguire, S., Meijer, P., Pascual-Leone, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+recruitment+of+visual+cortex+for+sound+encoded+object+identification+in+the+blind.">Functional recruitment of visual cortex for sound encoded object identification in the blind.</a> Neuroreport. 20 (2), 132-138 (2009).</li><li>Arfken, C. L., Lach, H. W., McGee, S., Birge, S. J., Miller, J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Visual+Acuity,+Visual+Disabilities+and+Falling+in+the+Elderly.">Visual Acuity, Visual Disabilities and Falling in the Elderly.</a> J. Aging Health. 6 (38), 38-50 (1994).</li><li>Lovie-Kitchin, J., Mainstone, J. C., Robinson, J., Brown, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=What+areas+of+the+visual+field+are+most+important+for+mobility+in+low+vision+patients.">What areas of the visual field are most important for mobility in low vision patients.</a> Clin. Vis. Sci. 5 (3), 249-263 (1990).</li><li>Hassan, S. E., Lovie-Kitchin, J., Woods, R. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vision+and+mobility+performance+of+subjects+with+age-related+macular+degeneration.">Vision and mobility performance of subjects with age-related macular degeneration.</a> Optom. Vis. Sci. 79 (11), 697-707 (2002).</li><li>Leat, S., Lovie-Kitchin, J. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measureing+mobility+performance:+experience+gained+in+designing+a+mobility+course.">Measureing mobility performance: experience gained in designing a mobility course.</a> Clin. Exp. Optom. 89 (4), 215-228 (2006).</li><li>Marron, J. A., Bailey, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Visual+factors+and+orientation-mobility+performance.">Visual factors and orientation-mobility performance.</a> Am. J. Optom. Physiol. Opt. 59 (5), 413-426 (1982).</li><li>Clark-Carter, D. D., Heyes, A. D., Howarth, C. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+efficiency+and+walking+speed+of+visually+impaired+people.">The efficiency and walking speed of visually impaired people.</a> Ergonomics. 29 (6), 779-789 (1986).</li><li>Fryan, C. D., Gu, Q., Ogden, C. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Division+of+Health+and+Nutrition+Examination+Surveys.+Anthropometric+Reference+Data+for+Children+and+Adults+United+States+2007-2010.">Division of Health and Nutrition Examination Surveys. Anthropometric Reference Data for Children and Adults United States 2007-2010.</a> Vital and Health Statistics Series. 11 (252), 20-22 (2012).</li><li>Maguire, A. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Age-dependent+effects+of+RPE65+gene+therapy+for+Leber's+congenital+amaurosis:+a+phase+1+dose-escalation+trial.">Age-dependent effects of RPE65 gene therapy for Leber's congenital amaurosis: a phase 1 dose-escalation trial.</a> Lancet. 374 (9701), 1597-1605 (2009).</li></ol>

We describe an indoor, portable, easily reproducible, and relatively inexpensive course that can be used to evaluate obstacle avoidance in persons who are blind or have low vision. Most current obstacle course designs and tests (i.e. TUGS) are difficult to compare across sites and observers, or are permanent instillations which cannot readily be performed at alternate locations16,17,30. Our goal was to create a course that could be standardized for use at different locations and with different observe...

Low vision rehabilitation assessments must determine whether intervention results in improvement in function. Performance metrics typically involve computer based&#160;reading&#160;or functional assessments1-9&#160;as well as quality of life questionnaires10-15. Being able to also assess the low vision patient&#39;s ability to navigate around obstacles might also provide clues to functional improvements18&#160;particularly in the case of artificial vision devices. Geruschat et al. recently published navigation outcomes with a retinal implant chip, highlighting the need for a standard metric in this area17. Currently there are no widely accepted, objective, validated, and comprehensive standards for determining capacity for obstacle avoidance.
Development of a functional test that would correlate to navigation performance for persons with low vision or &#34;ultra low vision&#34; as produced by artificial vision would be desirable, but has remained an elusive goal. The burgeoning field of artificial vision devices such as retinal implant chips18-24&#160;or sensory substitution devices such as the BrainPort 25&#160;and The vOICe26, necessitates a test of obstacle avoidance that might correlate to increased navigational abilities conferred by these devices. Such an assessment would not only allow subjects to understand their own limitations as they traverse their surroundings, but might provide a means for measuring improvement with orientation and mobility training or between iterations of vision enhancement prototype devices. Ideally, there might be some ability to assess an individual&#39;s risk for fall accidents27.
Our goal was to create an obstacle course that would be useful for evaluation of navigation ability in patients using artificial vision devices and transferrable to the field of low vision in general. A review of the published literature on obstacle courses and visual impairment was undertaken using the PubMed database. There have been numerous attempts at creating standardized obstacle courses16,17,28-31,34. Most of these are not portable in the sense that it would be difficult to exactly reproduce the setting, particularly for outdoor courses. Maguire et al. describe obstacle course which is used to show mobility performance in patients with Leber&#39;s Congenital Amaurosis. This course has the benefit of being portable and small, but it is not clear whether different iterations have been made available to prevent memorization effects, nor are there any provisions for obstacles which are not on the floor, texture changes, or stepovers. Leat provides an incisive description of potential pitfalls in designing a course and puts forth a description of an outdoor course which unfortunately would not be able to be reproduced exactly in an alternative location30. Velikay-Parel et al. described a mobility test for use with retinal implant chips. This design had the benefit of being portable and simple to execute. While this course could be reproduced at an alternative site, no specific details on course construction are provided. Moreover, and more concerning was that they showed the learning effect reached asymptotic levels due to course familiarity, therefore being able to prevent course memorization altogether might eliminate the concern for loss of learning effect over time18. None of the courses described so far have been widely adopted by the low-vision or rehabilitation communities.
The authors subsequently consulted with a team of six low vision occupational therapists and orientation and mobility specialists from the Western Pennsylvania School for Blind Children (Pittsburgh, PA) and the Blind and Vision Services Rehabilitation of Pittsburgh (Homestead, PA) regarding proposed course design. Desirable attributes of a functional obstacle course identified included: Portability for easy assembly/disassembly and storage, flexibility to test under both dim and bright lighting conditions, and to mirror &#34;real life&#34; situations by including obstacles that represent objects in a patient&#39;s home environment that are sturdy enough to withstand repeated collision while being ductile in order to prevent patient injury. In addition it was deemed necessary to have several types of environments designed in such as way so that when administered in a randomized order prevents course memorization. In addition, the course should demonstrate reproducible results in multiple settings, have strong inter and intra rater reliability and be an objective measure of spatial awareness.
The culmination of this effort was development of an obstacle course which could reasonably be expected to be reproduced in a standard institutional hallway. The course is designed to test different skill sets, all important for navigation. Each level of the course attempts to focus several particular types of obstacles encountered in everyday navigation activities. The first course evaluates the ability to navigate through relatively high contrast targets that are all placed on the floor, but requires a large number of turns. The second course evaluates the ability to navigate through obstacles that are both high and low contrast, floor texture changes, and objects suspended in air. The final course evaluates the ability to navigate Styrofoam obstacles that are low contrast, surface glare changes on the floor, the addition of nonStyrofoam obstacles (fabric), floor tile color changes, obstacles that must be stepped over, and obstacles that are not on the floor. The courses are labeled 1, 2, and 3 for ease of labeling, but this designation should not be construed as increasing in level of difficulty. Within each level, there are three versions of the course, which can be randomized to prevent course memorization.

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			<td height="35" style="height:35px;width:216px;">Event Floor Tiles, beige</td>
			<td style="width:192px;">Snaplock Industries, Salt Lake City UT</td>
			<td style="width:119px;"></td>
			<td style="width:163px;">Beige</td>
		</tr>
		<tr height="35">
			<td height="35" style="height:35px;width:216px;">Event Floor Tiles, black trim</td>
			<td style="width:192px;">Snaplock Industries, Salt Lake City UT</td>
			<td style="width:119px;"></td>
			<td style="width:163px;">Male loop</td>
		</tr>
		<tr height="35">
			<td height="35" style="height:35px;width:216px;">Event Floor Tiles, black trim</td>
			<td style="width:192px;">Snaplock Industries, Salt Lake City UT</td>
			<td style="width:119px;"></td>
			<td style="width:163px;">Female loop</td>
		</tr>
		<tr height="35">
			<td height="35" style="height:35px;width:216px;">Event Floor Tiles, Edging</td>
			<td style="width:192px;">Snaplock Industries, Salt Lake City UT</td>
			<td style="width:119px;"></td>
			<td style="width:163px;">Black</td>
		</tr>
		<tr height="52">
			<td height="52" style="height:52px;width:216px;">Wall Paint: Satin Premium Plus Internal Satin Enamel Custom Color Match</td>
			<td style="width:192px;">Behr, Inc Santa Ana CA</td>
			<td style="width:119px;">custom</td>
			<td style="width:163px;">Greyscale value = 45</td>
		</tr>
		<tr height="35">
			<td height="35" style="height:35px;width:216px;">Obstacle paint</td>
			<td style="width:192px;">Valspar Paints, Wheeling, IL</td>
			<td style="width:119px;">DuJour (#70002-6)</td>
			<td style="width:163px;">DuJour Greyscale value = 15</td>
		</tr>
		<tr height="35">
			<td height="35" style="height:35px;width:216px;">Obstacle paint</td>
			<td style="width:192px;">Valspar Paints, Wheeling, IL</td>
			<td style="width:119px;">Fired Earth (#6011-1)</td>
			<td style="width:163px;">Fired Earth Greyscale value = 95</td>
		</tr>
		<tr height="35">
			<td height="35" style="height:35px;width:216px;">Styrofoam obstacles</td>
			<td style="width:192px;">Universal Foam Products, Orlando CA</td>
			<td style="width:119px;">custom</td>
			<td style="width:163px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Con-Tact Brand Contact Paper</td>
			<td style="width:192px;">Lowe&#39;s Home Improvement</td>
			<td align="right" style="width:119px;">639982</td>
			<td style="width:163px;">Solid Black</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Con-Tact Brand Contact Paper</td>
			<td style="width:192px;">Lowe&#39;s Home Improvement</td>
			<td align="right" style="width:119px;">615542</td>
			<td style="width:163px;">Stainless Steel</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Con-Tact Brand Contact Paper</td>
			<td style="width:192px;">Lowe&#39;s Home Improvement</td>
			<td align="right" style="width:119px;">614416</td>
			<td style="width:163px;">Solid White</td>
		</tr>
		<tr height="52">
			<td height="52" style="height:52px;width:216px;">3 ft x 6 ft Standard tuff Olefin Floor Mat</td>
			<td style="width:192px;">Commercial Mats and Rubber A Division of Georgia Mills Direct Saratoga Springs, NY</td>
			<td style="width:119px;"></td>
			<td style="width:163px;">Charcoal</td>
		</tr>
		<tr height="52">
			<td height="52" style="height:52px;width:216px;">3 ft x 6 ft Standard tuff Olefin Floor Mat</td>
			<td style="width:192px;">Commercial Mats and Rubber A Division of Georgia Mills Direct Saratoga Springs, NY</td>
			<td style="width:119px;"></td>
			<td style="width:163px;">Smoke</td>
		</tr>
		<tr height="35">
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a standardized obstacle course for assessment of visual function in ultra low vision and artificial vision

We describe an indoor, portable, standardized course that can be used to evaluate obstacle avoidance in persons who have ultralow vision. Six sighted controls and 36 completely blind but otherwise healthy adult male (n=29) and female (n=13) subjects (age range 19-85 years), were enrolled in one of three studies involving testing of the BrainPort sensory substitution device. Subjects were asked to navigate the course prior to, and after, BrainPort training. They completed a total of 837 course runs in two different locations. Means and standard deviations were calculated across control types, courses, lights, and visits. We used a linear mixed effects model to compare different categories in the PPWS (percent preferred walking speed) and error percent data to show that the course iterations were properly designed. The course is relatively inexpensive, simple to administer, and has been shown to be a feasible way to test mobility function. Data analysis demonstrates that for the outcome of percent error as well as for percentage preferred walking speed, that each of the three courses is different, and that within each level, each of the three iterations are equal. This allows for randomization of the courses during administration.
Abbreviations: 
preferred walking speed (PWS) 
course speed (CS) 
percentage preferred walking speed (PPWS)

Subjects
Six sighted blindfolded, sighted, and 36 completely blind but otherwise healthy adult (age range 19-85 years), male (n=29) and female (n=13) subjects were enrolled in one of three studies involving testing of the BrainPort sensory substitution device (Wicab, Madison WI). All studies were approved by the University of Pittsburgh IRB and all subjects signed an approved informed consent document. All studies were a within subjects, repeated measures design such that each subject acted as th...

Watch this Scientific Journal Video about A Standardized Obstacle Course for Assessment of Visual Function in Ultra Low Vision and Artificial Vision at JoVE.com

A Standardized Obstacle Course for Assessment of Visual Function in Ultra Low Vision and Artificial Vision

We describe an indoor, portable, standardized course that can be used to evaluate obstacle avoidance in persons who have ultralow vision. The course is relatively inexpensive, simple to administer, and has been shown to be reliable and reproducible.

We describe an indoor, portable, standardized course that can be used to evaluate obstacle avoidance in persons who have ultralow vision. Six sighted ...

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