Althoughcerebralvisualimpairment(CVI)istheleadingcauseoflowvisioninchildren,itisdifficulttodiagnose becauseaffectedchildrenoftenlacktheverbalandcognitiveskillsnecessarytoparticipateinstandard diagnosticprocedures.Diagnostictestsexistthatworkaroundtheneedforeffectivecommunication,butthey areeithersubjectiveorimpracticaltoadminister.Asaresult,CVIislikelyunderdiagnosed,andsincethereis noeffectivetreatment,mostpatientsfacealifetimeofdisability.Thisresearchprojectwillevaluatetheutilityof OptokineSys,anoveltoolwedevelopedformeasuringvisualfunctioninbraininjuredchildren.Thesystem automaticallydetectssmoothtrackingeyemovementsusing3mainelements:acomputerdisplayfor presentingvisualstimuli,adesktopeyetrackingdevice,andacomputeralgorithmtodeterminewhetherthe eyesaremovinginsynchronywiththevisualstimulus.Thesystemusesanautomatedprocedureto systematicallyadjustthespatialfrequency(finenessofdetail)orcontrast(lighttodarkratio),themost widelyusedmeasuresofspatialvisualfunction.Thesystemautomaticallyseeksthethresholdsetting?i.e.the mostchallengingstimulusatwhichthesubjectcontinuestotrack.Thesystemalsokeepschildrenengagedin thetaskbyprovidingrealtimerewardintheformofmusicthatisplayedonlywhentheyfollowthestimulus.
SpecificAim1 willcomparemeasuresmadewithOptokineSysagainststandardmeasuresofvision,inchildren withbraininjurywhocannonethelesscommunicate.OptokineSysmeasuresinthispopulationare hypothesizedtoretaincertaincharacteristicpropertiescomparedwithpsychophysicalmeasuresofspatial discriminationandcontrastsensitivity.Specifically,thiswillshowtheextenttowhichthenewsystems?results reflectvariationinthetargetpopulation?sspatialvisualfunction,asdesired,orareratherdominatedbyits variationinotherfunctionssuchasattentionandeyemovement.
SpecificAim2 willevaluatethereliabilityof OptokineSysinchildrenwhosebraininjuriespreventthemfromparticipatinginstandardvisualassessments. Forbothspatialfrequencyandcontrast,thresholdswillbetestedtwiceononedayandtwiceonthe subsequentday.Themainoutcomeisthetestretestreliability,asmeasuredbyvariability.Thevariabilityis hypothesizedtobehigherbetweendaysthanonthesameday,inkeepingwiththewaxingandwaningnature ofbrainfunctionfollowinginjury.Theseexperimentswilldeterminetheutilityofautomatedvision measurementsinanunderservedpopulationthatposesparticulardiagnosticchallenges.Thecurrentstudywill thuswilllaythegroundworkforfutureclinicaltrialsofOptokineSysasatoolforassessingthenaturalhistoryof CVIinchildrenwithbraininjury.Inaddition,thesystemcouldbeusedtotrainvisualperception,anapproach thathasalreadyprovedeffectiveinrodentstudies.Together,thenewsystemhasthepotentialtofillthegapin ourunderstandingofthecourseofCVIafterbraininjury,andtoprovidetoolsforchangingthatcourse.
Theproposedresearchisrelevanttopublichealthbecauseitwilldevelopmethodsofassessing,andpossibly treating, visual impairment resulting from brain injury. It has the potential to improve clinical outcomes for millionsofpeople,particularlychildren,whoseabilitytofunctioninsocietyisseverelylimitedbybraininjury. TheprojectisrelevanttotheNIH?smissionbecauseitaimstocreatetoolstoovercomebarrierstoassessment andtreatment(suchascomorbidcognitiveandcommunicationdeficits)thatcurrentlymakevisualimpairment difficulttoquantify,diagnose,andtreat.
Mooney, Scott W J; Hill, N Jeremy; Tuzun, Melis S et al. (2018) Curveball: A tool for rapid measurement of contrast sensitivity based on smooth eye movements. J Vis 18:7 |
Suner, Melis; Prusky, Glen T; Carmel, Jason B et al. (2017) Longitudinal Quantification of Eye-Movement Impairments after Pontine Hemorrhage. Front Neurol 8:165 |