Long-term Characterization of Retinal Degeneration in Royal College of Surgeons Rats Using Spectral-Domain Optical Coherence TomographyRetinal Thickness in RCS Rats Acquired With OCT

摘要

Purpose:Prospectivetreatmentsforage-relatedmaculardegenerationandinheritedretinaldegenerationsarecommonlyevaluatedintheRoyalCollegeofSurgeons(RCS)ratbeforetranslationintoclinicalapplication.Historically,retinalthicknessobtainedthroughpostmortemanatomicassessmentshasbeenakeyoutcomemeasure;however,utilityofthismeasurementislimitedbecauseitprecludestheabilitytoperformlongitudinalstudies.Toovercomethislimitation,thepresentstudywasdesignedtoprovideabaselinelongitudinalquantificationofretinalthicknessintheRCSratbyusingspectral-domainopticalcoherencetomography(SD-OCT).Methods:HorizontalandverticallinearSD-OCTscanscenteredontheopticnervewerecapturedfromLong-EvanscontrolratsatP30,P60,P90andfromRCSratsbetweenP17andP90.Totalretina(TR),outernuclearlayer+(ONL+),innernuclearlayer(INL),andretinalpigmentepithelium(RPE)thicknesseswerequantified.HistologicsectionsofRCSretinaobtainedfromP21toP60werecomparedtoSD-OCTimages.Results:InRCSrats,TRandONL+thicknessdecreasedsignificantlyascomparedtoLong-Evanscontrols.ChangesinINLandRPEthicknesswerenotsignificantlydifferentbetweencontrolandRCSretinas.FromP30toP90asubretinalhyperreflectivelayer(HRL)wasobservedandquantifiedinRCSrats.Aftercorrelationwithhistology,theHRLwasidentifiedasdisorganizedoutersegmentsandthelocationofaccumulateddebris.Conclusions:RetinallayerthicknesscanbequantifiedlongitudinallythroughoutthecourseofretinaldegenerationintheRCSratbyusingSD-OCT.ThicknessmeasurementsobtainedwithSD-OCTwereconsistentwithpreviousanatomicthicknessassessments.ThisstudyprovidesbaselinedataforfuturelongitudinalassessmentoftherapeuticagentsintheRCSrat.