cataracts in rabbits - the unusual pet vets · cataracts in rabbits what is a cataract? a cataract...

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CATARACTSINRABBITSWhatisacataract?

Acataractappearsasaslightlyhazytowhiteopacitywithinthepupiloftheeye.Thisiscausedbyachangeinthenatureofthelensoftheeye.Thelenscanoftenappear'crystallized'oncloseinspection.Astheyprogresscataractscausealossofvision,whichmaybegradualorsuddeninonset.Itcanoccuratanyageandoneorbotheyescanbeaffectedsimultaneously.

Whatcancausecataractsinrabbits?

Themaincauseofcataractsinrabbitsisin-utero(priortobirth)infectionofEncephalitozooncuniculi(EC),thisisusuallytransmittedfromthemothertobaby.Thisisasinglecellorganismthataffectsareport70-80%ofrabbitsinAustralia.SerologytestingforthepresenceofECantibodiesinarabbitwithcataractscantellusiftheyhaveeverbeenexposedtothisparasite.

Inotheranimalsdiabetesisamajorcauseofcataracts.Diabetesinrabbitsisrare,howeveritcanbediagnosedwithbloodtests.

Howdowetreatcataracts?

Currentlynorealmedicalcureforcataracts.Cataractsurgery,whichisperformedbyaveterinaryeyespecialist,isthebesttreatment.Thespecialistswill,underanestheticremovethechangedlensandallowsighttoreturntotheaffectedeye.Moreimportantlyitpreventsglaucomaanduveitis(otherproblemsthatcanaffecttheeye).

Iftherabbithasbeenexposedto,ortestspositivetoECthenthereisanoralmedicationthatwillbestartedtotreatthis.

Whatelsecouldthelenschangesbe?

Themainalternativediagnosistocataractsisnuclearsclerosis.Thisisanoldagechangethatoccursslowlyandisamildgrey/bluecolorationtothelens.Nuclearsclerosisdoesnotgenerallycauseaverywhitepupil.Aveterinaryeyespecialistcanconfirmchangestothelensarenuclearsclerosisormildimmaturecataract.

WhatcanhappenifIdonottreatthecataracts?

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Therearetwomajorproblemswhichcanoccurinuntreatedcataracts,onaveragetheseoccurin60%ofrabbitsdiagnosedwithcataracts.

Lensluxation-Asthelensisnotasflexibleafterformingacataractitcanbreakthefineattachmentsthatholditinplace.ThisLenscanthenfloatfreeandblockthedrainageoftheeyeball.Theeyeballitselfthenincreasesinsize.Thisconditioniscalledglaucomaandisoftenuntreatableinrabbits.Itisanextremelypainfulconditionandinsomecasesrequiresremovaloftheeye.

Uveitits-Thechangedlenscanruptureleakinglenstissueintotheeye.Thiscausesaseverereactionandtheentireeyebecomesinflamed.Thisconditionisalsoverypainfulanduncomfortableforyourrabbitandoftenrequireseyeremoval.

CanIpreventmyrabbitfromgettingcataracts?CanIpreventtheothereyefromformingacataract?

Thereisnothingwecandotopreventcataractsinrabbits.InfectionwithECinrabbitsisverycommonbutnotallrabbitsdevelopcataractsfromit.Onceoneeyeisaffectedthereisastrongpossibilitythattheothereyewillalsobeaffected.

Howquicklydocataractsdevelop?

Thereisnoaverageprogressionofcataracts.Theycanstaymildandimmature(greytohazypupil)foryearsortheycansuddenlyprogresstoseverematurecataracts(white)inamatterofdays.

Willcataractsreoccuraftersurgery?

No,cataractsareachangeinthelensandduringsurgerythelensisremovedallowingvisiontoreturn.

WhatelsecanECcause?Andcanthisaffectsurgery?

EChasalsobeenassociatedwithheadtilts(vestibulardisease)andrenal(kidney)disease.TheseconditionsdonotoccurineveryrabbitinfectedwithEC.Itisreportedthatupto80%ofrabbitsinAustraliacanbeinfectedwithEC.Ifsurgeryisbeingconsidereditmaybeworthwhiletoruleoutrenaldiseasewithbloodtests.Ifrenaldiseaseispresentitcanaffecttheanestheticrequiredforthesurgery.

Ifyouhaveanyquestionsorareatallworriedaboutyourrabbitpleasedon’thesitatetogetintouchwithus.