3/16/16. Anatomy Diagnos:cs Nuclear Sclerosis Cataracts Cataract Surgery Lens Subluxa:on Anterior Lens Luxa:on Posterior Lens Luxa:on

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1 Board Cer:fied Veterinary Ophthalmologist The Animal Eye Ins:tute Anatomy Diagnos:cs Nuclear Sclerosis Cataracts Cataract Surgery Lens Subluxa:on Anterior Lens Luxa:on Posterior Lens Luxa:on Iris Cornea Ciliary Processes Zonules Lens Posterior Epithelium Anterior Chamber Iridocorneal Angle Tapetum Op:c Nerve Vitreous Re:na Choroid Anterior Epithelium Nucleus Cortex Equator Ciliary Body Sclera 1

2 If a pa:ent has any concern for len:cular disease, you should be obtaining intraocular pressures Normal agerelated change in dogs Seen in dogs 6 years of age and older The nucleus becomes more dense, but does not restrict vision The dog should not be experiencing vision problems The veterinarian should be able to obtain a clear fundus examina:on This is NOT a cataract 2

3 Incipient (<10%) Early Immature (1150%) Late Immature (5199%) Mature (100%) Hypermature Morgagnian Inherited Diabetes Mellitus Senile Radia:on Nutri:onal (Hypocalcemia) Progressive Re:nal Atrophy Lens Luxa:on Uvei:s Electrocu:on Drugs/Toxins (Ketoconazole) Trauma 3

4 83% func:onally visual at the end of the study 10% blind 7% decreased vision Complica:ons: PostOpera:ve Ocular Hypertension Corneal Lipid Uvei:s Intraocular Hemorrhage Re:nal Detachment Glaucoma Boston Terriers have a higher complica:on rate 90% success rate Complica:ons: Posterior Capsule Opacifica:on Re:nal Detachment (12%) Glaucoma (<10%) Prevalence of failure was less than 10% at 3 year follow up Boston Terriers, Cocker Spaniels, CockerPoodle, Shih Tzus at a more increased risk of glaucoma Hypermature cataracts increased the complica:on rate (refer earlier!) Failure of nontreated eyes compared to medically managed eyes: 65 :mes higher in nontreated eyes Failure of nontreated eyes compared to surgically managed eyes: 255 :mes higher in nontreated eyes Failure of medically managed eyes compared to surgically managed eyes: 4 :mes higher in medically managed eyes Mature and hypermature cataracts had a higher failure rate (refer earlier!) Failure: Glaucoma, severe corneal disease, hyphema, uvei:s Complete Blood Count Biochemical Profile Urinalysis Urine Culture (if diabe:c) 4

5 16:07:47 18:06:38 3/16/16 Electrore:nogram To cut or not to cut Normal? Progressive Re:nal Atrophy? Sudden Acquired Re:nal Degenera:on Syndrome? RGI O.S. RetinoGraphics, Inc. 9 Dock Road, Norwalk, CT Owner: Haeussler Patient: Vegas Breed: Boxer Age (mo): 8 I.D.: 13 10µV/Div. Smoothed (4) 1 2 5ms/Div. Filter: None Flash: Single 0dB White LED CURSORS 1 2 <21> 3 4 <43> Implicit Time (ms): Amplitude (µv): COMMENTS: Presumed Normal DARKADAPT 15m Test: ERG Date: Sep Ave. 0 of 4 ITT: 2s RGI Owner: Gayheart Breed: 10µV/Div. Smoothed (4) O.D. 1 2 CURSORS Implicit Time (ms): Amplitude (µv): COMMENTS: RetinoGraphics, Inc. 9 Dock Road, Norwalk, CT Patient: Emma Age (mo): 144 I.D.: 5ms/Div. Filter: None Flash: Single 0dB White LED Test: ERG Date: Jan Ave. of <21> 3 4 <43> DARKADAPT 15m ITT: 2s Ultrasound Size of Lens Re:nal Detachment Capsule Rupture Vitreal Consolida:on Intraocular Tumor 3mm incision made at the limbus Anterior chamber replaced with viscoelas:c Anterior capsulotomy and capsulectomy performed Lens removed via phacoemulsifica:on Lens epithelial cells removed from the capsule via irriga:on and aspira:on IOL inserted into the capsule Incision closed with 90 Vicryl 5

6 Topical an:bio:cs (Ofloxacin) Oral an:bio:cs (Clavamox) Topical NSAIDs (Flurbiprofen or Diclofenac) Oral NSAIDs (Carprofen) Topical Lubricant (Op:xcare) Protec:ve Ecollar Restricted Ac:vity Recheck in 2 weeks Reduc:on of medica:ons over :me Lifelong follow up and medica:ons Low fat diets and low fat treats for diabe:cs The sooner, the beier outcome Allowing the lens to mature, or ripen is no longer appropriate Diabe:cs especially need to be referred quickly to the risk of lens capsule rupture, re:nal detachment, glaucoma, and uvei:s Diabe:c Schnauzers need to be referred very quickly due to the risk of lens capsule rupture Place each pa:ent with cataracts on topical flurbiprofen or diclofenac (topical NSAIDs) once or twice daily 6

7 Many products on the market Many are proprietary blends of unlisted ingredients Neutraceu:cals are completely unregulated and most NOT BACKED BY RESEARCH Reports from Russia in 2000s indicated a therapeu:c effect of N acetylcarnosine on cataracts Possible benefits have been seen in vitro Can disaggregate crystallins aggregated by glyca:on Reduces inac:va:on of enzymes by glyca:on Has an:oxidant and oxygen freeradical scavenging ac:vi:s Inhibits nonenzyma:c glycosyla:on and crosslinking of proteins induced by reac:ve aldehydes Inhibits forma:on of MDAinduced proteinassociated advanced glycosyla:on end products Evalua:on of lens opacity via digital image processing ~2% improvement in lens opacity 75% of owners reported improved vision No clinical evalua:on of lens opacity No placebo Unmasked 7

8 Do they work? There may be some minimal effect of reversing early changes to crystallins in the lens Cannot undo lens density changes Cannot undo lens fiber disorganiza:on Cannot undo cellular lysis Any benefit of these types of drops would be limited to senile cataracts Cost:Benefit? $50$100 per boile Many causes of lens subluxa:ons: Congenital Primary Inherited (between 36 years of age) Secondary Glaucoma Uvei:s Trauma Inherited in Jack Russell Terriers Due to a muta:on in the HSF4 gene Other breeds founds to have inherited primary lens luxa:on Sealyham Wirehaired Fox Mini Bull Terrier Terrier crosses Tibetan Terrier Shar Pei 8

9 Ideal management of lens subluxa:ons is surgical removal of the lens with or without IOL placement Alterna:vely, a mio:c can be used if the lens is posteriorly subluxated Latanoprost Demecarium Bromide At 46 weeks and 3 months post diagnosis of lens instability, 100% of dogs retained vision At 1 year post diagnosis, 80% retained vision At 2 years post diagnosis 11/19 (58%) retained vision è è? Primary lens luxa:on in the dog Occurs as a hereditary defect in collagen composi:on of the lens zonules Anterior lens luxa:on may present from mild to severe discomfort, conjunc:val hyperemia, slight cloudiness to the eye Anterior lens luxa:on cons:tutes an emergency as a rapid rise in intraocular pressure can result in permanent blindness 9

10 Treatment Lens extrac:on via intracapsular lens extrac:on 160 degree corneal incision Vitreal aiachments severed Par:al vitrectomy performed Large incision increases risk of infec:on Ongoing risk of re:nal detachment due to vitreal degenera:on Risk of glaucoma Aphakic (see distance items, struggle with nearfield vision What can you do? Start pa:ent on dorzolamide or dorzolamide:molol TID if intraocular pressures are greater than 25mmHg DO NOT GIVE ANY MIOTICS! Latanoprost Demecarium Bromide Pilocarpine Flurbiprofen SID to decrease subclinical uvei:s caused by the lens bumping into intraocular structures Refer immediately What else can be done? Is the pa:ent visual? Does the pa:ent have a dazzle response? If pa:ent is painful, has increased intraocular pressures, no menace, no dazzle, and referral is not an op:on: Enuclea:on Mannitol, couch the lens, mio:c (latanoprost) If nothing is done, the intraocular pressures are normal, and the lens remains anteriorly luxated, endothelial decompensa:on can occur. This can result in corneal rupture 10

11 Difficult to remove surgically High risk of re:na detachment if the lens is removed or if the lens stays in the vitreous High risk of glaucoma if the lens migrates anteriorly If the lens is posteriorly luxated, prescribe a topical mio:c (latanoprost) to trap the lens into the posterior segment $ Photos Descrip:ons Index Categorized Call us: Amazon.com 11