ophtho

  1. anophthlamos
    • absense of the eye
    • seen in pigs with vitamin A deficiency
  2. nanophthalmos
    • normal eye but small
    • seen in pigs with vitamin A deficiency
  3. microphthalmos
    • a small eye with abnormalities
    • seen in pigs with vitamin A deficiency
  4. enucleation
    • removal of the whole globe
    • within periorbita
  5. externation
    • removal of the contents of the orbit
    • most common
    • external to periorbita
  6. evisceration
    • removal of the contents of the globe
    • put in prosthetic - can be done with heathy cornea.
  7. indications to enucleate
    • blind and painful (glaucoma or uveitis that O can't treat)
    • severly damaged eye with loss of contents or high risk of infection
    • intraocular neoplasia
    • Carefully close periorbita CT to prevent sinking, or can use bowler hat prosthetic (NOT in neoplasia or infection)
  8. what is special about bovine enucleations?
    • very thin bony shelf on floor of orbit
    • Very thin medial wall in MANY species
    • bones are paper-thin, and can cause emphysema or infection!!
  9. orbit
    • cavity in the skull containing the eye, supporting structures and other important structures
    • floor is incomplete, "open" to the oral cavity in most species (cows have paper thin floor)
    • Diseases nearby (sinus or teeth) can manifest in orbit
    • full of the periorbita
    • temporalis and masseter are walls.  If they atrophy eye sinks.  if they hypertrophy, exophthalmos.  
    • Dehydration or starvation collapse fat pad, enophthalmos
    • ramus of mandible right behind eye, so inflammation of orbit, hurts to open the mouth!  And mandibular tumor could push on eye
  10. vessels near orbit
    maxillary artery and deep facial vein run along orbit, don't cut them!!
  11. rule-outs for exophthalmos (5)
    • proptosis (this IS exophthalmos)
    • CHANG (space-occupying lesions - cyst, hematoma, abscess, neoplasia, granuloma
    • myositis/myopathy (acute) of masticatory muscles
    • emphysema
    • GLAUCOMA/BUPHTHALMOS (cow-eyed, enlarged) !!
  12. rule-outs for enophthalmos (10)
    • ocular pain (suck back when hurts)
    • dehydration (fat)
    • emaciation (fat)
    • myositis/myopathy (chronic, atrophy)
    • trauma
    • Horner's (usu other signs, symp fibers in periorbita keep constricted)
    • neoplasia in anterior orbit
    • zygomatic mucocoele in anterior orbit
    • emphysema
    • SMALL GLOBE (rupture, microphthalmos, phthisis bulbi)
  13. orbital cellulitis/abscess
    • EMERGENCY
    • peracute to acute, rapid progression, sick and painful, exophthalmos, lid and periorbital swelling, red eye (chemosis, hyperemia), abnormal d/c, pain opening mouth
    • no particular signalment
    • don't differentiate cellulitis vs abscess, tx is same! idiopathic in dogs/cats, trauma (recent or old), extension from sinuses, FB (oral cavity, conjunctival or facial), tooth root abscess or recent dental in brachycephalic dogs and cats
    • abx +/- tarsorrhaphy (sew eyelids together to protect), NSAIDs, analgesics, soft food, hot packs
  14. orbit neoplasia
    • primary in orbit, metastatic or an extension from other tissues
    • 90+% malignant, adenocarcinoma most common
    • usu older animals, progressive changes
    • minimal to no pain at early (unless VERY fast)
    • unilateral
    • sx extirpation, enucleation or exteneration, chemo, radiation (?)
    • usu poor px because disease ADVANCED before we find it--lots of space behind the eye
  15. Masticatory Muscle Myositis (MMM)
    • UNCOMMON but happens in SA
    • HUGELY important to dx and tx early.  
    • no retropulsion, exophthalmos, prolapse, cheek, temporalis swollen and painful
    • autoimmune inflammatory disease of muscles innervated by mandibular nerve (masseter, temporalis, pterygoids, rostral digastricus).  
    • Post-vax or infection?  aka atrophic myositis
    • usu large breed dogs (only dogs), 3 years (<1 in CKCS)
    • swelling/pain of those muscles, can't open mouth or pain (jaw hang open?), SOME have eye signs (usu bilateral exophthalmos, nictitans protrusion, periorbital/lid edema, conjunctival and episcleral vascular engorgement, blindness?, hypersalivation?  reluctant to eat or drink, clinical signs 2-3 weeks, recurrs frequently
    • chronic: atrophy of muscles, can't open mouth/trismus, enopthalmos with entropion, nictitans prolapse, other immune diseases?
    • run circulating ab test and/or ELISA (both) or biopsy temporalis or masseter - make sure you're deep
    • ON EXAM
    • TX: steroids, immune-modulatory if can't use steroids, PT and supportive, monitor for relapse.  DO NOT rip jaw open under anesthesia!
  16. orbital mucocoele
    • no signalment, etiology unknown, slow or fast onset, minimal pain, signs vary with position.  
    • swelling of orbit, exophthalmos or enophthalmos or deviated globe, nictitans protrusion, ventral or temporal fornix swollen and lobulated cyst visible
    • aspirate - thick!  
    • tx with abx, but usu need sx to remove gland (zygomatic)
  17. orbital fractures
    • common in horses
    • acute, pain, orbital swelling, chemosis (conj edema), exo or enophthalmos, SQ and conjunctival emphysema, bony irregularities, crepitus, epistaxis
    • simple fractures that aren't displaced can avoid sx.  Abx, tx ocular PRN, TETANUS in equine, emphysema common (resolves slowly)
  18. extraocular myositis (EOM)
    • RARE
    • hugely popping out bilateral eyeballs!  unmissable presentation - increased scleral exposure, exotropia (lateral strabismus), epiphora (tearing), conjunctivitis.  NOT PAINFUL, seem happy.  Esp goldens, intact females, <3yo
    • tx with steroids
  19. 4 layers of eyelids
    • skin
    • muscle: orbicularis oculi (ring around eye), levator palpebrae superioris (pulls eyelid up)
    • tarsus/tarsal plate: CT surrounding tarsal glands, MUST close this layer in repair!
    • palpebral conjunctiva
    • medial and lateral canthal ligaments on the corners
  20. nictitans
    • T-shaped cartilage with harderian gland, aqueous.
    • prolapses with Horners (cows - ipsilateral dry nose, horses sweat), may have red eye from loss of vasoconstriction
    • palpebral and bulbar surfaces covered with conjunctiva
  21. tear film
    • tri-layered
    • lipid on top - tarsal glands, prevent evaporation
    • aqueous (largest) - lacrimal glands, nutrients and waste
    • mucin on bottom - conjunctival goblet cells, adhere to corneal surface
  22. conjunctiva
    • stratified squamous to stratified columnar epithelial mucous membrane with LOTS of goblet cells, esp in fornices
    • subdivisions: palpebral (inside of eyelids) vs bulbar (outside of the globe to limbus).
    • transitions to cornea at the LIMBUS
    • conjunctival sac is the potential space inside closed lids
  23. layers of the globe (3)
    • outer: fibrous = sclera + cornea, lamina cribrosa for ocular nerve to exit (sieve). Sclera continuous with dura mater around optic nerve
    • middle: vascular = iris, ciliary body, choroid (continuous with pia mater around optic nerve)
    • inner: neural = retina (formed by optic cup)
  24. cornea
    • 4 layers plus tear film.  
    • 1. epithelial (+ basement membrane, hydrophobic), 2. stroma, biggest (hydrophilic). 3. descemet's membrane (hydrophobic). 4. posterior epithelium or endothelium (hydrophobic, pumps to maintain dehydration of stroma)
    • transparent due to avascular, non-keratinized, no pigment, well organized uniform collagen, dehydration.  STRUCTURE + DEHYDRATION = CLARITY
  25. uvea/vascular tunic
    • can visualize iris and choroid (through pupil), can't visualize ciliary body
    • anterior uveal tract is iris and ciliary body
    • anterior uveitis is inflammation of iris and ciliary body
  26. iris
    • stroma is collagen and cells with only posterior epithelium, which continues over ciliary process and is contiguous with sensory retina and retina pigmented epithelium.  
    • Has sphincter (pupil margin) and dilator (sun spokes) muscles (neuroectoderm from epithelial layer).  
    • Color and shape varies
    • anterior uvea, vascular tunic
  27. ciliary body
    • anterior uvea, vascular tunic
    • two cell layers of retina and uveal tissue (muscles, vessels)
    • iris posterior epithelium continues over ciliary body and blends into sensory retina and retinal epithelium
    • functions: 1. neuroepithelial cells make aqueous humor.  2. muscles control aqueous humor outflow (drainage angle).  3. accomodation via muscles, near and far vision caused by changing tension on zonules/zonular ligaments
    • (egg yolk in mushroom cap)
  28. aqueous humor
    made by ciliary body neuroepithelial cells, flows through posterior chamber across lens and out pupil into anterior chamber, around chamber and out through trabecular meshwrok of iridocorneal/filtration angle (circumferentially deep to limbus at edges of anterior iris, not just sagittal!)
  29. choroid
    • posterior uvea/vascular tunic
    • between sclera and retina
    • tapetum is part of choroid
    • vessels are orange-red and less regular and defined than retinal vessels
    • function: blood supply nourishes and removes waste from outer portion of retina, lymphatic drainage.
    • intrinsic nerve supply, secretory cells
    • continuous with pia-arachnoid mater around optic nerve
  30. lens
    capsule on outside is basement membrane of lens epithelial cells.  Anterior capsule thicker than posterior (with age) because anterior epithelium keeps dividing and migrating to equator (nuclear sclerosis - lens hardens and can't accomodate).  Posterior epithelial cells go away after development.
  31. retinal tunic and 3 parts
    • develops from optic cup
    • POR - pars optica retinae (sensory)
    • PIR - pars iridica retinae (non-sensory, part of iris epithelium that is continuous)
    • PCR - pars ciliaris retinae (non-sensory, part of ciliary epithelium that is continuous)
    • pigmented epithelium lines outside and down the inside of the nerve
    • 10 layers, Pigmented epithelium closest to sclera, 9 layers of photoreceptors including rods and cones between that and vitreous
  32. optic nerve
    • cranial nerve 2
    • axons of retinal ganglia converge at optic disc, myelinate, exit through lamina cribosa in sclera.  Covered by meninges, pas through periorbita, though optic foramen.  Head (disc) visible in eye exam
  33. fundic exam
    • examining structures in back of eye (wall of the organ opposite the opening). 
    • optic nerve, retina, choroid, tapetum, retinal vessels
  34. eyelid functions (5)
    • protect the globe and other structures
    • sweep particles from ocular surface
    • restrict tear film overflow from eye
    • precorneal tear film (produce some of tear film, there are MANY glands in the eyelids)
    • Lacrimal pump to assist drainage of the pre-corneal tear film
  35. puppies/altricial eyes open
    • medial to lateral
    • start at 8-9d, done by 2-3wk
    • premature - need lube!!!  No glands yet!!
    • delayed - gentle opening with cotton and saline, flush and clean, fluorescein, tx PRN
    • Neonatal ophthalmia (swollen eyes or lids pre-opening) is an EMERGENCY
  36. eyelid agenesis aka eyelid coloboma
    • born with no eyelid in some place!  Congenital but may present at any time including never
    • all species, more in some cat breeds
    • hair is rubbing on globe (trichiasis) so usu need Rx.  Can cryo the hairs or lip-to-lid transposition (in cats, not horses)
  37. dermoids
    • choristomas (normal skin in abnormal place)
    • any species
    • any ocular surface - lid, nictitans, cornea, lacrimating caruncle
    • remove b/c irritating
    • may not have visible hairs for months, often mean lid can't close properly, damage rest of eye.
    • GOOD exam - what if it's full thickness?
  38. trichiasis
    • normal hairs touching ocular surface
    • misdirected lashes vs normal facial hairs from entropion or nasal fold, etc.
  39. distichiasis
    • supernumerary cilia arising from tarsal or other gland openings to rub on the eye
    • MOST COMMON
    • normal hair growing from abnormal place.  
    • Not all animals symptomatic, don't even need to tell O
  40. ectopic cilia or hairs
    • hairs growing through palpebral conjunctiva and touching cornea or conjunctiva
    • common in Shih tzu, Lhasa, dogs
    • VERY irritating, severe disease quickly!!.  VERY hard to find sometimes.
    • May be able to see dark spots, but take a while to erupt so present in middle age?  Warn O.
  41. treatment of hairs that touch the eyeball
    • microcryoepilation: preferred! may cause eyelid depigmentation, possibly transient. Could also necrose so only a little area!
    • Epilation/plucking: just one?  Clients may be able to do themselves.  No really advised. 
    • Electroepilation: needle, current, smoke.  More than a few - scar!!
    • excise: ectopic or single hairs only!  Biopsy punch
    • divert offending hairs: turn lid margin away from cornea (entropion sx)
    • DO NOT CUT LID MARGINS
    • May want to refer.
  42. euryblepharon
    • abnormally large palpebral fissure but otherwise normal lids and globe.  Lots of "scleral show".  Desirable in some breeds (St. Bernard, Bloodhound, Clumber spaniel), worrysome in brachycephalics
    • tx: medial canthoplasty +/- lateral canthoplasty.  REFER
  43. Entropion
    • rolling in or inward tilt of the eyelid margin toward cornea.  Okay as long as hairs don't CONTACT--it is never okay for hairs to rub the cornea
    • congenital (most common in d/c) vs spastic (excessive squint due to ocular pain, self-perpetuating) vs cicatricial (scarring) vs secondary to enophthalmos.  
    • Can therefore be primary or secondary (dehydrated, sick, stressed neonate foals, goats, lambs
    • signs: epiphora, mucus, blepharospasm, conjunctivitis, corneal disease in adjacent cornea, self-trauma, ROLLING IN OF LID MARGIN (NEVER NORMAL)
    • examine before and after anesthestic to reduce spastic so you don't remove too much/over-correct.  
    • Sx: incise just where hairs start to grow, parallel lid margin length of entropion, roll eyelid out and take as much out ("tuck) as rolled. Take a slip of muscle too and closure is nicer. Suture in middle, and keep suturing middles until closed.  Can just tack if you think it's temporary, esp in LA. Wound clips! or SQ "bleb" next to eye (procaine penicillin), everts lid for 2-3 days
  44. extropion
    • congential vs cicatricial (scarring) vs transient seen in large dogs.
    • signs: turned out lid, red eye, conjunctivitis
    • tx: refer!  Not crucial, hairs not rubbing eye
  45. most common eyelid tumors in dog(4), cat (2), horse (3), cow (1)
    • dog: sebaceous adenoma, papilloma, histiocytoma, melanoma
    • cat: squamous cell carcinoma, fibrosarcoma
    • horse: squamous cell carcinoma, sarcoid, melanoma
    • cow: squamous cell carcinoma
  46. sebaceous adenoma
    • most common eyelid tumor in middle aged to older dogs
    • looks like a papilloma or wart
    • may cause eyelid inflammation if gland ruptures into tissues.
    • Usually benign (usually more visible between head and tail)
  47. squamous cell carcinoma
    • most common ocular tumor in horse, cow, (cat)
    • variable presentation
  48. sarcoid
    • most common skin tumor in horses
    • variable presentation
  49. eyelid tumor treatment
    • NEED histo to diagnose (but careful with needles near the eye!)
    • remove ASAP in horse, cow, cat (usu benign in dogs).  Also if looks inflamed or causing eye disease/inflame.  
    • REMOVE BEFORE >1/4 lid length (refer after)
    • assess regional lymph nodes--go on a tumor hunt before sx to get px
  50. removal of eyelid masses
    • simple excision, "V" or parallel lines with a "V" at the bottom (for larger, don't give eyelid away)
    • close tarsal plate and skin using 5-0 or 6-0 vicryl.   NEVER CLOSE CONJUNCTIVA (suture rubs cornea
    • Use buried figure 8 suture in tarsal plate to keep knot away from lid margin and conjunctiva.
    • eyelid wounds bleed profusely but also heal really well
    • just make sure you close the tarsal plate, and don't give away eyelid or skin if you can help it.
  51. Things that cause nictitans prolapse (7)
    • Horner's
    • space-occupying mass in orbit
    • ANY condition causing enophthalmos (PAIN)
    • phthisis bulbi or microphthalmos
    • Idiopathic protrusion ("Haws" in cats?)
    • Neoplasia of gland of nictitans
    • TETANUS (spasmodic prolapse due to spasmodic globe retraction)
  52. diseases of nictitans (6)
    • Scrolling of cartilage: deformed tips of crossbar (refer)
    • trauma: fine if small, refer if large (repair causes corneal ulcers)
    • Inflammatory diseases: any conjunctival can cause, "atypically pannus", habronema in horses, granulomatous diseases in dogs
    • neoplasia: SCC esp in LA, adenocarcinoma of gland, lymphoma
    • follicular conjunctivitis: self limiting and cosmetic, increased mucoid d/c esp after swimming, look for follicle hypertrophy on everted nictitans, "puff"
    • cherry eye: prolapse of gland, esp in dogs.  Refer large breeds and recurrent (cartilage deformity usu)
    • Repair via Morgan Pocket Technique: incise on each side, make a pocket and leave holes on either end for drainage, make sure sutures don't rub cornea)
  53. foreign bodies and the nictitans
    • it gets them. A lot.
    • bulbar surface needs to be examined in every species with adjacent ulcer or delayed healing.
    • ESP HORSE - they have a pocket on the bulbar surface
    • Don't grab ON edge, just near
    • a circular ulcer = infection because that's how bacteria grow
  54. eyelid tumors in cats
    ARE BAD
  55. the journey of tears (lacrimal system)
    • lacrimal gland, gland of the 3rd eyelid (conjunctival goblet cells, tarsal glands)
    • lacrimal puncta
    • canaliculus
    • lacrimal sac
    • nasolacrimal duct
    • drain out the nose
  56. functions of the tear film (5)
    • keeps corneal surface smooth and moist for comfort, clarity, transparency
    • delivers nutrients to cornea and remove metabolites
    • flushes debris and mucus from eye
    • lubrication for smooth lid movement
    • many other functions (immunoglobulins, enzymes, transport)
  57. secretory diseases: quantitative vs qualitative
    • quantitative: decreased aqueous layer shown by schirmer tear test = KCS
    • qualititative: decreased mucin and/or lipid, aqueous can't do its job
  58. LFU
    • lacrimal gland
    • ocular surface
    • interconnecting innervation
    • three portions inter-relate to control tear secretion and ALL are critical for ocular health
    • assess quantity of tears, quality of tears (adhesion or evaporation) and assess related nerves (corneal sensation, assess lacrimal function)
  59. mucin and lipid deficiencies in tear film
    • abnormal QUALITY of tear film due to poor adhesion or evaporation
    • signs of dry eye in the face of a normal Schirmer - hard to dx.  Dx via tear film break up time (TFBUT) and tear analysis
    • caused by chronic conjunctivitis, blepharitis.  Congenital?  Omega 3?
  60. every uncomfortable eye needs (3)
    • schirmer
    • fluorescene
    • intra-ocular pressure
  61. keratoconjunctivitis sicca (KCS)
    def
    species
    signs
    lesions
    dx
    tx
    • reduced quantity of tears as seen by schirmer tear test.  One of most common SA ocular dzs. Chronic degenerative disease of cornea/conjunctiva, causes discomfort
    • usu dogs, sometimes cats and horses (esp Burmese cats). rare in other species. 
    • signs: discomfort, discharge (mucoid to mucopurulent).  CLASSIC: adherent filaments of mucus stuck to cornea, conjunctiva, lid.  Hard to remove. 
    • can cause keratitis (haze, clouding, neovascularization, pigmentation  of cornea), corneal ulcers.  Neurogenic are accompanied by ipsilateral dry planum nasale, nostril and nasal passage (xeromycteria - dry nasal mucosa)
    • Ear exams, esp for neurogenic, corneoconjunctival cytology and culture.  STT and fluroscein (watch for ulcers, can't heal!), cytology, culture
    • Horses with KCS - endoscopy, skull rads, CT/MRI, thyroid assessment
    • tx: correct inciting cause, tear replacement, increase tear production via immune moderation cyclosporine 0.2%, then 2%, then tacrolimus, MAYBE parasympathomimetics (pilocarpine, used in horses b/c their KCS usu neurogenic), control infection with abx, inflammation with NSAIDs or maybe steroids, eliminate mucus with acetylcysteine PRN.  If medical doesn't work, parotid duct transposition (great in 50%, un-do 20%)
    • MOST IMPORTANT IS TO CONTROL LACRIMAL GLAND INFLAMMATION VIA IMMUNE MODULATORY DRUGS (CYCLOSPORINE OR TACROLIMUS) IN DOGS.  HORSES GET PILOCARPINE. 
    • px: fair to poor dep on STT, maintain tx FOR LIFE so warn O.
  62. KCS differentials/etiologies for SA and LA
    • Autoimmune (most dogs): T-cell mediated lacrimal gland adenitis
    • drug-induced/toxins: parasympatolytic (atropine), tranquilizers/anesthetics, sulfa drugs, etodolac, locoweed
    • LA - gutteral pouch disease: damage to parasympathetic innervation to glands
    • Neoplasia of gland
    • THO (temporohyoid osteoarthropathy)
  63. difference between conjunctival hyperemia and episcleral injection
    • both cause red vessels around eye.  
    • hyperemia is and ocular SURFACE disease, vessels move when you tug on the conjuntiva via the eyelid
    • injection has bigger vessels with less branching, and don't really move when you touch the eyelid.  Deeper - corneal or inside.
  64. clinical signs of conjunctivitis (7)
    • conjunctival hyperemia (puff and fill with edema)
    • chemosis
    • ocular discharge (upset goblet cells increase production of mucin)
    • hemorrhage
    • follicles
    • pruritus (scratching, leads to...)
    • ulceration
  65. differential diagnoses for conjunctival disease in dogs (7)
    • infectious (uncommon)
    • staph aureus, staphy epidermidis, strep
    • distemper
    • herpesvirus
    • calicivirus

    • Non-infectious (MOST)
    • allergic (often atopic)
    • follicular conjunctivitis
    • KCS
  66. differential diagnoses for conjunctival disease in cats (5)
    • FHV-1: stress (latency), MOST COMMON.  Dendritic ulcers, rhinitis, symblepharon (conjunctiva stuck to cornea)
    • Chlamydophila felis: bilateral, chemosis, mild rhinitis, fever, enlarged submandibular LN, long term c/s.
    • mycoplasma: chemosis, uni or bilateral, ocular  and nasal d/c
    • feline eosinophilic keratoconjunctivitis: multifocal raised pink/pale white plaques, +/- ulcer.  Affects cornea, conjunctiva and 3rd eyelid.  65% also have herpes
    • lipogranulomatous conjunctivitis: blepharitis, nodular conjunctivits, upper lid of white cats
  67. differential diagnoses for conjunctivitis in horses (5-8)
    • equine herpes virus: URI! 
    • Moraxella spp: rare
    • chlamydophila abortus
    • chlamydophila pneumoniae
    • parasites: onchocerca cervicalis, habronema spp, Draschia megastoma, thelazia
  68. differential diagnoses for conjunctivitis in cattle and sheep (6-8)
    • bovine malignant catarrhal fever: HIGH mortality.  Alcephaline herpesvirus vs ovine herpesvirus
    • infectious bovine keratoconjunctivitis: moraxella bovis
    • Infectious Bovine Rhinotracheitis: Bovine herpesvirus I
    • Chlamydophila abortus
    • chlamydophila pecorum
    • Parasites: thelazia, Oestrus ovis in sheep
  69. differential diagnoses for conjunctival masses
    • non-neoplastic
    • dermoids (normal tissue)
    • subconjuntival fat prolapse
    • granulation tissue
    • cysts

    • neoplastic
    • squamous cell carcinoma (most common in all but dogs)
    • hemangioma and hemangiosarcoma (NBD in conjunctiva, doesn't spread)
    • papilloma/histiocytoma
    • mastocytoma
    • lymphoma
    • melanoma (usu malignant in cats and horses)
  70. therapeutic approaches for conjunctival diseases
    • virus: cidofovir, famciclovir, lysine
    • bacteria: doxycycline, topical tetracyclines or erythromycin, ciprofloxacin
    • immune: (feline eosinophilic keratoconjunctivitis) topical cyclosporine, topical steroids, +/- antivirals?
    • sx: (lipogranulomatous, neoplasia/mass) full removal vs debulk vs exteneration of eyeball
    • parasitic: remove parasite, ivermectins
  71. What does fluorescein tell you about corneal disease?
    • detects and evaluates corneal ulcers: hydrophobic corneal epithelium and descemet's membrane repel, hydrophilic stroma binds.  Can use cobalt filter or UV light to excite
    • seidel test: leaking aqueous humor. CONCENTRATED fluroescein (dark orange, not fluorescent), streams bright green when diluted by aqueous humor, will fluoresce
    • determines nasolacrimal patency
  72. Red - basic pathologic responses of cornea and the color changes they cause, potential causes
    • vascularization
    • result of chronic inflammation (superficial vs deep tells you where)
    • superficial: brighter red, fine, branches, cross limbus, "tree"-like, from conjunctival vessels, suggest superficial corneal or external eye disease like chronic keratitis
    • deep: darker, shorter, straighter with few or no branches, do not cross limbus, "hedge"-like.  From perilimbal ciliary vessels, suggest deep corneal or intraocular disease like glaucoma, uveitis, corneal stromal abscess
  73. Blue - basic pathologic responses of cornea and the color changes they cause, potential causes
    • edema
    • "ground glass" or "fluffy" appearance
    • epithelial or endothelial disease.
    • Epithelial: ulcers = loss of barrier function.  Focal edema, often mild.  Fluorescein +
    • Endothelial: primary or secondary dysfunction of active ion pumps with loss of barrier function.  Diffuse edema, can be marked.  Fluorescein -.  
  74. Black/Brown - basic pathologic responses of cornea and the color changes they cause, potential causes
    • pigment
    • intra- or extracellular melanin deposition.
    • Epithelial/stromal: chronic inflammation
    • Endothelial: congenital anomalies, deflated iris cysts or anterior synechiae
    • Cats with corneal sequestrum can also have brown or black but it isn't pigment.  
  75. Yellow/green - basic pathologic responses of cornea and the color changes they cause, potential causes
    • inflammatory cells - leukocytes in corneal stroma or epithelium.  Often mucusy or creamy.
    • diffuse or focal with stroma abscess formation
    • usually indicate corneal infection or foreign body, often an emergency!!
  76. greasy tan - basic pathologic responses of cornea and the color changes they cause, potential causes
    • keratic precipitates
    • plaques of inflammatory cells ADHERENT to corneal endothelium.  Usually on ventral endothelium
    • indicates prior or current anterior uveitis
  77. gray/white and wispy - basic pathologic responses of cornea and the color changes they cause, potential causes
    • scar tissue
    • flat, dull, white or grey color tone, often indistinct borders
    • results from corneal fibrosis and disorganization of stromal collagen
    • secondary to any corneal insult or injury (nonspecific)
  78. crystalline white - basic pathologic responses of cornea and the color changes they cause, potential causes
    • deposition of lipid/mineral.  Refractile, appears "sparkly", well-defined.  
    • Calicum or cholesterol most common
    • primary: inherited corneal dystrophies (irregular metabolism in cornea)
    • secondary: corneal degeneration (inflammation), systemic diseases (increase blood lipid or mineral levels)
  79. superficial vs deep corneal vessels and their significance
    • superficial: brighter red, fine, branches, cross limbus, "tree"-like, from conjunctival vessels, suggest superficial corneal or external eye disease like chronic keratitis
    • deep: darker, shorter, straighter with few or no branches, do not cross limbus, "hedge"-like.  From perilimbal ciliary vessels, suggest deep corneal or intraocular disease like glaucoma, uveitis, corneal stromal abscess
  80. superficial ulcer staining pattern, clinical appearance, time to healing
    • epithelial loss only, acute
    • distinct epithelial borders cause distinct fluorescein outline.  
    • Minimal inflammation
    • heal in days
  81. indolent ulcer staining pattern, clinical appearance, time to healing
    • epithelial loss only, chronic, with non-adherent epithelial "lip" (loose flaps). epithelial basement membrane or stromal abnormality a possibility.  ONLY IN DOGS (cats and horses have viral and fungal similar things)
    • indistinct fluorescein halo around border (pathognomonic)
    • minimal inflammation, variable corneal vascularization
    • heals in days
  82. stromal ulcer staining pattern, clinical appearance, time to healing
    • epithelial and stromal loss, acute or chronic
    • fluroescein stains walls and floor, have "depth"
    • frequently inflammation of cornea and anterior chamber
    • heal in weeks to months
  83. descemetocele ulcer staining pattern, clinical appearance, time to healing
    • complete stromal and epithelial loss, acute or chronic
    • floor does not stain, but walls do (watch for pooling)
    • corneal and anterior chamber frequently inflamed
    • floor is very clear and may bubble out - glass bottom boat!  NEVER POP A BUBBLE
    • heal in weeks to months
  84. corneal perforation ulcer staining pattern, clinical appearance, time to healing
    • full-thickness stromal and epithelial and endothelial loss, aqueous humor may leak out.
    • Fluorescein sticks to walls but not floor, floor very clear (because nothing is there). Fibrin clot (looks like mucus) or iris (iris-colored mass) may fill defect in cornea.  May be dyscoria/pulled pupil, anterior chamber may be shallow or absent and cornea may wrinkle.  Hyphema (uveal hemorrhage from rapid pressure change).
    • heal in weeks to months
  85. corneal facet staining pattern, clinical appearance, time to healing
    • chronic healed ulcer with intact epithelium
    • fluorescein may pool in dip but will wash away.
    • Thinned cornea, minimal inflammation though previous scarring, vascularization or pigment may remain. 
    • Just there to be confusing
  86. tx for superficial uncomplicated corneal ulcers
    • superficial ulcers
    • find and remove the inciting cause
    • prevent secondary infection via topical abx
    • prevent/treat reflex uveitis with atropine +/- systemic NSAID
    • prevent self-trauma with ecollar
    • recheck on 7-10 days (should be HEALED)
    • NEVER: topical corticosteroids or topical anesthetics FOR ANY ULCER, NSAIDs only in emergencies
  87. tx for superficial indolent corneal ulcers
    • indolent ulcers (only occur in DOGS for tx purposes, viral or fungal in cats and horses and this makes it worse)
    • debride loose epithelium with dry cotton-tipped swab
    • prevent secondary infection
    • prevent/treat reflex uveitis with atropine +/- systemic NSAIDs
    • prevent self-trauma with ecollar
    • may require grid keratotomy, punctate keratotomy, diamond burr debridement, contact lens, keratectomy
    • NEVER: topical corticosteroids or topical anesthetics FOR ANY ULCER, NSAIDs only in emergencies
  88. grid keratotomy
    • topical anesthetic and sedation
    • debride all loose epithelium (indolent ulcer)
    • 25g needle
    • score stroma in grid pattern
    • DOGS ONLY, 90% heal after this
  89. tx for deep complicated ulcers
    • stromal, descemetocele, perforations
    • Pretty much is or has been infected. Need prompt tx!
    • diagnostics: exam with STT, fluorescein but NOT tonometry, culture, cytology, gram stain (swab the broder not the floor)
    • find and remove inciting cause
    • topical antimicrobials based on cytology, q2-4h (Solutions only, don't touch the eye!), atropine, e-collar, monitor!  
    • Maybe: Systemic NSAIDs for analgesia and uveitis, anticollagenase to prevent active melting, EVERY 2 HOURS (acetylcysteine, EDTA, tetracyclines, serum)
    • NEVER: topical corticosteroids or topical anesthetics FOR ANY ULCER, NSAIDs only in emergency
    • Sx: only for rapid progression, deep or perforated.  Conjunctival grafts or corneal grafts to "seal" and provide blood supply (not third eyelid flap or tarsorrhaphy, just hides doesn't help)
  90. 3 reasons a superficial uncomplicated ulcer fails to heal in 7-10 days
    • inciting cause still present
    • infected
    • indolent ulcer
  91. clinical signs of infection in corneal ulcer (5)
    • infiltrates (appear yellow or green) in cornea
    • corneal edema
    • corneal melting (keratomalacia) due to enzymatic digestion from proteases from MO, leukocyte and epithelial cells.  Looks gelatinous and may have anterior displacement
    • uveitis out of proportion, more than seen in superficial ulcers
    • stromal loss (infection is the only reason they get deeper)
    • most show ALL these signs
  92. initial tx of deep complicated corneal ulcers
    • find and remove the inciting cause
    • diagnose and treat the infection
  93. diagnose and treat corneal sequestrum
    • brown/black discoloration in feline corneal stroma.  May be surrounded by ring of ulceration, +/- vascularization.  +/- painful, usu unilateral and central.  Esp brachycephalic
    • non-specific response to keratitis?  Stromal necrosis, not sure why.
    • medical tx: if not painful, resolve chronic keratitis, topical abx, antivirals and/or lubricants, it may slough in several months (or may not)
    • surgical tx: superficial keratectomy for painful.  Conjunctival or corneal grafts needed for deep sequestrum to fill defect, may prevent recurrence
  94. diagnose and treat feline herpesvirus keratitis
    • most common in cat (though appear in others).  FHV-1 MOST COMMON cause of all conjunctivitis, keratitis and corneal ulceration in cats.
    • punctate corneal ulcers are earliest, dendritic are pathognomonic for FHV (coalesce to form geographic)
    • dx: cytology (inclusions rare, rest non-specific), IFA not good, serology doesn't help since everyone has it, virus isolation is time-consuming, expensive and still false +.  PCR is sensitivit/specific but not everyone is symptomatic.  JUST DO TX, don't do tests
    • tx: prevent secondary bacterial, prevent/tx reflex uveitis, topical antivirals (cidofovir BID), lysine MIGHT prevent recurrence? Oral famciclovir. Tx all immunosuppressive conditions but avoid immunosuppressive meds and stress. DON'T DO GRID KERATOTOMY
  95. diagnose and treat equine fungal keratitis
    • aspergillus, fusarium and candida
    • predisposing: topical steroids, abx, corneal trauma, corneal FB.
    • Signs look like any ulcers
    • CLINICAL FINDINGS: white, gray, yellow, brown or black corneal plaque, fluffy or feathery appearance to lesion, satellite lesions, deep stromal abscess (usu fungal in horse)
    • dx with corneal swab, scraping or biopsy (last two preferred).  Cytology least sensitive, histopath great but hard to get sample, culture most sensitive but too slow, PCR high SE low Sp from environment, in vivo confocal microscopy is the best but limited availability
    • medical tx: prevent/tx secondary bacterial, prevent/tx reflex uveitis (balance systemic NSAID with inhibition of corneal vascularization), topical antifungals, manual debridement, systemic antifungals?  MONTHS OF THERAPY
    • surgical tx: don't respond to medical or rapid progression.  Keratectomy to remove plaques, conjunctival grafts for blood supply and support, or keratoplasty to replace lost tissue
  96. medical vs sx tx for corneal lacerations and FBs
    • medical for <50% stromal thickness, topical and systemic abx, atropine, systemic NSAIDs.  Prevent additional self-trauma
    • sx for >50% stromal thickness.  Replace/remove iris if prolapsed, suture corneal defect, refill anterior chamber, +/- corneal grafts for large, +/- lens removal if capsule compromised
  97. medical vs sx tx for corneal FBs
    • superficial removed with eyewash, Q-tip, fine forceps
    • deep need keratectomy
    • after removal, topical abx, atropine, monitor for infection.  Systemic anti-MO if penetrated anterior chamber
    • Deep can be pushed deeper, be careful and refer!
    • post-removal infections handled like deep ulcers
  98. describe clinical appearance, diagnosis and treatment of eosinophilic keratitis
    • appearance: corneal ingrowth of blood vessels, superficial white nodules or plaques, faint fluorescein staining? Focal or diffuse, unilateral or bilateral
    • diagnosis: clinical appearance and corneal cytology (ANY eosinophils present with other inflammatory cells)
    • Treatment: topical steroids and/or topical cyclopsorine.  Topical antiviral?  DON'T use systemic megestrol acetate (historical, bad effects)
    • Often controlled, not cured
  99. describe clinical appearance, diagnosis and treatment of chronic superficial keratitis (aka Pannus)
    • dogs only
    • immune-mediated disease of unknown cause (UV and genetics, GSD, shepherd crosses, greyhounds), infiltrate of plasma cells, lymphocytes, blood vessels and pigment
    • appearance: lateral cornea over corneal surface, red "fleshy" plaque  (+/- pigment, "cobblestone"), may be on nictitans or conjunctiva too.  Bilateral and symmetric. Non-painful, not ulcerated
    • ATYPICAL CSK/Pannus occurs on nictitans
    • Dx: appearance, breed, can cytology/histopath
    • tx: controlled, not cured.  Topical cyclosporine/tacrolimus, topical steroid (start with both, taper off steroid), UV light avoidance (doggles!).  Lifelong tx.
  100. describe clinical appearance, diagnosis and treatment of pigmentary keratitis
    • pigment is a non-specific response to chronic keratitis, some dogs/breeds have more (pug, peke, shih tzu, boston, from nasal trichiasis, entropion, folds, KCS, lagopthlamos/incomplete blink etc)
    • thick plaque of pigment that causes blindness without tx, takes a long time to go away.  Begins at nasal cornea and spreads, usu vascularization.
    • dx: via appearance
    • tx: correct primary problems (cyclosporine for KCS, surgical correction of face to stop irritation), then palliative (lubricants, topical cyclosporine/steroids, beta-irradiation for severe?  NO KERATECTOMY)
  101. most common primary, secondary and metastatic corneal neoplasms
    • primary: rare, papilloma (young), SCC, hemangioma/HSA. Dermoids are NOT a neoplasm
    • secondary: more common (extensions from adjacent).  SCC and HSA most common.
    • Metastatic: rare, lymphoma (salmon/pink to white corneal infiltrate. Ocular = stage 5, it's EVERYWHERE
  102. identifying and distinguishing features of the most common non-neoplastic corneal masses
    • granulation tissue: red, opaque, smooth, raised masses on cornea, highly vascular. Secondary to chronic keratitis
    • corneal epithelial inclusion cysts: raised or flat, solitary, white to pink masses, nonpainful, chronic, unlateral.  From traumatic/surgical seeding of epithelial cells to deeper cornea (no MO or leukocytes on cytology)
  103. corneal dystrophy vs corneal degeneration
    • dystrophy: lipid deposition in corneal from familial metabolic abnormality. Bilateral and symmetrical, central cornea, any layer, elliptical/racetrack, non-painful, no therapy.  Husky, CKCS, Bichon
    • degeneration: lipid or mineral deposition secondary to primary corneal disease. Unilateral, vascularization, any part of cornea, usu epithelial/subepithelial. Can cause non-healing ulcers.  Chelation therapy if painful - bind mineral in tears.  May also be caused by systemic like hyperlipidemia/phosphate/Ca, DM, hypothyroid, hyperadrenocorticism, pancreatitis, hyperparathyroid, lymphoma
  104. Treatment of endothelial dystrophy and degeneration (including complications)
    • dystrophy: heritable, corneal edema in older, usu lateral first, boston, chi, dach.  Tx with topical hyperosmotic to slow, keratectomy and conjunctival advancement hood flap. 
    • degeneration: secondary causing edema (uveitis, glaucoma, anterior lens luxation, intraocular sx), tx underlying cause!  Hyperosmotics may be palliative.
  105. most common causes of endothelial degeneration (4)
    uveitis, glaucoma, anterior lens luxation, intraocular surgery
  106. how does signalment influence limbal melanoma biological behavior?
    • benign canine primary scleral neoplasms from perilimbar melanocytes within sclera.  
    • Young dogs (2-4y): invasive, rapid growth
    • older dogs (8-11y): stationary, usually incidental.
    • Esp in golden, lab and GSD.
  107. clinical appearance and treatment options for limbal melanoma
    • dorsolateral quadrant first, smooth black mass, may invade cornea
    • tx: monitor older dogs (NBD).  Enlarging masses - make sure dx is right (not scleral extension of intraocular neoplasm).  Surgical excision, cryotherapy, beta irradiation, and/or laser photocoagulation
  108. summary of anatomic features of uvea
    • middle vascular layer
    • iris: stroma, contrictor pupillae (sphincter, PNS), anterior epithelium and dilator pupillae (SNS), posterior pigmented epithelium. Control pupil size/light, increase depth of field for near (miosis)
    • ciliary body: posterior to iris, pars plicata (ciliary processes), pars plana. Epithelial cells - inner non-pigmented, outer pigmented.  Stroma. Produce aqueous humor, accomodation, increases drainage of aqueous humor
    • choroid: posterior uvea, CT, vessels, pigmented cells, tapetum (fibrous in herbivores, cellular in carnivores).  Horses have stars of Winslow. 
    • tight jctns make barrier, fluid in eye is ultrafiltrate of blood with no proteins or cells.
  109. merle ocular dysgenesis
    homozygous merle, autosomal recessive.  Iris hypoplasia (poorly developed), corectopia (misplaced pupil), iris coloboma (sector defect in iris), microphthalmia, cataracts, equatorial staphylomas, scleral/retinal defects, optic nerve coloboma
  110. persistent pupillary membranes
    incidental, congenital, incomplete resorption of embryologic vascular structure and mesenchymal tissues.  Usually iris to iris, can be iris to lens or cornea (dysplastic)
  111. uveal cysts
    • congenital. clear (usu), pigmented or filled with blood
    • congenital or acquired
    • goldens, great dane, bostons
  112. heterochromia iridis/irides
    congenital. normal vs merle ocular dysgenesis, could come with iris coloboma or hypoplasia.  Congenital deafness in some animals
  113. iris nevus
    flat lesion, congenital, doesn't change over time, could become diffuse iris melanoma.  Freckles.
  114. iris atrophy
    • degenerative/acquired
    • progressive thinning of stroma, associated with chronic uveitis, glaucoma, age or trauma
    • can cause weak sphincter = abnormal PLR
  115. uveitis
    • exogenous (trauma, ulceration = reflex, etc) vs endogenous (systemic illness etc)
    • ocular pain, corneal edema, episcleral injection or ciliary flush, miosis, aqueous flare (increased turbidity of aqueous humor due to proteins from breakdown of blood barrier from inflammation, PATHOGNOMONIC)
    • anterior, posterior or pan
    • aqueous flare (hypopion, hyphemia), keratic precipitates, decreased IOP, retinal detachment.  Can cause synechia, phthsis bulbi (shrivel), cataract, lens luxation, virtreal degeneration, hyperpigmented iris, corneal edema. 
    • Caused by all the things
    • tx: primary cause, topical anti-inflamm (NSAID vs steriod), systemic anti-inflamm, systemic immunosuppressives, mydriatics (atropine for pain, stabilization).
  116. uveal melanocytoma
    recognition, treatment
    • common intraocular neoplasm, can become malignant melanoma.  Dark moving across eye?
    • tx with local resection vs enucleation vs exenteration
  117. uveal melanoma
    recognition, sequelae and prognosis
    • usually malignant, can metastasize
    • cats
    • remove pre-scleral involvement!  
    • causes uveitis, glaucoma, hyphema
    • 75% metastasize before enucleation
    • reasonable prognosis for survival
  118. feline diffuse iris melanoma
    recognition, sequelae and prognosis
    • slow or rapid color change of eye with raised pigment, pigmented cells floating around.  Irregular pupil?
    • dyscoria, glaucoma, metastasis, uveitis
    • tx: enucleation
  119. ciliary body epithelial tumor
    recognition, treatment and prognosis
    • dogs
    • adenoma vs adenocarcinoma, less malignant in eye than rest of body.  
    • Tx: removal of mass vs enucleation
    • Unlikely to metastasize, good prognosis for life
  120. lymphosarcoma
    • dogs and cats
    • MOST COMMON SECONDARY INTRAOCULAR TUMOR
    • often associated with FeLV in cats
  121. distinguish lenticular sclerosis and cataracts
    • lenticular sclerosis: epithelial structure within a capsule, so new cells produced but desquamation not possible.  Central lens fibers become compressed, more dense, less transparent. Bluish-grey haze but no vision loss, fundus VISIBLE THROUGH LENS.  Pupil margin more noticeable.
    • cataract: any opacity of lens or capsules.  May interfere with vision, FUNDUS NOT VISIBLE through.
  122. classify cataracts by stage of maturation (4, 2)
    • incipient: 10-15% of lens affected, tapetal reflection still visible (around), earliest cataract you can see, does not really interfere with vision
    • immature: anything between incipient and mature. tapetal reflection still visible, variable vision.
    • mature: tapetal reflection gone.  Eye is blind.  Leukokoria = white pupil
    • hypermature: lens resorption (decreased volume with same area of capsule, wrinkle, anterior chamber deeper, tapetal and vision may return, "sparkly". 

    • intumescent (immature or mature): lens "swollen", absorbs aqueous humor, shallow anterior chamber, SPLITS at suture regions
    • morgagnian (hypermature): lens nucleus sinks to bottom of liquified cortex
  123. know most common causes of cataracts for dog, cat horse
    • inherited in dogs.  Metabolic from DM common in dog too. 
    • chronic uveitis in cats/horses
    • nutrition in puppies/kittens from milk replacer
  124. explain patient selection variables influencing cataract surgery prognosis (5)
    • extent of visual defect (no vision loss means nothing to gain!!)
    • general health
    • condition of eye
    • client commitment (medication for MONTHS)
    • animal temperment (medication for MONTHS)
  125. understand etiology (1, 4), clinical signs (10) and tx of lens luxation
    • complete displacement of lens from patellar fossa. Anterior or posterior (side to side is subluxation).  Due to loss of zonular ligament support.
    • Primary etiology: inherited causing abnormal degeneration - Jack russels
    • secondary: chronic uveitis (cats), trauma (rare, needs massive force), chronic glaucoma (enlargement of globe - chronic stretch of ligaments), hypermature cataracts (contraction of lens capsule)
    • Signs: aphakic crescent (suddenly see around lens), iridodonesis (agitated mvmt of iris with eye mvmt), phacodonesis (lens), vitreal prolapse, corneal edema, shallow or deep anterior chamber, cataract, uveitis, glaucoma, retinal detachment
  126. pseudophakia
    presence of artifical intraocular lens post-sx
  127. aphakia
    absense of lens, congenital or post-sx
  128. microphakia
    small lens
  129. leniconus
    conical protrusion of lens
  130. lentiglobulus
    spherical protrusion of lens
  131. the eye is the only place in the body you can directly examine ______, ________ and __________ systems
    nervous and vascular and lymphatic systems
  132. ocular manifestations of canine distemper (6)
    • epithelial and neural tissues
    • conjunctivitis with mucoid to mucopurulent discharge
    • lacrimal adenitis (reduced tears, acute KCS)
    • keratitis, corneal ulceration
    • multifocal chorioretinitis
    • optic neuritis
  133. ocular manifestations of canine infectious hepatitis (CAV-1) or modified live vaccine (2)
    • corneal edema ("blue eye" in puppies)
    • anterior uveitis
  134. ocular manifestations of feline immunodeficiency virus (6)
    • conjunctivitis
    • anterior uveitis
    • pars planitis
    • lens luxation
    • retinopathy (multifocal thinning and hemorrhage)
    • uveal lymphoma
  135. ocular manifestations of feline leukemia virus (4)
    • Retinal dysplasia
    • uveitis
    • uveal lymphoma
    • spastic pupil syndrome (alternating dilation and constriction due to inflammation of autonomic ganglia, precursor to lymphoma, poor px)
  136. ocular manifestations of feline infectious peritonitis (7)
    • disseminated pyogranulomatous vaculitis, more common with dry form
    • anterior uveitis
    • hyphema
    • chorioretinitis
    • retinal hemorrhage
    • retinal detachment
    • retinal perivascular exudates (vessels cuffed in white fluffy-ness)
    • optic neuritis
  137. ocular manifestations of feline calicivirus (1 + systemic)
    • ocular: ulcerative conjunctivitis
    • systemic: URI, oral ulceration, +/- polyarthritis
  138. ocular manifestations of feline herpesvirus-1 (7 from chronic/latent, 2 from primary)
    • initial = URI, conjunctivitis, limited keratitis
    • can cause chronic, recurrent ocular disease (conjunctivitis and keratitis)
    • corneal sequestrum
    • eosinophilic keratitis
    • stromal keratitis
    • KCS
    • uveitis
  139. ocular manifestations of feline panleukopenia virus (in utero) (1)
    • retinal dysplasia
    • usu + cerebellar hypoplasia
  140. ocular manifestations of papillomavirus
    • pedunculated cauliflower-like masses on eyelid, conjunctiva, cornea.  
    • Self-limiting, otherwise healthy
  141. ocular manifestations of systemic mycoses like blastomyces, coccidioides, histoplasma, cryptococcus or disseminated opportunists like candida, aspergillus, sporothrix etc (7)
    • blepharitis
    • orbital abscess/cellulitis
    • conjunctivitis
    • keratitis
    • granulomatous anterior uveitis and chorioretinitis
    • retinal detachment
    • optic neuritis
  142. ocular manifestations of canine brucellosis (4)
    • anterior uveitis
    • chorioretinitis
    • endophthalmitis
    • +/- intraocular hemorrhage
    • often unilateral (MAKES NO SENSE). Zoonotic
  143. ocular manifestations of rickettsial infections (ehrlichia, anaplasma, rickettsia)
    • anterior uveitis, hyphema, retinal hemorrhages, chorioretinitis, optic neuritis
    • lesions due to thrombocytopenia, vasculitis, hyperviscosity
  144. ocular manifestations of borreliosis (7)
    • conjunctivitis
    • anterior uveitis
    • corneal edema
    • retinal hemorrhages
    • chorioretinitis
    • retinal detachment (direct or indirect)
    • uveal hemorrage (indirect, glomerulo-nephritis and hypertension)
  145. ocular manifestations of toxoplasma gondii (6)
    • anterior uveitis
    • chorioretinitis
    • extraocular myositis
    • scleritis
    • vitritis
    • optic neuritis
  146. clinical manifestations of uveodermatologic syndrome (aka Vogt-Koyanagi-Harada)
    • immune-mediated disorder targeting melanocytes (eyes and skin in dogs)
    • ocular: anterior and posterior uveitis, uveal depigmentation, retinal detachment
    • dermatologic: poliosis (whitening of hair) and vitiligo (skin depigmentation)
  147. list systemic diseases that can result in intra- or extraocular hemorrhage
    • hypertension
    • thrombocytopenia/coagulopathies (rodenticide)
    • hyperviscosity syndrome
    • anemia
    • diabetes mellitus
  148. describe etiology, progression and associated systemic manifestations of feline central retinal degeneration
    • initial lesion in area centralis, mirror image, line connecting the two, progressing to generalized retinal degenration
    • caused by taurine deficiency (with DCM) in cats.
  149. know most common systemic neoplasms that metastasize to the eye
    • lymphoma - MOST COMMON IN DOGS AND CATS
    • HSA
    • osteosarc
    • malignant melanoma
    • mammary and pancreatic adenocarcinoma
    • mast cell tumors
    • SCC
    • transitional cell carcinoma
  150. list systemic toxicities resulting in KCS
    • sulfa antimicrobials
    • etodolac/acetominophen
  151. list the steps in ocular therapeutic decision-making
    • define clinical problem specifically for the P
    • assess the cause
    • formulate specific objectives of therapy - medical, surgical
    • Consider options: medical vs surgical
    • educate clients: benefits and limitations of tx, prognosis for life/function/cosmetic, short and long term cost
    • assess therapeutic effect (reasons for failures)
    • surveillance for local/systemic side effects
  152. 5 routes of drug administration to tx ocular disorders and ocular anatomic locations appropriately treated by each.
    • topical: eyelid, cornea, conjunctiva (+/- iris, ciliary body)
    • subconjunctival: cornea, iris, ciliary body, anterior chamber (+/- choroid, retina)
    • retrobulbar: NOT INDICATED
    • intracameral (anterior chamber)/intravitreal (vitreous) 
    • systemic: eyelids, orbit, uvea, retina, optic nerve, anterior and posterior chambers, and vitreous
  153. Routes of administration most commonly used in ophthalmic primary care
    topical, systemic
  154. properties of solutions/suspensions vs ointments
    • solutions/suspensions: short contact time, high application frequency, drug solubility limitations, stability
    • ointments: longer contact time, lower application frequency, could worsen discharge
  155. treatment objectives are formulated for the most ___________ diagnosis
    specific
  156. therapeutic objectives that generate specific tx plans for corneal erosion (2)
    • prevent infection: abx
    • prevent/treat anterior uveitis: atropine
  157. therapeutic objectives that generate specific tx plans for superficial to indolent ulcers (4)
    • prevent infection: abx
    • prevent/treat anterior uveitis: atropine
    • remove nonadherent epithelium: Q-Tip debridement
    • encourage epithelial adhesion: punctate/grid keratotomy +/- tarsorrhaphy +/- nictitans flap
  158. therapeutic objectives that generate specific tx plans for deep stromal ulcers ("non-infected" descemetocele) (3)
    • prevent infection: abx
    • preserve pupil/pan relief: atropine
    • wound support: cyanoacrylate adhesive (glue), conjunctival flap (NOT nictitans flap)
  159. therapeutic objectives that generate specific tx plans for stromal ulceration ("infected") (4)
    • treat presumed infection: intensive abx
    • prevent/treat stromal "melting": abx, anticollagenase drugs
    • treat anterior uveitis: atropine
    • support weakened cornea: conjunctival flap
  160. therapeutic objectives that generate specific tx plans for conjunctivitis (2)
    • treat cause: abx, steroids
    • reduce chemosis (edema): topical hyperosmotic
  161. therapeutic objectives that generate specific tx plans for KCS (5)
    • stimulate lacrimation: topical cyclosporine/tacrolimus
    • replace tears: artificial tears
    • treat infection: abx (intermittant)
    • reduce corneal, conjunctival inflammation: steroids (intermittant)
    • reduce discharge: hygiene
  162. therapeutic objectives that generate specific tx plans for anterior uveitis (4)
    • reduce inflammation: steroids, NSAIDs, atropine
    • tx infection (bacterial, rickettsial, mycotic etc): abx etc PRN
    • preserve pupil: atropine, phenylephrine
    • prevent/treat secondary glaucoma: CAIs, beta-blockers, +/- prostanoids
  163. therapeutic objectives that generate specific tx plans for primary glaucoma (4)
    • reduce vitreous volume: oral/IV osmotics
    • decrease aqueous production: CAIs, beta-blockers, prostanoids, cyclocryosurgery, laser cycloablation
    • increase aqueous outflow: prostanoids, surgery
    • prevent glaucoma in fellow eye: lifetime prophylaxis with topical CAI, +/- beta blocker
  164. therapeutic objectives that generate specific tx plans for secondary glaucoma (4)
    • decrease aqueous production: CAIs, beta-blocker
    • decrease inflammation if present: NSAIDs +/- steroids
    • decrease vitreous volume: osmotic agents
    • decrease fibrin: TPA into anterior chamber
  165. therapeutic objectives that generate specific tx plans for orbital cellulitis (3)
    • treat infection: abx
    • relieve inflammation/swelling: anti-inflammatories, perioral drainage
    • eliminate inciting cause: check teeth, sinuses, r/o FB
  166. therapeutic objectives that generate specific tx plans for optic neuritis/neuropathy (2)
    • decrease inflammation: NSAIDs, systemic steroids
    • prevent/treat infection: +/- abx, +/- antifungals (systemic)
  167. therapeutic objectives that generate specific tx plans for bullous retinal detachment (2 (3+1)
    • treat primary cause: reduce choroiditis (NSAIDs, steroid), reduce hypertension (diruetics, antihypertensive drugs), tx infections (abx, antifungal)
    • encourage reattachment: duretics, tranquilizers, corticosteroids, all have ?
  168. definition of glaucoma
    group of ocular diseases that cause high intra-ocular pressure causing optic nerve and retinal disfunction, causing loss of some or all vision
  169. aqueous humor production, conventional vs unconventional outflow
    • production: active secretion (80-90%), small amt of diffusion, ultrafiltration (pressure sensitive)
    • 1-1.5% of anterior chamber volume / minute
    • conventional pathway - outflow: from CB through posterior chamber, pupil, anterior chamber, iridocorneal angle. 
    • unconventional pathway - outflow: leaks out through uvea and into sclera, resorbed by conjunctiva etc.  Some goes into vitreous and cornea, but negligible.
    • glaucoma usually due to outflow problem
  170. primary and secondary glaucoma examples
    • primary: iridocorneal angle (closed angle*, open angle, narrow, dysgensis) vs congenital (rare)
    • secondary: uveitis, intraocular neoplasm, hyphema, lens luxation, intumescent (swelling) cataract, post-sx
  171. clinical signs of glaucoma
    • red eye - episcleral vessels (not conjunctival), so dark, thick, not branching. Cats don't get this
    • lens luxation
    • haab's stria (stretch marks) on descemet's membrane (aphacik crescent)
  172. schiotz tonometer
    • the old one - weights, have to use the chart.  Not user friendly
    • inexpensive and reasonably accurate?
    • can't use in small corneas, cornea has to be horizontal, needs topical anesthesia, hard to use with low IOP
  173. Tonopen/applanation tonometer
    • reliable, simple, low maintenance cost, but expensive at first, topical anesthesia and a bit of a learning curve
    • the pen you just tap to the eye
    • recommended for GP
    • gives a standard deviation so you know how accurate the reading is
  174. Rebound tonometer/tonovet
    • No topical anesthesia needed!  Calibrated for dif species, okay in small corneas, reliable
    • but expensive and high maintenance costs
    • require vertical cornea
    • has probe that taps onto eye, can shoot off if not close enough
  175. normal IOP in species
    • dogs 16.7
    • cats 19.7
    • horse 23-39
    • hawk 20.6
  176. glaucoma fundic exam
    "cupped" ocular nerve--darker, has a halo around it.  Vessels dive in, don't show on surface like they normally do
  177. medical treatment for glaucoma
    • prostaglandin F2alpha: increase unconventional pathway outflow, increase conventional outflow, can decrease 30-40mmHg in an hour!  BID. Not good with lens luxation as causes miosis, darkens eyelashes and skin (Latanoprost)
    • hyperosmotic: dehydrates everything, mannitol.  Short term but fast, opens iridocorneal angle. Good for pre-op lens luxation.  No good for uveitis (blood barrier not intact?)
    • carbonic anhydrase inhibitors: no water goes into eye.  Topical rather than systemic. Dorzolamide TID. Increases retinal and ciliary blood flow so protective.
    • beta-blockers: timolol, decreases production of aqueous humor, don't use with ulcers (toxic to epithelium)
  178. tx differences in primary vs secondary glaucoma
    • in primary you need to treat the second eye prophylactically
    • in secondary you obviously treat the primary cause.
  179. surgical treatment for glaucoma (acute vs chronic, primary vs secondary)
    • meds not working?  
    • Acute primary: cyclodestruction (CB destruction - inject gentamicin and dexamethasone), Gonioimplant to help drain. 
    • acute secondary: enucleation, evisceration/prosthesis, cyclodestruction?
    • chronic: enucleation, evisceration/prosthesis, cyclodestruction?
    • Decrease production by killing CB or increase outflow with a shunt (hydrostatic) that releases outside sclera
    • Avoid prosthesis in cats or cancer
  180. Surgical repair for eyelid lacerations
    • Minimal debridement
    • perfect apposition of lid margin with figure 8 suture pattern
  181. prognostic indicators, potential complications and tx of traumatic proptosis
    • Px: vision - guarded to poor.  Globe retention poor if ruptured, three or more muscles torn, hyphema, facial fractures, O unable to tx 
    • complications: lateral strabismus, KCS, corneal ulceration, glaucoma, phthisis bulbi, eventual need for enucleation
    • tx: enucleate or replace globe with temporary tarsorrhaphy (horizontal mattress), when in doubt replace. Oral and topical abx, systemic NSAIDs, ecollar
  182. classical clinical signs and medical tx for infected corneal ulcer
    • Signs: depth!  Reflex uveitis, WBC infiltration, keratomalacia/melting.
    • tx: REFER with ecollar! Surgical (conjunctival graft) for >50%, Medical if <50% (abx DROPS, pain control/atropine, systemic NSAIDs, topical antiprotease/anticollaginase, ecollar
  183. clinical signs and ddx for hyphema, uveitis
    • Clinical signs: (same) aqueous flare, miosis, iridal color change, keratic precipitates. Hyphema (blood in anterior chamber)
    • ddx: (hyphema = uveitis) coagulopathy (hyphema),
    •   LOCAL: trauma, primary neoplasia (rare), immune-mediated
    •   SYSTEMIC: anything that causes vasculitis - neoplasia, immune-mediated, infectious, idiopathic (50%)
  184. dog breeds predisposed to primary glaucoma
    • Cocker spaniel
    • basset hound
    • beagles
    • siberian husky
    • shar pei
    • chow
  185. dog breeds predisposed to anterior lens luxation
    Small terriers (rat terrier, Manchester, jack Russell)
  186. list tx options for glaucoma
    • Topical: prostaglandin analogues (latanoprost for dogs), carbonic anhydride inhibitors (dorzolamide), beta blockers (timilol)
    • IV or oral osmotics: mannitol (IV), glycerol (PO), stopgap
    • Anterior chamber paracentesis: stopgap
    • sx: chemical cycloablation (IV gentamicin to kill everything, evisceration and prosthesis, enucleation
  187. list tx options for uveitis
    • Tx underlying cause
    • anti-inflammatory corticosteroids if no ulcer
    • control cycloplesia with atropine unless glaucoma
    • +/- glaucoma meds PRN (dorzolamide)
    • systemic therapy (anti-inflammatories or doxy?)
  188. list tx options for anterior lens luxation
    • Pressure-reducing meds: dorzolamide (NOT LATANOPROST) topically, methazolamide PO if needed, Mannitol IV if needed
    • REFER for IntraCapsular LensEctomy (ICLE)
    • tx uveitis in cats
  189. list differentials and diagnostic recommendations for sudden blindness with normal (amaurosis) vs abnormal ophthalmic exam
    • Amaurosis: 
    • Ddx: Retrobulbar optic neuritis, central blindness/neuro, SARDS
    • dx: electroretinogram shows retinal function (+ = neuro, - = SARDS)

    • abnormal fundus
    • ddx: opaque media, glaucoma, retinal detachment, optic nerve papilloedema, optic neuritis
    • dx: SO MANY THINGS
  190. Which emergency cases should be referred (and quickly) (4)
    • Infected ulcers
    • penetrating or perforating corneal FB
    • corneal lacerations
    • anterior lens luxation
  191. Idiopathic pendular nystagmus in dairy cattle
    • rapid horizontal nystagmus persisting throughout life in Holsteins and Guernseys
    • asymptomatic happy cows
    • familial
  192. with non-painful, acute, subacute or chronic exophthalmos in a dairy cow, until proven otherwise, the #1 rule-out is
    Lymphosarcoma
  193. orbital lymphosarcoma
    • Exopthalmos without pain or fever in adult dairy cattle!!!  
    • Rapidly or slowly progressive, unilateral or bilateral +/- lymphadenopathy
    • usu older, BLV positive
    • COMMON LOCATIONS: Orbit, abomasum, spinal cord, uterus, R atrium
    • dx: CBC, BLV test, cytology of orbit aspirate (LYMPHOCYTES = DX)
    • tx: salvage procedure to wait for calving - permanent tarsorrhaphy
  194. Bug-eyed cow vs pathological exophthalmos differentiation
    Retropulse to r/o space-occupying mass like LSA
  195. Bovine Squamous Cell Carcinoma, signalment, common sites (3), behavior
    • Most common tumor of globe in cows, causes 10% of carcass contaminations
    • signalment: middle-aged to older (7-9y), cows with little periocular pigmentation.  UV and irritants are risk factors, also viruses
    • common sites: nictitans, temporal limbus, lid margins
    • behavior: locally aggressive, rarely metastatic
  196. equine squamous cell carcinoma, signalment, risk factors, most common sites (3)
    • most common tumor of GLOBE in horses (sarcoidosis is most common skin)
    • Signalment: middle aged to older, lightly pigmented coat/ocular areas, BELGIANS, HAFLINGERS, APPALOOSA and any CHESTNUT
    • Risk factors: solar radiation (geographic location), chronic inflammation/irritation, loss of pigment in temporal perilimbal conjunctiva (onchocerca sp)
    • most common sites: nictitans, temporal limbus, lid margins
  197. Classic SCC appearance
    • Cauliflower-like mass on nictitans or temporal limbus
    • VERY variable (smooth, gelatinous, scaly, flat, discoid, exudative like fungal keratitis, often cheesy-looking).  Mimics other disease, ALWAYS keep SCC in mind
    • can involve lids, nictitans, caruncle, conjunctiva, cornea or combinations
    • THINK OF WITH ANY CHRONIC OCULAR LESION
    • never forget to check the penis
  198. SCC diagnosis, prognosis
    • Dx: clinical appearance/exam, BIOPSY AND HISTOPATH (not cytology, looks like reactive epithelium)
    • prognosis: directly proportional to SIZE, age, etc.  Histo very important!  Local recurrence common, but you can buy years and repeat as needed. RADIATION as cleanup helps a lot!!
    • small lesions on nictitans or globe are fair/good, lid always guarded.  Large, ulcerated and all caruncle is poor
    • REMOVE ASAM
  199. SCC treatment
    • pre-op NSAIDs, broad-spectrum topical abx, atropine
    • local excision (IMMEDIATELY)
    • follow with Sr90 (best, radiation for LA), cryo or mitomycin or radiofrequency hyperthermia (may do nothing or hurt)
    • enucleation if inoperable
    • follow with radiation (Sr90), SCC is VERY radiosensitive but only penetrates ~1mm (clean-up, will delay healing)
  200. sarcoids, tx
    • Most common skin tumor of horse, VERY common in eyelid, esp medial aspect of superior
    • tx: cryo, BCG, ALDARA (?), xxterra not near eyes
  201. habronemiasis def, signalment, location
    • Granulomatous reaction to L3 larvae of habronema (majus and muscae) and draschia megastoma deposited in moist tissue (WOUNDS! medial canthus, urethral orifice, lacrimal caruncle, nasolacrimal duct) by flies (house and stable)
    • Signs: eye or skin inflammation with ulcerative lesions containing SULPHER BODIES (moist areas with yellow caseious hard gritty concretions).  Inflammation erodes skin away!!
    • derm disease, affects equine eye in warm climates (and NY)any age (often young to middle)common in ARABS AND LIGHTER COAT COLORS
    • don't forget to look at the penis!
  202. habronemiasis dx, tx
    • dx: presentation, lesions, season. Granulomatous reaction with eosin, mast, collagenolysis (~50% will find larvae, rare to find on cytology)
    • tx: REMOVE all granules and necrotic tissue, deworm, NSAIDs, topical steroids if cornea healthy.  Control flies, remove manure, PRAY for cold weather.  Catheterize nasolacrimal ducts if needed, may retain patency
  203. Onchocerca species presentation/signs, tx
    • Horses.
    • follicular keratoconjunctivitis, temporal limbal vitiligo (loss of pigment at lateral limbus of iris).  Alopecia, pruritus, scaling, lichenification esp along ventral midline
    • tx: ivermectin, tx inflammation in eye PRN
  204. Infectious bovine rhinotracheitis signs
    • bovine herpesvirus 1 can cause conjunctival, respiratory, abortion, IPV, encephalitis, viremia.  They are SICK usu
    • ocular presentation: uni or bilateral, acute serious conjunctivitis with epiphora, purulent d/c 1-3d later, mild to severe chemosis.  Raised white to reddish plaques on conjunctiva, coalesce. Possible peripheral corneal edema (IBK is central), non-ulcerative keratitis, secondary anterior uveitis
  205. infectious bovine rhinotracheitis tx, prevention, prognosis
    • tx: supportive, topical BSA if severe conjunctival dz
    • prevention: vaccination, but will make IBK worse if already present
    • prognosis: lesions resolve in 2-3wk, but can cause latency (STRESS)
  206. importance of ocular IBR
    Infectious bovine keratoconjunctivitis, aka Pinkeye
  207. infectious bovine keratoconjunctivitis (IBK) MO
    moraxella bovis (gram negative rod with 3 forms), mycoplasma bovoculi and more produce toxins, hemolysins, dermonecrolysins.  + inflammation = rapid tissue destruction (keratomalacia)
  208. Infectious bovine keratoconjunctivitis (IBK) signalment, predisposing, spread, seasonality
    • any age bovine (usu 6-24mo), most don't get re-infected
    • predisposing: UV!!  esp after snow, floods, decreased ocular pigment, irritants. NONE needed in virulent strains.  Worse around IBR outbreak times or vaccination.
    • spread: face fly
    • season: late spring/summer in young animals, winter in all animals
  209. infectious bovine keratoconjuctivitis signs
    • NOT systemically ill
    • sore, red eye (conjunctivitis) with epiphora, blepharospasm
    • several animals at once
    • unilateral or bilateral
    • keratitis within 24-72h
    • FOCAL CENTRAL EDEMA that ulcerates (IBR is peripheral)
    • ulcers can be small or large and deep, abscesses, can persist for weeks.  Desmetoceles common, some will perforate (bovines are tough, give them time to heal). Can get reflex uveitis
  210. how to tell how long corneal disease has been going on
    vessels take 4-5days to be visible, then grow 1mm/day
  211. infectious bovine keratoconjunctivitis treatment
    • begin ASAP
    • remove inciting causes, isolate affected (careful with Rx, some are illegal in food-producing)
    • SID (b/c farmers won't do more): subconjunctival abx injection, topical abx, topical atropine, systemic oxytetracycline (approved, others used).  Tx ALL HERD.  
    • Tx may not work, return to comfort important
  212. IBR vs IBK in eye
    • IBR: no corneal involvement acutely, corneal ulceration rare, peripheral edema, conjunctival plaques, systemically ill
    • IBK: central edema, no conjunctival plaques, feel systemically fine
    • Vax for IBR may cause IBK or make it worse
  213. pinkeye in sheep and goats MO, signalment, presentation, HALLMARK, dx
    • chlamydophila/mycoplasma complex (NOT THE SAME as in cattle)
    • no signalment, can be re-infected.  
    • Uni or bilateral, intense conjunctivitis for 1-3d.  Epiphora, chemosis, hyperemic conjunctiva +/- hemorrhages, painful. Serous d/c turns mucopurulent after 3-4d, corneal edema, neovascularization, uveitis, polyarthritis, fever with chlamydophila.  Usu no ulceration
    • Hallmark: follicular lymphoid hyperplasia and conjunctival folds hallmark of chlamydophilosis
    • dx: exfoliative cytology of palpebral conjunctiva (intracytoplasmic inclusions in epithelial, culture (special for chlamydophila)
  214. microphthalmos with BVD
    in utero BVD infection 76-150d = CNS anomalies (microencephaly, cerebellar hypoplasia, hydrocephalus, hydrancephaly) or eyes (microphthalmos, cataracts, retinal dysplasia, pigment changes, hemorrhage)
  215. cyclopia
    • common in ruminants if vertrum californicum ingested on gestational day 14-15
    • This is happening in humans!!!  False hellebore ingested for morning sickness instead of true hellebore!
  216. entropion in lambs
    • 80% in some herds
    • increased incidence after new male introduced
    • tx: correct!  Rarely requires skin incision
  217. uveitis in lepto and lyme
    uveitis is common in horses, caused by both lepto and borrelia!  Lepto MUCH more significant and causes RECURRENT (lepto, serovar pomona).  Vaccine now available
  218. vitamin A in feedlot cattle
    • deficiency can cause blindness in feedlot or growing cattle secondary to stenosis of optic canals
    • clinical dz in young (blind, occurs a few months after serum vitamin levels fall
  219. vitamin A in pigs
    • wide spectrum of ocular defects seen in piglets of deficiency sows 
    • anophthalmia, microphthalmia, cataract, retinal dysplasia, colobomas etc
  220. Functions of rod vs cones, tapetum
    • Tapetum: wavelengths transformed to best wavelength for species, then bounce to re-present to rods and cones
    • rods: dim light vision, 1000s:1 so diffuse vision (scotopic, max sensitivity in darkness)
    • cones: color and bright light, 1:1 in brain so detailed (photopic, max acuity in light)
  221. Basic neurophysiology of vision
    • 3-neuron component.  
    • Rods and cones outside, middle is translucent to allow light to pass through
    • 1st-order electric current generated (pigment epithelium and photoreceptors layer), then 2nd (bipolar cells, layers 3-7) transmit/interneuron, 3rd (layers 8-10) ganglion cells next to vitreous collect and transmit through optic nerve to lateral geniculate nucleus.  
    • LGN/optic radiation/visual cortex
  222. normal vascular pattern and extent of retina by domestic species
    • Choriocapillaris nourishes retinal pigment epithelium/outer layer
    • retinal vessels nourish inner layer, on inner third.  
    • Vary considerably
    • Holangiotic (whole lot of vessels): primate, carnivore, ruminant, rat, mouse
    • merangiotic (butterfly around disc): rabbit
    • paurangiotic (tiny vessels, don't extend far. Some just a tuft): horse, guinea pig
    • anangiotic (no visible vessels): bird, beaver, chinchilla, bat, reptile, amphibian
  223. spatial relationship of tapetum to retina pigmentary epithelium and choroid
    • Choroid underlies retinal pigment epithelium
    • tapetum is inner layer of choroid.  Retinal pigment epithelium is not pigmented over tapetum
  224. 3 steps to evaluate fundus
    • Background: quality of tapetal reflections and non-tapetal area (brown or black)
    • vessels: pattern and extent
    • optic nerve head: size, shape, color and vascularity
  225. basic embryology of retina, choroid, sclera, optic nerve and vitreous
    Invagination of surface ectoderm causing optic cup.  Inside makes lens.  Retina: inner (9 layers of neural) and outer layer (pigmented retina) of optic cup. Potential space in between is area of detachment - just interdigitate with villi on retinal pigment epithelial cells. Electrostatic attachment.
  226. Acquired retinal disorders
    • Detachment - separation in intraretinal space
    • dysplasia - Panleuk, FeLV?, BVD
    • dystrophy
    • degeneration (primary = genetic, secondary can be metabolic, nutrition, sequelae)
    • Metabolic (SARD and hyperthyroid)
    • nutritional (taurine in cats, vitamin E in horse and dog, vitamin A)
    • inflammation/infection
    • trauma/toxicity
  227. congenital disorders of the retina and optic nerve
    • Coloboma: embryological defect (paper punch hole) in tissue closure, typical at 6 o'clock (Last place it fuses, fetal fissure) and atypical anywhere else.
    • dysplasia: abnormal formation. Classified by how much involved. photoreceptors only (genetic rod or rod-cone dysfunction) vs panretinal thickness dysplasia (multiple layers: folds (tiny), geographic (bigger), detachment/non-attachment (whole))
  228. 3 mechanisms causing retinal detachment
    • Pushed off: exudative
    • Pulled off: traction
    • Perforated: torn
    • There is also dysplasia, never attached at all - most common
  229. how uveal disorders affect the retina and its function
    Usually chorioretinitis too!
  230. potential causes, clinical signs and progression of diffuse retinal degeneration
    • Causes: inherited in dog, dif reasons in dif species?
    • optic signs: vessel attenuation, altered tapetal reflectivity (tin foil), optic disc pallor, nontapetal fundus depigmentation, secondary cataract
    • signs/progression: night blindness, mydriasis, day blindness, secondary cataract (late stages)
  231. distinguishing features of active vs inactive focal retinal lesions
  232. 2 causes of sudden blindness in dogs with normal fundi and clear ocular media
    • sudden acquired retinal degeneration (SARD)
    • optic neuropathy
  233. systemic and ocular signs of canine SARD, how it is diagnosed and its prognosis
    • Sudden blindness, PUPD, polyphagia, weight gain, mydriasis, normal fundus initially
    • ERG - absent!
    • don't get better, just adjust
  234. clinical and optic signs of optic neuritis/neuropathy, general categories of causes and potential tx
    • "Sudden" blindness +/- disc swelling, mydriasis, normal fundus otherwise.
    • Causes: GME, infections (mycoses or distemper), neoplasia (LSA)
Author
XQWCat
ID
331344
Card Set
ophtho
Description
Block Va Ophthalmology
Updated