cornea questions.txt

Card Set Information

cornea questions.txt
2013-03-19 17:58:34

Show Answers:

  1. what percent is peter's anomaly b/l
    60 percent
  2. what do you use to take a viral swab
    dacron swab
  3. what's the most accurate way to take pachymetry
    u/s pachymetry
  4. does optical pachymeters from pentacams and orbscams underestimate or overestimate the true CCT
  5. what is an inflamed limbal area with leukoplastic lesion growing into cornea that only involves epithelium
  6. what is the most common ocular manifestation of reactive arthritis
    papillary conjunctivitis
  7. what is reactive arthritis or Reiter's syndrome
    "gram negative dysentery (salmonella, shigella, yersinia) or non-gonococcal urethritis caused by chlamydia -> arthritis (usually hla-b27+ in 75% of patients)"
  8. what is fleck dystrophy
    "dandruff like flecks in the stroma (sparing epithelium/endothelium), autosomal dominant, does not affect vision (only invovlement of epi/endothelium affect vision)"
  9. what are indiciations for ac washout for hyphema
    1. IOP > 60 for 2 days 2. IOP > 35 for 7 days 3. IOP > 25 for 1 day in sickle cell patient 4. any sign of corneal blood staining
  10. where are the palisades of vogt
    1-2mm posterior to limbus where tenons fuses with conjunctiva
  11. what are indications for interrupted sutures in a PK
    1. thin cornea 2. vascularized cornea (can take out sutures where graft is vascularized in specific areas) 3. inflamed corneas 4. children
  12. are iron lines typically visually significant
  13. what are adenochrome deposits
    "deposits on cornea with little clinical significance, can be due to chronic epinephrine drop exposure"
  14. what infections do you see Halberstaideter-Prowazek bodies
  15. what agent plays the largest role in inflammation in hsv stromal keratitis
  16. what is a wessely immune ring
    "represents coalesecnce of antibodies to antigens with subsequent complement activation, type 3 HSS reaction "
  17. what can cause a wessely immune ring and what does it look like
    "several small, peripheral, ring-shaped corneal infiltrates in the inferior cornea; ddx includes neomycin ointment, corneal foreign body, contact lens reaction"
  18. what diseases are type I hss
    allergic/atopic conjunctivitis
  19. what diseases are type II hss
    ocular cicatricial pemphigoid
  20. what diseases are type III hss
    "SJS, scleritis"
  21. what diseases are type IV hss
    "contact dermatitis, corneal graft rejection"
  22. what does rose bengal stain? What does fluorescein stain?
    dead and devitalized epithelial and conjunctival cells; epithelial basement membrane
  23. what does rose bengal do to hsv
    can inhibit hsv replication
  24. what size perforations can you use glue
    less than 1-2mm
  25. what is the treatment for CIN
    "surgical excision with 4mm margins and cryo to bordering conjunctiva; MMC drops, 5-FU drops"
  26. what should you do if you get a descemet's tear from phaco wound after ceiol
    place air bubble in the anterior chamber (dsaek shows us that air bubble is good for repproimating descemet's to stroma
  27. how does schyner corneal dystrophy present
    "second-third decade of life -> corneal opactification starts centrally and next develops in the periphery (arcus lipoides), and then midperiphery -> subepithelial crystals -> then reduced K sensation"
  28. what systemic disease is schynder corneal dystrophy associated with
    high cholesterol
  29. what is inheritance of schyder dystrophy and what gene is involved
    AD; UBIAD1
  30. what stain used for schynder K dystrophy
    oil red O;
  31. what is treatment for molluscum
    complete excision or an incision in center of lesion; cryotherapy (less recommended)
  32. what corneal dystrophy presents earliest
  33. how long should you wait to enucleat a ruptured globe injury before increasing risk of SO
    2 weeks
  34. what are ocular manifestations of porphyria cutanea tarda (tea colored urine)
    "symblepharon, bullous pemphygoid"
  35. what is used to culture nocardia and mycobacteria
  36. what can aerobic bacteria be cultured with
    "chocolate, Blood, thioglycolate broth"
  37. what can anaerobic bacteria be cultured with
    thioglycolate broth
  38. what is the classic presentation of thygeson superficial punctate keratitis
    "small punctate eleavted epithelial lesions on central cornea b/l, with negative staining -> photophobia and FBS ou"
  39. what is the inittial treatment for thygeson
    "ats, restasis also effective but not first line, PF can be used by high risk of recurrence after stopping"
  40. what is treatment for HZO? Immunocompromised? Postherpetic neuralgia?
    1. acyclovir 800 mg 5x/day for 7-10 days 2. IV acyclovir 3. oral amitriptyline
  41. what is tx for gonococcal conjunctivitis if PCN allergy
    intramusclar spectinomycin x1 or oral fluoroquiniolones x5-7days
  42. what is difference between ched 1 and 2
    "ched 1 is AD, clinical signs do not appear until 1-2 so the visual system develops and you don’t get nystagmus; CHED2 is AR, more common, clinical signs appear at birth so visual system doesn’t develop and you get nystagmus; both get blueish tint to cornea due to thickening"
  43. what type of HSS reaction is staph marginalis
    type IV
  44. what are CI for donor cornea for dsaek
    "leukemia, bacterial endocarditis, active septicemia"
  45. what glands are responsbile for aqueous components of tears
    "lacrimal, krause glands, glands of wolfring"
  46. according to HEDS what is tx for stromal keratitis from HSV
    "topical trifluridine and topical steroids; although most people treat with acyclovir and topical steroids, this wasn't tested in HEDS; also give acyclvori ppx for more than 1 episode"
  47. what inferior fornicial depth suggests OCP
  48. what is the pathophysiology of ocp
    autoantibodies directed against bullous pemphigoid antigen II (BP180) in the basement membrane zone (bmz)
  49. how do you treat OCP
    cyclophosphamide in severe disease
  50. is OCP b/l or u/l
  51. do you have preservatino of scopotic or photopic vision in schnider's dystrophy? Why?
    "scoptoc vision; in the darkness, pupil is dilated so light can pass around the central K opacity"
  52. what is infantile cystinosis
    "associated with dwarfism and renal impairment, AR, corneal crystals appear at 1yo and deposited in anterior cornea"
  53. "what aa deficiency presents with pseudomembranes, recurrent dendrites, mental retardation"
  54. what is fabry's disease
    x-linked disease with renal failure and peripheral neuropathy; cornea verticilata (no cherry red spot);
  55. what sphingolipodase has cherry red spot
    tay sachs
  56. what is the pathophysiology of disciform keratitis
    endothelitis results in round edema of stroma and epithelium
  57. what is benzalkonium chloride
    common preservative in topical medications that increases the potency by causign a disruption in epithelial cells
  58. why should you use oral acylovori in disciform keratitis
    oral acyclovir can better penetrate to endothlium through the aqeous
  59. are acids or bases more likley to precipitate corneal proteins
  60. do acids or bases more likely to lead to glaucoma
    bases because it can more easily enter Anterior chamber
  61. what was the purpose of topical trifluiridine for stromal keratitis in HEDS
    prevent epithelial keratitis
  62. what are diabetic changes to cornea
    "mild corneal hyposthesia, poor adherence of epithelium to stroma, delayed healing time with removal of epithelium"
  63. why shouldn’t you do phototherapeutic keratectomy (PTK) in band K
    calcium will ablate at a slower rate than cornea and will wind up with irregular astigmatism
  64. what is Rizzutti sign
    "in KC, shine penlight from temporal cornea and you see conical shape on nasal cornea"
  65. what systemic condition assocaited with mooren like PUK
    hep c
  66. how do you differentiate between moorens ucler and PUK
    PUK involves both cornea and sclera while mooren involves only cornea
  67. what are associated conditions of puk
    "RA (most common), hsv, vzv, tb, gonorrhea, syphillis, AIDS"
  68. what is treatmetn for mooren like PUK and what do you need to screen for?
    interferon therapy; screen for hep c
  69. what is ddz of K verticilata and what is most common cause
    "amiodarone (most common), chloroquine, hydroxychloroquine, chlorpromazine, subconj gentamycin, ibuprofen, indomethacin, naproxen, tamoxifen, Fabry disease"
  70. where is hyaline deposited in salzmann nodular degeneration
  71. what type of collagen is sclera
    "type I (mneumonic, the L in sclera is 1)"
  72. what type of collagen is associated with stromal wound healing
    type III
  73. what type of collagen is associated with basement membrane
    type 4 (mneumonic; four is the floor)
  74. what is the most common risk factor for fungal keratitis
    trauma with vegetable matter
  75. what can cause recurrent sch
    "diabetes, hypertension, bleeding diasthesis"
  76. what ophthalmic condition is associated with MEN IIB
    "enlarged corneal nerves occur in 100% of patients, ganglioneuromas occur in 95%; men IIB is medullary thyroid cancer, hyperparathyroidism, pheochromocytoma"
  77. what is treatment for candida and aspergillus keratitis
    " amphotericin B, although voriconazole is newer and can be given topically and orally (more expensive); use natamycin for fusarium infections"
  78. what fungal infection is most common in southern US
  79. what dystrophy is combo of lattice and granular corneal dystrophy and what stain do you use
    avellino; congo red and mason trichome
  80. "when do you get negative staining, and what conditions"
    area of interest projects above the tear film -> vzv pseudodendrites (collection of heaped cells while hsv is epi defect) and thygeson superficial punctate keratophaty
  81. "after chemical injury with limbal stem cell destruction, when should you wait to perform stem cell transplant"
    logner the better because inflammation can lead to cell death and poor prognosis
  82. how often is congenital syphillis present b/l in both eyes; acquired syphillis?
    80%; 40%
  83. why is endothelial rejection the most importnat rejection?
    endothelial cells cant replace themselves
  84. "what are the differences between keratoglobus, KC, and pellucid marginal degeneration"
    "thinning in keratoglobus is generalized with thinnest areas in periphery resulting in global overall corneal curvature; thinning in KC is paracentral and at the apex; in PMD, normal thickness peripherally with thinning in a band centripetal to this resulting in inferior thinning with protusion of the cornea above the thinnig; keratoglobus is also present at birth while other 2 present in puberty"
  85. what bacteria can prenetrate intact epithelium
    """No Hard or Soft Contact Lens""- neiserria gonorrhea, haemophilus aegyptus, shigella, corynebacterium diphtherae, listeria"
  86. where is the thinnest area of cornea
    1.5mm temporal to geographic center
  87. what is classic association with Mooren ulcer
    helminthic infections
  88. describe gelatinous drop like dystrophy
    "AR, defect in TACSTD2 gene-> diffuse supepithelial and stromal amyloid deposits -> recurrent erosions, recurrence in 100% of grafts"
  89. whats the most common cause of dacryoadenitis
  90. what is the origin of cells of oncocytoma (caruncle cystadenoma)
    ductal and acinar cells of main and accessory lacrimal glands
  91. what is terrens marginal degeneration
    "mneumonic: think T's (Thinning of the cornea at the Top [starts superiorly], presents in Thirties, perforation is rare, but treatmetn for perforation is Transplantation [crescent shaped lamellar]), thinng starts from superior and spreads circumferentially, epithelium remains intact and fine pannus transverses area of thinning with a line of lipid deposition at the end of pannus"
  92. what is the dioptric power of the cornea? What percent does it contribute to the eye? Average radius of curvature?
    43.25; 75%; 7.8mm
  93. avg thickness of corneal epithelium?
  94. what kind of cataract do you get with wilsons disease and why
    "sunflower cataract, deposition of copper in anterior capsule in petaloid configuration"
  95. "what happens to osmalrity, lactoferrin and lysozyme in DES?"
    "increased osmolarity, decreaed lactoferrin and lysozyme"
  96. what does fluorescein actually stain
    disruption of intercellular junctions
  97. what type of HSS is phlycetnulosis
    type 4
  98. what bacteria causes phlyctenulosis
    staph in developed countries; mycobacterium tuberculosis in developing
  99. "thin man with bowel resection presents with K melting, what do you think ok?"
    "vit A deficiency from poor lipid absorption, test for serum retinol-binding protein level"
  100. what is I-S value and what do you see in KC?
    "I-S values compare steepness of inferior cornea to superior cornea, I-S > 1.2 associated with KC"
  101. what is the tx for corneal hydrops
  102. what type of HSS is scleritis
    type 3; think scl3ritis
  103. what dystrophy has highest rate of recurrence in grafts
    reis-buckler > lattice > granular > macular (mneumonic: Rude Little Green Men keep coming back)
  104. which dystrophy has the youngest age of presentation
    macular (youngest) < lattice < granular (mneumonic: Might Like to Grow before getting K dystrophy)
  105. what cells make up mutton fat KPs? Small dot KPs? Punctate KPs
    macrophages; fibrin; neutrophils and lymphocytes
  106. what is the enzyme deficiency of fabrys
    alpha galacotosidase a
  107. "in sjogrens, lacrimal glands are infiltrated by what cells"
  108. where do you see cowdry type I bodies
    hsv and vzv
  109. where do you see halberstaedter-Prowazek bodies
  110. what's the least common dstrophies?
    macular > granular > lattice (My Gringo Lady is rare)
  111. what is associated with microphthalmos
    "dwarfism, trisomy 13, mental retardation"
  112. what's the difference between microophthalmos and nanophthalmos
    microphthlamos the eye is small and disorganzied globe; nanophthalmos eye is small but organized
  113. is kaposis sarcoma from proliferation of vascular endo/epithelium?
  114. what are complications of MMC
    "non healing corneal epi defects, infectious sclerokeratitis, scleral melt/necrosis"
  115. what should you do with palpebral nevi
    always excisional biopsy because nevi are rarely found in lids;
  116. what locations of nevi should you do excisional bx
    "palpebral conjunctiva, caruncle, tarsal conjunctiva, caruncle, plica seminlunaris, fornix"
  117. where do guttae appear initially in FED
  118. what threshold K thickness are you worried about poor prognosis after CE; ECC count?
    650; ECC < 1000
  119. what's the triad of bietti crystalline corneoreintal dystorphy
    "nycatlopia, corneal crystals in periphery, tapetoretinal dystrophy; secondary to defect in lipid metabolism"
  120. what type HSS is SJS
    3 (3 letters of SJS)
  121. what's the risk of glaucoma in ocular melanocytosis? Risk of uveal melanoma?
    10%; 1/400
  122. what type of HSS is OCP
  123. what's the most important suture in determing astigamatism in PKP
    second suture
  124. how many points on the cornea does keratometer use to estimate corneal power
  125. what are important factors about a corneal graft
    "death to cooling time (when body is cooled), death to preservation time (ideally <12-18 hours), ECC >20,000, donor infectious disease serology, age of donor from 2-70, tissue storage time should be as short as possible (<4days)"
  126. what is ecc at birth
  127. what fungus is the most destructive
  128. what is ddx of chronic follicular conjunctivitis
    "molluscum contagiousm, drug toxicity, chlamydia infection (trachoma or inclusion conjunctivitis- typically presents with large follicles on inferior palpebra)"
  129. how do you treat chlamydia inclusion conjunctivitis
    "azithromycin 1g x1, doxy 100 x 7 days, erythro 500 x 7 days"
  130. what are Ses of tetracyclines
    "staining of teeth, GI upset, birth defects, CI in children < 10 years old"
  131. what systemic disease is cogan's associated with? Mooren's ulcer? Superior limbic keratoconjunctivitis? Schnyder crystalline corneal dystrophy?
    "polyarteritis nodosa, hep C, autoimmune thyroid disease, hyperlipidemia"
  132. what underlying bacteria is cause of styes
    staph aureus
  133. what are styes
    external hordeolum
  134. in cogans what lab do you want to get and why
    "RPR, you want to rule out syphillic interstitial keratitis before starting steroids for cogans"
  135. what is the pathophysioloigic cause of superior limbal keratoconjunctivitis
    mechanical trauma of the upper eyelid on the superior limbal area
  136. what are findings of superior limbal KC
    "papillary reaction on palpebral conj, hypertrophy of superior conj, PEE, fine superior corneal pannus"
  137. what part of the cornea does UV radiation damage (from snowblindness or welding burn)
  138. what layer of the cornea is missing in a dellen
    "none, it's just thinning of epithelium and stroma"
  139. what does hyaluroindase do for lidocaine? Epinephrine? Sodium bicarb?
    helps disperse lidocaine; decreases elimination of lidocaine by constrictinv blood vessels; decreases pain
  140. what causes wavelike irregularity of the ocular surface emanating from the limbus upon fluorescein dye
    "LSCD, from conjunctivazation of the cornea"
  141. what is ddx for uniltaeral arcus? Arcus in a young person?
    contralateral carotid disease vs ocular hypotony; hyperlipoproteinemia
  142. what is associated with nanophthlamos
    "hyperopia, short axial length, angle closure glaucoma, strabismus"
  143. how much limbal stem cells do you need to properly replenish cornea
  144. how does HSV and VZV affect iris respectively
    HSV causes patchy iris atrophy while VZV causes sectoral
  145. what dystrophy and degeneration result in diamond shaped opacities with clear intervening spaces?
    central cloudy dystrophy of francois and posterior crocodile shagreen degeneration
  146. how does alkaptonuria present and how do you prevent arthropathy
    deposition of pigmented material near medial rectus and lateral rectus muscle insertions; vit C to prevent arthropathy
  147. what is reponsible for the majority of eyes refractive power
    air-tear interface
  148. what's the classic topographic pattern of pellucid marginal degeneration
    crab claw
  149. what should you give for chemical injuries and why
    "tetracycline and vit C- tetracycline bind intracellular calcium and prevent PMN degranulation which causes corneal thinning, vit C is a cofactor necessary for collagen synthesis"
  150. what conjunctival melanoma features have worst prognosis
    "arising de novo, not involving limbus, residual melanoma after surgical excision"
  151. what are filaments in filamentary keratitis? What do you treat? Is there a tear deficiency state?
    strands of epithelial cells with mucus core; 10% N-acetylcysteine; yes
  152. describe PPMD
    "AD disease, b/l, characterized by a cluster or linear arrangement of vesicles in the posterior cornea surrounded by gray haze, glaucoma in 10-15% of patients"
  153. what medium is best for fungal culture? AK? Neisseria?
    saboraud's agar; non-nutrient agar with e. coli overlay; thayer-martin
  154. what bacteria releases gas and causes foamy appearance of bitot spots from vit A deficiency
    corynebacterium xerosis
  155. what are characteristics of neurotrophic ulcers
    elevated rounded eptiheloial edges generally in inferonasal location; commonly associated with HSV and VZV
  156. what medication to treat wegeners
  157. is interstitial keratitis usually from acquired or congenital sypillis? How can you tell?
    congenital; rarely get IK from acquired syphillis and 60% is unilateral if acquired
  158. at what corneal thickness would MCE most likely occur
  159. how much ECC in 60 yo; cataract age patient?
    2500; 2250
  160. are epithelial erosions more frequent and severe in reis buckler or theil benke
    reis buckler
  161. what happens to bowmans layer in reis-buckler? Theil benke?
    bowman layer is disrupted and replaced with sheetlike connective tissue layer; bowmans replaced with fibrocellular material in saw tooth pattern
  162. what inheritance pattern is reis buckler
  163. "if you see extensive molluscum, what test should you get "
  164. what is the ddx for immunoglubulin overproduction resulting in crystals thorughout all layers of cornea
    "multiple myeloma, waldenstrom macroglubulinemia, benign monoclonal gammopathy"
  165. whats first line treatment for RCE 2/2 BMD? 2/2 trauma
    epithelial debridement; stromal micropuncture; phototherapeutic keratectomy is last resort because it causes hyperopic shift
  166. what are associations of posterior AMORPHOUS corneal dystrophy
    "flat and thin cornea, hyperopia, no association with glaucoma, AD, sheet like opacity in posterior cornea; minimal vision loss so PK rarely needed"
  167. what is definition of corneal vertex? Corneal apex? Are they the same thing?
    point located at the intersection of the line of fixation and the corneal surface; apex is highest point on the cornea; not the same
  168. what 2 dystorphy has intraepitheial microcysts? How are they different?
    "meesman and lisch ; meesman has diffuse evenly spaced cysts while lisch has broad, band-shaped, feathery lesions in a whorld pattern that are densely crowded together"
  169. what disease presents with granulomatous conjunctivitis with pre-auricular lymphadenopathy
    "parinaud's ocularglandular syndrome usually from cat scratch disease (other cuases include tularemia, sporotrichosis, tuberculosis, syphillis)"
  170. what are characterists of scleromalacia perforans
    "painless, no inflammation, rarely spontatneous perforates, usually rupture from minimal trauma"
  171. what is width of descements' membrane at birth? Adult?
    3-4 microns; 10-12 microns in adults
  172. what are the 2 bands of descemet's membrane and which one grows with age
    anterior banded zone which develops in utero and psoterior nonbanded zone that is deposited by endothelial cells throughout life
  173. what is the order of repair of the eye in globa rupture
    "limbus, cornea, sclera"
  174. limbal stem cells are in what layer of the limbal epithelium
    basal layer
  175. what is ddx for primary causes of LSCD
    "aniridia, ectodermal dysplasia, sclerocornea, KID syndrome, congential erythrokeratodermia"
  176. what is ddx for secondary causes of LSCD
    "alkali burns, SJS, ocular surgery, trachoma"
  177. what are main complications of hard and soft CL
    central epithelial edema in hard; micropannus of 1-2 mm
  178. what are the 3 sphingolipidoses
    "fabry disease, multiple sulfatase deficiency, generalized gangliosidosis"
  179. what is Meretoja syndrome
    "features lattice corneal dystorphy and systemic amylodosis, caused by mutation in gelsolin gene, autosomal dominant; other findings are masked facies, lagophthalmos, cranial and peripheral nerve palsies, loose skin"
  180. "in HEDS, what environmental factor was significantly associated with HSV"
  181. what is infectious crystalline keratopathy
    characterized by white crystalline opacities within the stroma and a relative paucity of inflammation -> usually 2/2 low virulent alpha-hemolytic strep species like strep viridians -> usually occurs in grafts or corneas treated crhonically with steroids
  182. when do seis occur with ekc
    7-14 days
  183. what is ddx for enlarged corneal nerves
    "neurofibromatosis, men type IIB, phytanic acid storage disorder (refsum disease), leprosy (hansen disease), AK, familial dysauttonomia (riley day)"
  184. what conditions cause corneal nerves to be more visible
    "KC, ichthyosis, fuchs corneal dystrophy, congenital glaucoma, corneal edema"
  185. where does corneal steepening occur in terren marginal degeneration
    90 degrees away
  186. what is the treatment for corneal microsporidosis
    topical fumagillin
  187. what type of stromal infiltrates are more characteristic of zoster than hsv?
    "nummular (coin shaped), you can also see rasied mucous epithelial patches occuring weeks after skin rash, sectoral iris atrophy"
  188. what is the pathophys of rce
    associated with upregulation of matrix metalloproteinases
  189. what is most common ocular manifestation of congenital rubella
    salt and pepper retinopathy
  190. what is the most common bug associated with infectious crystalline keratophathy
    strep viridians
  191. what was treatment regiment for stromal keratitis in HEDS
    PF q2 and trifluridine qid
  192. how do you treat PUK
    conjunctival recession moves the feeder blood vessels away from the peripheral cornea (source of immunologic mediators) which will help relieve the corneal inflammation; refer to rheum!
  193. what are signs of AK
    "ring sign, radial perineuritis, pain out of proportion to exam, pseudodendrites"
  194. below what ECC are you at risk for corneal edema?
  195. what degeneration has brown-gold circular deposits in superficial stroma that are secondary to age and UV exposure with elastotic degeneration
    spheroidal degeneration (labrador degeneration)
  196. what medication can deposit in the posterior cornea and anterior lens capsule
    chlorpromazine (thorazine) and thioridazine (mellaril)
  197. why do nanophthalmic eyes have complications with cataract sx
    inelastic sclera leads to choroidal detachments
  198. whats the most common cause of K ulcer in soft cl wearer
  199. what are nonseptate fungi
    "mucor, absidia, rhizopus"
  200. what are septate fungi
    """FACtS"" fusarium, aspergillus, curvularia"
  201. what are predisposing conditiosn for mucormycosis
    "usually poorly controlled hospitalized diabetic ketoacidosis, but also renal failure and gastroenteritis"
  202. what do you think of if you see black eschar-like crusting in the nose or hard palate
  203. what chlamydia subtyped associated with trachoma?
    serotypes A-C; think trAChoma