Cornea & Lens Mnemonic Flashcards
CHED and CHSD
CHED 1 you only need ONE allele, is the dominant version. Late onset since dominant
CHED 2 you need TWO alleles, is the recessive version. At birth/stationary
CHED - thick epi and stroma.
CHSD - normal epi/stroma, and ALL AD
Inheritance of cornea dystrophies
Corneal dystrophies - all AD except Macular - AR Gelatinous drop - AR Lisch - XR Bietti - cornearetinal dystrophy - AR
Band keratopathy
Causes of band keratopahy is CHIMPS:
C: calcium (hypercalcemia, vit D toxicity, sarcoidosis, milk-alkali syndrome, hyperparathyroidism)
H: hereditary (primary hereditary band keratopathy)
I: inflammation (chronic uveitis, interstitial keratitis, phthisis bulbi)
M: mercury exposure
P: phosphorus (elevated phosphorus with normal calcium as in renal failure)
S: silicone oil
Type of scleral collagen
The sclera is mostly made up of type I collagen and the proteoglycans, decorin, biglycan, and aggrecan. Type III collagen is associated with stromal wound healing. Type IV is associated with basement membranes (Descemet’s and lens capsule).
Mnemonic: Sclera is Type I collagen: the l in sclera is 1.
Fraser syndrome
“Frasier” –> as in Fraser syndrome
Fraser syndrome: crytophthalmos, micropenis/cyrtorchidism, possible malformations of ENT and kidneys.
Papillae vs follicles
PaP illae the “a” between the two “P”s reminds you of the central vascular tuft, and uPPer or suPerior lid
F O llicles the “O” reminds you of the white centre and surrounding dilated vessel, and lOwer lid or the “F” for inFerior lid or Fornix
Path findings in herpes
cow lips have herpes
cowdry lipschutz HSV and VZV
Bacteria that can penetrate intact epi
H and N Can Lyse whole Skin: Neisseria gonorrhea/meningitidis, Hamophilus aegytpus, Shigella, Cornybacterium diptheria and Listeria.
DDx enlarged cornea nerves
DDx for enlarged K nerves men(2)larged K nerves Men 2b NF2 Leprosy Acanthamoeba Refsum- accumulation of phytanic dz. Peripheral polyneuropathy, cerebellar ataxia, retinitis pigmentosa, and ichthyosis are the major clinical components.
Glaucoma (congenital)
Edema (of the cornea)
dysautonomia (Riley-Day)
Bigh3
BigH3 gene is located on Chromosome 5: Another name for Big is LARGE (5 letters therefore chr 5): L: Lattice (type 1) A: Avellino R: Reis-Bucklers G: Granular E(empty)
Posterior amorphous dystrophy
Don’t mistake posterior AMORPHOUS stromal dystrophy with posterior POLYMORPHOUS dystrophy (PPMD) which is assoc with glaucoma
I think of “posterior” pulling the cornea posteriorly leading to hyperopia (in posterior amorphous stromal dystrophy). Also, thin Corneas (approximately 380 um) with flat Ks (< 41 D).
Septate and non septate fungi
Nonseptate filamentous fungi includeMucor, Absidia, and Rhizopus. These fungi can causelife-threatening infections (“mucormycosis”)of the paranasal sinuses, brain, and orbit, typically inimmunocompromisedpatients.
Septatefungi include Fusarium, Aspergillus, and Curvularia. A nice mnemonic is:”F.A.C.t.s. “
Septate fungi are the most common cause of fungal keratitis
F = Fusarium
A = Aspergillus
C = Culvarium
P = Paecilomyces, Penicillium, Phialophora
Frequency, recurrence, occurrence of cornea dystrophies
“My Little Granny is the oldest”
Macular (youngest)
Lattice
Granular (oldest)
All increasing:
May Grow Lovingly… (lovingly = recurrence)
Man, Good Luck Finding… (finding = occurrence)
May Like Grandma… (grandma = age)
Most Common to Least Common: “Last Graft is Macular” Lattice–>Granular–>Macular
can also, think that Macular recurs the LEAST (and is AR).
Thanks for sharing the mnemonic. These might be helpful, too:
Mnemonic for the order of recurrence in grafts:
Rude Little Green Men keep coming back. (Reis-Bucklers > Lattice > Granular > Macular)
Mnemonic for relative prevalence of the dystrophies:
Get a Little More (Granular > Lattice > Macular)
Whorls in cornea
Mnemonic: Important FACTS IN identifying whorls in the corneal (corneal verticillata):
F: Fabrys
A: Amiodarone (m/c)
C: chloroquine (hydroxychloroquine)/chlopromazine
T: Tamoxifen
S: Subconjunctival gentamicin
I: Ibuprofen/ Indomethacin
N: Naproxen
Fabry diseaseis a sphingolipidoses. The three main sphingolipidoses are Fabry disease, multiple sulfatase deficiency, and generalized gangliosidosis. All have corneal verticilata. Fabry disease is inherited in an X-linked pattern and the others in a recessive fashion. Try to remember that Fabry and Hunter and both X-linked. This can be remembered by picturing a “fabulous” Hunter aiming a bow and arrow at a target shaped like an X. Fabry disease can also have renal failure and peripheral neuropathy. The most distinguishing clinical feature is that it has corneal verticillata. Tay-Sachs, another sphingolipidoses, typically has more retinal findings such as a cherry-red spot.
HZV infection of nerves
IN HZV infections: Frontal is most Frequently involved, Lacrimal is Least involved and Nasociliary when affected increases risk of corNeal Involvement.
Terrien’s
T: Thinning of the cornea
T: Top (superior)
T: Transversing pannus over area of thinning
T: Thirties
T: Treatment: Transplantation (cresent shaped lamellar) if perforation occurs
Terrien’s marginal degeneration is generally bilateral, but may be asymmetric. The corneastarts to thin superiorlyand the thinningspreads circumferentially. The epithelium remains intact and a finepannus traverses the area of corneal thinning. At the end of the pannus is a line oflipiddeposition.
This condition generally starts in the2nd or 3rd decade of lifeand is more common in males (3:1 males:females). The epithelium remaining intact distinguishes Terrien’s from other diseases such asMooren ulcer and PUK (peripheral ulcerative keratitis) which have loss of epithelium. Also, Terrien’s does not present with pain because there is no loss of epithelium.
Corneal steepening occurs 90 degrees away(i.e.against-the-rule astigmatismis induced). Perforation of the thinned cornea is rare. Crescent-shaped lamellar transplantation can be used if perforation
Chlamydia serotypes
Here is a summary of the serovars that are associated with the different Chlamydial diseases:
Trachoma: serovars A-C.
Adult and neonatal inclusion conjunctivitis: serovars D-K
lymphogranuloma venereum: L1-L3,
Some memorable mnemonics:
“trAChoma” –> serovars A-C
“DicK” - which references that adult/neonatal inclusion conjunctivitis are due to stds
Destruction of K stroma DDx
VAST CRIMES Viral (HSV) Autoimmune Staphylococcal marginal Terrien's/Furrow degeneration
Contact lenses Rosacea Infectious (bacterial, spirochetal TB) Mooren's ulcer Excise (excising cancerous growths around the limbus of the eye that might present in peripheral keratitis Sclerokeratitis
Collagen healing and meds
Accutane and Amiodarone (Cordarone) are associated with decreased corneal stromal healing.
Delayed epithelial healing has been associated with antihistamines, sumatriptan, and hormone replacement therapy.
CONTROVERSY IN OQ COMMMENTS
ReZoom
reZoom is used by ZeRo people because it is Refractive
Oblate/prolate corneas
With myopic LASIK, you “obliterate” the central cornea (you flatten it), leaving it oblate.
With hyperopic LASIK, you flatten the periphery, leaving the cornea protruding (steeper centrally), and prolate.
Microkeratome flat corneas
Flat corneas at risk for free flaps. Reduced amount of tissue protruding lop cornea straight off (free cap)
Lens crystallins
Alpha males = biggest but fewest in number, betas are small and the most common. Gamma are very small.
Beta-gamma crystallins divided into beta and gamma subgroups.
Alpha crystallins - largest of the crystallins. Represent only 1/3 of the lens proteins by mass.
Glands of the eye
Musky Moll Zlippery Zeis Watery Wolfring (and krause) also krause are at the "knee" of the conj Glands of Zeis are 'ze-baceous'
Interlenticular opacities
Acrylic - membrane - acrylic = AMA = against medical advice
Two acrylic lenses in the bag –> most likely to develop interlenticular opacities
Anterior Chamber Depth
Anterior Chamber Depth=ACD=3 letters therefore reminds us 3.0mm
Average anterior chamber depth (ACD) is approximately 3.0 mm with an average volume of 200 microliters
Average volume of the posterior chamber (i.e. the space posterior to the iris and anterior to the vitreous face) is 60 microliters. Both spaces are filled with aqueous humor. Volume of the vitreous cavity is 5-6 mL.
phakic intraocular lens placement; for example the “implantable collamer lens” (ICL): Patients whose ACD is under a certain threshold do not have enough room in the AC for an ICL. Placement of an ICL, in this instance, can lead to angle closure glaucoma.
Currently, the only FDA-approved ICL is the Visian ICL. Its requirements are an anterior chamber depth of at least 3.0 mm. Generally, this is not a problem because most ICL candidate patients are high myopes. High myopes typically have greater anterior chamber depths.
Differential for Acute Follicular Conjunctivitis:
Adeno Hardly Ever Happens to Careful Nuns Adenovirus Herpes EBV Hemorrhagic conjunctivitis Chlamydia adult inclusion conjunctivitis Newcastle’s
DDx chronic follicular conjunctivitis
Passing Tough Tests Mostly Means Late Cramming Parinaud’s Trachoma Toxins Molluscum Moraxella Lyme Chlamydia
Corneal Dystrophys
Marilyn Monroe Always Gets Her Man in LA County
Macular/ Mucopolysacchardie/ Alcian Blue
Granula/ Hyaline/ Masson trichrome
Lattice/ Amyloid/ Congo Red & Crystal Violet
Aspergillus vs. Mucor - which is septate
aSpergillus are Septate (45 degree angle branching)
Mucor has no S in it, so aren’t septate
GMS stain = most effective/classic stain for mucor. However H&E, periodic acid-Schiff, and calcofluor white may also be used to stain these organisms
Thiel Benhke and Reis Buckler
BBB = Buckler and Behnke affect Bowmans.
Masson trichrome
Red on blue, Masson trichrome is for you
Granular = hyaline = Masson trichrome
Lens dimensions
Adult lens measures 5 mm A-P diameter (3.5 at birth)
Learning cataracts is a 9 to 5 job (9 mm width, and 5 mm depth)
