Lens and Cataract

Question 1

WAGR

Answer 1

Wilms Tumor
Aniridia
GU abnormal
Retardation

A/w sporadic aniridia (1/3)

A/w PAX6 mutation (also post embryotoxon, Peters, Axenfeld, and congenital cataract)

Aniridia high risk of glaucoma

Question 2

cloudy cornea at birth

Answer 2

STUMPED
Sclerocornea; Trauma
Ulcer; mucopolysaccharidosis
Peters; Endothelial(CHED)
Dermoid

Question 3

calculate cornea power for post refractive sx pt

Answer 3

-Historical method=Pre-op K + (Preop spherical equivalent - postop SE refraction)
-Contact Lens method
-Topography method
#Post myopic sx – overestimate cornea power – lead to hyperopic surprise
post hyperopic sx – under – myopic surprise

Question 4

Hypermature cataract –> Morgagnian cataract
Intumescent cataract
Cerulean cataract

Answer 4

Intumescent cataract- swelling inside cataract with abundant amount of water
Cerulean cataract-Bluish opacity, N.V.S. AD type congenital cataract

Question 5

trauma contusion cataract

Answer 5

Posterior star-like cat

Question 6

Peters anomaly

Answer 6

failure of lens vesicle properly separate from surface ectoderm

Question 7

pre-op stop coumadin or ASA/Plavix (clopedogrel) /Vit E

Answer 7

coumadin 3-5 days

ASA/clopedogrel / Vit E - 10 days

Question 8

SRK formula

Answer 8

P=A-2.5L-0.9K

Question 9

most common congenital cataract

Answer 9

lamellar

Question 10

lens dislocate: ectopia lentis

Marfan’s: 50-80% develop
Homocysteinuria

Answer 10

Marfan’s: superotempral; abn fibrillin; brittle zonule;

Homocysteinuria: inferonasal; retardation and tall; thromboembolic risk with general; low methionine and high cysteine diet, Vit 6 supplement

Question 11

Glaukomflecken

Answer 11

grey-white anti subcapsular opacity

Question 12

Forster-Fuchs spot

Answer 12

RPE hyperplasia with high myopia (response to CNV does not progress)

Question 13

AREDS2 change

Answer 13

add lutein + zeaxanthin, long chain polyunsaturated fatty acid (DHA and EPA), or both 
taking out beta carotene, lower zinc dose, or both
#Study suggest substitute beta carotene with lutein + zeaxanthin

Question 14

Highest MW?
alpha cystallin
betagamma
gamma

Answer 14

Alpha: Hight MW

betagamma: represent majority weight 55%
gamma: minority cystallin by weight

Question 15

The wait time for dropped nucleus in the vitreous without CME

Answer 15

3 weeks

Question 16

Vossius ring

Answer 16

trauma compress iris against lens, circular pig deposit

Question 17

phacolytic glaucoma
vs
phacoanaphylactic (phacoantigenic) uveitis

Answer 17

phacolytic glaucoma: lens material leak through capsule–macrophage–clog TM
vs
phacoanaphylactic (phacoantigenic) uveitis: bag violated causing inflammation

Question 18

obese, thick-neck pt
COPD pt
pt prone to Valsalva (full bladder, constipation):

Pos or Neg posterior pressure

Answer 18

Positive vitreous pressure – shallow AC

Question 19

most mitotically active lens epithelial cell

Answer 19

anterior pre-equatorial capsule

Question 20

How does Crystalens work?

Answer 20

by changing the position in the bag

Question 21

PSC cataract

Answer 21

Commonly a/w DM

Myotonic dystrophy develop PSC after “Christmas tree” cataract

Question 22

remnant of:

Bergmeister’s pupillae
Mittendorf’s dot
iris strand

Answer 22

B- hyaloid a. (connect optic disc to fetal lens)
M- tunica vasculosa lentis
I- anterior pupillary membrane

Question 23

photostress recovery time:

macular disease or ON?

Answer 23

Macular:

time require to see one line above pre-test vision. >30 sec abn

Question 24

Anti or post Lenticonus

with Alport’s

Answer 24

lenticonus more common of posterior and unilateral

when anterior and bilateral – Alport’s ( also a/w kidney dis) – also appears “oil droplet” by retroillumination

Question 25

"oil droplet" b/l cataract in pt of first few weeks of life

Answer 25

Galactosemia AS inherited inability covert galactose to glacose. MC also severe form- classic galactosemia by defect in Gal-1-PUT eliminate milk products -malnutrition, hepatomegaly, jaundice and retardation.

Question 26

Brown-McLean syndrome

Answer 26

peripheral circumferential edema starting from inferiorly without central invovle; 6-16 years following intracap cataract surgery. Central corneal guttata; punctate orange-brown pigment on endothelium underlining edematous cornea

Question 27

Restor multifocal lens work by?

Answer 27

diffraction and refraction

Question 28

What is: | Temporal (pseudophakic) dysphotopsia?

Answer 28

Positive: stars, flashes, streak of lights, halos Neg: shadow most common due to square-edge designed lens or of high index material 10-20% cataract surgery pt -reassurance; alphagan P or pilo; glasses with thicker frame; piggyback lens; nasal anterior lens capsule removal by Yag; reverse optic capture; IOL exchange PREVENTION: capsulorhexis rim overlaps lens edge; round-edge with lower index material; IOL well centered; optic-haptic junction horizontally oriented.

Question 29

TASS | Toxic Anterior Segment Syndrome

Answer 29

TASS 12-24 hr postop (mgmt: control inflammation and IOP) | Endophthalmitis 2-7 days

Question 30

Lens derives from what germ layer

Answer 30

ectoderm

Question 31

Fuchs' heterochromic iridocyclitis (FHIC) | a/w Amsler sign

Answer 31

FHIC is a type of chronic uveitis that is associated with long and fragile vessels that cross the angle and insert high in the angle. Because of their high insertion, they are frequently (25% of cases) nicked when entering the anterior chamber with a keratome, resulting in intra- or post-operative hyphemas. This is why a more anterioriy-placed phaco wound is recommended in these patients. "Amsler sign" is the term given for the bleeding that occurs secondary to nicking these blood vessels. Other key features of FHIC include: • typically unilateral • typically without severe pain or photophobia (unlike other forms of uveitis) • "stellate" (star-configuration) keratic precipitates (KP) that are evenly scattered across the endothelium (in contrast to other forms of uveitis where the KP are located more inferioriy); these KP are also small/medium-sized and white • iris heterochromia (involved blue eyes appear darker; involved brown eyes appear lighter) • lack of anterior or posterior synechiae • high incidence of posterior subcapsular cataract (75%) • dffficutt to control gjaucoma (i.e. if a FHIC eye has glaucoma, it usually requires surgical glaucoma treatment for adequate control) Lastly, unlike other forms of chronic iridocyclitis. It is not necessary to treat the inflammation in FHIC. This is because the inflammation is not typically associated with the usual uveitic complications (e.g. anterior/posterior synechiae, cystoid macular edema, severe eye pain/photophobia, etc). Most of the management of FHIC focuses on glaucoma screening/management and cataract removal.

Question 32

Germinative zone

Answer 32

which is pre-equatorial zone (post to ant cap) and reside cuboidal epi cells, move to equator where they begin to differentiate to lens fiber, complete at "bow region" (post-equatorial zone)

Question 33

lens energy production

Answer 33

-5% aerobic glycolysis pathway -78% anaerobic -5% HMP DM -- sorbital pathway

Question 34

Weill-Marchesani syndrome

Answer 34

microspherophakia (faulty development of 2nd lens fibers) causing pupillary block angle closure glaucoma -tx with cycloplegics (also PI) ``` syn: short stature, short and stubby fingers, broad hand w/ reduced joint mobility. Either isolate (AR) or a/w Peters, Marfan, Alport, Lowe or congenital rubella. ```