Keratoplasty

Question 1

DSAEK - postoperative shift

Answer 1

0.5-1.5D hyperopic shift

Question 2

DMEK - postoperative shift

Answer 2

hyperopic shift

Question 3

Postoperative shift in DSAEK/DMEK - reasons

Answer 3

1. Thinning of the cornea. 2. Change in posterior curvature of the cornea - adds “minus” power to the cornea

Question 4

Urrets-Zavalia syndrome

Answer 4

Fixed dilated pupil with sector iris atrophy after penetrating keratoplasty. Parasympathetic denervation of the iris sphincter. Or ischemic of the iris and acute rise in IOP

Question 5

Most common indication for penetrating keratoplasty

Answer 5

keratoconus

Question 6

DMEK + over DSAEK

Answer 6

lower rejection rate, smaller incision (2.8 mm) than DSAEK (5 mm), better vision

Question 7

DSAEK + over DMEK

Answer 7

easier to perform, recovery is faster, less rebubbling and primary failure

Question 8

DMEK - over DSAEK

Answer 8

more difficult to perform, recovery is longer, more rebubbling and primary failure

Question 9

DSAEK - over DMEK

Answer 9

higher rejection rate, larger incision DSAEK (5 mm) than DMEK (2.8 mm) , worse vision

Question 10

% in 2014

Answer 10

PK 42. ALK 2. EK 56 (DSAEK 50, DMEK 6)

Question 11

McCarey-Kaufman (MK) medium - storage time

Answer 11

4 days

Question 12

most commonly used intermediate-term storage medium

Answer 12

Optisol GS

Question 13

Optisol GS - storage time, what contains

Answer 13

up to 7 days. chondroitin 2.5%, dextran 1%, ascorbic acid, and vitamin B12; gentamicin, streptomycin

Question 14

Primary donor failure

Answer 14

edematous from the first postoperative day and remains so without inflammatory signs, a deficiency of donor endothelium should be suspected

Question 15

Primary donor failure - how long to wait for re-grafting

Answer 15

4 weeks and up to 2 months

Question 16

Wound misalignment or leak - when resuturing

Answer 16

shallow anterior chambers and low pressures lasting longer than 3 days

Question 17

PK - complications

Answer 17

Primary donor failure, Wound misalignment or leak, Flat chamber or iris incarceration in the wound, Endophthalmitis, Persistent epithelial defect, Elevated intraocular pressure, Recurrence of primary disease. Astigmatism, Late non–immune-mediated endothelial failure. Sutures: loosening, infectious abscesses, giant papillary conjunctivitis, vascularization

Question 18

Elevated intraocular pressure after PK - when

Answer 18

any time

Question 19

Elevated intraocular pressure after PK - first sign

Answer 19

loss of folds in the Descemet membrane

Question 20

Epithelial rejection

Answer 20

minority, early in the postoperative period (1–13 months), may be asymptomatic; however, blurred vision

Question 21

Subepithelial rejection

Answer 21

these may be asymptomatic or may cause glare or reduced vision. They resemble the infiltrates associated with adenoviral keratoconjunctivitis

Question 22

Stromal rejection

Answer 22

more commonly after DALK, It may present as stromal infiltrates, neovascularization, or, typically, noninflitrative keratolysis within the graft–host interface