Corneal Transplantation Flashcards
Generally accepted cutoff for age of corneal donor?
> /= 24 months
Generally accepted cutoff for endothelial cell density of donor?
2000 cells/mm^2
What is the most commonly used preservative media for corneal donor tissue in the US?
Optisol-GS (G for Gentamycin, S for Streptomycin)
Which of the following are contraindications to corneal donor status? a. congenital rubella b. active encephalitis c. active endocarditis d. rabies e. Down syndrome f. active conjunctivitis g. leukemia h. active disseminated lymphoma I. incarceration in prison j. systemic malignancy k. HIV l. Hepatitis B m. Hepatitis C n. Reye syndrome o. Creutzfeldt-Jakob disease p. dementia of unknown cause q. prior refractive surgery
All are contraindications except:
e. Down syndrome is C/I in PK and ALK but not EK (DMEK and DSEK)
j. systemic malignancy is not C/I
q. prior refractive surgery may not disqualify a donor from EK
How do surgeons generally determine the size of the corneal button in PK?
0.25-0.50 mm larger in diameter than host corneal opening
Which suture is the most important in determining post-operative astigmatism in PK?
The second cardinal suture
What is the approximate suture depth for PK sutures?
90-95% corneal thickness
What is the most commonly used suture for PK?
10-0 nylon
POD#1 s/p PK and patient does not have D-folds. Diagnosis?
high IOP (flattens out d-folds)
Unremitting postoperative edema after PK: Diagnosis and management?
Primary donor endothelial failure. Wait 4 weeks to 2 months before considering re-graft
What is Urrets-Zavalia syndrome?
fixed, dilated pupil with sectoral iris atrophy after PK (possibly 2/2 parasympathetic denervation)
Management of loose or broken sutures after PK?
Immediate removal to prevent vascularization, infection, and graft rejection
