Devlin Corneal Transplant Flashcards
What’s the oldest and first procedure for the human transplant of solid tissues?
Penetrating Keratoplasy
How many layers does the PK transplant? What’s the success rate?
All of them
90%
How long does a PK transplant last?
100 yrs
What’s the main indication for PK?
Keratoconus due to Ectasia
What 3 things need to be checked in the pre-eval for PK?
- Visual potential
- Underlying Surface Disease
- HSV
What underlying disease is an absolute “no” for PK?
Aniridia/Stem Cell dysfunction
What does the normal graft look like 1-day post op for PK?
Clear, intact suturing, minimal or no epithelium
What 5 things do you look for after PK transplant?
- Flat AC
- Wound leak
- Very low IOP (<5)
- Broken/Loose sutures
- Infiltrates, infection (endophthalmitis)
What does primary injection from a corneal transplant look like?
Edema, clouding, painless
When does re-epithelization found post-op PK?
5-7days
When does a 2’ graft rejection occur? What are the sxs?
Occurs around 2 wks after transplant
Sudden onset of decreased vision, pain, uveitis
What type of suture?
Continuous suture, easier to perform, tedious to remove
Running
What type of suture?
Individual sutures, more difficult to maintain tension symmetry, easier to control astigmatism during removal
Interrupted
What layers does a Lamellar keratoplasty transplant?
Corneal tissues anterior to descemet’s membrane
What is the only layer of the host cornea saved?
Endothelium preserved
What are the 2 indications for LK?
- Keratoconus
2. Anterior scar secondary to trauma or infection
What are the 4 advantages of MDALK over PK?
- Lower rejection rate
- No “open sky” (dc risk of infection)
- Easier control of astigmatism/refraction
- Decreased healing time/Quicker recovery time
What are the 3 disadvantages of PK?
- Difficult to perform
- Potential interface haze/scar
- Not proven better visual result vs PK
What does DSEK stand for?
Descemet’s Stripping Endothelial Keratoplasty
What layers are removed in a DSEK?
Only remove endothelial cells and Descemet’s membrane
What are the indications for a DSEK?
- Fuch’s Dystrophy
- Surgical trauma, bullies keratopathy
- Failed PK
What is the key step in DSEK?
Air bubble is injected into AC to keep pressure on new graft to adhere to host
What are the advantages of DSEK over PK?
- 90%+ of cornea remains intact
- Excellent refractive outcome
- Recovery time ~ 1 month
What are the disadvantages of DSEK?
- Re-bubble rate is high
- Hyperopic shift ~ 2D
- AC trauma causes cataract
- IOP spike (>50mmHg)
T or F: DSEK rejection rate = PK rejection rate
True
What procedures is the Fentosecond laser used in?
- LASIK
- Cataract sx
- Softening of nucleus for Phaco
- MDALK dissection
- Graft button creation
What is the acceptable endothelial count for a donor corneal?
> 2700
What is the most difficult post-op battle with corneal transplants?
Rejection of donor cornea
What is the tx for a primary graft rejection?
Re-graft the cornea
When does immune mediated graft rejection occur?
4-6 wks and beyond
- can occur anytime for the life of the transplant
Epithelial graft rejections make up what % of graft rejections? What’s the tx for this?
10% of rejections
Replace donor epithelium by hosts epithelium
Though uncommon, when would a stromal rejection occur post-op? What reduces the chances of rejection?
~ 2 months
Host stromal cells replace donor’s over life of transplant
What % of graft rejections are endothelial? What ant. seg finding can be noted during SLE?
90% of true graft rejections
Khadadoust line
What is a khadadoust line a collection of?
Collection of WBCs forming a thing line across endothelium
How do you tx a severe of chronic rejection of a graft?
- q1h topical corticosteroid
- Oral prednisone
- Start with Medrol Dose Pak
How do you tx any pt after corneal transplant sx?
- Prednisolone Acetate 1% q2h
2. 4th Gen. FQ QID (Zymaxid, Moxeza, Besivance)
What are some clinical triggers of corneal transplants?
- Vascularization - large grafts close to Lim also region
2. Loose or broken sutures - remove immediately
What’s the most common cause of poor vision in a clear, compact graft?
Refractive management