Descemet’s Stripping Automated Endothelial
Keratoplasty (DSAEK)
The cornea, the transparent front "window of the
eye", is responsible for about two thirds of the
focusing power of the eye. The cornea's refractive
power is actually greater than that of the eye's lens.
The cornea receives its nutrients through the tear
film. A normal, healthy cornea should be
transparent, thus devoid of blood vessels and opacities.
Corneal tissue can become damaged through disease or
trauma. This damage can cause scar tissue and
opacities in the normally-clear cornea, resulting in a
reduction in visual acuity.
If the cornea develops visually significant opacities
or irregularities, a
corneal transplant, or DSAEK
procedure can be performed.
What is DSAEK
Descemet's stripping automated endothelial
keratoplasty (DSAEK) involves surgically replacing
diseased cornea tissue with donor cornea tissue.
Instead of the entire cornea being removed and replaced,
only the damaged layer of tissue is replaced, making
DSAEK a much less invasive option than the traditional
method of total corneal transplantation.
This less invasive procedure leads to rapid
recoveries and reduces the risks of sight threatening
complications like hemorrhaging, infection and wound
rupture.
Who is a candidate?
DSAEK is a preferred surgical procedure over corneal
transplant, but it is not for everyone. Only those
corneas with defects and damage limited to the inner
cornea layer (endothelium) are candidates for DSAEK.
Eyes with corneal scars are not good candidates for
DSAEK and will be considered for full corneal transplant
surgery.
A common disease that can cause damage to this inner
layer of the cornea is Fuchs' Corneal Dystrophy.
This inherited eye disease causes the cornea to swell, opacify and distort vision.
The surgical procedure
DSAEK is an outpatient procedure. No
hospitalization is required. The entire surgery,
including prepping the eye, usually takes between 45 and
60 minutes.
After the eye is cleaned and prepared with a sterile
drape, a small incision is made at the edge of the
cornea. Through this tiny incision, the diseased
inner layer of cornea is peeled away and removed.
The donor cornea's inner layer is separated from the
other layers with a precision machine called a
microkeratome. This ultra-thin "button" of cornea
is then carefully folded and inserted into the eye
through the incision and attached to the back, inner
"dome" of the cornea. The donor tissue is then
held in place with an air bubble until it adheres to its
new place in the patient,s eye, usually in about 24
hours.
The small incision is then secured with one small
suture.
Recovery time
In most cases, the vision will begin to improve in
about one week. Full recovery is typically 3
months.
What are the differences between DSAEK and
Corneal Transplant
| |
|
Penetrating Keratoplasty
(full thickness traditional cornea transplant) |
|
DSAEK
(partial thickness posterior cornea transplant) |
| Typical time for visual
improvement |
|
6-12
months |
|
4-6 weeks |
| Visits for suture
adjustment |
|
6-12
visits |
|
2-3 visits |
| Time of surgery |
|
45-60
mins. |
|
45-60 mins. |
| Wound size |
|
7.5 mm
diameter circle |
|
5 mm linear |
| Sutures |
|
16 |
|
2-4 |
| Contact lens
required |
|
Rigid
gas permeable (often) |
|
Not required |
| Induced
astigmatism |
|
High regular and
Irregular
astigmatism possible |
|
Minimal to no induced
astigmatism |
| Indications for surgery |
|
Cornea
scar, keratoconus,
pellucid marginal degeneration, corneal ulcer |
|
Fuch's endothelial dystrophy,
cornea edema, pseudophakic bullous keratopathy |
Related links:
Corneal Transplant
|