is the optical window to the eye
and must remain
to achieve excellent vision.
If corneal decompensation and
clouding results due to damage
to the Endothelium (En)
may be possible to bypass
traditional corneal transplant surgery
Stripping and Endothelial Keratoplasty)
or DMEK (Descemets
Membrane Endothelial Keratoplasty)
new surgical approaches to treating corneal pathology.
The most internal layer of the cornea
, the Endothelium (En)
of cells, is responsible for maintaining the clarity of the
entire cornea. The Endothelial monolayer
is attached to
Descemets Membrane (De).
If the Endothelium
the cornea will become edematous
, compromising acuity.
By removing the damaged Endothelium
(and the supporting Descemets Membrane) and replacing it with
healthy donor tissue (shown below as a blue
layer), the clarity to the cornea can be
restored more quickly and
without refractive power changes to the eye when compared to traditional
full thickness corneal transplant surgery.
DSEK requires an Artificial
Chamber and an Automated Microkeratome to prepare the
donor tissue (DMEK utilizes a simpler
method to harvest the tissue). The initial step in
DSEK begins with applying a
protective viscoelastic coating to the Artificial Chamber
as shown below:
The donor tissue, consisting of the cornea and some scleral rim, is transferred to the
A locking ring is then applied to the Artificial Chamber to secure
the donor tissue, followed by a second ring with a track.
The Automated Microkeratome is engaged in the track and activated,
traversing the donor and removing a thick
disk of corneal tissue. The donor tissue that remains is thinned
Next, the residual donor tissue which has been thinned is
trephined, resulting in an 8-9 mm disk of
Endothelial tissue (Endothelium, Descemets Membrane,
and a small section of Stroma) which will be implanted into the