Fuchs' Endothelial Dystrophy, Pseudophakic Bullous Keratopathy
Conditions
Brief summary
To evaluate the clinical outcomes (pos toperative best corrected visual acuity, endothelial count) and anatomical results (interface smoothness) of DSAEK with Femto LDV-prepared grafts from the endothelial side.
Detailed description
Corneal transplantation is the most frequently performed transplant surgery worldwide, restoring visual function when corneal damage is severe. Traditionally, Penetrating Keratoplasty (PKP) was used to treat all forms of corneal blindness, but it comes with potential complications such as graft rejection, wound leaks, and astigmatism. To address these limitations, Endothelial Keratoplasty (EK) emerged as a less invasive alternative, particularly for conditions where only the corneal endothelium is compromised (e.g., Fuch's endothelial dystrophy and pseudophakic bullous keratopathy). EK began with Posterior Lamellar Keratoplasty (PLK) and evolved through Descemet's Stripping Endothelial Keratoplasty (DSEK) and Descemet's Stripping Automated Endothelial Keratoplasty (DSAEK), which uses a microkeratome to create a thin corneal graft. DSAEK, however, results in a meniscus-shaped graft with some degree of hyperopic shift postoperatively. Another advancement, Descemet's Membrane Endothelial Keratoplasty (DMEK), uses only the donor's Descemet membrane and endothelium, providing better visual outcomes and fewer rejection risks. Despite these benefits, DMEK is technically challenging and unsuitable for some complex cases. Ultrathin (UT) DSAEK introduced sequential microkeratome cuts, achieving graft thickness below 100 µm. This approach offers faster visual recovery and comparable refractive outcomes to DMEK, but with higher perforation risks during graft preparation. Newer graft preparation methods, such as femtosecond laser-assisted techniques, have been introduced to improve consistency, though deeper femtosecond laser cuts sometimes reduce accuracy due to laser scattering. This study proposes using Femto LDV (Ziemer Ophthalmic Systems AG) to prepare ultrathin DSAEK grafts from the endothelial side to ensure smoother interfaces and consistent graft thickness. Previous in-vitro studies indicate that these grafts offer better endothelial protection and less damage when coated with Viscoat (sodium chondroitin sulfate 4.0%-sodium hyaluronate 3.0%) compared to basic saline solution. Study Aim The goal of this pilot study is to evaluate the clinical outcomes (best-corrected visual acuity, endothelial cell count) and anatomical outcomes (interface smoothness) of DSAEK with Femto LDV-prepared grafts.
Interventions
PROCEDUREEndothelial Side Up Femtosecond Laser Assisted DSAEK
The Femto LDV Z8 laser system will be set to create a 100 μm thick graft with a 7.5 mm diameter. The graft will be inverted, placed endothelial side up in the anterior chamber, and coated with Viscoat. A fixation ring will center the graft by holding the scleral rim with forceps. After cutting, the cornea should remain endothelium-up, stained with Trypan Blue, and dissected using a blunt spatula. The graft will be placed on a Busin glide and coated with Viscoat. A 3-4 mm corneal incision will be made, and Descemet's membrane will be marked and stripped. The graft will be inserted using the Busin glide, spreading automatically. A small air bubble will fill the anterior chamber to compress the graft for 10 minutes.
Sponsors
Dar El Oyoun Hospital
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Healthy volunteers
No
Inclusion criteria
Patients with Fuchs' endothelial dystrophy Patients with bullous keratopathy secondary to intraocular surgeries, iridocorneal endothelial syndrome, or viral keratitis
Exclusion criteria
Bullous keratopathy secondary to glaucoma or ocular trauma Corneal stromal scarring or opacities Diseases not affecting the corneal endothelium, including corneal ectasia (e.g., keratoconus, keratoglobus, pellucid marginal degeneration) Epithelial, Bowman layer/anterior stromal, and stromal dystrophies Hypotonic eyes Retinal diseases Any type of optic atrophy
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Best spectacle-corrected visual acuity | after 3 and 6 months | Measurement Tool: Snellen chart Unit of Measure: LogMAR |
| Endothelial cell count using specular microscopy | after 3 and 6 months | Measurement Tool: Specular microscopy Time Frame: After 3 months and 6 months |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Total central corneal thickness (CCT) | after 3 and 6 months | Measurement Tool: Anterior Segment Optical Coherence Tomography (AS-OCT) Unit of Measure: Micrometers (µm) |
| Donor Corneal Endothelial Thickness (CET) | After 3 months and 6 months | Measurement Tool: Anterior Segment Optical Coherence Tomography (AS-OCT) Unit of Measure: Micrometers (µm) |
Countries
Egypt
Contacts
Primary ContactTarek H Nasr, Msc
Outcome results
None listed