Progressive Keratoconus
Conditions
Keywords
Keratoconus
Brief summary
Epi-keratoplasty Versus Collagen Cross-Linking in Progressive Keratoconus
Detailed description
Keratoconus is a bilateral corneal ecstatic disease which is not uncommon and always behaves progressively and results in visual impairment by inducing irregular astigmatism and corneal opacities. Collagen Cross-Linking (CXL) is widely used in progressive keratoconus. The cornea is soaked with a riboflavin solution and then being exposed to ultraviolet-A radiation. The performance creates links between collagen fibrils in order to rigidify the corneal stroma and slow down the progression of keratoconus. However, the effectiveness is not satisfied and accompanied with risks of side effects and serious complications, such as pain for the first two post-operative days, temporary loss of visual acuity during the first three months, infection and stromal opacity due to corneal scarring. Epi-keratoplasty is a reversible technique in which a corneal graft is transplanted on the recipients' eye with only removal of the epithelium of the receptor cornea. The procedure was assisted by femtosecond laser which allows precisely and neatly cutting. The graft strengths the whole host corneal rigidity and roughness and therefore renders the progression of keratoconus.
Interventions
PROCEDUREEpi-keratoplasty
Femtosecond laser assisted Epi-keratoplasty
PROCEDURECollagen Cross-Linking
Collagen Cross-Linking: Standard procedure, which is descriptor bellows: Corneal epithelium is mechanically removed. Then, a solution of riboflavin is instilled each minute for 30 minutes. Corneas are irradiated by a UVA light for 3mW/cm2 during 30 minutes
DEVICEFemtosecond laser
Use in the epic-keratoplasty surgery
Sponsors
Sun Yat-sen University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* diagnosis of Keratoconus * Age ≥ 18 years old * Corneal thickness ≥ 400 µm * Progressive stage 1 to 3 keratoconus (Krumeich classification)
Exclusion criteria
* Corneal thickness \< 400µm * Concomitant corneal disease * History of corneal surgery
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Changes of Spherical equivalent | 01012016~01012018: preoperatively, postoperatively 2 weeks, 1,2,3,6,12 months, 2 years |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| maximum keratometry (K-max) derived from computerized video keratography | 01012016~01012018: preoperatively, postoperatively 2 weeks, 1,2,3,6,12 months, 2 years | — |
| minimum keratometry | 01012016~01012018: preoperatively, postoperatively 2 weeks, 1,2,3,6,12 months, 2 years | also from computerized video keratography, the opposite description of K-max |
| Visual acuity | 01012016~01012018: preoperatively, postoperatively 2 weeks, 1,2,3,6,12 months, 2 years | — |
Other
| Measure | Time frame |
|---|---|
| Spherical equivalent | 01012016~01012018: preoperatively, postoperatively 2 weeks, 1,2,3,6,12 months, 2 years |
Countries
China
Contacts
Primary ContactXinbo Gao, MD, PHD
Outcome results
None listed