Keratoconus, post-refractive surgery ectasia Eye Diseases Keratoconus
Conditions
Interventions
Patients will be recruited from the corneal clinics at Guy's and St Thomas' NHS Trust. All patients will have bilateral keratoconus or post-laser refractive surgery iatrogenic keratoconus. Patients wi
Sponsors
Guy's & St Thomas' Foundation NHS Trust (UK)
Eligibility
Sex/Gender
All
Inclusion criteria
Inclusion criteria: 1. Progressive keratoconus defined by an increase in refractive astigmatism, maximum keratometry, apex power of the cone by more than 1 diopter and/or a decrease in central corneal pachymetry by 10% in the preceding 2 years 2. Grade I-III keratoconus (3 mm keratometry less than 55 diopters, cone apex power less than 70 diopters, central pachymetry greater than 400 um) 3. Age over 18 years
Exclusion criteria
Exclusion criteria: 1. Advanced keratoconus (3 mm keratometry greater than 55 diopters, cone apex power greater than 70 diopters, central pachymetry less than 400 um) 2. Pregnancy 3. Corneal scarring 4. Co-existant ocular pathology other than keratoconus 5. Age less than 18 years
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| 1. Stability of refractive error (diopters) 2. Topographic simulated keratometry (diopters) (corneal curvature) 3. Corneal pachymetry (micrometers) 4. Visual acuity (logMar) at 12 months compared to pre-operative values These parameters will be measured pre-operatively and at 3, 6 and 12 months. | — |
Secondary
| Measure | Time frame |
|---|---|
| 1. Visual analogue pain scores documented for 5 days after surgery. Patients will be asked to grade the pain they are experiencing every 6 hours after surgery from 0 (no pain) to 10 (worse pain they have ever had) for 5 days following surgery 2. Complications if present will be documented at 1 week and 1, 3, 6 and 12 months after surgery | — |
Countries
United Kingdom
Outcome results
None listed