Corneal Astigmatism
Conditions
Keywords
astigmatism
Brief summary
To determine if arcuate incisions performed with the iFS femtosecond laser are safe and effective in reducing corneal astigmatism.
Detailed description
Surgeons will perform arcuate incisions in the cornea in arc segment patterns using the iFS femtosecond laser to treat subjects with corneal astigmatism.
Interventions
DEVICEiFS Femtosecond Laser System
arcuate incisions placed with the iFS femtosecond laser
Sponsors
Abbott Medical Optics
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
21 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
1. Male or female, of any race, and at least 21 years of age at the time of pre-op exam 2. Corneal astigmatism, as determined by topographic keratometry, of 0.75 D to 4.00 diopters (D) 3. Best Spectacle Corrected Distance Visual Acuity (BSCVA) 1. Group 1: * Natural astigmatism, no cataract - BSCVA of 20/25 or better * Pre cataract or phakic IOL surgery - no BSCVA criteria 2. Group 2: * Post IOL surgery- BSCVA of 20/25 or better 4. Uncorrected Visual Acuity (UCVA) of 20/40 or worse 5. Demonstration of agreement: Corneal astigmatism (as determined by topographic keratometry) must be in agreement with refractive astigmatism (as determined by manifest refractions) within \</= 0.75 D in magnitude and 15 degrees axis when cylinder \</= 1.5 D or 10 degrees axis when cylinder \> 1.5 D. 6. Preoperative central pachymetry of \>/=480 um 7. Keratometry between 38.0 D (flat) to 48.0 D (steep) 8. Corneal power (diopters) difference at the 3mm point from topographic center shall be \</= 1D at the steepest meridian 9. Intraocular pressure of 12 to 21 mm Hg with no glaucomatous retinal/optic nerve changes 10. Subjects who have worn a contact lens within the past 30 days must remove the soft lens at least 2 weeks prior and a rigid or toric lens at least 3 weeks prior to baseline measurements 11. Willing and capable of returning for follow-up examinations for the duration of the study
Exclusion criteria
1. Angle kappa of greater than 0.5 mm, absolute value 2. Prior implantation of toric or multifocal intraocular lens 3. Women who are pregnant, breast-feeding, or intend to become pregnant over the course of the study 4. Concurrent use of topical or systemic medications that may impair corneal wound healing 5. History of any ocular or medical conditions that could affect corneal wound healing 6. History of active or recurrent ophthalmic disease, including corneal dystrophy or other non-refractive abnormality such as exposure keratitis or clinically significant dry eye 7. Abnormal topography, including evidence of keratoconus or pellucid marginal degeneration in either eye 8. Evidence of clinically significant corneal opacity/scar in the operative eye(s) within an 8 mm diameter zone of the visual axis 9. Known sensitivity or inappropriate responsiveness to any of the medications used in the post-operative course 10. Participation in any other conflicting clinical study
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Reduction of Astigmatism | 6 months | Reduction of astigmatism as determined by manifest refractive cylinder |
Secondary
| Measure | Time frame |
|---|---|
| Percent of Eyes With Loss of ≥ 2 Lines of Best Spectacle Corrected Visual Acuity (BSCVA) | 6 months |
Countries
Austria, France, Germany
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Natural Astigmatism Use of the iFS Femtosecond Laser System to make arcuate incisions to correct naturally occurring corneal astigmatism in eyes with no prior history of ophthalmic surgery. May include eyes with cataracts. | 34 |
| Post Cataract With Residual Astigmatism Use of the iFS Femtosecond Laser System to make arcuate incisions to correct residual astigmatism in eyes that have undergone cataract extraction. May also include eyes with residual astigmatism following implantation of a phakic intraocular lens implanted. | 6 |
| Total | 40 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Lost to Follow-up | 2 | 1 |
| Overall Study | Withdrawal by Subject | 1 | 0 |
Baseline characteristics
| Characteristic | Natural Astigmatism | Post Cataract With Residual Astigmatism | Total |
|---|---|---|---|
| Age, Continuous | 52.4 years STANDARD_DEVIATION 16.6 | 55.0 years STANDARD_DEVIATION 15.9 | 53.7 years STANDARD_DEVIATION 16.6 |
| Region of Enrollment Austria | 17 paticipants | 2 paticipants | 19 paticipants |
| Region of Enrollment France | 0 paticipants | 1 paticipants | 1 paticipants |
| Region of Enrollment Germany | 17 paticipants | 3 paticipants | 20 paticipants |
| Sex: Female, Male Female | 26 Participants | 5 Participants | 31 Participants |
| Sex: Female, Male Male | 8 Participants | 1 Participants | 9 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 1 / 34 | 1 / 6 |
| serious Total, serious adverse events | 1 / 34 | 1 / 6 |
Outcome results
Primary
Reduction of Astigmatism
Reduction of astigmatism as determined by manifest refractive cylinder
Time frame: 6 months
Population: Data analysis was performed for eyes treated. Subjects may have had one or both eyes treated. If both eyes, one eye may have been in Natural Astigmatism group and the other eye in the Post Cataract with Residual Astigmatism group.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Natural Astigmatism | Reduction of Astigmatism | -0.75 diopter | Standard Deviation 0.94 |
| Post Cataract With Residual Astigmatism | Reduction of Astigmatism | -0.88 diopter | Standard Deviation 0.26 |
Secondary
Percent of Eyes With Loss of ≥ 2 Lines of Best Spectacle Corrected Visual Acuity (BSCVA)
Time frame: 6 months
Population: Data analysis was performed for eyes treated. Subjects may have had one or both eyes treated. If both eyes, one eye may have been in Natural Astigmatism group and the other eye in the Post Cataract with Residual Astigmatism group.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Natural Astigmatism | Percent of Eyes With Loss of ≥ 2 Lines of Best Spectacle Corrected Visual Acuity (BSCVA) | 4.9 percentage of eyes |
| Post Cataract With Residual Astigmatism | Percent of Eyes With Loss of ≥ 2 Lines of Best Spectacle Corrected Visual Acuity (BSCVA) | 0 percentage of eyes |