Astigmatism, Cataract
Conditions
Keywords
Astigmatism, Cataract, Femtosecond laser
Brief summary
A cataract is a clouding of the lens that occurs naturally with age. Cataract surgery involves removal of the cloudy lens and replacement with an artificial one. A special laser (femtosecond laser) is now being used to help make cataract surgery safer and more accurate . The femtosecond laser can also be used to correct astigmatism, an irregular curvature of the cornea, at the time of cataract surgery through a procedure called astigmatic keratotomy (AK). This study is gathering information about the specific laser settings that are used to perform astigmatic keratotomies (AK) during cataract surgery. This information will be used to improve the outcomes of patients that receive cataract surgery with astigmatic keratotomies in the future.
Interventions
DEVICEFemto-AK
Astigmatic Keratotomy / Arcuate Incisions for the correction of astigmatism
Sponsors
Milton S. Hershey Medical Center
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Intervention model description
This is a prospective, single-center, single-arm, interventional clinical trial. Subjects that meet inclusion and exclusion criteria are invited to participate.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Age: ≥18 years of age * Sex: male or female * Patients who are planned to undergo femtosecond laser-assisted cataract surgery with astigmatic keratotomy at the Schein Ernst Mishra Eye clinic within the next 60 days of their cataract consultation visit. Subjects with planned single or bilateral cataract eye surgeries are eligible. Planned opposite eye surgery must be within 2-4 weeks of first cataract surgery. * Fluent in written and spoken English
Exclusion criteria
* Patients with corneal dystrophies, including anterior basement membrane dystrophy, keratoconus, and Fuch's endothelial corneal dystrophy. * Age \< 18 years * Pregnant women * Cognitive impairment * Prisoners
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Keratometric Correction Index | 1 month | Keratometric Correction index is the ratio of surgically induced astigmatism to target induced astigmatism. A correction index of 1 suggests that the actual surgically induced astigmatism, as measured by pre- vs- post-op reflectance keratometry, perfectly matched the target (anticipated) induced astigmatism. Correction indices below 1 suggest an under-correction while values above 1 suggest an over-correction. |
| Refractive Correction Index | 1 month | Refractive Correction index is the ratio of surgically induced astigmatism to net effective astigmatism. A correction index of 1 suggests that the actual surgically induced astigmatism, as measured by pre- vs- post-op manifest refraction, perfectly matched the effective astigmatism as estimated by the nomogram. Correction indices below 1 suggest an under-correction while values above 1 suggest an over-correction. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| All Participants Who Completed the Study Ages of all participants | 69 |
| Total | 69 |
Baseline characteristics
| Characteristic | All Participants Who Completed the Study | — |
|---|---|---|
| Age, Categorical <=18 years | 0 Participants | — |
| Age, Categorical >=65 years | 57 Participants | — |
| Age, Categorical Between 18 and 65 years | 12 Participants | — |
| Age, Continuous | 73.3734 years | — |
| Race and Ethnicity Not Collected | — | — Participants |
| Region of Enrollment United States | 69 participants | — |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | 0 / 0 |
| other Total, other adverse events | 0 / 0 |
| serious Total, serious adverse events | 0 / 0 |
Outcome results
Primary
Keratometric Correction Index
Keratometric Correction index is the ratio of surgically induced astigmatism to target induced astigmatism. A correction index of 1 suggests that the actual surgically induced astigmatism, as measured by pre- vs- post-op reflectance keratometry, perfectly matched the target (anticipated) induced astigmatism. Correction indices below 1 suggest an under-correction while values above 1 suggest an over-correction.
Time frame: 1 month
Population: patients underwent cataract extraction with AKs and insertion of a non-toric intraocular lens.
| Arm | Measure | Value (MEAN) |
|---|---|---|
| Astigmatic Eyes | Keratometric Correction Index | 0.51 index |
Primary
Refractive Correction Index
Refractive Correction index is the ratio of surgically induced astigmatism to net effective astigmatism. A correction index of 1 suggests that the actual surgically induced astigmatism, as measured by pre- vs- post-op manifest refraction, perfectly matched the effective astigmatism as estimated by the nomogram. Correction indices below 1 suggest an under-correction while values above 1 suggest an over-correction.
Time frame: 1 month
| Arm | Measure | Value (MEAN) |
|---|---|---|
| Astigmatic Eyes | Refractive Correction Index | 0.91 index |