Status:
COMPLETED
Study of the MEL 80 Excimer Laser Using LASIK in the Treatment of Mixed Astigmatism
Lead Sponsor:
Carl Zeiss Meditec, Inc.
Conditions:
Mixed Astigmatism
Eligibility:
All Genders
18+ years
Phase:
NA
Brief Summary
The purpose of this study is to determine whether the MEL 80 Excimer Laser is effective in the treatment of mixed astigmatism up to 6.0 D, when used as part of the Laser In Situ Keratomileusis (LASIK)...
Detailed Description
LASIK has become one of the most common refractive eye procedures performed in the country. In the mixed astigmatism procedure, a combination of both a steepening (hyperopic treatment) and a flattenin...
Eligibility Criteria
Inclusion
- Naturally occurring mixed astigmatism when the magnitude of cylinder (up to 6.0 D) is greater than the magnitude of sphere, and the cylinder and sphere have opposite signs, at the spectacle plane;
- Have a stable refraction for at least the past twelve months, as demonstrated by a change of less than or equal to 0.50 D preoperative spherical equivalent shift over twelve months prior to surgery;
- Discontinue use of contact lenses at least 2 weeks for hard contacts and 3 days for soft lenses prior to the preoperative examination;
- Hard contact lens wearers must have two central keratometry readings and two manifest refractions taken at least one week apart that do not differ by more than 0.50 D
- Have visual acuity correctable to at least 20/40 in both eyes
- Have no more than 0.75 D of latent hyperopia as determined by the difference between the preoperative manifest refractive spherical equivalent (MRSE) and cycloplegic refractive spherical equivalent (CRSE);
- Be at least 18 years of age
- Corneal topography should be normal;
- The operative eye must be targeted for emmetropia;
- Be willing and able to return for scheduled follow-up examinations for twelve months after surgery;
- and provide written informed consent.
Exclusion
- History of anterior segment pathology, including cataracts (in the operative eye);
- Clinically significant dry eye syndrome unresolved by treatment;
- Residual, recurrent, active ocular or uncontrolled eyelid disease, corneal scars within the ablation zone or other corneal abnormality such as recurrent corneal erosion or severe basement membrane disease;
- Ophthalmoscopic signs of keratoconus (or keratoconus suspect);
- Required ablation is deeper than 250 microns from the corneal endothelium;
- Irregular or unstable (distorted/not clear) corneal mires on central keratometry readings;
- Blind in the fellow eye;
- Previous intraocular or corneal surgery of any kind in the operative eye(s), including any type of surgery for either refractive or therapeutic purposes;
- History of ocular Herpes zoster or Herpes simplex keratitis;
- History of steroid-responsive rise in intraocular pressure, glaucoma, or preoperative IOP \>21 mm Hg;
- Diabetes, diagnosed autoimmune disease, connective tissue disease or clinically significant atopic syndrome;
- Immunocompromised patients, or use of chronic systemic corticosteroid or other immunosuppressive therapy;
- Pregnant, lactating, or child-bearing potential and not practicing a medically approved method of birth control;
- Sensitivity to planned study medications;
- Simultaneous participation in other ophthalmic drug or device clinical trial.
- For Fellow (Second) Eyes in Simultaneous Bilateral Treatment Procedures
- 1\. Flap complications during the first eye's surgery such as a free cap, partial flap, thin flap, or irregular flap.
- 2\. Epithelial defect exceeding 2 mm x 2 mm in dimension, or clinically significant debris in the interface between the flap and underlying stroma for the first eye.
- 3\. Severe blepharospasm in the first eye that may have prevented or impeded the completion of the keratectomy and/or the laser ablation procedure.
- 4\. Poor subject cooperation with instructions for the first eye's surgery and/or poor subject fixation on the laser fixation target.
- 5\. Aborted LASIK procedure in the first eye or PRK was performed in the first eye because LASIK was not possible.
Key Trial Info
Start Date :
January 1 2007
Trial Type :
INTERVENTIONAL
Allocation :
ACTUAL
End Date :
December 1 2009
Estimated Enrollment :
126 Patients enrolled
Trial Details
Trial ID
NCT00761826
Start Date
January 1 2007
End Date
December 1 2009
Last Update
July 19 2018
Active Locations (5)
Enter a location and click search to find clinical trials sorted by distance.
1
US Navy Refractive Surgery Center
San Diego, California, United States, 92106
2
Dishler Laser Institute
Greenwood Village, Colorado, United States, 80111
3
Discover Vision Centers
Kansas City, Missouri, United States, 64055
4
Fine, Hoffman, and Packer
Eugene, Oregon, United States, 97401