Femtosecond Laser-assisted Arcuate Incisions Versus Manual Arcuate Incisions Outcomes

This study is designed to compare the effectiveness of LenSx laser arcuate relaxing incisions vs. manual (blade) arcuate relaxing incisions in patients with low, but significant, levels of astigmatism.

Study Overview

• Status: Completed
• Conditions: Cataract
• Intervention / Treatment: Device: femtosecond laser system arcuate corneal incision; Other: Manual LRI

Detailed Description

This study is a comparative, prospective, randomized contralateral eye study of visual outcomes after LenSx laser arcuate relaxing incisions utilizing the Woodcock nomogram at 90% thickness vs. manual (blade) fixed keratome diamond knife at 600 microns for arcuate relaxing incisions utilizing the Donnenfeld nomogram. Subjects will be assessed pre-operatively and at 1 day, 1 month and 3 months post-operatively. Clinical evaluations will include measurement of visual acuity, manifest refraction and corneal astigmatism measurement with the Lenstar and slit lamp exam.

• Study Type: Interventional
• Enrollment (Actual): 41
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Georgia
    • Gainesville, Georgia, United States, 30501
      • Gainesville Eye Associates

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 40 years and older (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria

Subjects are eligible for the study if they meet the following criteria:

Note: Ocular criteria must be met in both eyes.

• are willing and able to understand and sign an informed consent;
• are willing and able to attend all study visits;
• are more than 40 years of age, of either gender and any race;
• are presenting for cataract surgery or refractive lens exchange with a desire to reduce astigmatism and will be implanted with a non-toric lens
• have good ocular health, with no pathology that compromises visual acuity (outside of residual refractive error and cataract)
• have 0.50 D to 1.75 D of regular corneal astigmatism
• have potential acuity of 20/25 or better
• Are scheduled to have a non-toric monofocal intraocular lens (IOL) (SN60WF) lens implanted in both eyes

Exclusion Criteria If any of the following exclusion criteria are applicable to the subject or either eye, the subject should not be enrolled in the study.

• Irregular astigmatism (e.g. keratoconus)
• Corneal pathology (e.g. scar, dystrophy, pterygium, moderate-to-severe dry eye)
• Monocular status (e.g. amblyopia)
• Previous radial keratotomy, corneal refractive surgery or other corneal surgery (e.g. corneal transplant, lamellar keratoplasty)
• Previous anterior or posterior chamber surgery (e.g., vitrectomy, laser iridotomy)
• Diabetic retinopathy
• Macular pathology (e.g. age-related macular degeneration, epiretinal membrane)
• History of retinal detachment
• Subjects who have an acute or chronic disease or illness that would confound the results of this investigation (e.g., immunocompromised, connective tissue disease, clinically significant atopic disease, diabetes, and any other such disease or illness), that are known to affect post-operative visual acuity.

Pregnancy has a known effect on the stability of refractions and visual acuity. As such, subjects who become pregnant during the study will not be discontinued but their data may be excluded from analyses of effectiveness.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: TREATMENT
• Allocation: RANDOMIZED
• Interventional Model: PARALLEL
• Masking: NONE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
ACTIVE_COMPARATOR: Femtosecond limbal relaxing incision (LRI); Eyes will be treated with arcuate incisions from a femtosecond laser system.	Device: femtosecond laser system arcuate corneal incision; Corneal arcuate incision made either with a blade (manual) or femtosecond laser system.; Other Names: LRI
ACTIVE_COMPARATOR: Manual LRI; Eyes will be treated with arcuate incisions completed manually with a blade.	Other: Manual LRI; Manual LRI

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Residual Refractive Astigmatism	Residual refractive astigmatism measured in diopters	3 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Spherical Equivalent Refraction	Spherical equivalent refraction in diopters	3 months
Eyes With Residual Refractive Astigmatism < 0.50 Diopters (D)	The number of eyes with residual refractive astigmatism < 0.50 diopters (D)	3 months
Uncorrected Monocular Distance Visual Acuity	Uncorrected monocular distance visual acuity in logMAR	3 months
Corneal Astigmatism	Anterior corneal astigmatism	3 months

Collaborators and Investigators

• Sponsor: Gainesville Eye Associates
• Collaborators: Science in Vision
• Investigators: Principal Investigator: Clayton G Blehm, MD, Gainesville Eye Associates

Study record dates

Study Major Dates

• Study Start (ACTUAL): October 15, 2019
• Primary Completion (ACTUAL): March 20, 2021
• Study Completion (ACTUAL): March 20, 2021

Study Registration Dates

• First Submitted: October 11, 2019
• First Submitted That Met QC Criteria: October 14, 2019
• First Posted (ACTUAL): October 15, 2019

Study Record Updates

• Last Update Posted (ACTUAL): September 5, 2021
• Last Update Submitted That Met QC Criteria: September 3, 2021
• Last Verified: February 1, 2021

More Information

Terms related to this study

• Keywords: astigmatism, limbal relaxing incisions
• Additional Relevant MeSH Terms: Eye Diseases; Wounds and Injuries; Lens Diseases; Cataract; Surgical Wound
• Other Study ID Numbers: CB-19-001

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: No