Accuracy of LASIK Flaps Created With the LenSx® Femtosecond Laser - A Pilot Study

Not Applicable

Completed

Conditions: Myopia
Hyperopia

Interventions: Device: Femtosecond Laser System
Procedure: LASIK surgery

Registration Number: NCT02575911

Lead Sponsor: Alcon Research

Brief Summary: The purpose of this study is to evaluate the thickness accuracy of Laser-assisted in situ keratomileusis (LASIK) flaps created with the LenSx® Laser.

Detailed Description: Not available

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 34

Inclusion Criteria

Diagnosed with myopia or hyperopia and eligible for femtosecond laser initiated LASIK surgery;
Best corrected visual acuity (BCVA) correctable to at least 20/25 in each eye;
If contact lens wearer, willing to discontinue contact lens wear prior to screening procedures;
Willing and able to return for ALL scheduled follow-up examinations;
Willing and able to provide written informed consent;
Eligible for bilateral LASIK procedures to be done on the same day;
Other protocol-specified inclusion criteria may apply.

Exclusion Criteria

Previous corneal surgery, corneal lesions that will impede laser treatment, corneal edema, hypotony, glaucoma, existing corneal implant, or keratoconus;
Known sensitivity to planned study concomitant medications;
Participation in any other ophthalmic drug or device clinical study for 30 days prior to or during the time of participation in this study;
Irregular astigmatism, based on the Investigator's judgement;
Pregnant, lactating or planning to become pregnant during the course of the study;
Other protocol-specified exclusion criteria may apply.

Study & Design

Study Type: INTERVENTIONAL

Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
LenSx	LASIK surgery	LASIK surgery in both eyes using LenSx® Femtosecond Laser System
LenSx	Femtosecond Laser System	LASIK surgery in both eyes using LenSx® Femtosecond Laser System

Primary Outcome Measures

Name	Time	Method
Flap Thickness Accuracy Within the Central Zone at Month 3 Postoperative	Month 3 postoperative	Flap thickness was assessed by optical coherence tomography (OCT) and averaged from 3 separate scans. Flap thickness accuracy was defined as the mean difference between the achieved and desired (desired subtracted from achieved) flap thickness. A positive number represents a postoperative flap thickness that is thicker than the expected flap thickness and vice versa for a negative number. Each eye contributed separately to the analysis.

Secondary Outcome Measures

Name	Time	Method
Flap Thickness Precision Within the Central Zone at Month 1 and Month 3 Postoperative	Month 1, Month 3 postoperative	Flap thickness was assessed by OCT and averaged from 3 separate scans. Flap thickness precision (variability of the achieved flap thickness) was defined as the standard deviation of the flap thickness measurement. Each eye contributed separately to the analysis.
Ease of Flap Dissection at Day 0, Operative Day	Day 0, operative day	Ease of flap dissection (ease of lifting the flap during surgery) was assessed on a scale from 0 to 5 where 0 = Unable to lift flap and 5 = Able to lift flap without any resistance using blunt instrument. Each eye contributed separately to the analysis.
Stromal Bed Quality at Day 0, Operative Day	Day 0, operative day	Stromal bed quality was assessed by the investigator on a roughness scale from 0 to 5 where 0 = Very rough surface and 5 = Very smooth surface. Each eye contributed separately to the analysis.
Opaque Bubble Layer (OBL) at Day 0, Operative Day	Day 0, operative day	Opaque bubble layer was assessed by the investigator during the surgery on a scale from 0 to 5 where 0 = No OBL and 5 = 100% OBL in the stromal bed area. Each eye contributed separately to the analysis.
Best Corrected Distance Visual Acuity (BCDVA) by Visit	Baseline, Month 1, Month 3 postoperative	BCDVA (measurement with the participant's best spectacle correction) was assessed at a distance of 6 meters or 20 feet using a standard Snellen eye chart, both monocularly and binocularly, and reported categorically as a percentage of eyes analyzed.
Manifest Refraction Spherical Equivalent (MRSE)	Baseline, Month 1, Month 3 postoperative	The participant was manually refracted to his/her best correction using a phoropter and standard Snellen eye charts. Each eye contributed separately to the analysis.
Flap Thickness Accuracy Within the Central Zone at Month 1 Postoperative	Month 1 postoperative	Flap thickness was assessed by OCT and averaged from 3 separate scans. Flap thickness accuracy was defined as the mean difference between the achieved and desired (desired subtracted from achieved) flap thickness. A positive number represents a postoperative flap thickness that is thicker than the expected flap thickness and vice versa for a negative number. Each eye contributed separately to the analysis.
Uncorrected Distance Visual Acuity (UCDVA) at Month 1 and Month 3 Postoperative	Month 1, Month 3 postoperative	UCDVA (measurement of uncorrected (without spectacles or other visual corrective devices) distance visual acuity) was assessed at a distance of 6 meters or 20 feet using a standard Snellen eye chart, both monocularly and binocularly, and reported categorically as a percentage of eyes analyzed.
Prediction Error Between Target Versus Achieved Refraction at One and Three Months Post-op	Month 1, Month 3 postoperative	Prediction error was summarized as a percentage of eyes within 0.5 D and 1.0 D of target at one and three months postoperative