NCT00803478

Brief Summary

Corneal sensation is known to play a role in tear secretion. Decreased sensation leads to decreased tear production; and when bilateral, leads to a decreased blink rate as well. Dry eyes are a common side effect of LASIK. Incidence rates vary widely, but have been reported in as many as 59% of patients. And almost all patients have some transient dry eye symptoms immediately following LASIK. Previous studies have looked at the effect of hinge position (superior vs. nasal) and hinge width on corneal sensation and dry eye after LASIK performed with a mechanical microkeratome. Corneal sensation was decreased and dry eye signs and symptoms increased immediately following LASIK in all eyes. These parameters then improved at all time periods between 1 week and 6 months post-operative. Loss of corneal sensation and dry eye signs and symptoms were greater in eyes with superior-hinge flap than nasal-hinge flap, and in eyes with narrower hinge flap rather than wider hinge flap IntraLase LASIK, using the IntraLase femtosecond laser rather than a mechanical microkeratome to cut the corneal flap, has become an increasingly popular procedure. It provides several advantages over mechanical microkeratomes, including reduced surgical complications, more predictable flap thickness, better astigmatic neutrality, decreased epithelial injury, and an ability to operate on a wider range of patients. The investigators propose this study to evaluate the effect of flap hinge size and flap thickness in corneal flaps created with the IntraLase laser. The investigators would like to determine if there is a difference from the previously discussed results found when using the mechanical microkeratome. Also, with the increased ease of programming alternate hinge width or flap thickness with IntraLase, if the investigators find a significant difference with an alternate flap configuration, it might translate to a feasible change in clinical practice.

Trial Health

30
At Risk

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Trial has exceeded expected completion date
Timeline
Completed

Started Jun 2004

Longer than P75 for not_applicable

Geographic Reach
1 country

1 active site

Status
withdrawn

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

Study Start

First participant enrolled

June 1, 2004

Completed
4.3 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

September 1, 2008

Completed
3 months until next milestone

First Submitted

Initial submission to the registry

December 4, 2008

Completed
1 day until next milestone

First Posted

Study publicly available on registry

December 5, 2008

Completed
7 years until next milestone

Study Completion

Last participant's last visit for all outcomes

December 1, 2015

Completed
Last Updated

February 3, 2016

Status Verified

February 1, 2016

Enrollment Period

4.3 years

First QC Date

December 4, 2008

Last Update Submit

February 1, 2016

Conditions

Keywords

IntraLase LASIK for primary myopia

Outcome Measures

Primary Outcomes (1)

  • To evaluate the effect of hinge position (superior vs. temporal) , hinge width (45 vs. 90 degrees), and flap thickness on corneal sensation and dry eye after IntraLase LASIK.

    pre operative and 1 day, 1 week, 1 month, 3 months, 6 months, and 12 months post-operative

Study Arms (3)

Hinge position

ACTIVE COMPARATOR

superior vs. temporal

Procedure: LASIK

Hinge width

ACTIVE COMPARATOR

45 vs 90 degrees

Procedure: LASIK

Flap Thickness

ACTIVE COMPARATOR

110 vs 130 microns

Procedure: LASIK

Interventions

LASIKPROCEDURE
Flap ThicknessHinge positionHinge width

Eligibility Criteria

Age20 Years - 70 Years
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Refractive error: Myopia \< 12 D, with astigmatism \< 3 D,
  • Age \> 20 y/o
  • Regular corneal curvature, sufficient corneal thickness, appropriate pupil size, normal slit lamp examination
  • Informed consent to permit us to use their records for this study without using name, medical record number, or date of surgery.

You may not qualify if:

  • Pregnant/nursing
  • Systemic collagen vascular disease
  • Autoimmune disease
  • Severe dry eyes

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Cornea Clinic, Kellogg Eye Center

Ann Arbor, Michigan, 48105, United States

Location

MeSH Terms

Conditions

Myopia

Interventions

Keratomileusis, Laser In Situ

Condition Hierarchy (Ancestors)

Refractive ErrorsEye Diseases

Intervention Hierarchy (Ancestors)

Corneal Surgery, LaserLaser TherapyTherapeuticsAblation TechniquesSurgical Procedures, OperativeKeratectomyRefractive Surgical ProceduresOphthalmologic Surgical Procedures
0

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
NONE
Purpose
TREATMENT
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
erry J Bergstrom Collegiate Professor of Resident Education in Ophthalmology and Visual Sciences and Associate Professor of Oph, Ophthalmology & Visual Science

Study Record Dates

First Submitted

December 4, 2008

First Posted

December 5, 2008

Study Start

June 1, 2004

Primary Completion

September 1, 2008

Study Completion

December 1, 2015

Last Updated

February 3, 2016

Record last verified: 2016-02

Locations