Optical Coherence Tomography Guided Transepithelial Phototherapeutic Keratectomy

This study is currently recruiting participants. (see Contacts and Locations)
Verified April 2014 by Oregon Health and Science University
Sponsor:
Collaborator:
Information provided by (Responsible Party):
David Huang, Oregon Health and Science University
ClinicalTrials.gov Identifier:
NCT01243931
First received: November 18, 2010
Last updated: April 7, 2014
Last verified: April 2014
  Purpose

Optical Coherence Tomography (OCT) machines are non-contact instruments that can measure the depth of scars and other causes of cloudiness in the front of the cornea. The purpose of this study is to determine whether OCT-guided settings for the lasers used for removal of corneal scars and other partial-thickness corneal defects result in improved vision in patients receiving these procedures.


Condition Intervention
Corneal Opacity
Drug: OCT-guided laser phototherapeutic keratectomy

Study Type: Interventional
Study Design: Allocation: Non-Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: Optical Coherence Tomography Guided Transepithelial Phototherapeutic Keratectomy

Further study details as provided by Oregon Health and Science University:

Primary Outcome Measures:
  • Improvement in best spectacle-corrected visual acuity (BSCVA) after PTK [ Time Frame: 3-4, 6-8, and 12-14 months after the PTK procedure ] [ Designated as safety issue: No ]
    The primary goal of the trial is to determine the efficacy of the OCT-guided PTK treatment of corneal opacities. During the course of the trial, we will compare the predictive accuracy of the original OCT-guided PTK planning system to the OCT topography-guided system.


Secondary Outcome Measures:
  • Improvement in uncorrected visual acuity (UCVA), refractive error, and higher order aberrations [ Time Frame: 3-4, 6-8, and 12-14 months after the PTK procedure ] [ Designated as safety issue: No ]
    A second goal is to develop a more sophisticated OCT guidance system incorporating OCT topography of anterior and posterior corneal surfaces and to develop a mathematical model that relates epithelial thickness variation to corneal mean curvature. During the course of the trial, we will compare the predictive accuracy of the original OCT-guided PTK planning system to the OCT topography-guided system.


Estimated Enrollment: 20
Study Start Date: June 2011
Estimated Study Completion Date: July 2016
Estimated Primary Completion Date: July 2016 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Surgery
OCT is assisting in surgery guidance.
Drug: OCT-guided laser phototherapeutic keratectomy
Preoperative measurements from the OCT are used to assist the calculation in deciding the laser depth settings for removal of anterior corneal opacities and defects in the phototherapeutic PTK procedure. The surgeon uses the OCT data to plan a range of treatment parameters to remove most of the opacity while preserving at least 250 microns of residual corneal stroma.
Other Names:
  • Manufacturer/Name OCT Technology 510(K)
  • Optovue/RTVue-CAM Fourier-domain K071250
  • Bioptigen/Bioptigen Fourier-domain K063343
  • Zeiss/Visante Time-domain K051789

Detailed Description:

The long-term goal of this project is to utilize newly available very high-speed OCT technology to guide surgical treatments of corneas with superficial opacities and irregularities. OCT is well known for its exquisite resolution, but until recently it has not had sufficient speed to capture the shape of the cornea because of eye motion during OCT scanning. The development of Fourier-domain OCT (FD-OCT) technology has made the requisite speed possible.

Eyes with superficial opacities (corneal scars and stromal dystrophies) can be treated by phototherapeutic keratectomy (PTK). Currently, many surgeons rely on subjective slit-lamp impression of opacity depth to guide PTK and repeat slit-lamp examinations during surgery to determine if the opacity has been sufficiently reduced. Unpredictable hyperopic shifts can occur after PTK. The aim of this project is to develop methods for imaging the cornea with an FD-OCT system that will precisely measure corneal shape and use this information to guide surgery. Patients with irregularly shaped corneas could have their vision restored by reshaping the corneas with a procedure that combines the precision of OCT and lasers.

  Eligibility

Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • Patients with vision primarily limited by superficial opacities and irregularities that could be removed by PTK while leaving at least 250 µm.

Exclusion Criteria:

  • Inability to give informed consent
  • Inability to maintain stable fixation for OCT imaging
  • Inability to commit to required visits to complete the study
  • Deep corneal opacities and irregularities
  • Cataracts, retinal disease, glaucoma, or other eye conditions that may limit the visual outcome after surgery
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01243931

Contacts
Contact: Janice Ladwig 503-494-8024 ladwig@ohsu.edu
Contact: Denny Romfh, OD 503-494-4351 romfhd@ohsu.edu

Locations
United States, Oregon
Casey Eye Institute, Oregon Health & Science University Recruiting
Portland, Oregon, United States, 97239
Contact: Janice Ladwig    503-494-8024    ladwig@ohsu.edu   
Contact: Denny Romfh    503-494-4351    romfhd@ohsu.edu   
Principal Investigator: Frederick (Rick) W. Fraunfelder, MD         
Sponsors and Collaborators
Oregon Health and Science University
Investigators
Principal Investigator: Frederick (Rick) W. Fraunfelder, MD Casey Eye Institute, Oregon Health & Science University
  More Information

No publications provided

Responsible Party: David Huang, Rick Fraunfelder, MD, Director of Cornea and Refractive Surgery, Assistant Professor of Ophthalmology, Oregon Health and Science University
ClinicalTrials.gov Identifier: NCT01243931     History of Changes
Other Study ID Numbers: OHSU IRB #00006612-PTK, R01EY018184
Study First Received: November 18, 2010
Last Updated: April 7, 2014
Health Authority: United States: Institutional Review Board

Keywords provided by Oregon Health and Science University:
Phototherapeutic keratectomy
Optical coherence tomography
Corneal opacity

Additional relevant MeSH terms:
Corneal Opacity
Corneal Diseases
Eye Diseases

ClinicalTrials.gov processed this record on September 22, 2014