Trial record 8 of 9 for:    Open Studies | corneal laser surgery

LALAK for Opacities

This study is currently recruiting participants. (see Contacts and Locations)
Verified October 2014 by Oregon Health and Science University
Sponsor:
Collaborators:
Information provided by (Responsible Party):
David Huang, Oregon Health and Science University
ClinicalTrials.gov Identifier:
NCT01901601
First received: July 2, 2013
Last updated: October 14, 2014
Last verified: October 2014
  Purpose

The purpose of this protocol is to compare and develop new surgical technique of partial-thickness corneal transplantation for treating corneal opacity. A newly developed technique, "dovetail" laser-assisted lamellar anterior keratoplasty (LALAK), will be tested and compared with standard full-thickness corneal transplantation, Intralase-enabled keratoplasty (IEK). The new LALAK technique replaces only the front portion of the cornea and does not have the risks associated with conventional IEK. Additionally, optical coherence tomography (OCT) will be used to guide the depth of the graft and donor dissections.

The data will be analyzed to understand whether the new technique (LALAK) can repeatedly achieve good visual outcomes with lower risk from the operation compared to the visual outcomes and risk associated with the current standard of care, IEK.


Condition Intervention
STROMAL OPACITIES
Procedure: LALAK
Procedure: IEK
Drug: Retrobulbar Block or General Anesthesia
Device: optical coherence tomography (OCT)
Drug: Topical Anesthesia
Device: femtosecond laser

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: Randomized Clinical Trial of OCT-Guided Laser-Assisted Lamellar Anterior Keratoplasty in Adults for Stromal Opacities

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

Primary Outcome Measures:
  • BSCVA (Snellen chart) [ Time Frame: 24 months ] [ Designated as safety issue: Yes ]
    A primary outcome measures will be BSCVA (Snellen chart)

  • intraoperative perforation rate [ Time Frame: 24 months ] [ Designated as safety issue: Yes ]
    A primary outcome measure will be intraoperative perforation rate.


Secondary Outcome Measures:
  • postoperative refractive error [ Time Frame: 24 months ] [ Designated as safety issue: Yes ]
    A secondary outcome measures will be postoperative refractive error

  • topographic astigmatism [ Time Frame: 24 months ] [ Designated as safety issue: Yes ]
    A secondary outcome measures will be topographic astigmatism

  • interface clarity [ Time Frame: 24 months ] [ Designated as safety issue: Yes ]
    A secondary outcome measures will be interface clarity (masked OCT and confocal microscopy grading)

  • endothelial cell count [ Time Frame: 24 months ] [ Designated as safety issue: Yes ]
    A secondary outcome measures will be endothelial cell count (specular microscopy)

  • complications [ Time Frame: 24 months ] [ Designated as safety issue: Yes ]
    A secondary outcome measures will be complications (rejection, interface opacification, others).


Estimated Enrollment: 40
Study Start Date: July 2013
Estimated Study Completion Date: August 2016
Estimated Primary Completion Date: August 2016 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: LALAK
laser-assisted lamellar anterior keratoplasty. Optical Coherence Tomography, femtosecond laser, topical anesthesia, and Retrobulbar Block or General Anesthesia will be used.
Procedure: LALAK
  1. A "dovetail" shaped cut will be made on the graft using a femtosecond laser at the eye bank. The cut depth will be proportional to the central stromal thickness of the graft. This graft will be separated from stromal bed by eye bank personnel for examination of the cut surface. High-quality graft will be replaced in preservation medium and shipped to the surgeon prior to surgery.
  2. The host cornea will receive femtosecond laser cut consisting of a shallow lamellar cut with angled side cut to match the dovetail graft in a tongue-in-groove fashion. The femtosecond laser treatments will be performed under topical anesthesia in the laser suite. The femtosecond laser is an FDA-approved device for use in this indication (corneal transplantation including lamellar keratoplasty). A protective eye shield is placed over the eye. The graft will be sutured into the host bed.
Drug: Retrobulbar Block or General Anesthesia Device: optical coherence tomography (OCT)
OCT will be used to guide the depth of the graft and donor dissections. The OCT systems to be used in this study will be the RTVue (Optovue, Inc., Fremont, CA) or the Visante (Carl Zeiss Meditec, Inc., Dublin, CA). Both are FDA-approved for the mapping of corneal thickness.
Drug: Topical Anesthesia Device: femtosecond laser
The femtosecond laser system to be used in this study for host cornea preparation will be the Intralase FS system (iFS, AMO, Inc., Santa Ana, CA). The iFS is FDA-approved for corneal surgery including full thickness and lamellar keratoplasty. Eye banks use earlier versions of the Intralase system which are also FDA approved for this indication.
Active Comparator: IEK
Intralase-enabled keratoplasty. Femtosecond laser and Retrobulbar Block or General Anesthesia will be used.
Procedure: IEK
  1. A full thickness graft will be prepared at the eye bank with zigzag side cuts prepared with a femtosecond laser. The graft is separated from the rim, replaced in the preservation medium, and shipped to the surgeon prior to the surgery.
  2. In the laser suite, the host cornea will be cut with the femtosecond laser with zigzag side cuts leaving a 70-100 micron bridge. A protective eye shield is placed over the eye. The graft will be sutured into the host bed.
Drug: Retrobulbar Block or General Anesthesia Device: femtosecond laser
The femtosecond laser system to be used in this study for host cornea preparation will be the Intralase FS system (iFS, AMO, Inc., Santa Ana, CA). The iFS is FDA-approved for corneal surgery including full thickness and lamellar keratoplasty. Eye banks use earlier versions of the Intralase system which are also FDA approved for this indication.

  Eligibility

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

Inclusion Criteria:

  • Eyes with corneal opacities that cannot be adequately or safely corrected with spectacles, contact lens or excimer laser surface ablation. The cornea must have healthy endothelium (endothelial cell density > 1,500/mm2).

Exclusion Criteria:

  1. Preoperative corneal thickness less than 400 microns.
  2. Inability to give informed consent.
  3. Corneal edema
  4. Central guttata
  5. Inability to maintain stable fixation for OCT imaging.
  6. Inability to commit to required visits to complete the study.
  7. Eyes with concurrent cataract, retinal diseases, glaucoma, or other eye conditions that may limit the visual outcome after surgery.
  8. Patients with severe collagen vascular diseases or ocular surface disorders
  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: NCT01901601

Contacts
Contact: Janice Ladwig 503-494-8024 ladwig@ohsu.edu
Contact: Denny Romfh 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   
Principal Investigator: Winston Chamberlain, MD, PhD         
Sub-Investigator: David Huang, MD, PhD         
Sponsors and Collaborators
Oregon Health and Science University
Investigators
Principal Investigator: Winston Chamberlain, MD, PhD Casey Eye Institute, Oregon Health & Science University
  More Information

Additional Information:
No publications provided

Responsible Party: David Huang, Winston Chamberlain, MD, PhD, Assistant Professor of Ophthalmology, Oregon Health and Science University
ClinicalTrials.gov Identifier: NCT01901601     History of Changes
Other Study ID Numbers: OHSU IRB#00009282, R01EY018184
Study First Received: July 2, 2013
Last Updated: October 14, 2014
Health Authority: United States: Institutional Review Board

Keywords provided by Oregon Health and Science University:
KERATOPLASTY
STROMAL OPACITIES

Additional relevant MeSH terms:
Anesthetics
Central Nervous System Depressants
Physiological Effects of Drugs
Pharmacologic Actions
Central Nervous System Agents
Therapeutic Uses

ClinicalTrials.gov processed this record on October 16, 2014