LALAK for Opacities

NCT01901601 | Withdrawn

• 2 other identifiers: OHSU IRB#00009282R01EY018184
• Study Type: interventional
• Target: N/A
• Locations: 0 countries
• Sites: N/A

Brief Summary

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.

Conditions

STROMAL OPACITIES

Keywords

KERATOPLASTY; STROMAL OPACITIES

Outcome Measures

Primary Outcomes (2)

• BSCVA (Snellen chart)

  A primary outcome measures will be BSCVA (Snellen chart)

  24 months

• intraoperative perforation rate

  A primary outcome measure will be intraoperative perforation rate.

  24 months

Secondary Outcomes (5)

• postoperative refractive error

  24 months

• topographic astigmatism

  24 months

• interface clarity

  24 months

• endothelial cell count

  24 months

• complications

  24 months

Study Arms (2)

LALAK

EXPERIMENTAL

laser-assisted lamellar anterior keratoplasty. Optical Coherence Tomography, femtosecond laser, topical anesthesia, and Retrobulbar Block or General Anesthesia will be used.

Procedure: LALAK; Drug: Retrobulbar Block or General Anesthesia; Device: optical coherence tomography (OCT); Drug: Topical Anesthesia; Device: femtosecond laser

IEK

ACTIVE COMPARATOR

Intralase-enabled keratoplasty. Femtosecond laser and Retrobulbar Block or General Anesthesia will be used.

Procedure: IEK; Drug: Retrobulbar Block or General Anesthesia; Device: femtosecond laser

Interventions

LALAK PROCEDURE

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.

LALAK

IEK PROCEDURE

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.

IEK

Retrobulbar Block or General Anesthesia DRUG

IEK; LALAK

optical coherence tomography (OCT) DEVICE

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.

LALAK

Topical Anesthesia DRUG

LALAK

femtosecond laser DEVICE

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.

IEK; LALAK

Eligibility Criteria

• Age: 18 Years - 100 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• 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).

You may not qualify if:

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

Sponsors & Collaborators

• Oregon Health and Science University: lead
• National Institutes of Health (NIH): collaborator
• National Eye Institute (NEI): collaborator

Related Links

• Related Info

MeSH Terms

Interventions

Anesthesia, General; Tomography, Optical Coherence; Anesthesia

Intervention Hierarchy (Ancestors)

Anesthesia and Analgesia; Tomography, Optical; Optical Imaging; Diagnostic Imaging; Diagnostic Techniques and Procedures; Diagnosis; Tomography; Investigative Techniques

Study Officials

• Winston Chamberlain, MD, PhD

  Casey Eye Institute, Oregon Health & Science University

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Winston Chamberlain, MD, PhD, Assistant Professor of Ophthalmology

Study Record Dates

• First Submitted: July 2, 2013
• First Posted: July 17, 2013
• Study Start: July 1, 2013
• Primary Completion: August 31, 2017
• Study Completion: August 31, 2017
• Last Updated: April 6, 2018

Record last verified: 2018-04