OCT-guided LALAK for KCN

Not Applicable

Terminated

• Conditions: Keratoconus; Corneal Opacity
• Interventions: Procedure: IEK; Procedure: LALAK; Drug: Retrobulbar Block or General Anesthesia; Device: optical coherence tomography (OCT); Drug: Topical Anesthesia; Device: femtosecond laser

• Registration Number: NCT01901614
• Lead Sponsor: Oregon Health and Science University

Brief Summary

The purpose of this study is to determine if a new procedure, called laser-assisted lamellar anterior keratoplasty (LALAK), can achieve the same level of vision with a lower risk of potential complications after surgery compared to another corneal transplant procedure. The current procedure is called Intralase-enabled keratoplasty (IEK) and replaces the entire cornea.

The LALAK procedure involves transplanting only the top layers of the cornea instead of the entire cornea. Only one eye will have this experimental procedure performed. If both eyes need to have surgery your doctor will help you decide on the best non-study option for your other eye.

Detailed Description

Corneal transplantation (keratoplasty) is the most common organ transplant, with 42,606 procedures in the U.S. in 2009. Many surgeons are moving away from full thickness corneal transplantation, also called penetrating keratoplasty (PK), because of risks involving rejection, irregular astigmatism and wound dehiscence. They are moving towards partial thickness (lamellar) transplantations of either the anterior or posterior (endothelial) layers, which can reduce these risks.

The femtosecond laser has been used to create excellent tongue-in-groove junctions between the graft and host in full thickness PK.1 This technique, called IEK (Intralase-enabled keratoplasty), has now become a standard surgical procedure. The tongue-in-groove junction achieved at the circumferential edge of the graft and host leads to a continuous smooth anterior surface and strong wound healing.

The new technique is called dovetail LALAK. In this technique, the femtosecond laser is used to create a 31% anterior lamellar graft with dove tailed side cuts. It is also used to create a shallow anterior lamellar dissection and beveled side cuts on the recipient cornea to match with the dovetail graft.

In the new technique, the depth of the graft and donor dissections will be guided by OCT measurements. The proposed trial will test if the new technique can reproducibly achieve good visual outcomes without the risk of rejection. The outcome of the LALAK procedure will be compared to that of IEK.

Basic Information
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Recruitment & Eligibility
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Study & Design
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Trial Locations

Study Timeline

• Study First Submitted: 2013-07-02
• Study First Submitted QC: 2013-07-12
• Study First Posted: 2013-07-17
• Study Start: 2013-08
• Primary Completion: 2017-08-31
• Study Completion: 2017-08-31
• Results First Submitted: 2018-10-19
• Status Verified: 2019-01
• Results First Submitted QC: 2019-01-16
• Last Update Submitted: 2019-01-16
• Results First Posted: 2019-01-23
• Last Update Posted: 2019-01-23

Recruitment & Eligibility

• Status: TERMINATED
• Sex: All
• Target Recruitment: 5

Inclusion Criteria

• Eyes with keratoconus 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).

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Exclusion Criteria

1. Preoperative corneal thickness less than 400 microns.
2. Corneal edema
3. Central guttata
4. Inability to give informed consent.
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

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Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
IEK	IEK	Intralase-enabled keratoplasty. Femtosecond laser and Retrobulbar Block or General Anesthesia will be used.
LALAK	Topical Anesthesia	laser-assisted lamellar anterior keratoplasty. Optical Coherence Tomography, femtosecond laser, topical anesthesia, and Retrobulbar Block or General Anesthesia will be used.
IEK	Retrobulbar Block or General Anesthesia	Intralase-enabled keratoplasty. Femtosecond laser and Retrobulbar Block or General Anesthesia will be used.
LALAK	LALAK	laser-assisted lamellar anterior keratoplasty. Optical Coherence Tomography, femtosecond laser, topical anesthesia, and Retrobulbar Block or General Anesthesia will be used.
LALAK	optical coherence tomography (OCT)	laser-assisted lamellar anterior keratoplasty. Optical Coherence Tomography, femtosecond laser, topical anesthesia, and Retrobulbar Block or General Anesthesia will be used.
LALAK	femtosecond laser	laser-assisted lamellar anterior keratoplasty. Optical Coherence Tomography, femtosecond laser, topical anesthesia, and Retrobulbar Block or General Anesthesia will be used.
IEK	femtosecond laser	Intralase-enabled keratoplasty. Femtosecond laser and Retrobulbar Block or General Anesthesia will be used.

Primary Outcome Measures

Name	Time	Method
Does LALAK Achieve the Same Level of Post-operative BSCVA as IEK.	24 months	The primary goal of the trial is to determine if LALAK can achieve the same level of postoperative Best Spectacle Corrected Visual Acuity (BSCVA) guided by OCT as IEK. The BSCVA will be measured using a clinic Snellen chart and recorded in the typical Snellen fraction (20/xx) in feet. This will be converted to logMAR form for statistical analysis.

Trial Locations

Locations (1)

Casey Eye Institute, Oregon Health & Science University; 🇺🇸 Portland, Oregon, United States