An interventional study of LALAK and IEK in Corneal Opacity and Keratoconus, sponsored by Oregon Health and Science University. Terminated at 1 site in United States. Open to participants aged 18 Years to 100 Years. Per ClinicalTrials.gov, last updated 2019-01-23.
Sponsored by Oregon Health and Science University · Not applicable, Interventional, and Treatment
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.
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.
37 studies on the registry are indexed under Corneal Opacity; 5 are open to participants now.
This study's enrollment of 5 is below the median of 27 across 20 interventional studies indexed under Corneal Opacity.
Browse Corneal Opacity studies →Oregon Health and Science University is the lead sponsor of 696 studies on the registry; 131 are open to participants now.
Of its 52 completed or terminated interventional studies of FDA-regulated products, 39 (75%) have results posted.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
laser-assisted lamellar anterior keratoplasty. Optical Coherence Tomography, femtosecond laser, topical anesthesia, and Retrobulbar Block or General Anesthesia will be used.
Procedure: LALAK · Device: optical coherence tomography (OCT) · Drug: Topical Anesthesia · Device: femtosecond laser
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
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.
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.
OCT will be used to guide the depth of the graft and donor dissections.
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.
Does LALAK Achieve the Same Level of Post-operative BSCVA as IEK.
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.
Time frame: 24 months
| Milestone | Laser-assisted Lamellar Anterior Keratoplasty | Intralase-enabled Keratoplasty |
|---|---|---|
| Started | 3 | 2 |
| Completed | 1 | 1 |
| Not completed | 2 | 1 |
| Withdrew: Adverse event | 0 | 1 |
| Withdrew: Lost to follow-up | 1 | 0 |
| Withdrew: Screen fail | 1 | 0 |
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.
| logMAR unit | Laser-assisted Lamellar Anterior Keratoplasty | Intralase-enabled Keratoplasty |
|---|---|---|
| Does LALAK Achieve the Same Level of Post-operative BSCVA as IEK. | 0.7 (0.7 to 0.7) | 0.05 (-0.5853 to 0.6853) |
Collected over Data was collected up to 24-months from the date of surgery.. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Laser-assisted Lamellar Anterior Keratoplasty | 0/2 (0%) | 0/2 (0%) | 2/2 (100%) |
| Intralase-enabled Keratoplasty | 0/2 (0%) | 0/2 (0%) | 0/2 (0%) |
| Event | Laser-assisted Lamellar Anterior Keratoplasty | Intralase-enabled Keratoplasty |
|---|---|---|
| Revert to keratoconus patternEye disorders | 1/2 | 0/2 |
| Corneal epithelial defect with interface hazeEye disorders | 1/2 | 0/2 |
| Age, Categorical(Participants) | Laser-assisted Lamellar Anterior Keratoplasty | Intralase-enabled Keratoplasty | Total |
|---|---|---|---|
| <=18 years | 0 | 0 | 0 |
| Between 18 and 65 years | 3 | 2 | 5 |
| >=65 years | 0 | 0 | 0 |
| Sex: Female, Male(Participants) | Laser-assisted Lamellar Anterior Keratoplasty | Intralase-enabled Keratoplasty | Total |
|---|---|---|---|
| Female | 2 | 1 | 3 |
| Male | 1 | 1 | 2 |
| Ethnicity (NIH/OMB)(Participants) | Laser-assisted Lamellar Anterior Keratoplasty | Intralase-enabled Keratoplasty | Total |
|---|---|---|---|
| Hispanic or Latino | 1 | 0 | 1 |
| Not Hispanic or Latino | 2 | 2 | 4 |
| Unknown or Not Reported | 0 | 0 | 0 |
| Race (NIH/OMB)(Participants) | Laser-assisted Lamellar Anterior Keratoplasty | Intralase-enabled Keratoplasty | Total |
|---|---|---|---|
| American Indian or Alaska Native | 0 | 0 | 0 |
| Asian | 0 | 0 | 0 |
| Native Hawaiian or Other Pacific Islander | 0 | 0 | 0 |
| Black or African American | 0 | 0 | 0 |
| White | 3 | 2 | 5 |
| More than one race | 0 | 0 | 0 |
| Unknown or Not Reported | 0 | 0 | 0 |
| Region of Enrollment(participants) | Laser-assisted Lamellar Anterior Keratoplasty | Intralase-enabled Keratoplasty | Total |
|---|---|---|---|
| United States | 3 | 2 | 5 |
PDFs hosted by the registry, ClinicalTrials.gov.
The record gives a start of Aug 2013, a primary completion of Aug 2017 and a completion of Aug 2017. It does not say whether these dates are actual or estimated.
Results were first posted in Jan 2019, 1 year 4 months after primary completion.
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This study is terminated, as verified in Jan 2019. You cannot join it, but the record below documents what was studied.
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