KeratoconusFLAKNCT00802776
Femtosecond Laser Assisted Keratoplasty
A study testing Femtosecond laser assisted keratoplasty and PKP in people with Keratoconus, run by University of Michigan at 1 site in United States.
Trial summary
Penetrating keratoplasty (PKP) is corneal transplantation performed by using round trephine blades to create matched circumferential incisions in both the diseased cornea and the donor cornea. Read more about this study
- Who is it for?
- Ages 18 to 60 years
- Conditions the study is for
- Keratoconus
- What is being tested?
- Femtosecond laser assisted keratoplasty and PKP
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 24 participants
- Where
- 1 siteUnited States
- Study dates
- Oct 2007to Jan 2016
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 60 years
- All sexes
- No healthy volunteers
- Adult
Who may be able to join
- Corneal opacification.
- Reduced ETDRS-measured, best corrected, distance visual acuity to 20/40 or worse.
- Ability to participate in follow-up visits.
- Signed, informed consent.
Who cannot join
- Corneal opacification adequately dense to obscure visualization of iris.
- ETDRS-measured, best-corrected, distance visual acuity of 20/30 or better.
- Corneal thickness greater than 1200 µm at the 9 mm peripheral zone.
- Severe corneal thinning including descemetocoele with impending corneal rupture.
- Prior PKP or incisional surgery that may provide a potential space into which the gas produced by the procedure can escape.
- Poor visual potential in the non-study eye (VA of 20/100 or less, without potential for improvement by the examining ophthalmologist's judgment).
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- History of glaucoma, including steroid response rise in intraocular pressure.
- Active intraocular inflammation or infection.
- Age 18 or younger.
- Unable to return for scheduled follow-up examinations.
- Other medical condition(s) that will likely prevent long term follow-up.
Trial locations and contacts
1 site in 1 country.
United States1 site
Cornea Clinic, Kellogg Eye Center
Ann Arbor, Michigan, 48105
About this study
Official title: Comparison of Femtosecond Laser-Assisted and Traditional Keratoplasty for Keratoconus
Penetrating keratoplasty (PKP) is corneal transplantation performed by using round trephine blades to create matched circumferential incisions in both the diseased cornea and the donor cornea. The donor tissue graft is then secured in place with sutures which are usually removed postoperatively.The primary surgical goals are the preservation of a clear graft and improvement of vision. Surgical outcomes are limited by donor-recipient junction mismatch, astigmatism, rejection, infection and wound dehiscence.
The femtosecond laser is a focusable, infrared laser capable of cutting tissue at various depths and in a range of patterns, and is currently being used to create corneal lamellar flaps in LASIK surgery. The laser parameters can be adjusted for submicron precision in cutting desired diameters, depths and shapes in the cornea, with minimal collateral injury. This technology is now capable of creating full-thickness corneal trephinations with customized locking edges at the graft-host junction between the donor and recipient corneas in Femtosecond Laser-Assisted Keratoplasty (FLAK). This approach may allow for better wound junction of the donor and recipient corneas, which in turn may also significantly reduce astigmatism, improve wound healing and visual recovery.
Read more
This pilot study will help us determine optimal femtosecond laser spot size, separation, fluence, and energy which result in the best graft-host fit.
The specific aim is to investigate postoperative physiology and biomechanics after FLAK in human eyes.
Read the detailed description
Penetrating keratoplasty (PKP) or full-thickness corneal transplantation is a common and highly successful method to restore vision decreased by corneal opacification. Surgery is performed by using round trephine blades to create matched circumferential incisions in both the diseased cornea and the donor cornea. Several types of blades are currently available to create uniform corneal cuts. The donor tissue graft is then secured in place with sutures which are usually removed postoperatively after one to two years. The primary surgical goals are the preservation of a clear graft and improvement of vision. Surgical outcomes are limited by donor-recipient junction mismatch, astigmatism, rejection, infection and wound dehiscence.
The femtosecond laser is a focusable, infrared laser capable of cutting tissue at various depths and in a range of patterns, and is currently being used to create corneal lamellar flaps in LASIK surgery. The laser parameters can be adjusted for submicron precision in cutting desired diameters, depths and shapes in the cornea, with minimal collateral injury. This technology is now capable of creating full-thickness corneal trephinations with customized locking edges at the graft-host junction between the donor and recipient corneas in Femtosecond Laser-Assisted Keratoplasty (FLAK). This approach may allow for better wound junction of the donor and recipient corneas, which in turn may also significantly reduce astigmatism, improve wound healing and visual recovery.
Although the femtosecond laser has been approved by the FDA for use in corneal transplants, it has not been compared to standard corneal transplant techniques. This pilot study will help us determine optimal femtosecond laser spot size, separation, fluency, and energy which result in the best graft-host fit. Surgical eligibility criteria, including preoperative diagnoses, as well as possible associated medical and ophthalmic conditions for the eventual multi-center study will be defined. Primary outcome measures, which include corneal refractive power measurements, serial endothelial-cell counts to assess endothelial survival and vision-specific quality of life surveys, will be evaluated. The specific aim is to investigate postoperative physiology and biomechanics after FLAK in human eyes. The significance is that FLAK presents corneal surgeons with an opportunity to avoid some problems of PKP and offers a safer and more precise approach to treating visually disabling diseases secondary to corneal opacification.
- Conditions
- Keratoconus
- Being tested
- Femtosecond laser assisted keratoplasty, PKP
- Medical subject headings
- Keratoconus
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Femtosecond laser assisted keratoplastyProcedure or surgery
PKPProcedure or surgery
| Study group | Role | What they receive |
|---|---|---|
| FLAK | Active comparator | Femtosecond laser assisted keratoplasty Receives: Procedure: Femtosecond laser assisted keratoplasty |
| PKP | Active comparator | Penetrating Keratoplasty Receives: Procedure: PKP |
What is being measured
The primary outcome is the main question the study is designed to answer.
Investigate postoperative physiology and biomechanics after Femtosecond Laser Assisted Keratoplasty in human eyes.
Measured: Preoperatively and 1day, 1week and 1, 3, 6, 12, 18 and 24 months post operatively
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted5 Dec 2008 (estimated)
- Study startOct 2007
- Primary completionDec 2010
- Study completionJan 2016
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for KeratoconusStudies of the same condition, open and under way.
- More trials run by University of MichiganThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 24 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of Michigan
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Shahzad Mian, University of Michigan
- Investigators
- Shahzad Mian, MD, Principal investigator, University of Michigan Kellogg Eye Center
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT00802776
- Sponsor's protocol ID
- HUM 15615-FLAK
- Acronym
- FLAK
- Status last verified
- Mar 2017
- First submitted
- 4 Dec 2008
- Last updated
- 15 Mar 2017
- Results posted
- No
- Data monitoring committee
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 15 Mar 2017. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Comparison of Femtosecond Laser-Assisted and Traditional Keratoplasty for Keratoconus
- ClinicalTrials.gov ID
- NCT00802776
- Acronym / sponsor ID
- FLAK / HUM 15615-FLAK
- Conditions
- Keratoconus
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 24 participants (actual)
- Lead sponsor
- University of MichiganUniversity, hospital or other
- Study start
- Oct 2007
- Primary completion
- Dec 2010 (actual)
- Study completion
- Jan 2016 (actual)
- First posted
- 5 Dec 2008 (estimated)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Penetrating keratoplasty (PKP) is corneal transplantation performed by using round trephine blades to create matched circumferential incisions in both the diseased cornea and the donor cornea. The donor tissue graft is then secured in place with sutures which are usually removed postoperatively.The primary surgical goals are the preservation of a clear graft and improvement of vision. Surgical outcomes are limited by donor-recipient junction mismatch, astigmatism, rejection, infection and wound dehiscence.
The femtosecond laser is a focusable, infrared laser capable of cutting tissue at various depths and in a range of patterns, and is currently being used to create corneal lamellar flaps in LASIK surgery. The laser parameters can be adjusted for submicron precision in cutting desired diameters, depths and shapes in the cornea, with minimal collateral injury. This technology is now capable of creating full-thickness corneal trephinations with customized locking edges at the graft-host junction between the donor and recipient corneas in Femtosecond Laser-Assisted Keratoplasty (FLAK). This approach may allow for better wound junction of the donor and recipient corneas, which in turn may also significantly reduce astigmatism, improve wound healing and visual recovery.
This pilot study will help us determine optimal femtosecond laser spot size, separation, fluence, and energy which result in the best graft-host fit.
The specific aim is to investigate postoperative physiology and biomechanics after FLAK in human eyes.
Detailed description
Penetrating keratoplasty (PKP) or full-thickness corneal transplantation is a common and highly successful method to restore vision decreased by corneal opacification. Surgery is performed by using round trephine blades to create matched circumferential incisions in both the diseased cornea and the donor cornea. Several types of blades are currently available to create uniform corneal cuts. The donor tissue graft is then secured in place with sutures which are usually removed postoperatively after one to two years. The primary surgical goals are the preservation of a clear graft and improvement of vision. Surgical outcomes are limited by donor-recipient junction mismatch, astigmatism, rejection, infection and wound dehiscence.
The femtosecond laser is a focusable, infrared laser capable of cutting tissue at various depths and in a range of patterns, and is currently being used to create corneal lamellar flaps in LASIK surgery. The laser parameters can be adjusted for submicron precision in cutting desired diameters, depths and shapes in the cornea, with minimal collateral injury. This technology is now capable of creating full-thickness corneal trephinations with customized locking edges at the graft-host junction between the donor and recipient corneas in Femtosecond Laser-Assisted Keratoplasty (FLAK). This approach may allow for better wound junction of the donor and recipient corneas, which in turn may also significantly reduce astigmatism, improve wound healing and visual recovery.
Although the femtosecond laser has been approved by the FDA for use in corneal transplants, it has not been compared to standard corneal transplant techniques. This pilot study will help us determine optimal femtosecond laser spot size, separation, fluency, and energy which result in the best graft-host fit. Surgical eligibility criteria, including preoperative diagnoses, as well as possible associated medical and ophthalmic conditions for the eventual multi-center study will be defined. Primary outcome measures, which include corneal refractive power measurements, serial endothelial-cell counts to assess endothelial survival and vision-specific quality of life surveys, will be evaluated. The specific aim is to investigate postoperative physiology and biomechanics after FLAK in human eyes. The significance is that FLAK presents corneal surgeons with an opportunity to avoid some problems of PKP and offers a safer and more precise approach to treating visually disabling diseases secondary to corneal opacification.
Study design
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| FLAK | Active comparator | Procedure: Femtosecond laser assisted keratoplastyFemtosecond laser assisted keratoplasty |
| PKP | Active comparator | Procedure: PKPPenetrating Keratoplasty |
Who may qualify
- Ages
- 18 to 60 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (4 listed)
- Corneal opacification.
- Reduced ETDRS-measured, best corrected, distance visual acuity to 20/40 or worse.
- Ability to participate in follow-up visits.
- Signed, informed consent.
Key exclusion criteria (11 listed)
- Corneal opacification adequately dense to obscure visualization of iris.
- ETDRS-measured, best-corrected, distance visual acuity of 20/30 or better.
- Corneal thickness greater than 1200 µm at the 9 mm peripheral zone.
- Severe corneal thinning including descemetocoele with impending corneal rupture.
- Prior PKP or incisional surgery that may provide a potential space into which the gas produced by the procedure can escape.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Femtosecond laser assisted keratoplasty | Procedure or surgery | FLAK |
| PKP | Procedure or surgery | PKP |
Primary outcome
Investigate postoperative physiology and biomechanics after Femtosecond Laser Assisted Keratoplasty in human eyes.
Time frame: Preoperatively and 1day, 1week and 1, 3, 6, 12, 18 and 24 months post operatively
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 15 Mar 2017.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Shahzad Mian, MD principal investigator
University of Michigan Kellogg Eye Center
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Femtosecond laser assisted keratoplasty and PKP in people with Keratoconus, run by University of Michigan at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 11 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 15 Mar 2017. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Investigate postoperative physiology and biomechanics after Femtosecond Laser Assisted Keratoplasty in human eyes. (time frame: Preoperatively and 1day, 1week and 1, 3, 6, 12, 18 and 24 months post operatively). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 15 Mar 2017.