KeratoconusNCT00384501
Management of Patients With Keratoconus With Intacs
A study testing Intacs in people with Keratoconus, run by University Hospital of Crete.
Trial summary
Purpose To evaluate long-term follow up of Intacs microthin prescription inserts (Addition Technology Inc, Fremont, Calif) for the management of keratoconus. Design A long-term (five years) retrospective, follow-up study Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Keratoconus
- What is being tested?
- Intacs
- Type of treatment
- Medical device
- How many people
- 25 participants
- Where
- No sites listed yet
- Study dates
- Jan 2000to Jul 2006
- 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 years and older
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- All patients had clear central corneas and contact lens intolerance (rigid gas permeable contact lenses intolerance, frequent contact lens displacement, unsatisfactory visual acuity),
Who cannot join
- history of herpes keratitis; diagnosed autoimmune disease; and systemic connective tissue disease.
About this study
Official title: Intacs for the Treatment of Keratoconus
Purpose To evaluate long-term follow up of Intacs microthin prescription inserts (Addition Technology Inc, Fremont, Calif) for the management of keratoconus.
Design A long-term (five years) retrospective, follow-up study
Read the detailed description
Subjects and Methods
Ethical committee approval was obtained for the original trial, and patients were asked to sign an informed consent form (in accordance with Institutional guidelines and to the Declaration of Helsinki) before treatment and for further follow-up examinations. The registration information for this clinical trial is available to the public through the National Institute of Health database.
The surgical procedure was done under topical anesthesia. Two Intacs segments of 0.45-mm thickness were inserted so as to embrace the steepest keratoconus meridian, according to the topographic image, aiming at maximal flattening.
The corneal thickness was measured intraoperatively at the incision site and peripherally in the cornea along the ring placement markings with ultrasonic pachymetry (Sonogage, Cleveland, Ohio, USA). Using a diamond knife, set at 70% of the thinnest corneal measurement, a 0.9-mm radial incision was formed, and corneal pockets were created using two Sinskey hooks and a Suarez spreader. Two corneal tunnels were then formed using clockwise and counterclockwise dissectors under suction created by a vacuum-centering guide. The two polymethyl methacrylate (PMMA) segments (0.45-mm thickness) were implanted in the respective corneal tunnels, maintaining a space of approximately 2.0-mm between their ends and 1.5 mm between the opposite edge of each segment and the edge of the incision. The incision site was sutured using a single 10/0 nylon stitch.
Postoperative evaluation Postoperatively, all eyes received antibiotic/steroid combination eye drops 4 times per day for 2 weeks. In addition, all patients were instructed to use preservative-free artificial tears frequently. The sutures were removed 2 weeks after surgery.
Group differences for continuous variables were tested using the paired Student t tests. The change in manifest refraction (spherical equivalent) (MRSE) and topographic k values and topographic astigmatism were plotted over time to determine long-term stability, and the difference as a function of time was analyzed using paired 2-tailed t tests (at time intervals of preoperative to 1 month, 1 to 3 months, 3 to 6 months, 6 to 12 months, and every year of follow up period). Results are presented as means + standard deviation [SD]. A P value less than .05 was regarded as statistically significant.
- Conditions
- Keratoconus
- Being tested
- Intacs
- Keywords
- keratoconus, Intacs
- Medical subject headings
- Keratoconus
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
IntacsDevice
What is being measured
The primary outcome is the main question the study is designed to answer.
refractive stability, UCVA, BSCVA, complications
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted6 Oct 2006 (estimated)
- Study startJan 2000
- Study completionJul 2006
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for KeratoconusStudies of the same condition, open and under way.
- 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
- 25 participants
Sponsor and investigators
- Lead sponsor
- University Hospital of Crete
- Sponsor type
- University, hospital or other
- Investigators
- George D Kymionis, M.D., Ph.D, Principal investigator, University of Crete
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT00384501
- Sponsor's protocol ID
- PEPAGNI-6175
- Status last verified
- Oct 2006
- First submitted
- 5 Oct 2006
- Last updated
- 6 Oct 2006
- Results posted
- No
Publications
Alio JL, Shabayek MH, Artola A. Intracorneal ring segments for keratoconus correction: long-term follow-up. J Cataract Refract Surg. 2006 Jun;32(6):978-85. doi: 10.1016/j.jcrs.2006.02.044.
PubMed 16814056
Study at a glance
From the registry record, last updated by the sponsor on 6 Oct 2006. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Intacs for the Treatment of Keratoconus
- ClinicalTrials.gov ID
- NCT00384501
- Acronym / sponsor ID
- PEPAGNI-6175
- Conditions
- Keratoconus
- Keywords
- keratoconus, Intacs
- Study type
- Interventional
- Recruitment status
- Terminated
- Enrolment
- 25 participants
- Lead sponsor
- University Hospital of CreteUniversity, hospital or other
- Study start
- Jan 2000
- Study completion
- Jul 2006
- First posted
- 6 Oct 2006 (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.
Purpose To evaluate long-term follow up of Intacs microthin prescription inserts (Addition Technology Inc, Fremont, Calif) for the management of keratoconus.
Design A long-term (five years) retrospective, follow-up study
Detailed description
Subjects and Methods
Ethical committee approval was obtained for the original trial, and patients were asked to sign an informed consent form (in accordance with Institutional guidelines and to the Declaration of Helsinki) before treatment and for further follow-up examinations. The registration information for this clinical trial is available to the public through the National Institute of Health database.
The surgical procedure was done under topical anesthesia. Two Intacs segments of 0.45-mm thickness were inserted so as to embrace the steepest keratoconus meridian, according to the topographic image, aiming at maximal flattening.
The corneal thickness was measured intraoperatively at the incision site and peripherally in the cornea along the ring placement markings with ultrasonic pachymetry (Sonogage, Cleveland, Ohio, USA). Using a diamond knife, set at 70% of the thinnest corneal measurement, a 0.9-mm radial incision was formed, and corneal pockets were created using two Sinskey hooks and a Suarez spreader. Two corneal tunnels were then formed using clockwise and counterclockwise dissectors under suction created by a vacuum-centering guide. The two polymethyl methacrylate (PMMA) segments (0.45-mm thickness) were implanted in the respective corneal tunnels, maintaining a space of approximately 2.0-mm between their ends and 1.5 mm between the opposite edge of each segment and the edge of the incision. The incision site was sutured using a single 10/0 nylon stitch.
Postoperative evaluation Postoperatively, all eyes received antibiotic/steroid combination eye drops 4 times per day for 2 weeks. In addition, all patients were instructed to use preservative-free artificial tears frequently. The sutures were removed 2 weeks after surgery.
Group differences for continuous variables were tested using the paired Student t tests. The change in manifest refraction (spherical equivalent) (MRSE) and topographic k values and topographic astigmatism were plotted over time to determine long-term stability, and the difference as a function of time was analyzed using paired 2-tailed t tests (at time intervals of preoperative to 1 month, 1 to 3 months, 3 to 6 months, 6 to 12 months, and every year of follow up period). Results are presented as means + standard deviation [SD]. A P value less than .05 was regarded as statistically significant.
Study design
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Single group
- Masking
- None (open label)
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (1 listed)
- All patients had clear central corneas and contact lens intolerance (rigid gas permeable contact lenses intolerance, frequent contact lens displacement, unsatisfactory visual acuity),
Key exclusion criteria (1 listed)
- history of herpes keratitis; diagnosed autoimmune disease; and systemic connective tissue disease.
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 |
|---|---|---|
| Intacs | Device | – |
Primary outcome
refractive stability, UCVA, BSCVA, complications
Results and safety
The study was stopped early. Results are not available in the source record.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 6 Oct 2006.
- Results publication: PubMed 16814056Alio JL, Shabayek MH, Artola A. Intracorneal ring segments for keratoconus correction: long-term follow-up. J Cataract Refract Surg. 2006 Jun;32(6):978-85. doi: 10.1016/j.jcrs.2006.02.044.
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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.
George D Kymionis, M.D., Ph.D principal investigator
University of Crete
Questions about this trial
What is this clinical trial studying?
A study testing Intacs in people with Keratoconus, run by University Hospital of Crete.
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 1 inclusion and 1 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: stopped early, as of the sponsor's last update on 6 Oct 2006. Status can change between updates, so confirm with the study contact before making plans.
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 was stopped early. Results are not available in the source record.
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?
refractive stability, UCVA, BSCVA, complications. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT00384501, which also lists 1 linked publication.
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 6 Oct 2006.