KeratoconusNCT00347230
Intacs for Keratoconus
A study testing Intacs intracorneal ring insertion for the treatment of keratoconus in people with Keratoconus, run by Singapore National Eye Centre at 1 site in Singapore.
Trial summary
To study the effects Intacs intracorneal ring segments(Addition Technology, Inc) insertion in the treatment of keratoconus Read more about this study
- Who is it for?
- Ages 21 years and olderHealthy volunteers can take part
- Conditions the study is for
- Keratoconus
- What is being tested?
- Intacs intracorneal ring insertion for the treatment of keratoconus
- Type of treatment
- Medical device
- How many people
- 20 participants
- Where
- 1 siteSingapore
- Study dates
- Oct 2005to not given
- 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 21 years and older
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Patients must have keratoconus (mild to moderate).
- Visual acuity with contact lenses must be better than or equal to (20/40).
- Patients must be intolerant of contact lenses, i.e., they must be unable to wear contact lenses for a whole day.
- Patients will have a corneal thickness of 425 microns at the site of ICRS (INTACS inserts) placement (the thinnest region of the cornea).
- In terms of general health, patients must not have any illnesses posing an immediate threat to life.
- Patients must have provided written informed consent at least one week prior to surgery.
- Patients must over 21 years of age.
- Patients' contact lenses must have been removed at least one week prior to surgery for soft lenses and two weeks prior to surgery for hard lenses.
Who cannot join
- Positive pregnancy test.
- Breast-feeding.
- History of previous ophthalmologic surgery on the operative eye.
- Patients with corneal stromal disorders.
- Patients with history of herpetic keratitis.
- Patients with retinal disorders.
Show all 13Show fewer
- Corneal grafts.
- Patients refusing to remove contact lenses one week before surgery for soft lenses and two weeks before surgery for hard lenses.
- Patients with amblyopia (VA <1110 for the contralateral eye).
- Patients with corneal thickness <425 microns.
- Patients with TOP <10 mmHg or >21 mmHg.
- Patients taking part in other biomedical research in the 30 days prior to the start of this study.
- Patients with an uncooperative disposition.
Trial locations and contacts
1 site in 1 country.
Singapore1 site, 1 recruiting
- Recruiting
Singapore National Eye Centre
Singapore, 168751
Li - Lim, FRCS(Ed)
About this study
To study the effects Intacs intracorneal ring segments(Addition Technology, Inc) insertion in the treatment of keratoconus
Read the detailed description
The purpose of this evaluation is to study the effects of implanting INTACS inserts, identical to those commercially available to correct myopia, into the corneal stroma of patients with keratoconus (mild to moderate) and having a clear cornea. The principle of the procedure is to flatten the cornea deformed by keratoconus. One or two segments of the same or a different thickness will be selected to reduce the asymmetric astigmatism responsible for the patient impaired visual acuity.
The surgical technique is based on locating the INTACS inserts on the flattest axis of the refractive error, making the incision on the steepest axis, using 150 degree arc length inserts with different sizes (0.250, 0.300, 0.350, 0.400 \& 0.450 mm) according to a nomogram designed for this technique using the INTACS Instrumentation (10-Step Prolate System instruments).
The corneal lamellar channel creation may be performed using the INTACS instrumentation or using the Femtosecond laser (Femtec 20/10 laser[Femtec,Heidelberg Germany])
Primary Assessment Criteria
- Evaluation of the safety of the device for the treatment of patients with keratoconus (mild to moderate)
- Maintenance of best corrected visual acuity (BCVA)
- Improvement in uncorrected visual acuity (UCVA)
- Reduction in manifest refraction spherical equivalent
- Reduction in asymmetric astigmatism
Secondary Assessment Criteria
- Evaluation of the effect of INTACS inserts placement for treatment of corneal ectasia
- Determination of patient satisfaction following the INTACS inserts procedure Patients meeting the eligibility criteria are required to sign a Patient Informed Consent Form prior to study participation.
A thorough examination is perform to evaluate the following:
- Manifest refraction results - Uncorrected visual acuity (UCVA) and best corrected visual acuity (BCVA)
- Cycloplegic refraction results - Uncorrected visual acuity (UCVA) and best corrected visual acuity (BCVA)
- Corneal topography
- Pachymetry
- Step axis location
- Location of incision placement
- Subjective feedback about quality of vision (Excellent, Good, Fair and Poor)
Post-operative Assessment(at 1 day, 1 week, 1 month and 3 months postop)
- Uncorrected visual acuity (UCVA) and best corrected visual acuity with manifest refraction(BCVA) at designated time interval
- Cycloplegic refraction results - Uncorrected visual acuity (UCVA) and best corrected visual acuity (BCVA) at designated time interval
- Corneal topography at designated time interval
- Pachymetry at designated time interval
- Subjective visual outcome ratings over time (Excellent, Good, Fair and Poor)
- Report adverse events
- Conditions
- Keratoconus
- Being tested
- Intacs intracorneal ring insertion for the treatment of keratoconus
- Keywords
- Intacs ring segments, Keratoconus
- Medical subject headings
- Keratoconus
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Intacs intracorneal ring insertion for the treatment of keratoconusDevice
What is being measured
The primary outcome is the main question the study is designed to answer.
Visual acuity
Refraction
Corneal topography
Secondary outcomes (1)
Patient satisfaction following procedure
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted4 Jul 2006 (estimated)
- Study startOct 2005
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (5)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
- 20 participants
Sponsor and investigators
- Lead sponsor
- Singapore National Eye Centre
- Sponsor type
- Other government
- Investigators
- Donald TH Tan, FRCS, Principal investigator, Singapore National Eye Centre
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT00347230
- Sponsor's protocol ID
- R419/14/2005
- Status last verified
- Sep 2005
- First submitted
- 30 Jun 2006
- Last updated
- 7 Jul 2006
- Results posted
- No
Publications
Colin J, Cochener B, Savary G, Malet F, Holmes-Higgin D. INTACS inserts for treating keratoconus: one-year results. Ophthalmology. 2001 Aug;108(8):1409-14. doi: 10.1016/s0161-6420(01)00646-7.
PubMed 11470691Colin J, Cochener B, Savary G, Malet F. Correcting keratoconus with intracorneal rings. J Cataract Refract Surg. 2000 Aug;26(8):1117-22. doi: 10.1016/s0886-3350(00)00451-x.
PubMed 11008037Siganos D, Ferrara P, Chatzinikolas K, Bessis N, Papastergiou G. Ferrara intrastromal corneal rings for the correction of keratoconus. J Cataract Refract Surg. 2002 Nov;28(11):1947-51. doi: 10.1016/s0886-3350(02)01495-5.
PubMed 12457667Schanzlin DJ, Asbell PA, Burris TE, Durrie DS. The intrastromal corneal ring segments. Phase II results for the correction of myopia. Ophthalmology. 1997 Jul;104(7):1067-78. doi: 10.1016/s0161-6420(97)30183-3.
PubMed 9224455Siganos CS, Kymionis GD, Kartakis N, Theodorakis MA, Astyrakakis N, Pallikaris IG. Management of keratoconus with Intacs. Am J Ophthalmol. 2003 Jan;135(1):64-70. doi: 10.1016/s0002-9394(02)01824-x.
PubMed 12504699
Study at a glance
From the registry record, last updated by the sponsor on 7 Jul 2006. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Intacs for Keratoconus
- ClinicalTrials.gov ID
- NCT00347230
- Acronym / sponsor ID
- R419/14/2005
- Conditions
- Keratoconus
- Keywords
- Intacs ring segments, Keratoconus
- Study type
- Interventional
- Recruitment status
- Unknown status
- Enrolment
- 20 participants
- Lead sponsor
- Singapore National Eye CentreOther government
- Study start
- Oct 2005
- First posted
- 4 Jul 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.
To study the effects Intacs intracorneal ring segments(Addition Technology, Inc) insertion in the treatment of keratoconus
Detailed description
The purpose of this evaluation is to study the effects of implanting INTACS inserts, identical to those commercially available to correct myopia, into the corneal stroma of patients with keratoconus (mild to moderate) and having a clear cornea. The principle of the procedure is to flatten the cornea deformed by keratoconus. One or two segments of the same or a different thickness will be selected to reduce the asymmetric astigmatism responsible for the patient impaired visual acuity.
The surgical technique is based on locating the INTACS inserts on the flattest axis of the refractive error, making the incision on the steepest axis, using 150 degree arc length inserts with different sizes (0.250, 0.300, 0.350, 0.400 \& 0.450 mm) according to a nomogram designed for this technique using the INTACS Instrumentation (10-Step Prolate System instruments).
The corneal lamellar channel creation may be performed using the INTACS instrumentation or using the Femtosecond laser (Femtec 20/10 laser[Femtec,Heidelberg Germany])
Primary Assessment Criteria
- Evaluation of the safety of the device for the treatment of patients with keratoconus (mild to moderate)
- Maintenance of best corrected visual acuity (BCVA)
- Improvement in uncorrected visual acuity (UCVA)
- Reduction in manifest refraction spherical equivalent
- Reduction in asymmetric astigmatism
Secondary Assessment Criteria
- Evaluation of the effect of INTACS inserts placement for treatment of corneal ectasia
- Determination of patient satisfaction following the INTACS inserts procedure Patients meeting the eligibility criteria are required to sign a Patient Informed Consent Form prior to study participation.
A thorough examination is perform to evaluate the following:
- Manifest refraction results - Uncorrected visual acuity (UCVA) and best corrected visual acuity (BCVA)
- Cycloplegic refraction results - Uncorrected visual acuity (UCVA) and best corrected visual acuity (BCVA)
- Corneal topography
- Pachymetry
- Step axis location
- Location of incision placement
- Subjective feedback about quality of vision (Excellent, Good, Fair and Poor)
Post-operative Assessment(at 1 day, 1 week, 1 month and 3 months postop)
- Uncorrected visual acuity (UCVA) and best corrected visual acuity with manifest refraction(BCVA) at designated time interval
- Cycloplegic refraction results - Uncorrected visual acuity (UCVA) and best corrected visual acuity (BCVA) at designated time interval
- Corneal topography at designated time interval
- Pachymetry at designated time interval
- Subjective visual outcome ratings over time (Excellent, Good, Fair and Poor)
- Report adverse events
Study design
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Single group
- Masking
- None (open label)
Who may qualify
- Ages
- 21 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (8 listed)
- Patients must have keratoconus (mild to moderate).
- Visual acuity with contact lenses must be better than or equal to (20/40).
- Patients must be intolerant of contact lenses, i.e., they must be unable to wear contact lenses for a whole day.
- Patients will have a corneal thickness of 425 microns at the site of ICRS (INTACS inserts) placement (the thinnest region of the cornea).
- In terms of general health, patients must not have any illnesses posing an immediate threat to life.
Key exclusion criteria (13 listed)
- Positive pregnancy test.
- Breast-feeding.
- History of previous ophthalmologic surgery on the operative eye.
- Patients with corneal stromal disorders.
- Patients with history of herpetic keratitis.
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 intracorneal ring insertion for the treatment of keratoconus | Device | – |
Primary outcome
Visual acuity
Refraction
Corneal topography
1 secondary outcome
Patient satisfaction following procedure
Results and safety
Results are not available in the source record.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 7 Jul 2006.
- Background: PubMed 11470691Colin J, Cochener B, Savary G, Malet F, Holmes-Higgin D. INTACS inserts for treating keratoconus: one-year results. Ophthalmology. 2001 Aug;108(8):1409-14. doi: 10.1016/s0161-6420(01)00646-7.
- Background: PubMed 11008037Colin J, Cochener B, Savary G, Malet F. Correcting keratoconus with intracorneal rings. J Cataract Refract Surg. 2000 Aug;26(8):1117-22. doi: 10.1016/s0886-3350(00)00451-x.
- Background: PubMed 12457667Siganos D, Ferrara P, Chatzinikolas K, Bessis N, Papastergiou G. Ferrara intrastromal corneal rings for the correction of keratoconus. J Cataract Refract Surg. 2002 Nov;28(11):1947-51. doi: 10.1016/s0886-3350(02)01495-5.
- Background: PubMed 9224455Schanzlin DJ, Asbell PA, Burris TE, Durrie DS. The intrastromal corneal ring segments. Phase II results for the correction of myopia. Ophthalmology. 1997 Jul;104(7):1067-78. doi: 10.1016/s0161-6420(97)30183-3.
- Background: PubMed 12504699Siganos CS, Kymionis GD, Kartakis N, Theodorakis MA, Astyrakakis N, Pallikaris IG. Management of keratoconus with Intacs. Am J Ophthalmol. 2003 Jan;135(1):64-70. doi: 10.1016/s0002-9394(02)01824-x.
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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.
Donald TH Tan, FRCS principal investigator
Singapore National Eye Centre
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Intacs intracorneal ring insertion for the treatment of keratoconus in people with Keratoconus, run by Singapore National Eye Centre at 1 site in Singapore.
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 8 inclusion and 13 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: status not confirmed, as of the sponsor's last update on 7 Jul 2006. 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 Singapore. 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?
Results are not available in the source record.
How can a doctor refer a patient or contact the research team?
Contact Li - Lim, FRCS(Ed) (65-63228896, Lim.Li@snec.com.sg), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Visual acuity. The study lists 3 primary outcomes in all. 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 NCT00347230, which also lists 5 linked publications.
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 7 Jul 2006.