Refractive SurgeryNCT03597906
Topography Guided LASIK by Different Protocols for Treatment of Astigmatism
A study testing topography guided ablation, manifest refraction and full topography modified refraction in people with Refractive Surgery, run by Cairo University at 1 site in Egypt.
Trial summary
Background and Rationale: LASIK has been among the highest satisfaction rates of surgical procedures, ranging from 82%-98%. Different ablation profiles have been developed over the years. Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Refractive Surgery
- What is being tested?
- topography guided ablation, manifest refraction and full topography modified refraction
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 30 participants
- Where
- 1 siteEgypt
- Study dates
- 15 Aug 2018to 20 Jan 2020
- 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
- Stable refractive error: Myopic astigmatism ≥ -1.5 D
- Valid Topolyzer maps (at least four out of eight right maps with green analyzed area and the registration box is green).
Who cannot join
- Estimated postoperative residual stromal bed thickness of less than 300µm.
- Glaucomatous patients.
- Patients with keratoconus.
- Patients with pervious refractive surgery.
- History of previous ocular trauma or surgery.
- History of recent herpetic ulcer or viral keratitis.
- Basement membrane disease, history of recurrent corneal erosions.
- Sicca syndrome, dry eye.
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Comparison of the Outcome of Topography Modified Refraction Correction to Standard Clinical Refraction Correction in Myopic Astigmatic Topography-guided LASIK
Background and Rationale:
LASIK has been among the highest satisfaction rates of surgical procedures, ranging from 82%-98%. Different ablation profiles have been developed over the years. The purpose of this study is to validate this novel measurement by comparing the visual outcomes when the TMR is used in myopic astigmatic LASIK to using the standard manifest refraction or the Topolyzer measurements alone.
Objectives :
To evaluate the safety, efficacy and predictability of topography-guided myopic LASIK with three different refraction treatment strategies.
Read the detailed description
Candidates for refractive surgery above 18 years with myopic astigmatism and no previous ocular surgery.
Sample size 60 eyes. surgery:
- 60 eyes of myopic topography-guided LASIK procedures with the same refractive platform (FS200 femtosecond to create a flap between90: 110 μm with diameter 8:9 mm and EX500 excimer lasers) will be randomized for treatment as follows:
- Group A: 20 eyes will be treated using Contoura vision with the standard manifest refraction.
- Group B: 20 eyes will be treated with Contoura vision using the topographic astigmatic power and axis and without change in the spherical power (using the same spherical power as the manifest refraction).
- Group C [TMR]: 20 eyes will be treated with Contoura vision using the topographic astigmatic power and axis and modifying the spherical power to obtain the same spherical equivalent as the manifest refraction. This is done by subtracting half of the difference between topographic astigmatic power and the manifest astigmatic power from the spherical power (topography-modified treatment refraction).
- The standard postoperative treatment is combined steroids and antibiotics eye drops 5 times daily for one week ,then three times daily for three days and lubricant eye drops 5 times daily for six months.
Postoperatively, the patients will be examined at 1 week, 1 month and 3 months. All postoperative follow-up visits included measurement of UDVA, CDVA (if indicated) and refraction, besides full ophthalmological examination and performing pentacam and topolyzer after 3 months
- Conditions
- Refractive Surgery
- Being tested
- topography guided ablation, manifest refraction, full topography modified refraction, partial topography modified refraction
- Keywords
- Topography guided ablation, Astigmatism, LASIK
- Medical subject headings
- Astigmatism
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
topography guided ablationProcedure or surgery
using the data obtained from the topolyzer for correction of refractive errors specially astigmatism we use 3 different treatment protocols
manifest refractionProcedure or surgery
using for ablation the exact manifest refraction
full topography modified refractionProcedure or surgery
full topography modified refraction means changing both sphere and cylinder power in the ablation profile
partial topography modified refractionProcedure or surgery
partial topography modified refraction means changing only cylinder power and axis in the ablation profile
| Study group | Role | What they receive |
|---|---|---|
| Group A: Manifest | Experimental | 20 eyes will be treated using Contoura, topography guided ablation vision with the standard manifest refraction. Receives: Procedure: topography guided ablation; Procedure: manifest refraction |
| Group B: partial TMR | Experimental | 20 eyes will be treated with Contoura vision, topography guided ablation using the topographic astigmatic power and axis and without change in the spherical power (using the same spherical power as the manifest refraction). Receives: Procedure: topography guided ablation; Procedure: partial topography modified refraction |
| Group C: Full TMR | Experimental | 20 eyes will be treated with Contoura vision, topography guided ablation using the topographic astigmatic power and axis and modifying the spherical power to obtain the same spherical equivalent as the manifest refraction. This is done by subtracting half of the difference between topographic astigmatic power and the manifest astigmatic power from the spherical power (topography-modified treatment refraction). Receives: Procedure: topography guided ablation; Procedure: full topography modified refraction |
What is being measured
The primary outcome is the main question the study is designed to answer.
post operative residual astigmatism
measuring the post operative residual astigmatism and comparison between the 3 group to reach to the most accurate protocol.
Measured: 3 months
Secondary outcomes (1)
measurement of the postoperative unaided visual acuity
measurement of the postoperative unaided visual acuity and comparison between the 3 group to reach to the most accurate protocol.
Measured: 3 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted24 Jul 2018
- Study start15 Aug 2018
- Primary completion15 Nov 2019
- Study completion20 Jan 2020
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Refractive SurgeryStudies of the same condition, open and under way.
- More trials run by Cairo UniversityThe 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
- Randomised
- Intervention model
- Parallel groups
- Model description
- A prospective, randomized and comparative interventional study
- Masking
- Double blind
- Who is masked
- Participant, Investigator
- Enrolment
- 30 participants (actual)
Sponsor and investigators
- Lead sponsor
- Cairo University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Fayrouz Aboalazayem, Cairo University
- Investigators
- Mohmed Hosny, MD, Study director, Cairo University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03597906
- Sponsor's protocol ID
- N-18-2018
- Status last verified
- Jan 2020
- First submitted
- 21 Jun 2018
- Last updated
- 28 Jan 2020
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 28 Jan 2020. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Comparison of the Outcome of Topography Modified Refraction Correction to Standard Clinical Refraction Correction in Myopic Astigmatic Topography-guided LASIK
- ClinicalTrials.gov ID
- NCT03597906
- Acronym / sponsor ID
- N-18-2018
- Conditions
- Refractive Surgery
- Keywords
- Topography guided ablation, Astigmatism, LASIK
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 30 participants (actual)
- Lead sponsor
- Cairo UniversityUniversity, hospital or other
- Study start
- 15 Aug 2018 (actual)
- Primary completion
- 15 Nov 2019 (actual)
- Study completion
- 20 Jan 2020 (actual)
- First posted
- 24 Jul 2018 (actual)
- 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.
Background and Rationale:
LASIK has been among the highest satisfaction rates of surgical procedures, ranging from 82%-98%. Different ablation profiles have been developed over the years. The purpose of this study is to validate this novel measurement by comparing the visual outcomes when the TMR is used in myopic astigmatic LASIK to using the standard manifest refraction or the Topolyzer measurements alone.
Objectives :
To evaluate the safety, efficacy and predictability of topography-guided myopic LASIK with three different refraction treatment strategies.
Detailed description
Candidates for refractive surgery above 18 years with myopic astigmatism and no previous ocular surgery.
Sample size 60 eyes. surgery:
- 60 eyes of myopic topography-guided LASIK procedures with the same refractive platform (FS200 femtosecond to create a flap between90: 110 μm with diameter 8:9 mm and EX500 excimer lasers) will be randomized for treatment as follows:
- Group A: 20 eyes will be treated using Contoura vision with the standard manifest refraction.
- Group B: 20 eyes will be treated with Contoura vision using the topographic astigmatic power and axis and without change in the spherical power (using the same spherical power as the manifest refraction).
- Group C [TMR]: 20 eyes will be treated with Contoura vision using the topographic astigmatic power and axis and modifying the spherical power to obtain the same spherical equivalent as the manifest refraction. This is done by subtracting half of the difference between topographic astigmatic power and the manifest astigmatic power from the spherical power (topography-modified treatment refraction).
- The standard postoperative treatment is combined steroids and antibiotics eye drops 5 times daily for one week ,then three times daily for three days and lubricant eye drops 5 times daily for six months.
Postoperatively, the patients will be examined at 1 week, 1 month and 3 months. All postoperative follow-up visits included measurement of UDVA, CDVA (if indicated) and refraction, besides full ophthalmological examination and performing pentacam and topolyzer after 3 months
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind (participant, investigator)
- Number of arms
- 3
- Model description
- A prospective, randomized and comparative interventional study
| Arm | Type | Receives |
|---|---|---|
| Group A: Manifest | Experimental | Procedure: topography guided ablation, Procedure: manifest refraction20 eyes will be treated using Contoura, topography guided ablation vision with the standard manifest refraction. |
| Group B: partial TMR | Experimental | Procedure: topography guided ablation, Procedure: partial topography modified refraction20 eyes will be treated with Contoura vision, topography guided ablation using the topographic astigmatic power and axis and without change in the spherical power (using the same spherical power as the manifest refraction). |
| Group C: Full TMR | Experimental | Procedure: topography guided ablation, Procedure: full topography modified refraction20 eyes will be treated with Contoura vision, topography guided ablation using the topographic astigmatic power and axis and modifying the spherical power to obtain the same spherical equivalent as the manifest refraction. This is done by subtracting half of the difference between topographic astigmatic power and the manifest astigmatic power from the spherical power (topography-modified treatment refraction). |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (2 listed)
- Stable refractive error: Myopic astigmatism ≥ -1.5 D
- Valid Topolyzer maps (at least four out of eight right maps with green analyzed area and the registration box is green).
Key exclusion criteria (8 listed)
- Estimated postoperative residual stromal bed thickness of less than 300µm.
- Glaucomatous patients.
- Patients with keratoconus.
- Patients with pervious refractive surgery.
- History of previous ocular trauma or surgery.
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 |
|---|---|---|
| topography guided ablationusing the data obtained from the topolyzer for correction of refractive errors specially astigmatism we use 3 different treatment protocols | Procedure or surgery | Group A: Manifest, Group B: partial TMR, Group C: Full TMR |
| manifest refractionusing for ablation the exact manifest refraction | Procedure or surgery | Group A: Manifest |
| full topography modified refractionfull topography modified refraction means changing both sphere and cylinder power in the ablation profile | Procedure or surgery | Group C: Full TMR |
| partial topography modified refractionpartial topography modified refraction means changing only cylinder power and axis in the ablation profile | Procedure or surgery | Group B: partial TMR |
Primary outcome
post operative residual astigmatism
Time frame: 3 months
measuring the post operative residual astigmatism and comparison between the 3 group to reach to the most accurate protocol.
1 secondary outcome
measurement of the postoperative unaided visual acuity
Time frame: 3 months
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 28 Jan 2020.
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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.
Mohmed Hosny, MD study director
Cairo University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing topography guided ablation, manifest refraction and full topography modified refraction in people with Refractive Surgery, run by Cairo University at 1 site in Egypt.
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 2 inclusion and 8 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 28 Jan 2020. 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 Egypt. 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?
post operative residual astigmatism (time frame: 3 months). 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 28 Jan 2020.