Patients With Myopic Spherical Equivalent up to -12 DioptersNCT04738903
Q Value Customized Versus Wavefront Optimized Ablation in Femtosecond Laser-Assisted LASIK
A study testing Femtosecond laser assisted LASIK eye surgery in people with Patients With Myopic Spherical Equivalent up to -12 Diopters, run by Assiut University at 1 site in Egypt.
Trial summary
Corneal asphericity is expressed numerically as the "Q-value". A minus value means that corneal curvature flattens towards the periphery and the cornea is prolate in shape, but when the curvature steepens towards the periphery, the cornea is oblate in shape and has a positive Q-value. Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Patients With Myopic Spherical Equivalent up to -12 Diopters
- What is being tested?
- Femtosecond laser assisted LASIK eye surgery
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 40 participants
- Where
- 1 siteEgypt
- Study dates
- 1 Jun 2020to 30 Jun 2021
- 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
None listed.
Who cannot join
- Patients not candidates for LVC.
- Hyperopic patients or mixed astigmatism.
- Systemic disease that contraindicates LVC.
- Intra- or post-operative complications. 5- Previous corneal surgery
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Q Value Customized Versus Wavefront Optimized Ablation in Femtosecond Laser-Assisted LASIK for Myopia and Myopic Astigmatism. A Contralateral Comparative Study
Corneal asphericity is expressed numerically as the "Q-value". A minus value means that corneal curvature flattens towards the periphery and the cornea is prolate in shape, but when the curvature steepens towards the periphery, the cornea is oblate in shape and has a positive Q-value.
The current study evaluates the effect of LASIK eye surgery on corneal asphericity by comparing 2 software treatment platforms; the Q value customized ablation versus the conventional Wave-front optimized ablation in a fellow eye study pattern.
Read the detailed description
The standard excimer laser correction of myopia is associated with decreased visual quality in the form of a decrease in contrast sensitivity and night vision. This degradation of the visual quality is attributed to changes in the corneal asphericity that increase the high order aberrations (HOAs), such as spherical aberrations because it leads to shifting of the corneal asphericity towards the oblate shape.
The wavefront-optimized (WFO) profile avoids the creation of new HOAs, but it is not able to treat those which are already present pre-operatively.
The Q-adjusted treatments correct the sphero-cylindrical refractive errors and try to maintain the corneal asphericity at the same time, but like the WFO ablation profiles, it is limited to correcting the spherical aberrations and not the non-rotational symmetric HOAs.
Some studies compared Lasers of two different platforms on contralateral eyes of the same patient in order to minimize inter-patient differences such as corneal wound healing and corneal biomechanics. By exclusion of these inter-patient differences, a more accurate judgment on the outcomes can be achieved.
- Being tested
- Femtosecond laser assisted LASIK eye surgery
- Keywords
- Femtosecond LASIK, Q value, Wave-front Optimized (WFO)
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Femtosecond laser assisted LASIK eye surgeryProcedure or surgery
FS-LASIK eye surgery includes corneal flap creation with femtosecond laser using the Femtosecond laser WaveLight FS200 followed by excimer laser vision correction of the patient's refractive error using excimer laser WaveLight EX500.
| Study group | Role | What they receive |
|---|---|---|
| Custom Q treatment group | Active comparator | For every patient, the eye with the greater myopic spherical equivalent (SE) will be assigned for the Custom-Q treatment group. Receives: Procedure: Femtosecond laser assisted LASIK eye surgery |
| Wave-front optimized (WFO) group | Active comparator | For every patient, the other eye with the lesser myopic SE will be assigned for the WFO treatment group Receives: Procedure: Femtosecond laser assisted LASIK eye surgery |
What is being measured
The primary outcome is the main question the study is designed to answer.
Postoperative Q value
Pentacam evaluation of post-LASIK Q value
Measured: 6 months
Secondary outcomes (1)
Postoperative corneal thickness at the pupillary center
Pentacam evaluation of post-LASIK pachymetry at the pupil center
Measured: 6 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted4 Feb 2021
- Study start1 Jun 2020
- Primary completion30 Jun 2021
- Study completion30 Jun 2021
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (2)Papers the sponsor has linked to this study.
- Other trials for Patients With Myopic Spherical Equivalent up to -12 DioptersStudies of the same condition, open and under way.
- More trials run by Assiut 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
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- Single blind
- Who is masked
- Outcomes assessor
- Enrolment
- 40 participants (actual)
Sponsor and investigators
- Lead sponsor
- Assiut University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Mahmoud Abdel-Radi, Assiut University
- Investigators
- Mahmoud Abdel-Radi, MD, Principal investigator, Assiut University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04738903
- Sponsor's protocol ID
- CQLASIK
- Status last verified
- Jul 2021
- First submitted
- 1 Feb 2021
- Last updated
- 20 Jul 2021
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Piao J, Li YJ, Whang WJ, Choi M, Kang MJ, Lee JH, Yoon G, Joo CK. Comparative evaluation of visual outcomes and corneal asphericity after laser-assisted in situ keratomileusis with the six-dimension Amaris excimer laser system. PLoS One. 2017 Feb 10;12(2):e0171851. doi: 10.1371/journal.pone.0171851. eCollection 2017.
PubMed 28187180Mostafa MM, Abdelmotaal H, Abdelazeem K, Goda I, Abdel-Radi M. Q-value customized versus wavefront-optimized ablation in femtosecond laser-assisted LASIK for myopia and myopic astigmatism: a prospective contralateral comparative study. Eye Vis (Lond). 2022 Nov 2;9(1):43. doi: 10.1186/s40662-022-00312-3.
PubMed 36320050
Study at a glance
From the registry record, last updated by the sponsor on 20 Jul 2021. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Q Value Customized Versus Wavefront Optimized Ablation in Femtosecond Laser-Assisted LASIK for Myopia and Myopic Astigmatism. A Contralateral Comparative Study
- ClinicalTrials.gov ID
- NCT04738903
- Acronym / sponsor ID
- CQLASIK
- Keywords
- Femtosecond LASIK, Q value, Wave-front Optimized (WFO)
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 40 participants (actual)
- Lead sponsor
- Assiut UniversityUniversity, hospital or other
- Study start
- 1 Jun 2020 (actual)
- Primary completion
- 30 Jun 2021 (actual)
- Study completion
- 30 Jun 2021 (actual)
- First posted
- 4 Feb 2021 (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.
Corneal asphericity is expressed numerically as the "Q-value". A minus value means that corneal curvature flattens towards the periphery and the cornea is prolate in shape, but when the curvature steepens towards the periphery, the cornea is oblate in shape and has a positive Q-value.
The current study evaluates the effect of LASIK eye surgery on corneal asphericity by comparing 2 software treatment platforms; the Q value customized ablation versus the conventional Wave-front optimized ablation in a fellow eye study pattern.
Detailed description
The standard excimer laser correction of myopia is associated with decreased visual quality in the form of a decrease in contrast sensitivity and night vision. This degradation of the visual quality is attributed to changes in the corneal asphericity that increase the high order aberrations (HOAs), such as spherical aberrations because it leads to shifting of the corneal asphericity towards the oblate shape.
The wavefront-optimized (WFO) profile avoids the creation of new HOAs, but it is not able to treat those which are already present pre-operatively.
The Q-adjusted treatments correct the sphero-cylindrical refractive errors and try to maintain the corneal asphericity at the same time, but like the WFO ablation profiles, it is limited to correcting the spherical aberrations and not the non-rotational symmetric HOAs.
Some studies compared Lasers of two different platforms on contralateral eyes of the same patient in order to minimize inter-patient differences such as corneal wound healing and corneal biomechanics. By exclusion of these inter-patient differences, a more accurate judgment on the outcomes can be achieved.
Study design
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Custom Q treatment group | Active comparator | Procedure: Femtosecond laser assisted LASIK eye surgeryFor every patient, the eye with the greater myopic spherical equivalent (SE) will be assigned for the Custom-Q treatment group. |
| Wave-front optimized (WFO) group | Active comparator | Procedure: Femtosecond laser assisted LASIK eye surgeryFor every patient, the other eye with the lesser myopic SE will be assigned for the WFO treatment group |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (0 listed)
Key exclusion criteria (4 listed)
- Patients not candidates for LVC.
- Hyperopic patients or mixed astigmatism.
- Systemic disease that contraindicates LVC.
- Intra- or post-operative complications. 5- Previous corneal 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 |
|---|---|---|
| Femtosecond laser assisted LASIK eye surgeryFS-LASIK eye surgery includes corneal flap creation with femtosecond laser using the Femtosecond laser WaveLight FS200 followed by excimer laser vision correction of the patient's refractive error using excimer laser WaveLight EX500. | Procedure or surgery | Custom Q treatment group, Wave-front optimized (WFO) group |
Primary outcome
Postoperative Q value
Time frame: 6 months
Pentacam evaluation of post-LASIK Q value
1 secondary outcome
Postoperative corneal thickness at the pupillary center
Time frame: 6 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 20 Jul 2021.
- Background: PubMed 28187180Piao J, Li YJ, Whang WJ, Choi M, Kang MJ, Lee JH, Yoon G, Joo CK. Comparative evaluation of visual outcomes and corneal asphericity after laser-assisted in situ keratomileusis with the six-dimension Amaris excimer laser system. PLoS One. 2017 Feb 10;12(2):e0171851. doi: 10.1371/journal.pone.0171851. eCollection 2017.
- Derived from this study: PubMed 36320050Mostafa MM, Abdelmotaal H, Abdelazeem K, Goda I, Abdel-Radi M. Q-value customized versus wavefront-optimized ablation in femtosecond laser-assisted LASIK for myopia and myopic astigmatism: a prospective contralateral comparative study. Eye Vis (Lond). 2022 Nov 2;9(1):43. doi: 10.1186/s40662-022-00312-3.
- Individual participant dataSharing planned: No
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.
Mahmoud Abdel-Radi, MD principal investigator
Assiut 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 Femtosecond laser assisted LASIK eye surgery in people with Patients With Myopic Spherical Equivalent up to -12 Diopters, run by Assiut 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 0 inclusion and 4 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 20 Jul 2021. 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?
Postoperative Q value (time frame: 6 months). 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 NCT04738903, which also lists 2 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 20 Jul 2021; AzTrials last refreshed its copy on 2 Nov 2026.