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AzTrials

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.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
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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
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.

Egypt1 site
  • TIBA eye center

    Asyut, 71516

Other trials in Egypt

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 groups in NCT04738903
Study groupRoleWhat they receive
Custom Q treatment groupActive comparatorFor 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) groupActive comparatorFor 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.

  1. Postoperative Q value

    Pentacam evaluation of post-LASIK Q value

    Measured: 6 months

Secondary outcomes (1)
  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.

  1. First posted4 Feb 2021
  2. Study start1 Jun 2020
  3. Primary completion30 Jun 2021
  4. Study completion30 Jun 2021

Resources

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)
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 28187180
  • Mostafa 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

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.

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