Myopic LASIK Candidates With Spherical Equivalent up to - 10 DioptersNCT04831177
Thin-Flap Laser in Situ Keratomileusis Associated Dry Eye
A study testing Laser in situ keratomileusis in people with Myopic LASIK Candidates With Spherical Equivalent up to - 10 Diopters, run by Assiut University at 1 site in Egypt.
Trial summary
Laser in situ keratomileusis (LASIK) eye surgery continues to be the most common refractive procedure used to correct different forms of ametropia. Although the introduction of femtosecond technology has markedly reduced the incidence of intraoperative flap complications and allowed a better control on flap… Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Myopic LASIK Candidates With Spherical Equivalent up to - 10 Diopters
- What is being tested?
- Laser in situ keratomileusis
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 55 participants
- Where
- 1 siteEgypt
- Study dates
- 1 Jun 2019to 1 Sep 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
- Candidates for Laser Vision Correction (LVC).
- Eyes with spherical equivalent (SE) up to - 10 diopters (D),
- Corneal thickness at thinnest location of ≥ 500 um and estimated postoperative residual stromal bed of at least 300 um
Who cannot join
- Patients with symptoms or signs of dry eye (TBUT <10 sec, Schirmer I test <10mm and Ocular Surface Disease Index OSDI score >13),
- Posterior blepharitis, contact lens wearers ,
- Ocular surface disease ,
- Systemic diseases contraindicating LASIK and previous ocular surgery.
Trial locations and contacts
1 site in 1 country.
About this study
Laser in situ keratomileusis (LASIK) eye surgery continues to be the most common refractive procedure used to correct different forms of ametropia. Although the introduction of femtosecond technology has markedly reduced the incidence of intraoperative flap complications and allowed a better control on flap parameters, dry eye remains one of the most challenging postoperative complications.
Read the detailed description
The pathophysiology of post LASIK dry eye is not clear; however, many mechanisms have been suggested including inflammation, loss of conjunctival goblet cells during suction, exacerbation of a preexisting dry eye, abnormal interaction between the lid margins and the ocular surface. Intact corneal sensation is crucial for proper tear production and distribution on the ocular surface as well as maintaining the normal dynamics of eyelid blinking. Disruption of corneal nerves in LASIK decreases the release of neurotrophic factors necessary for the normal function of the corneal epithelium as well as the integrity of the lacrimal functional unit, a condition referred to as LASIK induced neurotrophic epitheliopathy (LINE) that largely contributes to the development of post- LASIK dry eye .
Many studies evaluated the incidence of post-refractive dry eye after LASIK compared to flapless laser vision correction (LVC) procedures such as PRK and small incision lenticule extraction (SMILE). The aim of this study is to assess and compare different dry eye parameters following LASIK with planned thin flaps created by femtosecond laser (FS) and mechanical microkeratome (MK).
- Being tested
- Laser in situ keratomileusis
- Keywords
- Dry eye, Femtolaser, Laser in situ keratomileusis
- Medical subject headings
- Dry Eye Syndromes
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Laser in situ keratomileusisProcedure or surgery
Laser in situ keratomileusis LASIK is a procedure used to correct different types of ametropia through a creation of corneal flap whether with femtosecond laser or mechanically with a microkeratome followed by application of excimer laser to correct different refractive errors including Myopia, Hyperopia and Astigmatism.
| Study group | Role | What they receive |
|---|---|---|
| Patients planned to undergo Femtosecond laser FS assisted LASIK | Active comparator | In FS group, Allegretto WaveLight FS-200 femtosecond laser was used to create flaps with flap thickness planned to be 100 um. Receives: Procedure: Laser in situ keratomileusis |
| Patients planned to undergo Microkeratome MK assisted LASIK | Active comparator | In MK group, Moria 2 Microkeratome was used to create flaps with flap thickness planned to be 100 um. Receives: Procedure: Laser in situ keratomileusis |
What is being measured
The primary outcome is the main question the study is designed to answer.
Tear film break up time TBUT
Fluorescein strip was inserted in the lower conjunctival fornix for few seconds then removed and the patient was asked to frequently blink, the stained tear film was observed with slit lamp (cobalt blue filter) till the appearance of the first black (dry) spot and the time interval in seconds was measured
Measured: 6 months
Schirmer I test
Whatman filter paper (35 mm long) was folded 5mm and inserted in the lower conjunctival fornix away from the cornea and the patient was asked to blink normally. After 5minutes the paper was removed, and the amount of wetting in millimeters was measured.
Measured: 6 months
Ocular Surface Disease Index OSDI
A questionnaire consisting of 12 questions. Each question with a score from 0 to 4, the OSDI score is calculated by multiplying the sum by 25 and dividing by the number of questions answered. This yields a score from 0 to 100. The results of OSDI score can be graded as normal (0-12), mild dry eye (13-22), moderate dry eye (23-32), or severe dry eye (33-100)
Measured: 6 months
Lower Tear meniscus height (LTMH)
Anterior segment Optical coherence tomography (AS-OCT) examination was scheduled in the afternoon. The lower TMH was evaluated with a vertical scan centered on the inferior cornea and the lower eyelid. The lower TMH was measured with a special caliper tool incorporated in the device in micrometers and the height of the tear meniscus is the distance between 2 points ,one where the meniscus intersects the inferior cornea superiorly and the other where the meniscus intersects the lower eyelid margin inferiorly.
Measured: 6 months
Lower Tear meniscus area (LTMA)
The lower TMA was evaluated using AS-OCT with a vertical scan centered on the inferior cornea and the lower eyelid then a built in software caliper tool was used to determine the borders of the tear meniscus and calculate the area (TMA) in millimeter square (mm2).
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 posted5 Apr 2021
- Study start1 Jun 2019
- Primary completion1 Sep 2020
- Study completion1 Sep 2020
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 Myopic LASIK Candidates With Spherical Equivalent up to - 10 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
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind
- Who is masked
- Outcomes assessor
- Enrolment
- 55 participants (actual)
Sponsor and investigators
- Lead sponsor
- Assiut University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Mahmoud Abdel-Radi, Assiut University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04831177
- Sponsor's protocol ID
- TFLADE
- Status last verified
- Apr 2021
- First submitted
- 31 Mar 2021
- Last updated
- 6 Apr 2021
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Sambhi RS, Sambhi GDS, Mather R, Malvankar-Mehta MS. Dry eye after refractive surgery: a meta-analysis. Can J Ophthalmol. 2020 Apr;55(2):99-106. doi: 10.1016/j.jcjo.2019.07.005. Epub 2019 Aug 20.
PubMed 31712000
Study at a glance
From the registry record, last updated by the sponsor on 6 Apr 2021. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Thin-Flap Laser in Situ Keratomileusis Associated Dry Eye
- ClinicalTrials.gov ID
- NCT04831177
- Acronym / sponsor ID
- TFLADE
- Keywords
- Dry eye, Femtolaser, Laser in situ keratomileusis
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 55 participants (actual)
- Lead sponsor
- Assiut UniversityUniversity, hospital or other
- Study start
- 1 Jun 2019 (actual)
- Primary completion
- 1 Sep 2020 (actual)
- Study completion
- 1 Sep 2020 (actual)
- First posted
- 5 Apr 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.
Laser in situ keratomileusis (LASIK) eye surgery continues to be the most common refractive procedure used to correct different forms of ametropia. Although the introduction of femtosecond technology has markedly reduced the incidence of intraoperative flap complications and allowed a better control on flap parameters, dry eye remains one of the most challenging postoperative complications.
Detailed description
The pathophysiology of post LASIK dry eye is not clear; however, many mechanisms have been suggested including inflammation, loss of conjunctival goblet cells during suction, exacerbation of a preexisting dry eye, abnormal interaction between the lid margins and the ocular surface. Intact corneal sensation is crucial for proper tear production and distribution on the ocular surface as well as maintaining the normal dynamics of eyelid blinking. Disruption of corneal nerves in LASIK decreases the release of neurotrophic factors necessary for the normal function of the corneal epithelium as well as the integrity of the lacrimal functional unit, a condition referred to as LASIK induced neurotrophic epitheliopathy (LINE) that largely contributes to the development of post- LASIK dry eye .
Many studies evaluated the incidence of post-refractive dry eye after LASIK compared to flapless laser vision correction (LVC) procedures such as PRK and small incision lenticule extraction (SMILE). The aim of this study is to assess and compare different dry eye parameters following LASIK with planned thin flaps created by femtosecond laser (FS) and mechanical microkeratome (MK).
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Patients planned to undergo Femtosecond laser FS assisted LASIK | Active comparator | Procedure: Laser in situ keratomileusisIn FS group, Allegretto WaveLight FS-200 femtosecond laser was used to create flaps with flap thickness planned to be 100 um. |
| Patients planned to undergo Microkeratome MK assisted LASIK | Active comparator | Procedure: Laser in situ keratomileusisIn MK group, Moria 2 Microkeratome was used to create flaps with flap thickness planned to be 100 um. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (3 listed)
- Candidates for Laser Vision Correction (LVC).
- Eyes with spherical equivalent (SE) up to - 10 diopters (D),
- Corneal thickness at thinnest location of ≥ 500 um and estimated postoperative residual stromal bed of at least 300 um
Key exclusion criteria (4 listed)
- Patients with symptoms or signs of dry eye (TBUT <10 sec, Schirmer I test <10mm and Ocular Surface Disease Index OSDI score >13),
- Posterior blepharitis, contact lens wearers ,
- Ocular surface disease ,
- Systemic diseases contraindicating LASIK and previous ocular 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 |
|---|---|---|
| Laser in situ keratomileusisLaser in situ keratomileusis LASIK is a procedure used to correct different types of ametropia through a creation of corneal flap whether with femtosecond laser or mechanically with a microkeratome followed by application of excimer laser to correct different refractive errors including Myopia, Hyperopia and Astigmatism. | Procedure or surgery | Patients planned to undergo Femtosecond laser FS assisted LASIK, Patients planned to undergo Microkeratome MK assisted LASIK |
Primary outcome
Tear film break up time TBUT
Time frame: 6 months
Fluorescein strip was inserted in the lower conjunctival fornix for few seconds then removed and the patient was asked to frequently blink, the stained tear film was observed with slit lamp (cobalt blue filter) till the appearance of the first black (dry) spot and the time interval in seconds was measured
Schirmer I test
Time frame: 6 months
Whatman filter paper (35 mm long) was folded 5mm and inserted in the lower conjunctival fornix away from the cornea and the patient was asked to blink normally. After 5minutes the paper was removed, and the amount of wetting in millimeters was measured.
Ocular Surface Disease Index OSDI
Time frame: 6 months
A questionnaire consisting of 12 questions. Each question with a score from 0 to 4, the OSDI score is calculated by multiplying the sum by 25 and dividing by the number of questions answered. This yields a score from 0 to 100. The results of OSDI score can be graded as normal (0-12), mild dry eye (13-22), moderate dry eye (23-32), or severe dry eye (33-100)
Lower Tear meniscus height (LTMH)
Time frame: 6 months
Anterior segment Optical coherence tomography (AS-OCT) examination was scheduled in the afternoon. The lower TMH was evaluated with a vertical scan centered on the inferior cornea and the lower eyelid. The lower TMH was measured with a special caliper tool incorporated in the device in micrometers and the height of the tear meniscus is the distance between 2 points ,one where the meniscus intersects the inferior cornea superiorly and the other where the meniscus intersects the lower eyelid margin inferiorly.
Lower Tear meniscus area (LTMA)
Time frame: 6 months
The lower TMA was evaluated using AS-OCT with a vertical scan centered on the inferior cornea and the lower eyelid then a built in software caliper tool was used to determine the borders of the tear meniscus and calculate the area (TMA) in millimeter square (mm2).
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 6 Apr 2021.
- Background: PubMed 31712000Sambhi RS, Sambhi GDS, Mather R, Malvankar-Mehta MS. Dry eye after refractive surgery: a meta-analysis. Can J Ophthalmol. 2020 Apr;55(2):99-106. doi: 10.1016/j.jcjo.2019.07.005. Epub 2019 Aug 20.
- 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.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Laser in situ keratomileusis in people with Myopic LASIK Candidates With Spherical Equivalent up to - 10 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 3 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 6 Apr 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?
Tear film break up time TBUT (time frame: 6 months). The study lists 5 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 NCT04831177, 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 Apr 2021.