MyopiaNCT03291873
Topography-Guided Customized PRK Versus Q-value Adjusted PRK in Correction of Myopia With or Without Astigmatism
A study testing PRK in people with Myopia, run by Kasr El Aini Hospital at 2 sites in Egypt.
Trial summary
This study will include patients who will undergo PRK in both eyes, for each patient each eye will be randomly allocated to one of 2 procedures: topography-guided ablation in one eye (group I) and Q-factor customized ablation in the other eye (group II). Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Myopia
- What is being tested?
- PRK
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 104 participants
- Where
- 2 sitesEgypt
- Study dates
- 25 Oct 2017to 25 Jun 2019
- 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
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Age more than 18 years
- Myopia with up to -6.5 D with or without astigmatism up to -4.75 D
Who cannot join
- anterior segment abnormalities (ie, cataracts, corneal scarring)
- basement membrane disease
- history of recurrent corneal erosions
- Schirmer's test less than 5 mm
- established or forme fruste keratoconus
- macular or retinal disease
Show all 9Show fewer
- current use of immunosuppressive therapy
- autoimmune disease
- pregnancy, and lactation
Trial locations and contacts
2 sites in 1 country.
About this study
Official title: Topography-Guided Customized PRK (Photorefractive Keratectomy) Versus Q-value Adjusted PRK in Correction of Myopia With or Without Astigmatism
This study will include patients who will undergo PRK in both eyes, for each patient each eye will be randomly allocated to one of 2 procedures:
topography-guided ablation in one eye (group I) and Q-factor customized ablation in the other eye (group II).
Alcon/Wavelight Light Laser Technolo¬gie (GmbH, Erlangen, Germany) will be used for photoablation.
The wavelight Topolyzer (Wavelight AG, Erlan¬gen, Germany)and CSO Sirius scheimpflug camera combined with Placido corneal topography (CSO, Florence,Italy) will be used before and 1, 3 and 6 months after PRK. Refrac¬tive visual outcomes and corneal aberration changes will be compared between the two treatment modalities.
- Conditions
- Myopia
- Being tested
- PRK
- Medical subject headings
- Myopia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
PRKProcedure or surgery
PRK using Alcon-Wavelight Excimer Laser EX 500
| Study group | Role | What they receive |
|---|---|---|
| topography guided PRK in one eye | Active comparator | Topography-guided (placido disk- based) using T-CAT Contoura treatment. Receives: Procedure: PRK |
| Q-value adjusted ( custom Q) PRK in the other eye | Active comparator | The target Q will be estimated according to a nomogram considering the patient's age Receives: Procedure: PRK |
What is being measured
The primary outcome is the main question the study is designed to answer.
change in Postoperative spherical equivalent depending on manifest refraction after autorefractometer
Measured: 1 , 3 and 6 months postoperative
change in visual acuity using snellen chart
Measured: 1 , 3 and 6 months postoperative
change in corneal wavefront aberrations
assessed by topolyzer
Measured: 1 , 3 and 6 months postoperative
change in Q value anterior at 6mm RMS, RMS of astigmatism, RMS of coma and RMS of spherical aberrations. Strehl ratio : Qvalue,RMS,strehl ratio by CSO Sirius scheimpflug
by CSO Sirius scheimpflug
Measured: 1,3 and 6months
change in total RMS
by CSO Sirius scheimpflug
Measured: 1,3 and 6months
change in strehl ratio
by CSO scheimpflug
Measured: 1,3 and 6 months
change in Q value
assessed by topolyzer
Measured: 1,3 and 6 months
Secondary outcomes (5)
efficacy:ratio of postoperative decimal UDVA to preoperative decimal CDVA
ratio of postoperative decimal UDVA to preoperative decimal CDVA
Measured: 6 months
contrast sensitivity
cambridge low contrast sensitivity
Measured: 6 months
predictability
eyes within 1.0 D of emmetropia
Measured: 6 months
safety:ratio of mean preoperative decimal CDVA to mean postoperative decimal CDVA
ratio of mean preoperative decimal CDVA to mean postoperative decimal CDVA
Measured: 6 months
stability
change of more than 0.5D over
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 posted25 Sep 2017
- Study start25 Oct 2017
- Primary completion25 Jun 2019
- Study completion25 Jun 2019
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for MyopiaStudies 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
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind
- Who is masked
- Participant
- Enrolment
- 104 participants (actual)
Sponsor and investigators
- Lead sponsor
- Kasr El Aini Hospital
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Rania Elsayed Gad, Kasr El Aini Hospital
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03291873
- Sponsor's protocol ID
- 900800700600500400300200100900
- Status last verified
- Jul 2020
- First submitted
- 8 Aug 2017
- Last updated
- 7 Jul 2020
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 7 Jul 2020. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Topography-Guided Customized PRK (Photorefractive Keratectomy) Versus Q-value Adjusted PRK in Correction of Myopia With or Without Astigmatism
- ClinicalTrials.gov ID
- NCT03291873
- Acronym / sponsor ID
- 900800700600500400300200100900
- Conditions
- Myopia
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 104 participants (actual)
- Lead sponsor
- Kasr El Aini HospitalUniversity, hospital or other
- Study start
- 25 Oct 2017 (actual)
- Primary completion
- 25 Jun 2019 (actual)
- Study completion
- 25 Jun 2019 (actual)
- First posted
- 25 Sep 2017 (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.
This study will include patients who will undergo PRK in both eyes, for each patient each eye will be randomly allocated to one of 2 procedures:
topography-guided ablation in one eye (group I) and Q-factor customized ablation in the other eye (group II).
Alcon/Wavelight Light Laser Technolo¬gie (GmbH, Erlangen, Germany) will be used for photoablation.
The wavelight Topolyzer (Wavelight AG, Erlan¬gen, Germany)and CSO Sirius scheimpflug camera combined with Placido corneal topography (CSO, Florence,Italy) will be used before and 1, 3 and 6 months after PRK. Refrac¬tive visual outcomes and corneal aberration changes will be compared between the two treatment modalities.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (participant)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| topography guided PRK in one eye | Active comparator | Procedure: PRKTopography-guided (placido disk- based) using T-CAT Contoura treatment. |
| Q-value adjusted ( custom Q) PRK in the other eye | Active comparator | Procedure: PRKThe target Q will be estimated according to a nomogram considering the patient's age |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (2 listed)
- Age more than 18 years
- Myopia with up to -6.5 D with or without astigmatism up to -4.75 D
Key exclusion criteria (9 listed)
- anterior segment abnormalities (ie, cataracts, corneal scarring)
- basement membrane disease
- history of recurrent corneal erosions
- Schirmer's test less than 5 mm
- established or forme fruste keratoconus
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 |
|---|---|---|
| PRKPRK using Alcon-Wavelight Excimer Laser EX 500 | Procedure or surgery | Q-value adjusted ( custom Q) PRK in the other eye, topography guided PRK in one eye |
Primary outcome
change in Postoperative spherical equivalent depending on manifest refraction after autorefractometer
Time frame: 1 , 3 and 6 months postoperative
change in visual acuity using snellen chart
Time frame: 1 , 3 and 6 months postoperative
change in corneal wavefront aberrations
Time frame: 1 , 3 and 6 months postoperative
assessed by topolyzer
change in Q value anterior at 6mm RMS, RMS of astigmatism, RMS of coma and RMS of spherical aberrations. Strehl ratio : Qvalue,RMS,strehl ratio by CSO Sirius scheimpflug
Time frame: 1,3 and 6months
by CSO Sirius scheimpflug
change in total RMS
Time frame: 1,3 and 6months
by CSO Sirius scheimpflug
change in strehl ratio
Time frame: 1,3 and 6 months
by CSO scheimpflug
change in Q value
Time frame: 1,3 and 6 months
assessed by topolyzer
5 secondary outcomes
efficacy:ratio of postoperative decimal UDVA to preoperative decimal CDVA
Time frame: 6 months
contrast sensitivity
Time frame: 6 months
predictability
Time frame: 6 months
safety:ratio of mean preoperative decimal CDVA to mean postoperative decimal CDVA
Time frame: 6 months
stability
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 7 Jul 2020.
- Individual participant dataSharing planned: Undecided
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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.
The record lists no contact. Use the official record to reach the sponsor.
2 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing PRK in people with Myopia, run by Kasr El Aini Hospital at 2 sites 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 9 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 7 Jul 2020. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites 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?
change in Postoperative spherical equivalent depending on manifest refraction after autorefractometer (time frame: 1 , 3 and 6 months postoperative). The study lists 7 primary outcomes in all. 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 7 Jul 2020; AzTrials last refreshed its copy on 28 Oct 2026.