High MyopiaNCT03394300
Accuracy of Intraocular Lens Power in High Myopia
An observational study of High Myopia, run by Assiut University.
Trial summary
evaluation of the accuracy of iol power in high myopia using different biometry formula \& iol master Read more about this study
- Who is it for?
- Ages 30 to 60 years
- Conditions the study is for
- High Myopia
- What is being tested?
- iol power calculation
- How many people
- 30 participants
- Where
- No sites listed yet
- Study dates
- 1 Feb 2018to 1 Feb 2019
- How long will I take part?
- 1 Year
- Phase
- Observational
- 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 30 to 60 years
- All sexes
- Adult
Study population: data will be collected from all patients who meet inclusion criteria
Who may be able to join
- 1- patients with clear lense extraction or cataract \& high myope with{ AL more than 26 mm.
- 2-their IOLpower is less than 15 diopter or their refraction before operation is more than -6.
Who cannot join
- Keratoconus patients or those with irregular cornea
- Patients with post operative complications like posterior capsule injury or vitrous loss.
- patients who had undergone previous intraocular surgery at anterior segment or posterior segment.
About this study
evaluation of the accuracy of iol power in high myopia using different biometry formula \& iol master
Read the detailed description
High myopia or pathological myopia is associated with elongation of axial length longer than 26 mm or refractive error at least-6 diopter.
High myopia is one of the most prevalent refractive condition globally with a higher risk of other eye conditions Moreover in high myopic eyes the incidence of cataract is significantly higher than in non myopic eyes and the progression is also faster.
Calculation of IOL in high myopic eyes remains a challenge often leading to unexpected postoperative hyperopia the main potential sources of errors in IOL calculation for high myopic eyes include AL measurement \& IOL constants used \&IOL power calculation formula used.
investigators suspect that the SRK I1 formula is inaccurate for myopic eyes, and that new formulas are needed, taking into account all those factors that make up the dioptric power of an eye.
Formulas for IOL power calculation had past four generations, first generation formulas were theoretical and based on the same fundamental constant with no respect to anterior chamber depth. Since then, Binkhorst, Holladay, Hoffer and Shammas had refined the existing theoretical formulas where each of them developed his regression formula based on analysis of their previous IOL cases .
This work was amalgamated in 1980 and yielded the Sanders Retzlaff Kraff I (SRKI) formula The second generation was designed by combining linear regression analysis and stepwise adjustment for long and short eyes according to anterior chamber depth .
The third and fourth generation formulas, started by Holladay in 1988, all aimed at better calculation of the IOL power in eyes with extreme axial length where another term had appeared which is IOL specific anterior chamber depth .
The accuracy of third and fourth generation formulas for IOL calculation in patients with high axial myopia had not been fully evaluated For that, the need for more studies conducted to evaluate such accuracy is crucial.
This study will be conducted to evaluate the accuracy of different formulas used for IOL power calculation in patients with high axial myopia undergoing cataract surgery
- Conditions
- High Myopia
- Being tested
- iol power calculation
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
iol power calculationOther
iol power calculation in high myopia
What is being measured
The primary outcome is the main question the study is designed to answer.
accuracy of iol power in high myopia
biometry assment of IOLpower
Measured: one year
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted9 Jan 2018
- Study start1 Feb 2018 (estimated)
- Primary completion1 Feb 2019 (estimated)
- Study completion1 Feb 2019 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for High MyopiaStudies 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
- Observational
- Observational model
- Case crossover
- Time perspective
- Prospective
- Enrolment
- 30 participants (estimated)
- Target duration
- 1 Year
Sponsor and investigators
- Lead sponsor
- Assiut University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, salma safwat abdelhady mangora, Assiut University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03394300
- Sponsor's protocol ID
- 29110202500209
- Status last verified
- Jan 2018
- First submitted
- 29 Dec 2017
- Last updated
- 9 Jan 2018
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided: Evaluation of accuracy of IOL power calculation in high myopia.
Study at a glance
From the registry record, last updated by the sponsor on 9 Jan 2018. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Accuracy of Intraocular Lens Power in High Myopia
- ClinicalTrials.gov ID
- NCT03394300
- Acronym / sponsor ID
- 29110202500209
- Conditions
- High Myopia
- Study type
- Observational
- Recruitment status
- Unknown status
- Enrolment
- 30 participants (estimated)
- Lead sponsor
- Assiut UniversityUniversity, hospital or other
- Study start
- 1 Feb 2018 (estimated)
- Primary completion
- 1 Feb 2019 (estimated)
- Study completion
- 1 Feb 2019 (estimated)
- First posted
- 9 Jan 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.
evaluation of the accuracy of iol power in high myopia using different biometry formula \& iol master
Detailed description
High myopia or pathological myopia is associated with elongation of axial length longer than 26 mm or refractive error at least-6 diopter.
High myopia is one of the most prevalent refractive condition globally with a higher risk of other eye conditions Moreover in high myopic eyes the incidence of cataract is significantly higher than in non myopic eyes and the progression is also faster.
Calculation of IOL in high myopic eyes remains a challenge often leading to unexpected postoperative hyperopia the main potential sources of errors in IOL calculation for high myopic eyes include AL measurement \& IOL constants used \&IOL power calculation formula used.
investigators suspect that the SRK I1 formula is inaccurate for myopic eyes, and that new formulas are needed, taking into account all those factors that make up the dioptric power of an eye.
Formulas for IOL power calculation had past four generations, first generation formulas were theoretical and based on the same fundamental constant with no respect to anterior chamber depth. Since then, Binkhorst, Holladay, Hoffer and Shammas had refined the existing theoretical formulas where each of them developed his regression formula based on analysis of their previous IOL cases .
This work was amalgamated in 1980 and yielded the Sanders Retzlaff Kraff I (SRKI) formula The second generation was designed by combining linear regression analysis and stepwise adjustment for long and short eyes according to anterior chamber depth .
The third and fourth generation formulas, started by Holladay in 1988, all aimed at better calculation of the IOL power in eyes with extreme axial length where another term had appeared which is IOL specific anterior chamber depth .
The accuracy of third and fourth generation formulas for IOL calculation in patients with high axial myopia had not been fully evaluated For that, the need for more studies conducted to evaluate such accuracy is crucial.
This study will be conducted to evaluate the accuracy of different formulas used for IOL power calculation in patients with high axial myopia undergoing cataract surgery
Study design
- Observational model
- Case crossover
- Time perspective
- Prospective
- Target follow-up
- 1 Year
Who may qualify
- Ages
- 30 to 60 years
- Sex
- All
- Age groups
- Adult
- Study population
- data will be collected from all patients who meet inclusion criteria
Key inclusion criteria (2 listed)
- 1- patients with clear lense extraction or cataract \& high myope with{ AL more than 26 mm.
- 2-their IOLpower is less than 15 diopter or their refraction before operation is more than -6.
Key exclusion criteria (3 listed)
- Keratoconus patients or those with irregular cornea
- Patients with post operative complications like posterior capsule injury or vitrous loss.
- patients who had undergone previous intraocular surgery at anterior segment or posterior segment.
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 |
|---|---|---|
| iol power calculationiol power calculation in high myopia | Other | – |
Primary outcome
accuracy of iol power in high myopia
Time frame: one year
biometry assment of IOLpower
Results and safety
Results are not available in the source record.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 9 Jan 2018.
- Individual participant dataSharing planned: Undecided. Evaluation of accuracy of IOL power calculation in high myopia.
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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.
Questions about this trial
What is this clinical trial studying?
An observational study of High Myopia, run by Assiut University.
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 3 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: status not confirmed, as of the sponsor's last update on 9 Jan 2018. Status can change between updates, so confirm with the study contact before making plans.
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?
Results are not available in the source record.
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?
accuracy of iol power in high myopia (time frame: one year). 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 9 Jan 2018.