AstigmatismNCT03299530
Accuracy of Corneal Astigmatism in Different Region Modes
An observational study of Astigmatism and Cornea, run by Wenzhou Medical University at 1 site in China.
Trial summary
To analyze the difference between measured total corneal astigmatism and actual corneal astigmatism under different region modes and optimize the region setting. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Astigmatism, Cornea
- What is being tested?
- patients with corneal astigmatism
- How many people
- 70 participants
- Where
- 1 siteChina
- Study dates
- 10 Oct 2017to 28 Oct 2027
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
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
Study population: Patients who received cataract surgery in The Eye Hospital of Wenzhou Medical University
Who may be able to join
- Age ≥ 18 years
- Patients who had received phacoemulsification surgery with or without implantation of toric IOL are with a certain amount of corneal astigmatism.
- Best corrected visual acuity ≥ 0.66 (20/30 Snellen)
Who cannot join
- Corneal diseases or severe irregular astigmatism (e.g., pterygium, keratoconus), existence of corneal opacification;
- Ocular disease which may affect visual acuity (e.g., glaucoma, uveitis, retinal disease, pathologic myopia);
- History of ocular surgery or ocular trauma before this cataract surgery;
- Decentration of IOL > 0.3mm or tilt > 5°
- Implantation of multifocal IOL
- history of wearing of rigid contact lens within the past 4 weeks or soft contact lens within 1 week;
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Xu Shao, MD contact
China1 site, 1 recruiting
- Recruiting
Eye Hispital of Wenzhou Medical University
Wenzhou, Zhejiang, 325000
About this study
To analyze the difference between measured total corneal astigmatism and actual corneal astigmatism under different region modes and optimize the region setting.
- Conditions
- Astigmatism, Cornea
- Being tested
- patients with corneal astigmatism
- Keywords
- Corneal Astigmatism, Scheimpflug, pupil size, Toric
- Medical subject headings
- Astigmatism, Corneal Diseases
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
patients with corneal astigmatismOther
The total corneal astigmatism, anterior chamber depth, will be measured by a Scheimpflug tomographer. Pupil size will be measured by itrace device and MONCV3 device. Residual astigmatism will be tested by subjective refraction.
| Study group | Role | What they receive |
|---|---|---|
| patients with corneal astigmatism | Patients who had received phacoemulsification surgery with or without implantation of toric IOL are with a certain amount of corneal astigmatism. Receives: Other: patients with corneal astigmatism |
What is being measured
The primary outcome is the main question the study is designed to answer.
Vectorial difference
The vectorial difference between measured corneal astigmatism (under multiple different region mode settings) and actual corneal astigmatism.
Measured: ≥1 month after surgery
pupil size
pupil size of patients in a bright environment measured by itrace device and MONCV3 device
Measured: ≥1 month after surgery
pupil size 2
pupil size of patients measured by Pentacam HR device
Measured: ≥1 month after surgery
residual astigmatism
residual astigmatism tested by subjective refraction
Measured: ≥1 month after surgery
total corneal astigmatism
Total corneal astigmatism measured by a scheimpflug tomographer under different region mode settings.
Measured: ≥1 month after surgery
Anterior chamber depth
The distance between corneal apex and anterior surface of IOL measured by a scheimpflug tomographer
Measured: ≥1 month after surgery
actual corneal astigmatism
actual corneal astigmatism is derived from residual astigmatism at corneal plane and cylindrical power of IOL at corneal plane through Holladay 2 formula.
Measured: ≥1 month after surgery
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted3 Oct 2017
- Study start10 Oct 2017
- Primary completion10 Jun 2027 (estimated)
- Study completion28 Oct 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for AstigmatismStudies 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
- Observational
- Observational model
- Case only
- Time perspective
- Cross-sectional
- Enrolment
- 70 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Wenzhou Medical University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, A-Yong Yu, Wenzhou Medical University
- Investigators
- AYong Yu, MD.PhD., Principal investigator, Wenzhou Medical University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03299530
- Sponsor's protocol ID
- 2017ASTIGMATISM REGIONS
- Status last verified
- Aug 2026
- First submitted
- 27 Sep 2017
- Last updated
- 19 Aug 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 19 Aug 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Accuracy of Corneal Astigmatism in Different Region Modes
- ClinicalTrials.gov ID
- NCT03299530
- Acronym / sponsor ID
- 2017ASTIGMATISM REGIONS
- Conditions
- Astigmatism, Cornea
- Keywords
- Corneal Astigmatism, Scheimpflug, pupil size, Toric
- Study type
- Observational
- Recruitment status
- Recruiting
- Enrolment
- 70 participants (estimated)
- Lead sponsor
- Wenzhou Medical UniversityUniversity, hospital or other
- Study start
- 10 Oct 2017 (actual)
- Primary completion
- 10 Jun 2027 (estimated)
- Study completion
- 28 Oct 2027 (estimated)
- First posted
- 3 Oct 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.
To analyze the difference between measured total corneal astigmatism and actual corneal astigmatism under different region modes and optimize the region setting.
Study design
- Observational model
- Case only
- Time perspective
- Cross-sectional
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| patients with corneal astigmatism | – | Other: patients with corneal astigmatismPatients who had received phacoemulsification surgery with or without implantation of toric IOL are with a certain amount of corneal astigmatism. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Patients who received cataract surgery in The Eye Hospital of Wenzhou Medical University
Key inclusion criteria (3 listed)
- Age ≥ 18 years
- Patients who had received phacoemulsification surgery with or without implantation of toric IOL are with a certain amount of corneal astigmatism.
- Best corrected visual acuity ≥ 0.66 (20/30 Snellen)
Key exclusion criteria (6 listed)
- Corneal diseases or severe irregular astigmatism (e.g., pterygium, keratoconus), existence of corneal opacification;
- Ocular disease which may affect visual acuity (e.g., glaucoma, uveitis, retinal disease, pathologic myopia);
- History of ocular surgery or ocular trauma before this cataract surgery;
- Decentration of IOL > 0.3mm or tilt > 5°
- Implantation of multifocal IOL
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 |
|---|---|---|
| patients with corneal astigmatismThe total corneal astigmatism, anterior chamber depth, will be measured by a Scheimpflug tomographer. Pupil size will be measured by itrace device and MONCV3 device. Residual astigmatism will be tested by subjective refraction. | Other | patients with corneal astigmatism |
Primary outcome
Vectorial difference
Time frame: ≥1 month after surgery
The vectorial difference between measured corneal astigmatism (under multiple different region mode settings) and actual corneal astigmatism.
pupil size
Time frame: ≥1 month after surgery
pupil size of patients in a bright environment measured by itrace device and MONCV3 device
pupil size 2
Time frame: ≥1 month after surgery
pupil size of patients measured by Pentacam HR device
residual astigmatism
Time frame: ≥1 month after surgery
residual astigmatism tested by subjective refraction
total corneal astigmatism
Time frame: ≥1 month after surgery
Total corneal astigmatism measured by a scheimpflug tomographer under different region mode settings.
Anterior chamber depth
Time frame: ≥1 month after surgery
The distance between corneal apex and anterior surface of IOL measured by a scheimpflug tomographer
actual corneal astigmatism
Time frame: ≥1 month after surgery
actual corneal astigmatism is derived from residual astigmatism at corneal plane and cylindrical power of IOL at corneal plane through Holladay 2 formula.
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 19 Aug 2026.
- Individual participant dataSharing planned: No
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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.
Xu Shao, MD contact
AYong Yu, MD.PhD. principal investigator
Wenzhou Medical University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Astigmatism and Cornea, run by Wenzhou Medical University at 1 site in China.
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 6 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: looking for participants now, as of the sponsor's last update on 19 Aug 2026. 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 China. 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?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact AYong Yu, MD.PhD. (+86-0577-88068880, yaybetter@hotmail.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Vectorial difference (time frame: ≥1 month after surgery). 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 19 Aug 2026.