Accuracy of Corneal Astigmatism in Different Region Modes

Sponsor
Wenzhou Medical University (Other)
Overall Status
Recruiting
CT.gov ID
NCT03299530
Collaborator
(none)
70
1
84.6
0.8

Study Details

Study Description

Brief Summary

To analyze the difference between measured total corneal astigmatism and actual corneal astigmatism under different region modes and optimize the region setting.

Condition or Disease Intervention/Treatment Phase
  • Other: patients with corneal astigmatism

Study Design

Study Type:
Observational
Anticipated Enrollment :
70 participants
Observational Model:
Case-Only
Time Perspective:
Cross-Sectional
Official Title:
Accuracy of Corneal Astigmatism in Different Region Modes
Actual Study Start Date :
Oct 10, 2017
Anticipated Primary Completion Date :
Jun 10, 2024
Anticipated Study Completion Date :
Oct 28, 2024

Arms and Interventions

Arm Intervention/Treatment
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.

Other: patients with corneal astigmatism
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.

Outcome Measures

Primary Outcome Measures

  1. Vectorial difference [≥1 month after surgery]

    The vectorial difference between measured corneal astigmatism (under multiple different region mode settings) and actual corneal astigmatism.

  2. pupil size [≥1 month after surgery]

    pupil size of patients in a bright environment measured by itrace device and MONCV3 device

  3. pupil size 2 [≥1 month after surgery]

    pupil size of patients measured by Pentacam HR device

  4. residual astigmatism [≥1 month after surgery]

    residual astigmatism tested by subjective refraction

  5. total corneal astigmatism [≥1 month after surgery]

    Total corneal astigmatism measured by a scheimpflug tomographer under different region mode settings.

  6. Anterior chamber depth [≥1 month after surgery]

    The distance between corneal apex and anterior surface of IOL measured by a scheimpflug tomographer

  7. actual corneal astigmatism [≥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.

Eligibility Criteria

Criteria

Ages Eligible for Study:
18 Years and Older
Sexes Eligible for Study:
All
Accepts Healthy Volunteers:
No
Inclusion Criteria:
  • 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)

Exclusion Criteria:
  • 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;

Contacts and Locations

Locations

Site City State Country Postal Code
1 Eye Hispital of Wenzhou Medical University Wenzhou Zhejiang China 325000

Sponsors and Collaborators

  • Wenzhou Medical University

Investigators

  • Principal Investigator: AYong Yu, MD.PhD., Wenzhou Medical University

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.
Responsible Party:
A-Yong Yu, Director of the Cataract Clinical Center, Wenzhou Medical University
ClinicalTrials.gov Identifier:
NCT03299530
Other Study ID Numbers:
  • 2017ASTIGMATISM REGIONS
First Posted:
Oct 3, 2017
Last Update Posted:
Jul 13, 2022
Last Verified:
Jul 1, 2022
Individual Participant Data (IPD) Sharing Statement:
No
Plan to Share IPD:
No
Studies a U.S. FDA-regulated Drug Product:
No
Studies a U.S. FDA-regulated Device Product:
No
Keywords provided by A-Yong Yu, Director of the Cataract Clinical Center, Wenzhou Medical University
Additional relevant MeSH terms:

Study Results

No Results Posted as of Jul 13, 2022