Astigmatism, Cornea
Conditions
Keywords
Corneal Astigmatism, Scheimpflug, pupil size, Toric
Brief summary
To analyze the difference between measured total corneal astigmatism and actual corneal astigmatism under different region modes and optimize the region setting.
Interventions
OTHERpatients 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.
Sponsors
Wenzhou Medical University
Study design
Observational model
CASE_ONLY
Time perspective
CROSS_SECTIONAL
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
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;
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Vectorial difference | ≥1 month after surgery | The vectorial difference between measured corneal astigmatism (under multiple different region mode settings) and actual corneal astigmatism. |
| pupil size | ≥1 month after surgery | pupil size of patients in a bright environment measured by itrace device and MONCV3 device |
| pupil size 2 | ≥1 month after surgery | pupil size of patients measured by Pentacam HR device |
| residual astigmatism | ≥1 month after surgery | residual astigmatism tested by subjective refraction |
| total corneal astigmatism | ≥1 month after surgery | Total corneal astigmatism measured by a scheimpflug tomographer under different region mode settings. |
| Anterior chamber depth | ≥1 month after surgery | The distance between corneal apex and anterior surface of IOL measured by a scheimpflug tomographer |
| 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. |
Countries
China
Contacts
CONTACTAYong Yu, MD.PhD.
CONTACTXu Shao, MD
PRINCIPAL_INVESTIGATORAYong Yu, MD.PhD.
Wenzhou Medical University
Outcome results
None listed