The Long-term Outcome After Toric Intraocular Lens Implantation

Study Overview
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Brief Summary
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Corneal astigmatism is refractive error that impairs uncorrected visual acuity. When patients undergo cataract surgery, implantation of toric IOL is deemed the most effective choice for correcting corneal astigmatism and reducing postoperative spectacle dependence. Previous studies report that the visual effects and rotational stability of toric IOLs are well maintained over 1- or 2-year follow-up periods. However, the long-term changes in the effects of toric IOLs remain unclear.

Detailed Description
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Corneal astigmatism is refractive error that impairs uncorrected visual acuity. When patients undergo cataract surgery, implantation of toric IOL is deemed the most effective choice for correcting corneal astigmatism and reducing postoperative spectacle dependence. Previous studies report that the visual effects and rotational stability of toric IOLs are well maintained over 1- or 2-year follow-up periods. However, there is a long-term against-the-rule (ATR) change of corneal astigmatism with aging，which influences the long-term outcomes of refractive surgery. The long-term changes in the effects of toric IOLs remain unclear. This study aim to observe the clinical effect of Toric IOL implantation in the correction of corneal astigmatism.

Official Title
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The Long-term Outcome After Cataract Surgery With Toric Intraocular Lens Implantation

Conditions
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Corneal Astigmatism, Cataract

Intervention / Treatment
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* Device: subjective refraction


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ≥18years old Regular astigmatism Corneal astigmatism ≥ 0.75D Exclusion Criteria: Macular degeneration and retinal disease, history of glaucoma, corneal disease Previous corneal or intraocular surgery, and history of ocular inflammation. Pupils can not be dilated (< 7mm)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Toric IOL<br>This study included the patients who underwent cataract surgery with the toric IOL(SN6ATX) implantation. Preoperative and postoperative corneal astigmatism, short-term and long-term postoperative total astigmatism were the main outcome indicators. Preoperative corneal astigmatism (Pentacam and IOLMaster) would be obtained from outpatient and inpatient medical records, and the IOL axis should be calculated before surgery. Short-term postoperative (1-3 months) subjective optometry results; Long-term postoperative (3-5 years) corneal astigmatism (Pentacam and IOLMaster), subjective optometry results, and axial lens would be observed using SSOCT after pupil dilation. | Device: subjective refraction<br>* Short-term postoperative (1-3 months) and long-term postoperative (3-5 years) subjective optometry results were measured by subjective refraction.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| changes of magnitude of corneal astigmatism from pre-surgery to 3-5 years after surgery | using Pentacam measure cornea astigmatism of the subjects | before surgery and 3-5 years after surgery | 
| changes of axis of corneal astigmatism from pre-surgery to 3-5 years after surgery | using Pentacam measure cornea astigmatism of the subjects | before surgery and 3-5 years after surgery | 
| changes of manifest refractive astigmatism from1 -3 months after surgery to 3-5 years after surgery | measured using subjective refraction by Professional optometrists | 1-3 months after surgery and 3-5 years after surgery |