Prospective Clinical Study of Preoperative and Postoperative Unilateral Mild Cataract Patients

Study Overview
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Brief Summary
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This is to compare preoperative and postoperative binocular functional vision in patients with unilateral intraocular len（IOL） in one eye and mild cataract in the fellow eye.

Detailed Description
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The subjects are the patients who underwent monocular IOL implantation before and present mild cataract in the fellow eye.Compare preoperative and postoperative the binocular functional vision and the satisfaction of patients when the patients ask for the surgery (phacoemulsification and IOLs implantation)on the fellow eye. The type of IOLs maybe according to the patients preference and the eyes condition.The subjects will be divided into three groups according to the type of the IOLs，including monofocal group,bifocal group,and trifocal group.

Official Title
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Prospective Clinical Study of Preoperative and Postoperative Unilateral Mild Cataract Patients

Conditions
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Cataract Senile

Intervention / Treatment
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* Device: monofocal IOL,bifocal IOL,or trifocal IOL


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients who had monocular intraocular lens in one eye with mild cataract in the fellow eye ask for the cataract surgery in the fellow eye Regular corneal topography and corneal astigmatism ≤ 0.75 Diopter Exclusion Criteria: Pregnant or nursing women In the presence of other ocular diseases that may affect the stability of the lens capsule (pseudoexfoliation syndrome, glaucoma, traumatic cataract, Marfan syndrome, etc.) In the presence of other ocular diseases that is expected to have a poor final visual acuity of worse than 0.2 logMAR after surgery (amblyopia, strabismus, keratoconus, etc.) Pupil abnormality (non-reactive pupil, tonic pupils, abnormally shaped pupils, etc.) Patients using systemic or ocular medication that affect visual acuity. Patients with history of ocular trauma or prior ocular surgery including refractive procedures Patients participating in other clinical trials during the study.

Ages Eligible for Study
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Minimum Age: 50 Years
Maximum Age: 80 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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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: unilateral mild cataract patients<br>The patients who underwent monocular IOL implantation before and then present mild cataract in the fellow eye. | Device: monofocal IOL,bifocal IOL,or trifocal IOL<br>* phacoemulsification and implantation of IOL.IOL may be monofocal IOL,bifocal IOL,or trifocal IOL<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| binocular visual acuity | uncorrected distance visual acuity (UCVA), intermediate visual acuity, near visual acuity will be measured at 5m, 80cm and 40cm respectively. All visual acuity measurements will be conducted under photopic conditions (85 cd/m2) and at 100% contrast | 3 months postoperatively | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Binocular Contrast sensitivity | Contrast sensitivity measures will be conducted binocularly, under photopic, mesopic (5 cd/m2), photopic with glare and mesopic with glare conditions, with the OPTEC 6500 contrast sensitivity test (Stereo Optical, USA). Contrast sensitivity will be evaluated at five spatial frequencies (1.5, 3, 6, 12, and 18 cycles per degree [cpd]). Patients will be allowed 5 minutes to adapt to each illumination level before testing | 3 months postoperatively | 
| Binocular Defocus Curve | Binocular defocus curves will be obtained in all patients, positioned at 5m under photopic (>85 cd/m 2 ) condition to measure the visual acuity with each defocus lens, representing the consecutive visual function of each eye. Negative lenses were added in 0.50 D steps and the visual acuity will be recorded for each type of defocus level. The procedure will be then repeated but with positive lenses. The range of defocus evaluated is from -4.00D to +2.00D. | 3 months postoperatively | 
| stereopsis | Use block diagram of random-spot synoptophore to observe long distance stereopsis vision and yan's stereogram to observe short distance stereopsis vision. | 3 months postoperatively | 
| Fusion function | The fusion function of perception and movement (convergence and divergence)will be examined with a synoptophore. | 3 months postoperatively | 
| Subjective visual quality | Photic phenomena (score according to severity,0 4, higher scores mean worse)and spectacle dependence percentages will be evaluated by questionnaire. | 3 months postoperatively | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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unilateral cataract, binocular functional vision, Multifocal Intraocular Lenses