IOL-capsular Complex After Different Intraocular Lenses Implantation in Patients With High Myopia

Study Overview
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Brief Summary
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The IOL-capsular complex is formed after cataract surgery and intraocular lens (IOL) implantation. Early postoperative mechanical wrapping of the anterior and posterior capsules plays a significant role in preventing IOL decentration and tilt, as well as formation of the IOL-capsular complex which reduces the incidence of posterior cataract opacity. IOL decentration ≥ 0.4 mm or/and IOL tilt ≥7degree were considered clinically significant cause of poor post-surgery visual quality especially for optical sophisticated IOLs. This negative impact does not affect various types of IOLs equally. Several studies indicated that AL was an independent risk factor of IOL decentration and tilt for emmetropic or moderate myopic eyes. For patients with high myopia, they often have a longer axial length and a larger capsule diameter, which reduces the rotational stability of the IOL and may lead to tilt, decentration and displacement of IOL. Currently, there is no literature guidance to compare the results of cataract surgery combined various types of IOLs implantation in patients with high myopia. The novel anterior segment optical coherence tomography (AS-OCT) device, CASIA2 can evaluate the IOL capsule bending and the lens position after cataract surgery. Also, CASIA2 can be used to documented the dynamic changes of IOL-capsular complex after surgery.

Detailed Description
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The IOL-capsular complex is formed after cataract surgery and intraocular lens (IOL) implantation. Early postoperative mechanical wrapping of the anterior and posterior capsules plays a significant role in preventing IOL decentration and tilt, as well as formation of the IOL-capsular complex which reduces the incidence of posterior cataract opacity. Although up to 2-3 degree tilt and a 0.2-0.3 mm decentration are common and clinically unnoticed for any design of IOL, larger extent of tilt and decentration has a negative impact on the optical performance. IOL decentration ≥ 0.4 mm or/and IOL tilt ≥7degree were considered clinically significant cause of poor post-surgery visual quality especially for optical sophisticated IOLs. This negative impact does not affect various types of IOLs equally. Several studies indicated that AL was an independent risk factor of IOL decentration and tilt for emmetropic or moderate myopic eyes. However, there is scarce evidence on characteristics and factors associated with clinically significant IOL decentration and tilt in highly myopic eyes. For patients with high myopia, they often have a longer axial length and a larger capsule diameter, which reduces the rotational stability of the IOL and may lead to tilt, decentration and displacement of IOL. Currently, there is no literature guidance to compare the results of cataract surgery combined various types of IOLs implantation in patients with high myopia. The novel anterior segment optical coherence tomography (AS-OCT) device, CASIA2 can evaluate the IOL capsule bending and the lens position after cataract surgery. Also, CASIA2 can be used to documented the dynamic changes of IOL-capsular complex after surgery.

Official Title
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Influence of Different Intraocular Lenses on IOL-capsular Complex After Cataract Surgery in Patients With High Myopia: a Clinical Observation Based on SS-OCT

Conditions
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Age-related Cataract

Intervention / Treatment
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* Procedure: one-piece
* Procedure: plate-haptic


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: The patients are diagnosed age related cataract or complicated cataract with axial length over 26mm The patients' age over 18 years old The patients plan to receive cataract surgery in Eye hospital of Wenzhou Medical University The dialated pupils are over 6mm Patients are willing and able to complete the follow-ups Exclusion Criteria: Patients with other types of cataract Patients have complications in the surgery and after surgery Patients have other severe diseases of eyes

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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: one-piece<br>The patients' axial length is over 26 mm and are diagnosed age related cataract or complicated cataract. | Procedure: one-piece<br>* Patients underwent phacoemulsification cataract surgery with one-piece IOL implantation.<br>|
| Experimental: plate-haptic<br>The patients' axial length is over 26 mm and are diagnosed age related cataract or complicated cataract. | Procedure: plate-haptic<br>* Patients underwent phacoemulsification cataract surgery with plate-haptic IOL implantation.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The position of IOL | Evaluation of the position of IOL through tilt, decentration and the process of capsule bending using CASIA2. | The 1st day after surgery | 
| The position of IOL | Evaluation of the position of IOL through tilt, decentration and the process of capsule bending using CASIA2. | The 1st week after surgery | 
| The position of IOL | Evaluation of the position of IOL through tilt, decentration and the process of capsule bending using CASIA2. | The 1st month after surgery | 
| The position of IOL | Evaluation of the position of IOL through tilt, decentration and the process of capsule bending using CASIA2. | The 3rd month after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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High Myopia, Various Types of IOLs, The position of IOL