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Trial record 10 of 420 for:    cataract AND intraocular lens

Comparison of In-the-bag Stability Between Single-piece and Three-piece Intraocular Lens

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ClinicalTrials.gov Identifier: NCT02609997
Recruitment Status : Completed
First Posted : November 20, 2015
Last Update Posted : November 20, 2015
Sponsor:
Information provided by (Responsible Party):
Haotian Lin, Sun Yat-sen University

Brief Summary:

Rapid advances of cataract surgery techniques and intraocular lens (IOL) technology have enabled the transition of cataract surgery from blindness relief to refractive correction. An ideal IOL is the critical component to achieve the refractive target of cataract surgery. Biocompatibility, rate of posterior capsule opacification (PCO) and visual quality have all been suggested as the critical factors of an ideal IOL and widely investigated. Recently, stability of IOL position has also been suggested as one of those critical factors due to its close correlation with postoperative visual function. Data suggests that IOL forward movement of 0.29 mm along the visual axis is associated with -0.4D myopic shift. Wang and colleagues recently reported that 0.5mm decentration of an aspheric IOL could eliminate its aberration-correcting effect. Poor stability could even lead to IOL exchange, an additional surgery that put both surgeons and patients in pain.

As the supporting element of an IOL, the haptics are crucial to keep the IOL in place. Various haptic designs are being compared in terms of position stability of IOLs. Haptic designs of single-piece versus 3-piece are often compared because they are currently the most commonly used types. Single-piece IOLs have soft and broader haptics which are made of the same material as the optic, usually hydrophobic or hydrophilic acrylic, whereas 3-piece IOLs have rigid haptics which are made of poly methyl methacrylate (PMMA). Clinical studies comparing these haptic designs have yielded controversial results regarding their position stability in the capsular bag, which is the most recommended site for IOL fixation in an uneventful cataract surgery.


Condition or disease Intervention/treatment Phase
Cataract Procedure: Phacomulsification lens removal cataract surgery with single-piece Intraocular lens(IOL) implantation Procedure: Phacomulsification lens removal cataract surgery with three-piece Intraocular lens(IOL) implantation Drug: Subconjunctival dexamethasone Device: Viscoelastic materials Drug: proparacaine Not Applicable

Detailed Description:

Rapid advances of cataract surgery techniques and intraocular lens (IOL) technology have enabled the transition of cataract surgery from blindness relief to refractive correction. An ideal IOL is the critical component to achieve the refractive target of cataract surgery. Biocompatibility, rate of posterior capsule opacification (PCO) and visual quality have all been suggested as the critical factors of an ideal IOL and widely investigated. Recently, stability of IOL position has also been suggested as one of those critical factors due to its close correlation with postoperative visual function. Data suggests that IOL forward movement of 0.29 mm along the visual axis is associated with -0.4D myopic shift. Wang and colleagues recently reported that 0.5mm decentration of an aspheric IOL could eliminate its aberration-correcting effect. Poor stability could even lead to IOL exchange, an additional surgery that put both surgeons and patients in pain.

As the supporting element of an IOL, the haptics are crucial to keep the IOL in place. Various haptic designs are being compared in terms of position stability of IOLs. Haptic designs of single-piece versus 3-piece are often compared because they are currently the most commonly used types. Single-piece IOLs have soft and broader haptics which are made of the same material as the optic, usually hydrophobic or hydrophilic acrylic, whereas 3-piece IOLs have rigid haptics which are made of poly methyl methacrylate (PMMA). Clinical studies comparing these haptic designs have yielded controversial results regarding their position stability in the capsular bag, which is the most recommended site for IOL fixation in an uneventful cataract surgery.

Most previous studies measure the IOL position based on Purkinje reflections. The measurement is time-consuming and patients are reluctant to cooperate during image acquisition. Purkinje measurement does not detect anterior chamber depth (ACD) and as such cannot reveal the IOL position along the axis. Clinical Scheimpflug systems based on rotating Scheimpflug imaging, on the other hand, is able to acquire sufficient 3-dimensioinal data points within a reasonably short period, usually seconds. It was shown that these systems are one of the best methods to estimate IOL position. To better compare the intracapsular stability between single-piece and 3-piece IOLs, the investigators measured IOL positions with rotating Scheimpflug imaging systems and tested the visual quality of patients implanted with these IOLs.


Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 65 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single (Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Comparison of In-the-bag Stability Between Single-piece and Three-piece Intraocular Lens Via Scheimpflug Imaging System
Study Start Date : September 2012
Actual Primary Completion Date : December 2012
Actual Study Completion Date : December 2012

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Cataract

Arm Intervention/treatment
Experimental: Single-piece IOL Group
Age-related cataract patients receive in-the-bag implantation of a single-piece IOL
Procedure: Phacomulsification lens removal cataract surgery with single-piece Intraocular lens(IOL) implantation
The phacoemulsification lens removal cataract surgery is performed with single-piece IOL.During Phacoemulsification.

Drug: Subconjunctival dexamethasone
All patients received subconjunctival dexamethasone (2 mg) during surgery. Topical anesthesia, consisting of a single drop of 0.5% proparacaine (Alcaine, Alcon Laboratories), was administered three times at intervals of 5 minutes prior to surgery

Device: Viscoelastic materials
viscoelastic materials are used to protect corneal endothelial cells

Drug: proparacaine
0.5% proparacaine (Alcaine, Alcon Laboratories)

Experimental: Three-piece IOL Group
Age-related cataract patients receive in-the-bag implantation of a three-piece IOL
Procedure: Phacomulsification lens removal cataract surgery with three-piece Intraocular lens(IOL) implantation
The phacoemulsification lens removal cataract surgery is performed with three-piece IOL.During Phacoemulsification.

Drug: Subconjunctival dexamethasone
All patients received subconjunctival dexamethasone (2 mg) during surgery. Topical anesthesia, consisting of a single drop of 0.5% proparacaine (Alcaine, Alcon Laboratories), was administered three times at intervals of 5 minutes prior to surgery

Device: Viscoelastic materials
viscoelastic materials are used to protect corneal endothelial cells

Drug: proparacaine
0.5% proparacaine (Alcaine, Alcon Laboratories)




Primary Outcome Measures :
  1. The grade of in-the-bag stability between single-piece intraocular lenses (IOLs) and three-piece intraocular lenses(IOLs) [ Time Frame: 3 months after the surgery ]

Secondary Outcome Measures :
  1. The visual acuity between single-piece intraocular lenses (IOLs) and three-piece intraocular lenses(IOLs) [ Time Frame: 3 months after the surgery ]


Information from the National Library of Medicine

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Ages Eligible for Study:   60 Years to 85 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • diagnosis of bilateral age-related cataract and age between 60 to 85 years

Exclusion Criteria:

  • vision-impairing diseases other than cataract, severe refractive error (Preoperative spherical equivalent of either eye >-6.00D or +5.00D)
  • history of ocular trauma, past refractive surgery or other ophthalmic surgery, capsular or zonular disorders that might affect the post-operative centration of IOLs
  • surgical complications including severe hyphema, iris injury, repeated IOL implantation
  • unable to achieve in-the-bag implantation of IOL, corneal sutures during surgery

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT02609997


Locations
China, Guangdong
Zhognshan Ophthalmic Center, Sun Yat-sen University
Guangzhou, Guangdong, China, 510060
Sponsors and Collaborators
Sun Yat-sen University
Investigators
Principal Investigator: Haotian Lin, M.D., Ph.D Zhongshan Ophthalmic Center, Sun Yat-sen University
Study Chair: Yizhi Liu, M.D., Ph.D Zhongshan Ophthalmic Center, Sun Yat-sen University
Study Director: Weirong Chen, M.D. Zhongshan Ophthalmic Center, Sun Yat-sen University

Additional Information:
Publications:
Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: Haotian Lin, Principal Investigator, Home for Cataract Children, Zhongshan Ophthalmic Center, Sun Yat-sen University
ClinicalTrials.gov Identifier: NCT02609997     History of Changes
Other Study ID Numbers: CCPMOH2010-China9
First Posted: November 20, 2015    Key Record Dates
Last Update Posted: November 20, 2015
Last Verified: November 2015

Keywords provided by Haotian Lin, Sun Yat-sen University:
Intraocular lens

Additional relevant MeSH terms:
Cataract
Lens Diseases
Eye Diseases
Dexamethasone acetate
Dexamethasone
Proxymetacaine
Propoxycaine
BB 1101
Anti-Inflammatory Agents
Antiemetics
Autonomic Agents
Peripheral Nervous System Agents
Physiological Effects of Drugs
Gastrointestinal Agents
Glucocorticoids
Hormones
Hormones, Hormone Substitutes, and Hormone Antagonists
Antineoplastic Agents, Hormonal
Antineoplastic Agents
Protease Inhibitors
Enzyme Inhibitors
Molecular Mechanisms of Pharmacological Action
Anesthetics, Local
Anesthetics
Central Nervous System Depressants
Sensory System Agents