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

• Status: Completed
• Trial end date: 2012-12-01
• Target enrollment: 0
• Participant gender: All

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.

• Phase: N/A
• Accepts Healthy Volunteers?: No

Details

• Lead Sponsor: Sun Yat-sen University
• Treatments: BB 1101; Dexamethasone; Dexamethasone 21-phosphate; Dexamethasone acetate; Propoxycaine; Proxymetacaine

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