Intraocular Lens-shell Technique in Phacoemulsification

Sun Yat-sen University

Status: Completed

Conditions: Cataract; Pseudoaphakia

Treatments: Procedure: Conventional procedure; Procedure: IOL-shell technique

Study type: Interventional

Funder types: Other

Identifiers

NCT02138123

CCPMOH2010-China5

Details and patient eligibility

About

In this study, the investigators introduce a surgical procedure called "IOL-shell technique" in the purpose of reduce complications of surgeries for dense cataract, and report a prospective randomized controlled study aiming at assessing efficacy and safety of the IOL-shell technique, which showed that the new procedure offered a safer way for hard cataract surgery over the conventional phacoemulsification procedure without compromise in efficacy.

Full description

A Prospective, randomized controlled study of 80 eyes with dense nucleus were enrolled. Patients were assigned to two groups: Group I: IOL was traditionally implanted after all nuclear fragments were completely removed, while in Group II, IOL was innovatively implanted in the bag before last residual nuclear fragment was removed. This novel adjusted surgical procedure, featured by using IOL as a protective barrier (named "IOL-shell technique"), not just as a refractive alternative, was conceptual different from the traditional step-by-step procedure. Clinical examinations including uncorrected visual acuity, central corneal thickness (CCT), temporal clear corneal thickness and the corneal endothelial cell density were carried out.

Enrollment: 80 patients

Sex: All

Ages: 50 to 90 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Aged 50 years or above
• Dense cataract cases were defined as eyes in which the nuclear color was graded IV or V according to the Lens Opacities Classification System III (LOCS III). Special attention was paid in selecting cases without apparent posterior cortical layer.
• No central corneal opacification
• Pupil diameter >= 7 mm after full pharmacological dilation in preoperative assessment
• A preoperative central endothelial cell count of >= 1500 cells/mm2.

Exclusion criteria

• Participants with previous intraocular surgery
• Abnormal lens zonules
• Glaucoma
• High myopia (>-6.0 Diopters)
• Pseudoexfoliation
• Uveitis
• Diabetes mellitus
• Those who were not able to come for follow-up visits.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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80 participants in 2 patient groups

IOL-shell technique

Experimental group

Description:

In this group, before the emulsification of the last nuclear fragment, cohesive viscoelastic material was injected below the nuclear fragment and a foldable IOL was implanted into the well inflated capsular bag posterior to the nuclear fragment. The remaining last piece of nuclear fragment was then emulsified and removed within the capsular bag.

Treatment:

Procedure: IOL-shell technique

Conventional procedure

Active Comparator group

Description:

In this group, a Sensar IOL (AMO Laboratories) was implanted in the capsular bag with the injector system after the lens material was completely removed. The nuclear fragmentation was performed using the Phaco-chop technique, which was then followed by ultrasound emulsification of the nuclear fragments piece by piece. Due to lack of cortical shell within the capsular bag, special care was taken to carry out the emulsification of the last nuclear fragment at a relatively more anterior anatomical position between the iris plan and the anterior chamber.

Treatment:

Procedure: Conventional procedure