Abstract
Purpose :
The management of secondary intraocular lens (IOL) placement in the absence of sufficient capsular or zonular support continues to evolve. Anterior chamber IOLs (ACIOL) have been the mainstay of management for many years, but can cause endothelial cell loss, corneal decompensation and glaucoma. New alternative methods including iris and scleral sutured techniques are more technically complex and carry risks such as suture erosion, iris chafing, and less predictable refractive outcomes. Herein we describe a novel device to suturelessly create a capsular support assembly within the posterior chamber to support either a primary or secondary intraocular lens.
Methods :
The implant was designed to allow insertion through a corneal incision of < 4mm and to externalize fixation anchors through 25 gauge sclerotomies. Computer-aided design (CAD) software was implemented to produce multiple device iterations. A Form2 stereo lithography (SLA) printer was used for rapid device and mold prototyping in conjunction with medical grade silicone. Finite element analysis (FEA) was conducted to simulate device manipulation such as stress/strain, and fatigue simulation. In conjunction with FEA, prototypes were implanted into ex vivo porcine eyes and the ability to fixate the device was evaluated both for ease of fixation and security of attachment. Results from FEA were cross referenced with ex vivo porcine implantation experiments to isolate design flaws which were then incorporated into subsequent design iterations.
Results :
The implant is an asymmetric annular ring with an internal groove for IOL haptic capture with 3 equally spaced externalizable scleral anchoring haptics. Numerous prototypes were evaluated on the basis of ease of scleral fixation, stereo-stability and centration with and without an IOLs. Current iterations of the device have demonstrated quick and secure anchoring to the sclera via 25-gauge sclerotomies. Additionally, this design was able to maintain IOL centration and effective lens position in various globe orientations.
Conclusions :
A novel artificial capsule device for primary or secondary IOLs fixation was designed and rapidly prototyped using a 3D printer. Optimized using FEA, prototypes were successfully implanted in an ex vivo porcine model and demonstrated secure scleral fixation and IOL stability. Future work will be directed to further evaluating this design in in vivo animal models.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.