Secondary IOL implantation was traditionally performed for aphakia but is now most commonly done during IOL exchange surgery.
Preoperative Evaluation
Careful slit-lamp biomicroscopy with attention to:
- Corneal endothelium
- IOP
- Presence of vitreous in anterior chamber
- Angle and iris abnormalities
- Presence and adequacy of capsular support, macula and peripheral retina, and optic nerve
Posterior Chamber:
- Capsular bag: best location for IOL if bag is intact with adequate support
- Sulcus:
- Adequate capsular support: Does not require suture; this is the next best location after capsular bag. Capture IOL optic through intact anterior capsulotomy if present.
- Inadequate capsular support: Requires suture fixation to iris or sclera
- Iris suture: Modified McCannel suture, tie with Siepser knot
- Transscleral suture: Technically more difficult, longer procedure time, requires thorough anterior vitrectomy, risk of ciliary body hemorrhage and suture erosion.
- Iris fixated: Iris-claw lens easiest surgical technique and fewer complications; requires peripheral iridectomy; also may be fixated to posterior iris surface.
- Anterior chamber: Easier, faster and less traumatic than suture techniques; long-term results equivalent to sulcus with scleral suture fixation; requires peripheral iridectomy but may not require anterior vitrectomy; contraindicated if corneal endothelial damage, angle abnormalities, or glaucoma exists.
Surgical Technique
Posterior chamber:
- Iris fixation: Capture IOL optic through pupil, place two McCannel-style sutures with 9-0 polypropylene on a long curved needle, retrieving needle can be facilitated by docking in cannula, Siepser knot minimizes traction on iris and haptics.
- Scleral fixation: Numerous techniques with or without scleral flaps, secure with suture (9-0 polypropylene or 8-0 gortex on a long curved or straight needle) or glue. Safest techniques utilize 27-gauge hollow needle for precise positioning and docking/retrieving the suture needle.
Iris-claw: Careful attention to centration during enclavation, must create peripheral iridectomy to prevent pupillary-block angle-closure glaucoma. Anterior chamber: constrict pupil, Sheet’s glide to facilitate insertion, push/pull-elevate-release haptic technique for proper footplate positioning in angle, must create peripheral iridectomy to prevent pupillary-block angle-closure glaucoma.
Reference:
Friedman NJ, Khater TT, Kohnen T, Koch DD. "Secondary Intraocular Lens Implantation." In: Tasman W, Jaeger EA. (eds): Duane's Clinical Ophthalmology. Volume 6. Philadelphia. Lippincott, Williams, & Wilkins Publishers. 2011.