Posterior chamber IOL gluing technique safer, easier than scleral suturing

Insertion of a foldable lens through a small clear corneal tunnel and externalized haptics minimized complications at 1 year postop.

Introduction

Thomas John

Secondary IOL implantation or surgical management of an IOL dislocation/subluxation has been described in adult and pediatric age groups. Surgical techniques include scleral-fixated posterior chamber IOL, placement of an anterior chamber IOL or iris fixation of an IOL. Additional procedures include lens guide suture for transport and fixation in secondary IOL implantation in aphakia, the use of tissue adhesive, or tucking the externalized haptics of an IOL into scleral needle-tunnel pockets.

The choice of surgical procedure should be based on surgeon familiarity of the technique combined with proven efficacy and safety of the procedure. While there is no single surgical technique that is universally superior to others, various techniques appear on the horizon for surgeons to consider and possibly add to their list of surgical armamentarium. In this column, Dr. Cyres K. Mehta describes a puncture tunnel technique for gluing a foldable posterior chamber IOL. It is important to observe and follow these patients long term to prove the viability of new surgical procedures.

– Thomas John, MD
OSN Surgical Maneuvers Editor

A new posterior chamber IOL fixation technique yielded positive refractive outcomes and a high safety profile for aphakic patients and those with intraoperative capsular complications, a study showed.

The puncture tunnel technique for gluing posterior chamber foldable lenses is a safe alternative to anterior chamber lens implantation and a simpler alternative to sclerally fixated sutured IOLs, Cyres K. Mehta, MD, said at the European Society of Cataract and Refractive Surgeons meeting in Barcelona.

Dr. Mehta presented 1-year study results and described how the technique minimizes complications.

“The IOL is well-maintained by the haptics and does not twist,” Dr. Mehta said in a subsequent e-mail interview with Ocular Surgery News. “Also, it does not touch the iris. Postoperative outcomes are good, as the chamber is well-maintained. Visual and refractive outcomes are within those expected for regular [posterior chamber] IOL in-the-bag implantation.”

OSN Complications Consult Editor Amar Agarwal, MS, FRCS, FRCOphth, pioneered the use of fibrin glue to fixate externalized haptics in 2007, Dr. Mehta said.

Technique and outcomes

The puncture tunnel technique involves creating a conjunctival peritomy and triangular half-thickness scleral flap. A three-piece lens is injected through a 2.5-mm clear corneal tunnel and over a repositor. The lens haptics are fed into a 26-gauge needle. A puncture is made in the tunnel. The haptics are looped and fed through the tunnel. Lastly, fibrin glue is applied to a dry surface and the flap is held down for 2 minutes to affix the lens, Dr. Mehta said.

Figures 1-4. After the posterior chamber IOL is introduced, a conjunctival peritomy and a triangular half thickness scleral flap is created (top row). Then the three-piece lens is injected over a repositor through a 2.5 mm clear corneal tunnel (bottom row). Images: Mehta CK

Figures 5 and 6. The haptic is positioned within the sclera and fed into the 26-gauge needle.

Figure 7. A puncture made in the tunnel.

Figure 8. The loop is crimped and fed in.

Figures 9 and 10. Fibrin glue is applied to a dry surface and the flap held down for 2 minutes.

The study included 30 patients ranging in age from 37 to 85 years; 26 patients were aphakic, with no posterior capsular support, and four patients had posterior capsule ruptures and insufficient capsular support for IOL implantation.

At postop day 1, seven patients had a streak of hyphema in the anterior chamber and a grade 1 flare with cells. The flare and cells disappeared by postop day 7, Dr. Mehta said.

At 1 year, no patients had pseudophakodonesis, and all lenses were centered in the pupillary space in the posterior chamber. The lens edge was not visible in the pupil in any cases, he said.

Enhanced safety and efficacy

The puncture tunnel technique results in less residual astigmatism than other gluing techniques, Dr. Mehta said.

“There is minimal astigmatism, as the lens is foldable and injected into the eye through a 2.5-mm clear corneal tunnel, unlike current glued IOL techniques that use a 6-mm optic single-piece PMMA lens with PMMA haptics, which have to be inserted through a large incision that must be sutured to maintain watertightness,” Dr. Mehta said.

The method is also simpler and safer than anterior chamber IOL fixation techniques, he said.

“Other suturing techniques are time-consuming and elaborate, and depend on the long-term integrity of sutures as thin as 10-0, which are known to degrade over time,” he said. “[Anterior chamber] lens implants rely on having to make a large 6-mm corneal incision and insert the lens. The iris may be snagged during insertion, and while rotating the IOL, we can cause bleeding due to iridodialysis or angle structure damage. Long-term endothelial cell loss is well known in [anterior chamber] lenses, as is the tendency to cause glaucoma, and uveitis and pigment dispersion from the lens rubbing on the iris.”

Additionally, the technique involves a minimal risk of hyphema from ciliary bleeding, Dr. Mehta said. – by Matt Hasson

• Cyres K. Mehta, MD, can be reached at International Eye Centre, Mistry Chambers, Ground Floor, Brahmakumaris Marg, Mumbai 400005, India; 91-22-652-61579; e-mail: cyresmehta@yahoo.com.