Sutureless intrascleral posterior chamber IOL fixation offers long-term stability, centration

As innovations in IOL design and optics continue to improve visual and refractive outcomes in cataract surgery, ongoing advances in surgical technique enable surgeons to further maximize outcomes and handle challenging cases.

Posterior chamber IOLs are sutured in back of the iris or the capsular bag. However, suturing may not be feasible in cases with insufficient capsule, trauma, aniridia, pseudoexfoliation, lens subluxation or loss of zonular integrity.

In recent years, evolving techniques have enabled surgeons to perform intrascleral haptic fixation, with or without sutures. Experts say the technique and its variants improve the long-term stability of posterior chamber IOLs.

Sutureless intrascleral haptic fixation of a three-piece posterior chamber IOL in the ciliary sulcus in eyes with no capsule support was first reported by Scharioth and colleagues in the Journal of Cataract and Refractive Surgery in 2007.

The original sutureless technique involved tucking the IOL haptics into scleral tunnels parallel to the limbus, with no suturing or gluing.

Also in 2007, Amar Agarwal, MS, FRCS, FRCOphth, OSN Asia-Pacific Edition Editorial Board Member, and Soosan Jacob, MS, FRCS, introduced a key innovation to sutureless intrascleral posterior chamber IOL implantation: the use of fibrin glue to secure the scleral flaps under which the lens haptics are tucked.

There is a high degree of stability afforded by using the glued IOL technique as opposed to sutures, according to Amar Agarwal, MS, FRCS, FRCOphth. Image: Agarwal A

Drs. Agarwal and Jacob also pioneered the handshake technique, in which the surgeon transfers the lens haptics from one hand to the other to safely manipulate them in a closed-globe surgical setting.

Dr. Agarwal said there is a high degree of stability afforded by gluing as opposed to suturing.

“One main reason for good results in the glued IOL is that there is no pseudophakodonesis in such cases, unlike a sutured IOL, which moves like a hammock,” Dr. Agarwal said. “On high-speed videography … one can see that the glued [posterior chamber] IOL does not move.”

Ike K. Ahmed, MD, FRCSC, OSN Glaucoma Board Member, said the gluing technique offers advantages in terms of facility and stability.

“This offers a sutureless technique of IOL fixation that is certainly quite manageable for the anterior segment surgeon,” Dr. Ahmed said. “I think that lenses are stable, and I think they probably have the best chance of stability in terms of long-term centration and fixation.”

John A. Hovanesian, MD, FACS, OSN Cornea/External Disease Board Member, echoed Dr. Ahmed’s observation.

“For the surgeon, it offers a simple technique for lens fixation in an aphakic eye that doesn’t require the clumsiness and challenging steps involved with sutured fixation,” Dr. Hovanesian said. “For the patient, it offers what appears to be a very stable lens fixation without shaking or pseudophakodonesis as seen with sutured techniques. Although we have limited years of follow-up, it is likely to continue to secure the lens well for many years to come.”

The gluing technique is feasible for three-piece posterior IOLs, Kenneth J. Rosenthal, MD, FACS, OSN Cataract Surgery Board Member, said.

“Essentially, the glued IOL technique is a good technique for basically any posterior chamber IOL fixation in the absence of capsular support, excluding lenses that are already within a capsular bag,” Dr. Rosenthal said.

Indications and lens types

Sutureless fixation was initially indicated for eyes with absent or insufficient capsular support. Indications have been expanded to encompass aphakia without capsular support, progressive subluxation, pseudoexfoliation and coloboma of the lens.

“There are two main indications,” Dr. Ahmed said. “One is aphakia — people who are aphakic, and there are still some of those around who need a secondary lens, whether they’ve had previous cataract surgery remotely or whether they’ve had cataract surgery recently and had a complication and were left aphakic. Second would be dislocated lenses of different positions and different styles. We sometimes exchange them for another lens or try to reposition the existing lens. Either way, we can potentially use this technique.”

Ike K. Ahmed

Any three-piece IOL is suitable for intrascleral fixation, Dr. Ahmed said. He said he prefers foldable three-piece acrylic or silicone lenses and advises against using one-piece foldable acrylic lenses or hydrophobic lenses.

Rigid one-piece PMMA lenses are not amenable to sutureless fixation, Dr. Ahmed said.

“I have tried this with a rigid PMMA lens, and I don’t advise it,” he said. “I think it’s difficult to implant a PMMA lens, and it’s certainly a risk that I’ve seen haptics break with the one-piece PMMA lenses. A three-piece PMMA lens might be amenable, but a one-piece PMMA would be a no-go, so I generally avoid it in that situation. I would take the PMMA lens out of the eye and then exchange it for a three-piece acrylic lens and fixate it intrasclerally.”

The glued IOL technique cannot be done with a single-piece foldable IOL because the haptics are not firm to tuck and glue, Dr. Agarwal said.

Dr. Hovanesian described sutureless intrascleral IOL fixation as safer and easier than suturing a lens into the scleral flap.

“There are several advantages to this technique,” Dr. Hovanesian said. “First, it doesn’t involve sutures, so the risk of having sutures that come loose or are inadvertently cut goes away. Another advantage there is that scleral fixation with sutures is a somewhat clumsy procedure where there are long strands of thread that are in the operative field. It’s a challenging and frustrating procedure for surgeons to perform in many cases, whereas this technique is quite elegant.”

Dr. Agarwal noted that the technique has been performed in children with good results.

Basic technique

The basic glued fixation technique, as described by Dr. Agarwal in his Complications Consult columns in Ocular Surgery News, involves creating two 2.5 mm × 2.5 mm lamellar scleral flaps placed 180° apart. Sclerotomies are made under the flaps, 1 mm to 1.5 mm from the limbus. A pars plana vitrectomy is performed with a 23-gauge vitrector introduced through the sclerotomy or an anterior vitrector directed through a corneal paracentesis.

A corneoscleral incision is created to introduce the IOL and the leading haptic of the IOL. After the IOL is injected into the eye, the leading haptic and trailing haptic are brought to the exterior through the sclerotomies using 23-gauge MicroSurgical Technology (MST) forceps. The haptics are fixed into scleral pockets created at the edge of the flap with a 26-gauge needle. The scleral flaps are held down with fibrin glue.

“I usually like to go superior to inferior because the white-to-white is a little bit shorter and because it provides better fixation because of gravity effects,” Dr. Rosenthal said. “Once the scleral flaps are made, we take a 26-gauge hypodermic needle, enter through the ciliary sulcus ab externo, create an opening and using an end-grasping vitreoretinal forceps, we’ll go in and grasp the very distal end of the haptic. It’s important to grab the very distal end because if you grab it in the middle as you pull it out, you’re going to crimp the haptic.”

Dr. Agarwal described the benefits of gluing the haptics, conjunctiva and corneal incision.

“The glue seals the haptics to the sclera,” he said. “The glue further helps in preventing any exposure of the vitreous to the outside as all are sealed with the glue. This prevents any chance of endophthalmitis. A third advantage of the glue is that the glue seals the sclerotomy created with the scleral flap so that there is no trabeculectomy sort of opening left. Finally, the same glue is used to seal the conjunctiva and the clear corneal incisions.”

Dr. Ahmed said it is important to use the proper instrumentation when performing glued IOL fixation.

“Micro-instruments like micro-forceps really make these techniques much more manageable,” Dr. Ahmed said.

John A. Hovanesian

Despite the name of the technique, glue alone does not maintain long-term IOL stability, Dr. Hovanesian said.

“To describe this procedure as a glued IOL doesn’t fully characterize the stability of the lens fixation,” he said. “It implies that the glue and nothing else is holding the lens in place. [Fibrin glue] only retains adhesion for a week or so. What’s really securing the lens in this procedure is a scleral pocket that the tip of the IOL haptic is tucked into. The glue holds down the partial thickness scleral flap that covers the entrance to this tunnel externally.”

As described by Drs. Agarwal and Jacob in OSN, the handshake technique involves the surgeon, using two MST forceps, holding the haptic with one set of forceps and directing another set of forceps through the opposite sclerectomy or side port. Holding the haptic at its tip before externalizing it prevents it from snagging on the sclerotomy.

“One hand would grasp the haptic itself from inside. Hold it steady so that the forceps coming from the ciliary sulcus incision would then have stability to grasp the haptic and pull it out,” Dr. Rosenthal said. “That’s done on two sides. Once the lens is in good position and you can alter it a little bit, then you make a scleral tunnel using, again, the 26-gauge needle so it will micro-tunnel along the following edge of scleral flap. In other words, at the edge of the scleral flap, we make a tunnel and into that tunnel the haptic is tucked so that, now, the entire haptic is either under the scleral flap or in that tunnel.”

Variations

Dr. Rosenthal said he uses a slight variation on Dr. Agarwal’s glued fixation technique. He secures the haptic with one suture under the scleral flap to maximize fixation.

“I have generally been applying a suture because it’s not very time consuming and it does give us a little bit of security. I’m also using this technique now in some high-risk cases or younger patients, where long-term stability needs to really be stabilized,” Dr. Rosenthal said.

Dr. Rosenthal said he applies Tisseel tissue glue (Baxter) to the scleral flap bed over the haptic and seals it.

Postop glued IOL. Note the scleral flaps and the blue haptics tucked and glued in the sclera. Images: Agarwal A

Handshake technique. F1, forceps 1; F2, forceps 2.

“In doing this, as we’re placing the haptics, we can pull the haptic out or push it back into the eye to create perfect centration of the IOL,” Dr. Rosenthal said. “We’ve even used this technique now in a few cases with multifocal lenses with excellent centration results.”

In addition, Dr. Rosenthal said that he uses an endoscope placed under the edge of the iris to see behind the iris and ensure that he is operating in the ciliary sulcus.

“There’s a lot of variation from one patient to another in the location of the ciliary sulcus,” Dr. Rosenthal said. “What you don’t want to do is go through the ciliary body for three main reasons. One, you’re going to have a poorly placed lens. No. 2, you’re going to have bleeding. Three, you can disinsert the ciliary body and create a cyclodialysis cleft.”

The endoscope lets the surgeon follow the trajectory of the needle as it enters the ciliary sulcus when doing a sutured IOL, Dr. Rosenthal said.

“Actually, if you put the endoscope in before you place the needle as you’re starting to push the needle in, you can actually see a dimpling or an indentation of the needle track as it starts to come into the ciliary sulcus,” he said. “It’s actually quite a neat technique.”

Dr. Ahmed said that he sutures posterior chamber IOLs to the posterior iris surface as an alternative to intrascleral fixation in cases in which the technique is suitable.

“I can’t say that one is superior to the other,” Dr. Ahmed said. “They both have theoretical advantages, depending on how you look at it. There are pros and cons to either one of these approaches.”

Potential pitfalls

Sutureless intrascleral haptic fixation has potential drawbacks, such as poor preoperative planning and insufficient scleral tissue, Dr. Ahmed said.

“Some of the pitfalls with these techniques are inadequate planning, particularly when it comes to the incisions and where you make the incisions and where you make your scleral grooves. So, it’s always important to plan where the haptic will be fixated and make your incisions accordingly, No. 1,” Dr. Ahmed said. “No. 2, the sclera needs to be of reasonable thickness and reasonable health.”

Surgeons should also be wary of blebs and be sure to perform a vitrectomy as part of the intrascleral fixation procedure, Dr. Ahmed said.

“If there’s a pre-existing trabeculectomy bleb, I would avoid it because that could potentially cause bleb failure by manipulating the conjunctiva,” he said. “Vitrectomy is important. If the vitrectomy has not been adequately performed, there’s a high risk of vitreous incarceration with the technique.”

Dr. Rosenthal said that a partial-thickness scleral patch graft can be placed over areas of the sclera that are too thin where the haptic emerges onto the surface.

Measurement of the white-to-white diameter of the cornea is also critical. If the white-to-white measurement is 12 mm and a foldable IOL is 13 mm, there would not be enough externalized haptic to tuck and glue. A vertical glued IOL is a suitable substitute, because the vertical white-to-white distance is shorter than the horizontal white-to-white distance. Scleral flaps would be created at the 12 o’clock and 6 o’clock positions in such a case, Dr. Agarwal said.

In addition, glued posterior chamber IOLs may solve the problem of IOL subluxation in cases of pseudoexfoliation, Dr. Agarwal said.

“Today’s literature shows lots of patients who were operated years back for cataract and had pseudoexfoliation today have those IOLs subluxated, even some with endocapsular rings,” he said. “With glued IOLs this will not happen. Pseudoexfoliation is a progressive condition. With time the lenses will subluxate more. What we do is remove the cataract totally and put in the glued IOL. So, the basic problem of pseudoexfoliation is never present, and for life the IOL will remain sturdy and fixed.”

A look at the literature

In their pioneering 2007 study, Scharioth and colleagues reported that no complications occurred during 3-month follow-up of the first five cases of sutureless fixation.

In a subsequent 2010 study, also published in the Journal of Cataract and Refractive Surgery, Scharioth and colleagues reported outcomes in 63 patients followed for a mean 6.8 months. Results showed that two posterior chamber IOLs were decentered and 61 IOLs were stable and well-centered. No cases of recurrent dislocation, endophthalmitis, retinal detachment or glaucoma were identified.

Results also showed a statistically significant improvement in corrected distance visual acuity (P = .005).

In a study published in the Journal of Cataract and Refractive Surgery by McAllister and Hirst, sutured scleral IOL fixation yielded positive visual outcomes but resulted in various complications.

The study included 82 eyes of 72 patients who underwent surgery between 1993 and 2008. Mean patient age at the time of surgery was 62 years. Mean follow-up was 83.3 months.

Results showed a statistically significant mean improvement in Snellen corrected distance visual acuity of 1.6 lines (P = .001). Corrected distance visual acuity was improved or unchanged in 59 eyes and diminished in 23 eyes.

The most common postoperative complication was ocular hypertension, identified in 25 eyes; 11 of those 25 eyes had a history of glaucoma. In addition, suture breakage occurred in five eyes. In total, 44 eyes had at least one complication; 36.4% of complications were reported in the first week after surgery, and 63.6% of complications were reported after 1 week.

Subsequent surgery was required in 13 eyes (15.8%), the authors reported.

The authors identified suture rupture as a potential risk for patients younger than 40 years. – by Matt Hasson

When is it advisable to suture IOL haptics, and when should haptics be tucked or glued into a scleral tunnel?

Lindstrom's Perspective
Despite inadequate capsular support, several options available to fixate IOLs

References:

• Agarwal A, Kumar DA, Jacob S, Baid C, Agarwal A, Srinivasan S. Fibrin glue-assisted sutureless posterior chamber intraocular lens implantation in eyes with deficient posterior capsules. J Cataract Refract Surg. 2008;34(9):1433-1438.
• Jacob S, Kumar DA, Agarwal A. Glued IOL procedure evolves with use of handshake technique. Ocular Surgery News. Feb. 10, 2011;29(3):32.
• Kumar DA, Agarwal A, Jacob S, et al. Sutureless scleral-fixated posterior chamber intraocular lens. J Cataract Refract Surg. 2011;37(11):2089-2090.
• Kumar DA, Agarwal A, Prakash G, Jacob S, Saravanan Y, Agarwal A. Glued posterior chamber IOL in eyes with deficient capsular support: a retrospective analysis of 1-year postoperative outcomes. Eye (Lond). 2010;24(7):1143-1148.
• McAllister AS, Hirst LW. Visual outcomes and complications of scleral-fixated posterior chamber intraocular lenses. J Cataract Refract Surg. 2011;37(7):1263-1269.
• Scharioth GB, Pavlidis MM. Sutureless intrascleral posterior chamber intraocular lens fixation. J Cataract Refract Surg. 2007;33(1):1851-1854.
• Scharioth GB, Prasad S, Georgalas I, Tataru C, Pavlidis MM. Intermediate results of sutureless intrascleral posterior chamber intraocular lens fixation. J Cataract Refract Surg. 2010;36(2):254-259.

• Amar Agarwal, MS, FRCS, FRCOphth, can be reached at Dr. Agarwal’s Eye Hospital, 19 Cathedral Road, Chennai 600 086, India; fax: 91-44-28115871; email: dragarwal@vsnl.com.
• Ike K. Ahmed, MD, FRCSC, can be reached at Credit Valley EyeCare, 3200 Erin Mills Parkway, Unit 1, Mississauga, Ontario L5L 1W8, Canada; 905-820-6789; fax: 905-820-0111; email: ike.ahmed@utoronto.ca.
• John A. Hovanesian, MD, FACS, can be reached at Harvard Eye Associates, 24401 Calle De La Louisa, Suite 300, Laguna Hills, CA 92653; 949-951-2020; fax: 949-380-7856; email: drhovanesian@harvardeye.com.
• Kenneth J. Rosenthal, MD, FACS, can be reached at Waterview Building, Suite 102, 310 E. Shore Road, Great Neck, NY 11023; 516-466-8989; fax: 516-466-8962; email: kenrosenthal@eyesurgery.com.
• Disclosures: Dr. Agarwal is a consultant for Abbott Medical Optics, Bausch + Lomb and STAAR Surgical. Dr. Ahmed has no relevant financial disclosures. Dr. Hovanesian is a consultant for Abbott Medical Optics and Bausch + Lomb. Dr. Rosenthal is a consultant for Abbott Medical Optics, Alcon and Bausch + Lomb.