Glued intrascleral posterior chamber IOL fixation technique continues to evolve
Suturing of posterior chamber IOLs in back of the iris or the capsular bag is standard practice, but it may not be appropriate in cases with insufficient capsule, lens subluxation or loss of zonular integrity.
In the last decade, surgeons began to perform posterior chamber IOL implantation using an intrascleral haptic fixation technique, with or without sutures. Experts say the technique and its variants enhance the long-term stability of posterior chamber IOLs.
Sutureless intrascleral haptic fixation of a three-piece posterior chamber IOL in eyes with no capsular support was reported by Scharioth and colleagues 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 APAO Edition Board Member, and colleagues introduced a glued intrascleral haptic fixation technique. Agarwal later devised a series of variants such as the handshake technique and the trocar anterior chamber maintainer.
Soosan Jacob, MS, FRCS, DNB, OSN APAO Edition Board Member, devised the glued capsular hook. Priya Narang, MS, devised the no-assistant technique to make glued IOL surgery easier.
“Why do glued IOLs work so well? One, it is definitely easier and faster than a sutured lens technique,” Agarwal said. “But the bigger advantage is that the lens is very stable. It does not move. Also, there is generally no tilting of the lens, which can happen in a sutured lens.”
Narang said that glued intrascleral posterior chamber IOL fixation significantly reduces phacodonesis and pseudophakodonesis. This has been recorded on high frames per second on the iPhone and also on high-speed cameras.
“If you have an IOL that is moving in the eye with the eye movement, like you have in an iris fixation, or you have a sutured IOL or you have an anterior chamber IOL, there’s an element of pseudophakodonesis,” Narang said.
Eric D. Donnenfeld, MD, OSN Cornea/External Disease Board Member, said there are various advantages of the glued IOL technique.
“What I have liked about the glued IOL technique is that it allows for very good fixation and centration, and very rarely do you have lens tilt. ... I found both of those issues to be problems with scleral-fixated lenses using sutures,” Donnenfeld said. “The other advantage is that you don’t have to worry about the suture degrading over time. And, most importantly, I believe, from a surgeon’s perspective, the amount of dexterity required for this technique is really on par or less than the amount of dexterity required for the other procedures. In the right hands, I believe it’s actually an easier technique than the other techniques we’re using currently. I don’t use this technique exclusively, but I use it in a majority of my cases now.”
Glued intrascleral fixation
The basic glued fixation technique, as described by Agarwal and Jacob, involves creating two 2.5 mm by 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. The incision should be perpendicular to the flaps and not in a plane parallel to the flaps; otherwise, it is difficult to perform the handshake technique. This means if the flaps are vertical at the 12 and 6 o’clock position, the incision should be temporal. 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/Epsilon glued IOL forceps. The haptics are fixed into scleral pockets created at the edge of the flap with a 26-gauge needle, and the scleral flaps are sealed with fibrin glue. The surgeon applies Tisseel (Baxter) to the scleral flap bed over the haptic to seal it.
“This glue is made of normal blood. In other words, it is a tissue glue,” Agarwal said, adding that because it is made of normal blood, it is “absolutely safe.”
Fixation, however, hinges on the scleral flaps, not the glue, Francis W. Price Jr., MD, OSN Cornea/External Disease Board Member, said.
“The whole glued thing is a bit of a misnomer,” Price said. “The glue isn’t really an integral part of the surgery other than it makes it easier to put the flap down and makes it easier to put the conjunctiva back in place. The glue is only there for 4 or 5 days, just to seal, which is not long enough to really provide any fixation for anything. It just helps with the closure.”
Price said that the haptics are glued in the sclera because polypropylene sutures degrade.
“When the Prolene or polypropylene goes through the ciliary body, something in the ciliary body causes the material to actually begin to fracture and break,” Price said.
The handshake technique involves the surgeon 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.
“In other words, you’re shaking your hand from one hand to the other. The two forceps are actually your hands. You’re externalizing the haptics. So, the key point is externalization of the haptics,” Agarwal said.
Agarwal noted that intrascleral fixation must be performed with a three-piece IOL.
“It cannot be a single-piece foldable lens because, for a single-piece foldable, you need something firm to tuck into the intrascleral pocket. If it is not firm, it will not go into the pocket smoothly. A three-piece lens goes into the tunnel very clearly,” Agarwal said.
A 14-mm three-piece IOL would work better than a 13-mm implant in myopic or large eyes, Agarwal said.
“If the eye is large, what will happen here is the haptic is externalized less because the eye is too large. If we have 14-mm IOLs, then we will always have enough haptic to externalize and tuck into the Scharioth pocket,” Agarwal said.
Price said it can be difficult to choose a suitable lens for the handshake technique.
“You want a material that is going to last, and you want one that’s not going to break easily when you’re trying to manipulate the haptics,” Price said.
Price said that he and his group have started using the Aaren IOL (Carl Zeiss Meditec), which he described as sturdy and flexible.
“The only problem is the haptic diameter is 12.5 mm, so it can have a tendency to pull out in larger eyes,” Price said. “Also, the material is slick. So, what we’ve done for over a year now, when we put those in, we take a little hand-held cautery and make a little bulbous end on the end of the haptic so that once you thread it into the sclera, as it heals, it stays in place and doesn’t have a tendency to work out.”
Jacob described the handshake technique as simple and easy to learn.
“The handshake technique is really one of the most crucial steps in glued IOL surgery. Also, it’s something that’s very simple,” Jacob said. “There’s nothing to it because it’s just holding the two microforceps and passing the haptics from one hand to the other.”
One advantage of the handshake technique is the ability to do closed IOL fixations with 1.5-mm to 2-mm incisions in complex cases that would require larger incisions using other techniques, according to Donnenfeld. Furthermore, the technique creates a more stable anterior chamber.
“Disadvantages are that you need to be able to work through the pars plana and you have to be able to manipulate the lens in the eye and be able to handle it with a handshake technique, move the lens from one area in the eye to another area in the eye. You have to be able to take the lens from the anterior chamber and pass it through the sclera and into the pars plana and out through the incision,” Donnenfeld said.
A variant of the handshake technique eliminates the need for an assistant to hold the haptic during the procedure. Narang described the technique in a paper published in the Journal of Cataract and Refractive Surgery.
“When I do my no-assistant technique, we use the handshake technique,” Narang said. “This is actually a two-handed procedure where I do not need an assistant to help me out in the glued IOL procedure.”
Narang described the no-assistant technique, in which an IOL is manipulated into an eye that does not have a posterior capsule.
“There is an inherent fear in the mind of a surgeon that, whatever I do in this procedure, my haptic should not slip,” Narang said. “To overcome this, the surgeon or assistant always exerts a little bit more pressure on the haptic. You cannot afford to lose the intraocular lens because if the haptic slips, you will have an intraocular lens drop on the retina because there is no posterior capsule to support it.”
In the technique, the leading haptic is pulled and externalized. The trailing haptic is grasped with the glued IOL forceps and flexed into the eye until it reaches or passes the mid-pupillary plane. The left hand of the surgeon still holds the leading haptic. The trailing haptic is moved inferiorly toward the 6 o’clock position. The surgeon releases the leading haptic and introduces the forceps from the side port. The trailing haptic is transferred to the left hand.
“The moment I cross the mid-pupillary plane, the vector forces act in the opposite direction and cause the leading haptic to extrude more from the sclerotomy site,” Narang said.
The surgeon enters the eye from the right sclerotomy site with the forceps and catches the tip of the trailing haptic. The left hand, now free, is pulled from the eye to grasp the tip of the leading haptic. The trailing haptic is pulled and externalized.
In another study published in the Journal of Cataract and Refractive Surgery, Narang found that the no-assistant technique reduced haptic slippage, kinking and breakage compared with the original handshake technique.
“[We found] that the haptic-related problems are less in the no-assistant technique because, when you’re doing a glued IOL surgery, your assistant is grabbing the haptic and you are manipulating the trailing haptic,” Narang said. “Your assistant really does not know how much pressure is to be exerted on the haptic.”
Glued capsular hook, trocar anterior chamber maintainer
Jacob described a technique that uses a capsular hook to obtain glued transscleral fixation of the capsular bag in cases involving clinically significant subluxated cataracts.
“With less than a quadrant of subluxation, you can just put in a capsular tension ring and that’s enough,” Jacob said. However, when there is more than a quadrant of subluxation, the capsular bag must be fixated at the time of phacoemulsification or else phacodonesis may result.
The hook passes through a sclerotomy created under a scleral flap and engages the capsulorrhexis rim, providing scleral fixation. A standard capsular tension ring expands the capsular fornix. The glued capsular hook anchors the capsular bag to the sclera, providing vertical and horizontal stability, and stabilizes the bag intraoperatively and postoperatively, Jacob said. If more intraoperative support is needed, additional translimbal hooks can be used and removed at the end of surgery. The haptic of the transscleral hook is tucked into a scleral tunnel for postoperative fixation, and the scleral flap is closed with fibrin glue.
“It’s not difficult to do. You make a Scharioth tunnel, trim the haptic of the capsular hook to the desired length and just push the haptic into the tunnel,” Jacob said. “The problem with suturing rings and segments is that you need to pass a long needle into the anterior chamber, and it’s difficult to handle the needle holding it by its very tip and you often don’t get it absolutely where you want to. The glued capsular hook solves all of these problems. You can stabilize the capsule, do your phacoemulsification and put in an intraocular lens.”
Another recent innovation introduced by Agarwal is the use of a trocar anterior chamber maintainer (T-ACM) that helps in surgery. One should always have fluid in the eye rather than use viscoelastics, he said.
“If I am an anterior segment surgeon, I want fluid in the eye,” Agarwal said. “I make a knife entry into the cornea and then take an anterior chamber maintainer and put it into the eye.”
The problem, however, is that the knife entry can be too large or too small and not fit the anterior chamber maintainer.
“If it is too large, then it will leak; if it is too small, too narrow, I will be fighting to put the anterior chamber maintainer into the eye,” Agarwal said. The solution is to use a trocar anterior chamber maintainer.
Agarwal said he places a trocar cannula half a millimeter from the limbus.
“I am in the sclera, but I enter in front of the iris,” he said.
The advantage of the T-ACM is that it gets fixed and does not come off, and at the end of surgery, it can be easily pulled out. Agarwal said he uses it while doing suturing of the iris or pre-Descemet’s endothelial keratoplasty (PDEK).
Glued IOL scaffold technique
A glued IOL scaffold technique is particularly useful in cases that involve Soemmering rings and subluxated cataracts, Agarwal said.
“This cortical material cannot be removed with a phaco probe because it’s very thick,” he said. “Implanting an IOL behind the nucleus, the IOL now acts like a posterior capsule. Now I can go above the IOL and emulsify the nucleus because the IOL is acting like a scaffold.”
Jacob also said there are advantages of the glued IOL scaffold technique, particularly when removing retained nuclear fragments.
“What the scaffold technique does is decrease the chance of a nuclear drop because now you’ve got something behind the nuclear fragments that prevent them from falling down,” Jacob said.
Agarwal said he also uses the glued IOL scaffold technique in cases involving insufficient capsule and posterior capsule rupture when the nuclear fragments are still present.
“In such cases, I just affix the glued IOL and then remove the nuclear fragments, thus making life much easier,” he said. The fragments cannot fall into the vitreous because the glued IOL is behind the fragments and acts as a scaffold.
Combination with DMEK, PDEK
Glued IOLs can also be combined with Descemet’s membrane endothelial keratoplasty and PDEK, Agarwal said.
“In DMEK, I need something stable because when I put air in and if the eye is aphakic, the graft will go down. You need a support,” he said.
Agarwal described the role of a glued IOL in performing PDEK with air tamponade. The surgeon successively performs a vitrectomy, glued IOL fixation, pupilloplasty if necessary and PDEK.
“The glued IOL, since it is firmly fixed, acts like a trampoline. So, when I inject the air, the trampoline effect pushes the air against the graft. So, when it pushes against the cornea, the graft stays in place. Now, imagine if I had an aphakic eye with no capsule, my graft would have been on the retina postoperatively. Or, if I had a lens that is wobbly, like a sutured lens, it would not work. So, glued IOLs can be combined with corneal surgery, especially endothelial keratoplasties,” Agarwal said.
Jacob said an iridoplasty, when required, is vital to be performed when combining glued IOL with DMEK or PDEK.
“It is important to obtain a good separation of the anterior chamber from the posterior chamber. The pupil should cover the IOL optic well all around in order to have a stable and complete iris-IOL diaphragm. This is to obtain a good air tamponade for the graft postoperatively and to prevent air from migrating posteriorly behind the IOL, which can result in increased chances of graft detachment. For similar reasons, the IOL should also not be placed too far back from the iris plane to avoid posterior air migration, which can occur in these vitrectomized eyes that do not have an intact capsulo-zonular barrier,” she said.
Price said that in eyes with decompensated corneas and anterior chamber IOLs, he and his colleagues remove the anterior chamber IOL, implant a posterior chamber IOL and perform DMEK a month later. He said that some eyes with glued IOLs develop hypotony because of fluid leakage through stab incisions used to pull out the lens haptic.
“The incision that you’re making into the eye to bring the haptic out has to have a hole bigger than the haptic,” Price said. “Even with the scleral flap over it and sometimes with the glue, you can get some hypotony for 2 or 3 days. If you can get hypotony with an endothelial keratoplasty, the graft will likely detach. Each time you blink, it indents the cornea in a soft eye.”
Price noted that he performs Descemet’s stripping endothelial keratoplasty in eyes with all or part of the iris missing. In addition, in cases with all or part of the iris missing, the glued posterior chamber IOL is not enough to stop the donor graft from falling back. Price said he inserts artificial iris implants in many cases with missing irises.
“Now, the reason I’m pointing this out is that if your only barrier to keep an endothelial keratoplasty from falling backward is an IOL or an artifical lens, there is still an opening all the way around between the implants and wall of the eye, so that a graft can easily fall back to the retina if you let go. So don’t let go until have the graft fixed with a suture or air against the cornea,” Price said. – by Matt Hasson
- Agarwal A, et al. J Cataract Refract Surg. 2015;doi:10.1016/j.jcrs.2015.02.020.
- Agarwal A, et al. J Cataract Refract Surg. 2015;doi:10.1016/j.jcrs.2014.12.035.
- Agarwal A, et al. J Cataract Refract Surg. 2013;doi:10.1016/j.jcrs.2013.01.019.
- Agarwal A, et al. J Cataract Refract Surg. 2008;doi:10.1016/j.jcrs.2008.04.040.
- Jacob S, et al. J Cataract Refract Surg. 2015;doi:10.1016/j.jcrs.2014.12.035.
- Jacob S, et al. J Refract Surg. 2014;doi:10.3928/1081597X-20140527-04.
- Jacob S, et al. J Cataract Refract Surg. 2014;doi:10.1016/j.jcrs.2014.10.009.
- Jacob S, et al. Ocular Surgery News. Feb. 10, 2011;29(3):32.
- Narang P. J Cataract Refract Surg. 2015;doi:10.1016/j.jcrs.2015.02.020.
- Narang P. J Cataract Refract Surg. 2013;doi:10.1016/j.jcrs.2013.05.017.
- Narang P. J Cataract Refract Surg. 2013;doi:10.1016/j.jcrs.2012.11.001.
- Price MO, et al. J Cataract Refract Surg. 2005;doi:10.1016/j.jcrs.2004.12.060.
- Scharioth GB, et al. J Cataract Refract Surg. 2010;doi:10.1016/j.jcrs.2009.09.024.
- Scharioth GB, et al. J Cataract Refract Surg. 2007;doi:10.1016/j.jcrs.2007.07.013.
- For more information:
- Amar Agarwal, MS, FRCS, FRCOphth, can be reached at Dr. Agarwal’s Eye Hospital, 19 Cathedral Road, Chennai 600086, India; email: email@example.com.
- Eric D. Donnenfeld, MD, can be reached at Ophthalmic Consultants of Long Island, 2000 North Village Ave., Rockville Centre, NY 11570; email: firstname.lastname@example.org.
- Soosan Jacob, MS, FRCS, DNB, can be reached at Dr. Agarwal’s Eye Hospital, 19 Cathedral Road, Chennai 600086, India; email: email@example.com.
- Priya Narang, MS, can be reached at Narang Eye Care and Laser Center, 2nd Floor, AEON Complex, Vijay Cross Roads, Ahmedabad, 9. Gujarat, India; email: firstname.lastname@example.org.
- Francis W. Price Jr., MD, can be reached at Price Vision Group, 9002 N. Meridian St., Suite 100, Indianapolis, IN 46260; email: email@example.com.
Disclosures: Jacob reports she has a patent pending for modified versions of the glued capsular hook. Agarwal, Donnenfeld, Narang and Price report no relevant financial disclosures.
When is it advisable, or not advisable, to choose glued intrascleral posterior chamber IOL implantation?
Gluing most preferable when capsule is insufficient
Proceeding from most to least desirable, we can rank IOL desired positions from: 1. In the stable, intact capsular bag with 360° intact zonules and capsulorrhexis cover of the IOL edge. 2. As 1, but with something imperfect. 3. Haptics in the bag with the IOL captured in a posterior capsulorrhexis, no vitreous loss. 4. Haptics in the sulcus with the optic captured in the anterior capsulorrhexis. 5. Sulcus IOL placement. 6. Roughly equal between (a) glued posterior chamber intrascleral fixation and (b) iris claw IOLs. 7. Sutured PC IOL. 8. Anterior chamber IOLs.
The last three choices are in play when insufficient capsular remnants remain to enable the first five choices. The choice between 6a and 6b is made on the presence or performance of a complete vitrectomy, leaving the space behind the iris clean and free of vitreous, and the skill of the surgeon in the performance of the handshake technique of Agarwal in order to achieve the IOL implantation safely and without complications.
It is also important to carefully examine the limbus in advance to ensure that the intended IOL haptic placement area is free and unencumbered by such things as previous traumatic coloboma repair sutures, etc. Glued scleral fixation of PC IOLs is preferable to scleral suturing because of the advantage of less resultant IOL tilt.
Steve A. Arshinoff, MD, FRCSC, is an OSN Cataract Surgery Board Member. Disclosure: Arshinoff reports no relevant financial disclosures.
More choice of lenses, tools is warranted
Later in this issue, I blog about my early experience with glued IOLs. This procedure clearly has value but more tools are needed to make the procedure easier and offer alternate solutions.
Three-piece lenses available in the U.S. are generally no larger than about 13 mm, and about 1 more millimeter of overall length would allow much easier and more secure haptic fixation. Also on my wish list would be an extended range of powers in these in long lenses because some of these eyes have unusually high axial myopia.
Another notably missing tool in the U.S. is a pseudophakic claw-type IOL designed like the Artisan phakic implant. In Europe, these are regularly fixated to the back of the iris, and a number of studies have shown long-term stability and ease of use as a safe, posterior chamber, iris-fixated IOL.
Meanwhile, while we wait for the approval of these IOLs, the glued IOL technique described by Amar Agarwal, Soosan Jacob and others, should certainly be in the wheelhouse of versatile anterior segment surgeons.
John A. Hovanesian, MD, FACS, is OSN Cataract Surgery Section Editor. Disclosure: Hovanesian reports no relevant financial disclosures.