It’s time to evolve routine cataract surgery: abandon the bag, save the hyaloid.

The most common complication of modern, lens-in-the-bag cataract surgery is secondary cataract. Visual-axis opacification, despite modern attempts to limit it — with square-edged optics, meticulous cortical cleanup and rhexis optic overlap — still occurs in up to 40% of adults and 100% of pediatric patients.¹

Until now, the solution has been to allow a second period of glare and decreased acuity to proceed as the visual axis re-opacifies, followed by the seemingly simple Nd:Yag laser capsulotomy. We glibly accept as necessary disruption of the precious anterior hyaloid, the barrier which defines the two-chambered eye.²

We have grown accustomed to a small clear opening in a sea of fibrosis, floaters and accept as necessity an increased risk of CME, retinal detachment and IOP increase. Pediatric patients are subjected to routine primary anterior vitrectomy and posterior vitrectorhexis, considered a complication in adults. Is it surprising, then, that this technique, where the immature trabeculum is exposed to vitreal elements, is associated with increased inflammation and up to a 15% incidence of consecutive open-angle glaucoma, in this congenital cataract cohort?³ Our present day standard technique should not, and need not, define the state of the art any longer.

In this article, in addition to encouraging the routine use of posterior optic capture, or buttonhole, I shall propose consideration of a technique that will eliminate secondary cataract and possibly reduce the threat of other adverse events such as bag-lens subluxation — while retaining the invaluable hyaloid for the life of the patient.

OPTIONS

Four people are primarily responsible for much of the work leading to what I call sulcus-based bicapsulotomy capture (SBCC). Howard Gimbel, MD, first described posterior continuous curvilinear capsulorhexis (PCCC) and posterior optic capture.⁴ Rupert Menapace, MD, who regularly uses this technique in adults, has published prospective fellow-eye studies of efficacy and safety. His term for this procedure is posterior optic buttonhole (POBH).⁵ Burkhard Dick, MD,⁶ pioneered use of the femto laser sterile redocking (off label) for posterior capsulotomy and Marie-Jose Tassignon, MD,⁷ with her bag-in-the-lens (BIL) technique and use of ring caliper, has shown long-term efficacy even in infants with the lens optic in Berger’s space. From their work, we know two things: we can eliminate secondary cataract for patients of all ages and save the hyaloid.

Learning curve is always an issue. But, since we are all facile with anterior capsulotomy, it isn’t rocket science to apply similar principles to the posterior capsule (PC) with a few added skills. Mastering the PC is valuable for the evolution of routine cataract surgery, but is of practical use today to achieve best outcomes in complex situations and when laser capsulotomy isn’t feasible.

Posterior capsulorhexis, no question, requires a deft touch. The PC is thinner (4 to 6 u) and more elastic than the anterior capsule. Most importantly, Berger’s space, defined by Wieger’s ligament, may need enlargement with OVD to separate the posterior capsule from the delicate anterior hyaloid behind it, preventing vitreous prolapse.

HOW TO ELIMINATE SECONDARY CATARACT

Mastering the technique would allow all surgeons to: convert inadvertent PC tears; make unstable toric lenses stay put; immediately restore vision to patients with unpolishable posterior plaques; and allow one anesthetic event for cataract patients who can’t sit still for a laser posterior capsulotomy.

After standard lens removal through a 5-mm anterior capsulotomy (via manual technique, femto laser, or, in the future, other anterior capsulotomy devices) the anterior and posterior capsules may be polished with the surgeon’s preferred method for 360 degrees. An OVD is placed into the sulcus to flatten together the anterior capsule rim and posterior capsules. The surgeon uses a 30-g needle – bevel up – to lift and puncture the central posterior capsule, lifting it away from the hyaloid, thereby creating a flap. Cohesive OVD is instilled between the anterior hyaloid and posterior capsule to define Berger’s space, pushing the hyaloid out of harm’s way to its border at Wieger’s ligament. A 5 mm central PCCC is created.

For a standard buttonhole procedure, the bag fornix is then opened with OVD, the implant injected into the bag and the optic is gently tucked under the PCCC’s edge, with pressure 90 degrees away from the optic-haptic junction on both sides of the optic to capture it into Berger’s space, leaving the haptics in the bag. This creates the same cat-eye appearance of the PC as we expect to see during anterior optic capture while leaving the round anterior capsulorhexis undisturbed.

Peer reviewed literature tells us that there is no increase in CME, inflammation, RD or IOP rise with this method, and we can expect zero incidence of visual axis opacity.^5,8

SULCUS BICAPSULOTOMY CAPTURE

I propose, rather than placing haptics in the bag and the optic in Berger’s space, that a three-piece lens be implanted with haptics in the sulcus and then the optic captured FIRST through the anterior capsulorhexis and also through the posterior capsulorhexis into Berger’s space, sealing the two capsules together in a similar manner to the BIL.

I hypothesize this technique will result in the most stable lens possible at the plane of the bag, zero posterior capsule opacification even in pediatric cataract, and will allow potentially flexible capsules equator to equator. Though a Soemmering’s ring may form, as with the BIL design it would be confined to the equatorial space by the optic capture which seals the anterior and posterior capsule edges, thus eliminating antigen leakage from the bag.⁹ Unlike with BIL, the lens’ stability is not dependent entirely on the zonules and a perfectly centered capsulotomy for centration. Rather, the lens’ centration is based on the fit in the sulcus. Unlike today’s standard lens in the bag, the continuous curvilinear capsulorhexis is stented by the optic and thus phimosis is excluded.¹⁰ I believe this will eliminate late bag-lens subluxations as I have seen with anterior optic capture in my patients with loose zonules. (I have a video regarding this on the ONE network; http://tinyurl.com/m2vd6qb )

With SBCC, the capsule should remain flexible and clear, as metaplasia is not stimulated due to the minimal contact between IOL and lens epithelial cells. I believe there is a chance that, as long as Wieger’s ligament remains intact, accommodative movement could happen; Dan Goldberg has described that such movement could be enhanced by extended depth of focus lens design.¹¹ An added advantage is eliminating the need for a square edge in an IOL implanted with this technique thereby reducing dysphotopsia. Another hypothesis: Though any current three-piece IOL would suffice, I believe the surgical goal will drive future IOL design and permit toric implantation as well.

Most importantly: So long as the optic is not PMMA (which has been shown to cause opacity of the vitreous face in infants), no patient would need a secondary Nd:Yag capsulotomy and the hyaloid would theoretically remain intact, protecting the posterior segment for life. SBCC has special appeal for refractive lens exchange, since stray light studies have shown patients have superior vision when the posterior capsule is absent compared to even “clear” PC with 20/20 Snellen acuity. The technique would reduce risk for pseudoexfoliation, high myopes and pediatric eyes; in fact, for every cataract patient.

To my knowledge, no one has suggested SBCC as a planned routine procedure (first described in 2004 by Brian DeBroff, MD, and Dr. Gimbel, with other methods of capture for pediatric cataract with anterior vitrectomy).¹²

Available IOLs can be employed. I have seen excellent long-term results in my own practice in rare complex trauma cases where I used the technique as a rescue. Tom Oetting, MD, has performed SBCC with a quiet outcome and clear visual axis without phimosis beyond six months in a pediatric monocular uveitis patient. (Paper in writing)

The main disadvantage of SBCC is that lens exchange would likely require an anterior vitrectomy, which could be done by one-port pars plana vitrectomy in a controlled manner before uncapturing the IOL. Coming technologies, such as refractive index shaping, will eliminate this issue.

THE POSSIBILITIES

For many surgeons, posterior capsule management is a bold new territory. These techniques should be mastered now. While the loss of Nd:Yag capsulotomy income in a fee-for-service medical economy could be a deterrent, it would save Medicare, or any socialized system, billions of dollars and be a blessing for the developing world.

I feel certain we will find that sparing the hyaloid and abandoning the bag for the optic in Berger’s space will confer myriad advantages and usher in a new era for cataract surgery as a final visual rehabilitation. OM

REFERENCES

1. Awasthi N, Guo S, Wagner BJ. Posterior Capsular Opacification: A problem Reduced but Not Yet Eradicated. Arch Ophthalmol. 2009;127:555-562.
2. De Groot V, Hubert M, Van Best JA, et al. Lack of fluorophotometric evidence of aqueous–vitreous barrier disruption after posterior capsulorhexis. J Cataract Refract Surg. 2003; 29:2330–2338.
3. Swamy BN, Billson F, Martin F, et al. Secondary glaucoma after paediatric cataract surgery. Br J Ophthalmol. 2007; 91:1627-1630.
4. Gimbel HV. Posterior continuous curvilinear capsulorhexis and optic capture of the intraocular lens to prevent secondary opacification in pediatric cataract surgery. J Cataract Refract Surg. 1997;23 (Suppl) 1:652–656.
5. Menapace R. Posterior capsulorhexis combined with optic buttonholing: an alternative to standard in-the-bag implantation of sharp-edged intraocular lenses? A critical analysis of 1000 consecutive cases. Graefes Arch Clin Exp Ophthalmol. 2008;246:787–801.
6. Dick HB, Schultz T. Primary posterior laser-assisted capsulotomy. J Refract Surg. 2014; 30:128–133.
7. Tassignon MJ, De Veuster I, Godts D, et al. Bag-in-the-lens intraocular lens implantation in the pediatric eye. J Cataract Refract Surg. 2007;33:611–617.
8. Stifter E, Menapace R, Kriechbaum K, Luksch A. Posterior optic buttonholing prevents intraocular pressure peaks after cataract surgery with primary posterior capsulorhexis. Graefes Arch Clin Exp Ophthalmol. 2010; 248:1595-1600.
9. Werner L, Tassignon MJ, Zaugg BE, De Groot V, Rozema J. Clinical and histopathologic evaluation of six human eyes implanted with the bag-in-the-lens. Ophthalmology. 2010;117:55-62.
10. Devranoglu K, Ozdamar A, Yurtsever AK, et al. Intraocular lens optic capture in eyes with zonular weakness in cataract patients. J Cataract Refract Surg. 2013; 39:669-672.
11. Goldberg DB. Computer-animated model of accommodation and theory of reciprocal zonular action. Clin Ophthalmol. 2011; 5:1559-1566.
12. Gimbel HV, DeBroff MB. Intraocular lens optic capture. J Cataract Refract Surg 2004; 30:200–206.

Dr. Arbisser is adjunct professor at Moran Eye Center, University of Utah. Contact her at: drlisa@arbisser.com. Dr. Arbisser and an international faculty will be teaching a course, for the first time: Mastering the Posterior Capsule: Thinking out of the Bag, Paradigm Change, AAO 2017.

Financial disclosure: Dr. Arbisser is a consultant to and stockholder in Mynosys.