During Friday’s Retina Subspecialty Day, Claus Eckardt, MD, presented reasons that the bag-in-the-lens (BIL) implant is an ideal choice for patients having combined phacoemulsification and vitrectomy, or phacovitrectomy. This lens “guarantees good and stable centering of the IOL,” he noted, and produces satisfying outcomes even in the presence of gas or silicone oil.
What is the need? In eyes undergoing a combined procedure, the gas bubble can push a standard lens partially out of the bag. The result? Early opacification of the posterior capsule after a few months, which can occur with almost all types of lenses.
To avoid this complication, Dr. Eckardt prefers to utilize the BIL implant (Morcher). Surgery requires two capsulotomies—one anterior and one posterior. Although the procedure involves an extra step, surgeons often achieve a rewarding postoperative result that makes it worthwhile.
Two rhexes, one lens. The BIL implant—often referred to as the Tassignon lens after its inventor, Marie-José Tassignon, MD, PhD—is a hydrophilic IOL that has two anterior and two posterior lips, and a groove that encircles the entire lens. When in place, the edges of the two capsules slide into the groove, sealing the capsular bag and the proliferating lens epithelial cells in the rim of the lens.
Advantages. The BIL offers several advantages in eyes undergoing phacovitrectomy. Among them are excellent centering and no capsular opacification. A particularly important feature is that posterior synechiae never develop because the posterior and anterior capsules are glued together, eliminating contact with the iris. This avoids complications such as iris bombé. Finally, the lens can easily be exchanged through a simple surgical maneuver, even after a period of several years.
Drawbacks. There is no question that the surgical technique is more challenging when the pupil is small and the zonules are weak. Postoperatively, surgeons should avoid dilating the pupil too much in the first few days after surgery, as there is a risk of iris capture. Calcification of the acrylic lens is theoretically possible, but Dr. Eckardt has yet to encounter this complication in the 3,000 eyes that he has implanted with the BIL lens. In addition, patients will have to pay more for the BIL than other IOLs.
Real-world outcomes are promising. Dr. Eckardt has tried this implant not only in straightforward cases of macular puckers and holes but also in more challenging eyes with proliferative vitreoretinopathy or proliferative diabetic retinopathy that need repeated vitrectomies with oil and gas tamponade.
“No matter how advanced the vitreoretinal pathology is, there is almost a guarantee of a nice and stable centering of the lens,” concluded Dr. Eckardt. “One eye looks like the other, and they stay so for years and probably for the rest of the patient’s life.” —Keng Jin Lee, PhD
Financial disclosures. Dr. Eckardt: Vitreq: P.
Disclosure key. C = Consultant/Advisor; E = Employee; L = Speakers bureau; O = Equity owner; P = Patents/Royalty; S = Grant support.
Read more news from AAO 2019 and the Subspecialty Day meetings.