By Laird Harrison
New technology can improve outcomes of complex cataract cases in glaucomatous eyes, said Alan Crandall, MD. “There are a bunch of new tools that we have that makes it a lot easier to do these cases,” he added.
Dr. Crandall, professor and senior vice chairman of ophthalmology and visual sciences, and director of glaucoma and cataract at the John A. Moran Eye Center, University of Utah, Salt Lake City, explained the advantages of the latest medical gadgets.
Watch as Alan Crandall, MD, discusses the complexities encountered with cataract surgery in glaucoma patients.
For example, the Active Fluidics Technology of the Centurion Vision System (Alcon Laboratories) “makes chamber maintenance much easier than our old systems,” he said. He called Whitestar Signature (Abbott Medical Optics) “a beautiful machine as well.”
Also on the shopping list for surgeons who treat cataracts in glaucoma cases, Dr. Crandall added capsular tension rings and intraocular stains. “Trypan Blue helps visualization in some of these typical cases,” he said. “You need to have vitreous stain available in case you run into issues.”
A viscoadaptive agent (OVD) is also critical, he said. “You can use it to maintain the chamber and protect the vitreous from coming forward.” He mentioned both Healon5 (Abbott) and DisCoVisc (Alcon).
To manage the capsule correctly, Dr. Crandall likes to use the Ahmed Capsular Tension Segment (FCI Ophthalmics). He is also a fan of the capsular anchor, “if you happen to have access to European devices.”
Capsular tension rings (CTRs) come in handy for a variety of complex cases, he said, listing Marfan’s syndrome, pseudoexfoliation, and trauma cases. “There is some indication that the high myopes would benefit from it because it stabilizes the anterior segment and may decrease the rate of retinal detachment,” he added.
The timing of placement when using CTRs is critical. “If you put it in prior to phaco, you have better stability, but it can be very difficult to put it in with a hard nucleus or a large one,” Dr. Crandall pointed out. “It makes rotation and removal difficult.”
CTRs are contraindicated in instances of anterior capsular tear and posterior capsular rent, said Dr. Crandall. But if physicians can convert a posterior capsular rent to a full circular capsulotomy, they can still use the CTR.
For large subluxations, Dr. Crandall advocates the new Type 1G Cionni ring (FCI Ophthalmics). “It’s a lot more flexible and it’s easier to put in,” he said. He also uses the Malyugin Ring (MicroSurgical Technology), which can be injected.
Ahmed Capsular Tension Segments are handy as well, he said. “The nice thing about them is you can put them in if you have an anterior capsular tear, because they don’t put stress on the system.”
To start the capsulorhexis, Dr. Crandall likes to use the Mackool Hook (FCI Ophthalmics) or hooks by MicroSurgical Technology. “They’re very easy to get in, very easy to get out, and really maintain the bag very well,” he said.
Regarding pseudoexfoliation cases, Dr. Crandall has made changes in his approach since 2014. He assesses the zonules more carefully, looking for chamber asymmetry.
“Then, you want to do elegant surgery,” he said. “Now, we always want to do elegant surgery. But here you try to really minimize the stress.”
CTRs may help decrease phimosis but they don’t protect against the lens dropping, he pointed out.
Dr. Crandall emphasized the importance of expanding pupils in these cases. “We used to teach courses on doing a phaco in a 2 mm eye,” he said. “Yes, you can do that. But in pseudoexfoliation, it’s a big mistake because you leave too much material in there. You can’t get all of the cortex out. You leave lens epithelial cells.”
He advocated visco-dissection to help rotation. “Bimanually rotate so that there is no pressure on the zonules while you’re doing that,” he advised.
Anterior lens epithelial removal and the use of capsular tension rings when indicated are important because of the stress caused by rotation even with a small lens. “You’ve got to get the bag open, so you can remove all the lens epithelial cells,” he said. “So I use Malyugin rings or other types of rings because of that.”
Never come out of a pseudoexfoliation eye without letting the bag come forward, Dr. Crandall advised. “I use an (OVD) after every single maneuver,” he said. “We’ll see in 10 years if this makes a difference.”
He recommended tangential rather than radial aspiration. The best way to decrease zonular stress, Dr. Crandall said, is to use a femtosecond laser, followed by UltraChopper (Alcon), followed by vertical chopping, followed by horizontal chopping.
“In summary, glaucoma is fun,” Dr. Crandall said. “It always has sclera problems. Capsules are weak. And they’re harder cases!”