EyeWorld India March 2014 Issue

March 2014 12 EWAP FEAturE Limbal, pars plana approaches useful in complicated cataract cases by Erin L. Boyle EyeWorld Senior Staff Writer Cataract surgeons should know how to proceed for best results with either a limbal or pars plana approach W hen cataract surgeons encounter posterior chamber (PC) rupture and vitreous loss, deciding whether to use a limbal approach vs. a pars plana approach in a vitrectomy procedure depends on the specifics of the case, experts say. “It’s not which do you do, it’s when do you do either one or the other. It depends on the situation,” said Garry P. Condon, MD, associate professor, College of Medicine, Drexel University, Pittsburgh, Pa., U.S. “I think it behooves us as anterior segment surgeons in this day and age with the beautiful instrumentation that we have now to do [both] so that we can be comfortable.” Cataract surgeons should be prepared for these complications to happen at any time, with instrumentation and additional viscoelastic agent readily at hand to proceed, he said. The many advantages of using small gauge vitrectomy probes have enhanced the process, Dr. Condon said, including for cataract surgeons. The limbal approach provides access through the conjunctiva at the limbus, or the corneo-scleral junction. The pars plana approach allows access to the vitreous through the pars plana, which is 3–5 mm behind the corneal limbus. Both approaches have advantages, physicians say. “Vitreous loss for the anterior segment surgeon can obviously be a stressful experience, but an event all cataract surgeons face at some point in their career. Being prepared can improve the patient’s outcome and reduce the surgeon’s anxiety,” said Howard F. Fine, MD , clinical associate professor, Rutgers University, Robert Wood Johnson Medical School, New Brunswick, NJ, U.S. Dr. Fine is a retina specialist. For cataract surgeons, there can be real dangers in addressing these cases, said cataract specialist Steven H. Dewey, MD, Colorado Springs Health Partners. “Anyone who is not fully trained in retinal procedures has the concern of incarcerating vitreous in the pars plana incision,” Dr. Dewey said. “Or iatrogenic retinal tears. These are things that don’t happen with a tremendous amount of frequency but certainly can.” What to do A cataract surgeon’s first step when encountering PC rupture and vitreous loss during cataract surgery should be to determine precisely what is happening, Dr. Dewey said. “Determining which approach is going to be better, I assess how far along in the process of damage things have gone,” Dr. Dewey said. “If the tear is very small but the vitreous prolapse is significant and it’s going to impede my ability to place the lens implant in the capsulorhexis, many times it’s just a matter of getting it in the sulcus with vitreous strands coming through the pupil; then the first decision is, you go to the pars plana.” Dr. Condon also suggested assessing the situation to determine how to best move forward and which approach to choose. He said to not immediately pull out the phacoemulsification instrument if you see capsular rupture vitreous presentation. Instead, stop. Stabilize the situation with viscoelastic agent. Then remove the phaco instrument. “I assess what’s really happened, and how can I salvage what I’m left with and make the best possible outcome for this patient. That’s the difference between being comfortable at Vitreous loss after posterior capsule rupture, pictured here, can be cause for an anterior vitrectomy using one of two approaches, either limbal or pars plana. Source: David Allen, FRCOphth AT A GLANCE • Both pars plana and limbal approaches can be effective for different cases. • The limbal approach might provide a better comfort level to anterior segment surgeons. • The pars plana approach has many advantages but is potentially more difficult for anterior segment surgeons. • Refer to retina specialists for the following: posterior dislocation of large cataract fragments or the IOL, suspected retinal tear or detachment, or choroidal hemorrhage.