EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.
Issue link: https://digital.eyeworld.org/i/387844
71 EW FEATURE Figure 5: Photo of the lens against the red refl x, highlighting the pattern of pseudoexfoliation material on the anterior lens capsule (close-up of Figure 4) Source (all): David G. Heidemann, MD Figure 4: Low power photo of the lens against the red refl x showing the pseudoexfoliation material on the anterior lens capsule and transillumination defects in the peripheral iris margin Dr. Hart chooses to place CTRs in all of his pseudoexfoliation pa- tients. Dislocations are impossible to predict, he said, and with a CTR in place, the surgeon has 360 degrees of access to refixate the lens if that happens. This is especially helpful when considering that many pseu- doexfoliation patients are at risk of developing glaucoma—ideally, the lens repair should allow the patient to undergo glaucoma surgery later if it is needed, he said. A CTR also keeps the capsular bag open if the lens dislocates, so it is much less likely that the vitreous will prolapse during the lens repair, he added. Dr. Gedde, on the other hand, is selective in the use of CTRs in pseudoexfoliation patients, as there is potential for iatrogenic capsule and zonule injury with CTR insertion. He will use a CTR if there is less than or equal to 4 clock hours of zonular dialysis and/or mild phacodonesis, and a sutured modified CTR or capsule tension segment for more severe dialysis. CTRs redistribute stress among all the zonules and reduce rates of asymmetric capsular contraction, said Dr. Giaconi, but not all pseu- doexfoliation patients have weak zonules and not all will end up with a dislocated lens. She will place a CTR if she sees zonular dialysis in one quadrant or if she suspects mild phacodonesis. Surgeons also face the challenge of determining the optimal time to insert the device during the proce- dure. "A CTR may impede cortical removal, and I prefer to delay im- plantation as long as possible during the case for this reason," said Dr. Gedde. "I generally put them in after I've taken the lens and the cortex out," said Dr. Hart. IOL choice Since accommodating lenses depend on normal capsule-zonule function and multifocal, toric, and aspheric monofocal lenses depend on good centration, these lenses are con- traindicated in pseudoexfoliation patients, said Drs. Hart, Gedde, and Giaconi. The surgeons also tend to use 3-piece IOLs more often than 1-piece IOLs because they are more rigid and can be more easily fixated if the lens dislocates. One-piece lenses tend to tilt and torque when sutured into place, said Dr. Hart, which can cause vision problems later on for the patient. October 2014 Complex cataract cases "Soft 1-piece acrylic lenses are easy on the zonules during lens placement intraoperatively so they avoid additional stress on the zonules, but they don't resist capsular contraction very well," Dr. Giaconi said. "The 3-piece lenses can resist capsular contraction, at least in the areas of the haptics, more than the 1-piece lenses." Postoperative implications "These patients can have great vision postoperatively, but one must be aware that this can change over time since the zonulopathy is progressive," Dr. Giaconi said. As a result, pseudoexfoliation patients must be followed closely to moni- tor IOL position as well as to check for inflammation and elevations in IOP—often for life. "Complaints of decreased vision after cataract surgery in pseudoex- foliative eyes aren't always due to posterior capsule opacity, as they are in many pseudophakic eyes," Dr. Giaconi said. If the patient has vision problems, the surgeon must look specifically for lens subluxation or dislocation and correct the prob- lem as soon as possible. Dr. Gedde uses topical steroids more frequently and for a longer du- ration in pseudoexfoliation patients, as abnormalities in the blood-aque- ous barrier make them more prone to postoperative inflammation. Pseudoexfoliation is a risk factor for glaucoma, so IOP should also be monitored after surgery. "Combined cataract and glau- coma surgery may be indicated in select patients with pseudoexfolia- tion, depending on the IOP level, medication tolerance, stability of glaucoma, and degree of glaucoma- tous damage," Dr. Gedde said. With these considerations, close monitoring of the patient after sur- gery is essential to track the progress of the disease and address any com- plications that may arise. EW Editors' note: The physicians have no financial interests related to their comments. Contact information Hart: j.c.hartjr@sbcglobal.net Gedde: sgedde@med.miami.edu Giaconi: Giaconi@jsei.ucla.edu