EyeWorld Asia-Pacific September 2019 Issue

EWAP SEPTEMBER 2019 65 DEVICES Pharmacological vs. mechanical by Rich Daly EyeWorld Contributing Writer Pupil dilating devices Contact information Henderson: bahenderson@eyeboston.com Tipperman: rtipperman@mindspring.com This article originally appeared in the May 2019 issue of EyeWorld . It has been UNKIJVN[ OQFKƂGF CPF CRRGCTU JGTG YKVJ permission from the ASCRS Ophthalmic Services Corp. A mid the proliferation of pupil dilating devices, it remains important to know when cataract patients are best served by them or pharmacological options. If the patient’s pupil dilated well in the preop visit but does not seem as dilated on the operating table, Bonnie Henderson, MD, augments the topical dilation drops with intracameral epinephrine. “The preservative-free epinephrine can be drawn directly from the vial and diluted 1:4 with balanced salt solution and injected into the anterior chamber,” Dr. Henderson said. “I only inject a small amount— about 0.3 cc—turn off the microscope, and allow it to work for 1 minute before continuing the case.” The injection of epinephrine follows injection of preservative- free lidocaine into the anterior chamber. “I have found that epinephrine alone works well and does not seem to cause any discomfort to the patient,” Dr. Henderson said. Richard Tipperman, MD, tries adjuvant pharmacological substances for small pupil cases and uses them prophylactically in all femtosecond cases. Additionally, surgeons at Wills Eye Institute use epi-Shugarcaine solution (epinephrine and ˆ`œV>ˆ˜i ˆ˜ vœÀ̈wi` L>>˜Vi` Ã>Ì solution) to enlarge pupils during cataract surgery. Mechanical devices Dr. Henderson turns to a mechanical device to help with pupil dilation and maintenance in other circumstances. In the preop evaluation in the clinic, Dr. Henderson evaluates the level of pupillary dilation. She also notes any medications the patient is taking that might affect the pupil. If the pupil does not dilate well in the clinic, Dr. Henderson will plan to use a device. “However, if the pupil dilated ÃÕvwVˆi˜ÌÞ LÕÌ Ì…i «>̈i˜Ì ˆÃ on a medication that can cause yœ««Þ ˆÀˆÃ Ãޘ`Àœ“i] ܈…>Ûi the device ready in the operating room,” Dr. Henderson said. v ̅i ˆÀˆÃ Ãii“à yœ««Þ >Ì Ì…i beginning of surgery—even after the injection of intracameral lidocaine or viscoelastic—she implants a pupillary dilation device before creating the capsulorhexis. “If the capsulorhexis is already made and the pupil starts to constrict, it is still possible to use hooks or a ring at that time,” Dr. Henderson said. “However, great care must be taken to avoid capturing the edge of the capsule while attempting to capture just the edge of the pupil.” Dr. Tipperman said a poorly dilating pupil clearly is the leading indication in such situations but noted that there are additional considerations as well. “I’m more likely to use a mechanical device with a ‘small pupil plus,’ which is a small pupil plus a very dense lens, a small pupil plus pseudoexfoliation, or a small pupil plus a very shallow anterior chamber,” Dr. Tipperman said. Device selection When the pupil alone is the problem, Dr. Henderson prefers a ring type of device. “However, if I suspect that the zonules are also weak, then I prefer hooks so that I can use the hooks to keep the pupil dilated and to support the capsular bag. I like the adaptability of hooks,” Dr. Henderson said. “Also, with hooks, I can choose the location of the placement and can choose how many to use.” Another situation in which Dr. Henderson prefers to use hooks over rings is during scleral wÝ>̈œ˜ œv >˜ " ° “It is sometimes helpful to use a hook to give additional exposure to the area where ̅i…>«ÌˆV ˆÃ ̜ Li wÝ>Ìi`]» À° Henderson said. Among situations or patient types where Dr. Henderson “œ`ˆwiÅiÀ ÕÃi œv > `iۈVi ̜ dilate the pupil is during manual small or large incision cataract Pupil expansion with the Malyugin ring. Source: Uday Devgan, MD continued on page 68