In capsular staining, ophthalmic surgeons usually introduce an air bubble and then either indocyanine green (ICG) or trypan blue. This technique, however, is not without risk of corneal toxicity or uncontrolled dyeing of the anterior chamber's tissues that can decrease visualization for phacoemulsification and produce unsightly staining of the iris.
After learning of an innovative technique last year from Robert Osher, MD,1 I have been creating the capsulorhexis in cases of mature cataract with ICG under Healon5 (Advanced Medical Optics, Inc., Santa Ana, CA), my viscoelastic of choice for standard cataracts as well. This approach saves time, reduces the risk to the corneal endothelium, and thus speeds visual recovery in challenging cataract cases.STEP BY STEP
After creating a paracentesis port with a 1-mm diamond knife, I introduce Healon5 into the anterior chamber. During the maneuver, aqueous humor must be carefully released from the anterior chamber to ensure that a sufficient quantity of Healon5 is delivered there, where it should coalesce into a uniform bolus to protect the corneal endothelium and maintain even pressure on the anterior capsule. Because this viscoelastic has a higher molecular weight than traditional viscosurgical devices, it is important to avoid overfilling the chamber and causing zonular dialysis.
Next, I use a 2.5- to 3.5-mm trapezoidal diamond knife to make a two-plane, self-sealing clear corneal wound. If a significant amount of Healon5 is lost during this maneuver, I will reintroduce the cannula with viscoelastic to inflate the chamber by the appropriate amount. A gentle sweeping motion with the cannula displaces the Healon5 over the anterior capsule in the area where I want to create the capsulorhexis. This maneuver creates a space in which to deliver the dye and simultaneously creates an escape route for excess dye. In his video, Dr. Osher instills BSS under the bolus of Healon5.1 I have found that this irrigation can create crevices within the bolus of Healon5 into which the dye can escape and come in contact with the corneal endothelium. Therefore, rather than perform this maneuver, I avoid irrigation with BSS and directly deposit the ICG underneath the bolus of viscoelastic, over the anterior capsule (Figure 1). Finally, I complete the capsulorhexis without removing the dye (Figure 2).CASE EXAMPLE
By using Healon5, I can safely create a capsulorhexis of any size without clouding of the anterior chamber, a problem that I have found to be common with other viscoelastics. I then perform my standard phacoemulsification procedure.
I used the aforementioned technique when performing cataract surgery on a 61-year-old black female who had hand-motion vision in her left eye. On postoperative day 1, her UCVA had improved to 20/20, and her cornea was crystal clear.
Mitchell C. Shultz, MD, is in private practice and is Assistant Clinical Professor at the Jules Stein Eye Institute, University of California, Los Angeles. He states that he holds no financial interest in the products or companies mentioned herein. Dr. Shultz may be reached at (818) 349-8300; firstname.lastname@example.org. Osher RH. Presentation 11. Video Textbook of Viscosurgery. 2004;vols. 9&10.