3007: Artificial iris with strategic cut-outs

Uday Devgan MD

3007: Artificial iris with strategic cut-outs

Close-up view of an artificial iris with strategic cut-outs, demonstrating the use of a trephine to shape the implant for optimal results during an eye surgery.

Managing a patient with aniridia requires a highly customized approach to anterior segment reconstruction, specifically when shaping and placing an artificial prosthetic iris implant. Depending on the remaining anatomical structures, the prosthetic can be positioned either within the ciliary sulcus or directly inside the capsular bag. For the sulcus fixation approach demonstrated in this case, a trephine is used to create strategic peripheral cut-outs, which prevent the implant from compressing the ciliary processes and obstructing the aqueous flow. Conversely, when the device is placed inside a secure capsular bag, it is simply trephined to match the internal dimensions of the bag and left uniformly round without any scalloped edges. Watch the clip to study the delicate manipulation, trephination technique, and insertion mechanics required to safely deploy this therapeutic implant. What has been your clinical experience with long-term intraocular pressure control and centration when comparing sulcus versus capsular bag placement for these artificial iris devices? Please comment your insights below.

video link here

Published by Uday Devgan MD

Professor Uday Devgan MD is a Los Angeles Cataract Surgeon who authors CataractCoach.com to teach the best techniques of Cataract Surgery to Eye Surgeons from around the world.

1 Comment

  1. This is from Steve Safran …..I just reached out to Mike Snyder and he asked me to post the following comments from him. He tried to post but for some reason he had computer issues doing so:
    There are some meaningful concerns, only some of which are unique to this case (#3007):
    1) Trypan blue reduces elasticity of the anterior capsule (Dick HB, Aliyeva SE, Hengerer F. Effect of trypan blue on the elasticity of the human anterior lens capsule. J Cataract Refract Surg. 2008 Aug;34(8):1367-73. doi: 10.1016/j.jcrs.2008.03.041. PMID: 18655989) and congenital aniridics have very thin capsules (Schneider S, Osher RH, Burk SE, Lutz TB, Montione R. Thinning of the anterior capsule associated with congenital aniridia. J Cataract Refract Surg. 2003 Mar;29(3):523-5. doi: 10.1016/s0886-3350(02)01602-4. PMID: 12663018). ICG would be a better choice in congential aniridia.

    2) While peripheral “punch outs” were taught in some early experiences, there are zero reported cases in the world literature of acute angle closure from a properly placed iris device (without punch outs), nor in the hundreds of cases in the FDA study. (Ayres BD, Fant BS, Landis ZC, Miller KM, Stulting RD, Cionni RJ, Fram NR, Hamilton S, Hardten DR, Koch DD, Masket S, Price FW Jr, Rosenthal KJ, Hamill MB, Snyder ME. Results of the United States Food and Drug Administration Clinical Trial of the CustomFlex Artificial Iris. Ophthalmology. 2022 Jun;129(6):614-625. doi: 10.1016/j.ophtha.2022.01.029. Epub 2022 Feb 5. PMID: 35131359.) More importantly, the 6 punch-outs seen create necessarily creates 24 sharp points (Snyder ME, Leone AR, Werner L, Bundogji N, Hawn V. Microscopic analysis of preinsertion cutting modalities on custom, flexible iris prostheses. J Cataract Refract Surg. 2024 Feb 1;50(2):181-186. doi: 10.1097/j.jcrs.0000000000001346. PMID: 37853580) which are directly in contact to the ciliary body and can result in UGH syndrome. The punch-out are neither necessary, helpful nor risk free.

    3) Trephination of a “with fiber” version of the device creates numerous very sharp shards in the cut edge; see the terrifying SEM images: Snyder ME, Leone AR, Werner L, Bundogji N, Hawn V. Microscopic analysis of preinsertion cutting modalities on custom, flexible iris prostheses. J Cataract Refract Surg. 2024 Feb 1;50(2):181-186. doi: 10.1097/j.jcrs.0000000000001346. PMID: 37853580.

    4) When a capsular bag is intact and exists, any anterior segment hardware, including the artificial iris, is more safely placed within the confines of the capsular bag.

    5) With passive sulcus fixation of an artificial iris with no peripheral residual iris tissue tis problematic since there is nothing to prevent the peripheral aspects of the device from contacting the corneal endothelium, which can hasten endothelial decline. If sulcus fixation is required, especially when no peripheral iris remnant is present, suture fixation in that setting would be wiser.

    6) Aniridia fibrosis syndrome, a condition uinique to congenital aniridia, is a sight and eye-threatening condition with fibrosis emanating from the vestigial iris root can occur is roughly 4+% of eyes. (Tsai JH, Freeman JM, Chan CC, Schwartz GS, Derby EA, Petersen MR, Holland EJ. A progressive anterior fibrosis syndrome in patients with postsurgical congenital aniridia. Am J Ophthalmol. 2005 Dec;140(6):1075-9. doi: 10.1016/j.ajo.2005.07.035. PMID: 16376654.) Having sharp corners rubbing the uvea exactly in this location seems almost taunting.

    Feel free to put it on Kera-net if you think it would be useful.

    Best,

    M

    Michael E. Snyder, MD
    Board of Governors, Cincinnati Eye Institute
    Co-Chair, Medical Executive Board Research Committee, EyeCare Partners
    Professor of Ophthalmology, University of Cincinnati School of Medicine

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