Eyeworld

45 EW CORNEA November 2016 by Mitchell Gossman, MD The purpose of the iridotomy is to prevent pupillary block caused by the air bubble (either on the table or after discharge) resulting in angle closure. The danger may vary de- pending on anterior chamber depth, pupil size, and presence of floppy iris, if any. I personally do not place an iridotomy for a standard case, in- stead ensuring that the final bubble is unlikely to cause pupillary block, i.e., approximately the same diam- eter as the donor tissue, when the patient leaves the OR, and I use a I expected the opposite majority response. Soon after trying the Busin glide, I had one case where there was a bit of doubt in my mind on the orientation of the graft despite constant surveillance. Thankfully it was correct, but I explored the best way of marking graft orientation and came to the conclusion that the best way was to have the graft marked by the eye bank while still in the artificial anterior chamber. One concern is graft toxicity from the dye, but it is a very light, small, peripheral mark and I have noted no significant issues, and seeing the correct orientation is reassuring. I imagine it would be even more so when using folding forceps and commercial folding devices. Perhaps those are less needed when using methods where the graft is pulled or pushed into the eye on a Sheets glide. The thirteenth question was, "Do you perform an iridotomy, be it YAG at the office or in the OR?" Final installment of a three-part series exploring the methods practicing ophthalmologists use when performing a DSAEK T his article, the last in a three-part series, further explores what methods are being used by practicing ophthalmologists in per- forming DSAEK surgery. A survey was performed of 12 ophthalmologists who volunteered to participate from the ranks of participants in the ASCRS EyeConnect (formerly eyeCONNECTIONS) online com- munity and volunteers in North America. Responses are anonymous in order to encourage candor. The first part of this series, in the August 2016 issue of EyeWorld, included the first five survey ques- tions, covering the topics of anes- thesia preference, incision size, and removing Descemet's. The second part, in the October 2016 issue of EyeWorld, included the next five survey questions, covering the topics of diameter graft sizes, methods for inserting the donor lenticule, suturing, and combining or staging cataract surgery and DSAEK. The eleventh question in the survey was, "What viscoelastic do you use for Descemet's removal?" Comparison of methods of performing DSAEK Pulse of ophthalmology: Survey of clinical practices and opinion Healon (Abbott Medical Optics) 50% Provisc (Alcon) 17% Balanced salt solution 17% Air 8% Z-Hyalin (Carl Zeiss Meditec) 8% Cohesive viscoelastic properties encourage fast, easy, and complete removal of viscoelastic after Descem- et's removal so as to not be a barrier to graft attachment. The twelfth question was, "Do you make, or have the eye bank make, an orientation mark on the stromal surface of the graft?" Yes 75% No 25% No 75% Yes 25% Before 73% After 27% long-acting cycloplegic (cyclopento- late) at the end of the case. For cases where I feel a PI is beneficial, I place it with the YAG laser in the office in order to avoid issues with bleeding with the scissors or vitrector meth- ods. If the need arises to make one on the table, I make an inferior PI with scissors from MicroSurgical Technologies (Redmond, Washing- ton). The fourteenth question was, "Do you suture your incision before or after instilling air?" The sixteenth question was, "Do you squeegee the corneal surface to encourage adhesion of the graft?" Under 10 minutes 17% 10–20 minutes 67% One respondent specified 30–60 minutes, probably referring to time outside the operating room As with most issues, there is a trade-off. Placing the suture prior to air instillation can be a challenge with chamber shallowing, and the potential time for the graft attach- ing while attending to the incision is lost. On the other hand, placing the suture after air instillation can be troublesome as there may be a proclivity for air to burp out of the incision. I take an intermediate approach. I place what Richard Schulze, MD, Schulze Eye, Savan- nah, Georgia, aptly describes as a small "pilot bubble" under the graft initially to elevate it into the desired location, but not under particularly high pressure or excessively large, to allow placement of sutures with reasonable eye pressurization, the graft in place for attaching, without as much tendency for air to burp out. Once the suture is placed, a higher volume and pressure bubble is placed. The fifteenth question was, "How long do you leave your bubble under high pressure prior to decom- pressing to physiologic pressure?" This was an open-ended question so I organized the responses as follows: Mitchell Gossman, MD Fluid in the space between the host and donor might prevent adhesion and result in subsequent graft dislocation. A massaging ("squeegee") maneuver starting from the center of the cornea outward on the epithelial surface may help remove fluid to promote adhesion. I do squeegee, but normally no more than one or two strokes in four to six directions, unless there are clues there is fluid present such as bubbles or striae, so as to not unnecessarily traumatize the possibly already ten- uous epithelium. The seventeenth question was, "How long do you require the pa- tient to remain supine after surgery prior to leaving the surgery center?" Supine position gazing at the ceiling provides a period of guaran- teed air bubble pressure on the graft endothelium to promote adhesion before sending the patient home where compliance may be in doubt. I require an hour at the surgery cen- ter, and ask the patient to remain su- pine and gaze at the ceiling, except as necessary, for the first 2 days. This concludes the series on DSAEK methods employed by prac- ticing ophthalmologists. I hope this has been helpful for you in explor- ing alternatives or validating your own current procedures. EW Editors' note: Dr. Gossman is in private clinical practice at Eye Surgeons & Physicians, St. Cloud, Minnesota. He has no financial interests related to this article. Contact information Gossman: n1149x@gmail.com Yes 67% No 33%

• Blank Page
• Blank Page (1)