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50 | EYEWORLD DAILY NEWS | MAY 17, 2020 DAILY NEWS ASCRS VIRTUAL ANNUAL MEETING decompensation," she noted, referencing how this finding is in line with other studies. Dr. Imken concluded that reporting outcomes and complications with pIOL studies can provide data for establishing guidelines on risk-assessment and follow-up studies. "We believe a small an- terior chamber depth and a small lateral endothelial-lens distance could be predictors of endothelial cell loss and corneal decompensation. So, a threshold for endothelial cell loss and lateral endothe- lial-lens distance should be recommended that warrant pIOL extraction." Find these paper pre- sentations and others on keratorefractive complications in SPS-109. Editors' note: The physicians have no financial interests related to their presentations. by Liz Hillman Editorial Co-Director K eratorefractive compli- cations was the topic of presentations in a paper session. One paper by Liu Lina, MD, Chongqing, China, and Bai Ji, MD, Chongqing, China, took a look at suction loss during SMILE. Suction loss is a common complication for SMILE sur- gery, they shared, especially for those who are just beginning to use this refractive surgery option. Dr. Liu and Dr. Bai sought to analyze the influenc- ing factors for stable cones and investigate strategies to prevent this suction loss. Volunteers simulated the direction and degree of eye and head movement that could occur during the oper- ation, leading to suction loss. From there, the researchers applied corresponding inter- vention strategies to prevent this suction loss. Finally, the researchers compared the inci- dence of suction loss between a group with interventions and a control group. Watching intraoperative video of the SMILE procedure, they found most suction loss is a gradual process. Fifty eyes were observed, and in 96% of cases, suction loss, when it oc- curred, took place in the upper part (superior temporal and nasal quadrants). When vol- unteers simulated suction loss by moving their jaw down and forehead up, superior suction loss occurred. Eye movement and mandibular movement were the main causes of suc- tion loss, the study authors concluded. Their presentation shared four stages of suction loss, from minimal to significant. When suction loss is more significant and in the treatment zone, the laser scanning should be stopped, they noted. To prevent movement that could lead to suction loss, they presented that there should be communication about this between doctors and patients preoperatively and efforts should be taken to ensure head and eye stability intraopera- tively. Suction loss is common, but if we can handle it prop- erly, we can control it, the presentation concluded. A different paper presented by Fiorella Casanova Imken, MD, Lima, Peru, focused on causes for explantation of iris-fixated phakic IOLs. The retrospective, cohort, single- center study included 253 eyes of 176 patients with a pIOL (Artisan/Artiflex, Ophtec) im- planted from 2001–2019. The study compared pa- tients who did not have the lens explanted, which account- ed for 86.4% of eyes, to those who did have the lens explant- ed, which occurred in 13.8% of eyes after a mean of 12.18 years. Dr. Imken said later in her presentation that this is the first study, to their knowl- edge, to compare endothelial cell density, anterior chamber depth, and lateral endotheli- al-lens distance in eyes that did not require pIOL extraction, eyes that required explan- tation, and eyes that also required corneal transplant. Looking at preoperative characteristics, Dr. Imken said they found patients with a smaller endothelial-lens distance and smaller preop an- terior chamber depth were at higher risk for endothelial cell loss with a pIOL, a finding sim- ilar to other studies. The main cause of explantation was cat- aract formation (62.9%) and endothelial cell loss (28.6%). According to Dr. Imken, after 8 years of follow-up, the non-explanted group had a mean endothelial cell count of 2,182 (SD 438.6) and a mean decline of endothelial cell den- sity of 58.4 cells/mm 2 (or 2.2% per year). The explanted group had a mean endothelial cell count of 1,324 (SD 380) over this time and a mean loss of endothelial cell density of 157 cells/mm 2 (5.8% per year). Dr. Imken referenced sev- eral studies that showed mean endothelial cell density loss as well as one by Georges Baikoff, MD, that recommended a min- imum endothelial-lens distance of at least 1.5 mm to minimize risk of corneal decompensa- tion. "But in our study, the eyes with lateral distance of 1.41 did not have significant en- dothelial cell loss or corneal Research expands knowledge on keratorefractive complications Suction loss during SMILE was the topic of one paper presentation. Source: Liu Lina, MD, and Bai Ji, MD, screenshot from presentation

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