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EW RESIDENTS 52 August 2018 by Anthony Leonard, MD, PhD, Avinash Honasoge, MD, PhD, Angela Jiang, MD, Cindy Montana, MD, PhD, and Chau Pham, MD EyeWorld journal club in patients who did not undergo vitrectomy, however, this study does not break down planned versus un- planned vitrectomies. Thus, overall, this author's retinal detachment rates—despite the use of vitrectomy —appear no different than that of the general population undergo- ing phacoemulsification without planned vitrectomy. Interestingly, the rate of other complications was higher than those previously reported for uncom- plicated anterior segment surgery. For instance, the rate of vitreous hemorrhage was 38.2%. One hun- dred eight of those 131 cases with vitreous hemorrhage were associated with the placement of a scleral fixat- ed IOL or modified capsular tension ring. Review of the literature would suggest that scleral fixation portends a rate of 7% of developing vitreous hemorrhage. 10 A literature search in PubMed for "vitreous hemorrhage" and "phacoemulsification" did not yield any articles reporting the incidence of vitreous hemorrhage. In a case-control study, the odds ratio of perioperative hemorrhage in RD repair performed via pars plana limbal-based approaches employed by most anterior segment surgeons. The authors posit that theoretical- ly, the more posterior pars plana approach should lead to less traction on the retina and thus decrease the risk of retinal detachments. Compared to the incidence of retinal detachment during routine phacoemulsification, 0.39%, the authors' incidence of RD of 0.9% is higher. 7 However, taking this in con- text with the known increased risk once anterior vitrectomy is deployed (HR 27.6 in Clark et al.), it would suggest that the authors' incidence is quite a bit lower than would be expected (10.76%). 8 However, this is not a completely fair comparison given 90% of this author's cases were for a planned pars plana anteri- or vitrectomy and the extrapolation above comes from a hazard ratio derived from cases before 2001. The rate of developing retinal detach- ment following phacoemulsification with concurrent anterior vitrectomy in a more recent population-based study was 6.4. 9 In that study, overall 4-year risk of retinal detachment was 0.96% in all patients and 0.63% O ver the years, cataract sur- gery has seen an increase in outcome quality and also a decline in the inci- dence of complications. Several of these complications are associated with vitreous loss, such as endophthalmitis, cystoid macu- lar edema, retinal detachment, and corneal decompensation. According to data from Medicare and the IRIS Registry between 2010 and 2014, out of 951,968 cataract surgeries, 803 had a combined anterior vitrec- tomy procedure coded. 1 For anterior segment surgeons, the major goals of managing vitre- ous loss during cataract surgery are to remove any vitreous from the an- terior chamber and surgical wound. A literature search will show a variety of techniques described, with opinions differing between coaxial vs. bimanual instrumentation, or a limbal vs. pars plana approach. 2 The success of any technique is always first dependent on an individual sur- geon's comfort and experience, but each permutation of the vitrectomy technique carries different advantag- es and disadvantages. Disadvantages to the limbal approach include less favorable fluid dynamics, less efficient and potentially incomplete vitreous removal, and risk of further desta- bilizing the posterior capsule if the vitrectomy was performed through a PCR. 3 Disadvantages to a pars plana approach include iatrogenic retinal injury, with diagnosis and manage- ment made more difficult through a potentially edematous cornea. 4,5 Although there are no papers on the incidence rate of iatrogenic retinal injury from PPV during cataract surgery, one paper quoted a 16% incidence rate of entry-site retinal breaks during three-port PPV by vitreoretinal specialists. 6 The article by Thornton et al. is a retrospective observational series of mostly planned and a few unplanned (N=348 eyes) anterior segment vitrectromies via the 23-G single-port pars plana approach from a single surgeon. The pur- pose is to evaluate the safety and efficacy of the pars plana approach as opposed to the more common Review of "Long-term safety and efficacy vitrectomy with limbal infusion during Washington University in St. Louis ophthalmology residents Cindy Montana, MD, PhD, Avinash Honasoge, MD, PhD, and Anthony Leonard, MD, PhD Susan Culican, MD, ophthalmology residency program director, Washington University in St. Louis Whether to perform an anterior vitrectomy via a limbal or pars plana approach is controversial, and there is a paucity of published evidence. The Washington Uni- versity residents review this large retrospective study of pars plana anterior vitrectomies that appears in the July issue of JCRS. —David F. Chang, MD, EyeWorld journal club editor

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