Primary femtosecond laser posterior capsulotomy: Without clinical outcomes, caution should be exercised

Abstract

Our group was impressed by Haeussler-Sinangin et al.’s article1 but believe it is appropriate to offer an alternative perspective regarding the consequences of immediate intended capsulotomy during cataract and intraocular lens (IOL) implantation surgery (primary femtosecond laser posterior capsulotomy). Our group remains curious about the surgical details of primary femtosecond laser posterior capsulotomy. We assume that the capsulotomy was performed after eye docking, at the conclusion of surgery, demanding a certain intraocular pressure. However, it is unclear from the paper what the energy levels required and the capsulorhexis diameter were. Given that the authors have previously described 3 primary femtosecond laser posterior capsulotomy techniques,2 our group wishes to clarify which technique was used. The authors have previously noted that smaller neodymium:YAG (Nd:YAG) laser posterior capsulotomies might minimize the dislocation rate of IOLs via the capsulotomy into the vitreous cavity.3 Given that the normal pupil is physiologically displaced inferonasally, a laser posterior capsulotomy created centrally intraoperatively might not clear the visual axis. We suspect that minimizing the risk for IOL dislocation while preventing the need for a postoperative Nd:YAG laser posterior capsulotomy mandates careful sizing and siting of the primary femtosecond laser posterior capsulotomy. If the posterior capsule disk is liberated successfully, we would like to know how it is removed from the posterior segment. Indeed, we wonder whether some patients might require laser vitreolysis or a definitive pars plana vitrectomy (PPV) to treat the persistent symptomatic floaters thereby engendered. Femtosecond laser–assisted cataract surgery has increased operative complications. A recent femtosecond laser–assisted cataract surgery study (N = 1600)4 reported increased anterior capsule tears and tags as well as IOL dislocations. There are no extant data to describe the incidence or consequences of posterior capsule tears or tags in primary femtosecond laser posterior capsulotomy. Many phacoemulsification procedures might not require laser posterior capsulotomies. In 1995, our group reported that only 1.4% of 210 phacoemulsification surgeries required Nd:YAG laser posterior capsulotomy by 14 months.5 With advances in surgical techniques, the requirement for laser posterior capsulotomy should have diminished. The authors must state whether they are performing a relatively invasive procedure intraoperatively (primary femtosecond laser posterior capsulotomy) to assist the estimated 1.0% of patients who might need it one day. Postsurgical visual outcomes are important and quantifiable. Readers have to know whether primary femtosecond laser posterior capsulotomy improves corrected distance visual acuity outcomes. The authors are to be congratulated on measuring Berger space during primary femtosecond laser posterior capsulotomy. However, possible complications from repeated docking procedures onto an incised and potentially patulous globe and the attempt to create robust pupil alignment of the capsulotomy given the accepted mesopic pupil size are concerning. We wonder whether any anterior chambers were flattened, with resultant IOL–corneal touch, during docking. Creating a nonanatomic pathway between the anterior and posterior segments in the immediate postoperative course of primary femtosecond laser posterior capsulotomy after otherwise uneventful femtosecond laser–assisted cataract surgery might increase the possibility of endophthalmitis or cystoid macular edema after cataract surgery. Given the possible present and future adverse events in relation to patient outcomes, we eagerly await the authors’ response.