The effects of femtosecond laser-assisted small incision lenticule extraction and phakic intraocular lens implantation on macular perfusion

Aim The aim of this study was to assess the effect of femtosecond laser-assisted small incision lenticule extraction (Femto-SMILE) and phakic intraocular lens (PIOL) implantation on macular and optic nerve perfusion utilizing optical coherence tomography angiography (OCTA). Patients and methods This is a retrospective cohort study that included 60 eyes of 60 patients having moderate to high myopia (−7.0 to −15.0 D). The patients were categorized per intervention received into: group 1 that included 26 eyes (26 patients) for whom PIOL implantation was performed and group 2 that included 34 eyes (34 patients) for whom Femto-SMILE procedure was performed. All interventions took place at the Ophthalmology Department in Alexandria Main University Hospital, Alexandria, Egypt. The study parameters (including OCTA) were assessed preoperatively, on the first day, and 2 weeks postoperatively. The OCTA parameters included macular vessel density, foveal avascular zone size, optic disc flux index, optic disc perfusion, peripapillary and macular choroidal area, macular luminal area, and macular choroidal vascularity. Results There were no statistically significant differences in the baseline characteristics between the two groups ( P >0.05). The intraocular pressure (IOP) was markedly lower in the PIOL group than in the Femto-SMILE group on the first postoperative day ( P =0.019). No other differences between the two groups were noted in terms of IOP, visual acuity, myopia, or astigmatism. There were no statistically significant differences between the two groups in macular and optic nerve perfusion, though both groups demonstrated a significant affection on the first postoperative day that was completely reversed by 2 weeks. The OCTA parameters were all comparable between the two groups both at day 1 and week 2. While certain OCTA parameters showed statistically significant differences at day 1 postoperatively, the 2-week OCTA measurements were comparable to the preoperative parameters. Conclusion Both Femto-SMILE and PIOL implantation refractive techniques demonstrated similar outcomes for macular and optic nerve perfusion. The PIOL group exhibited lower postoperative IOP on the first postoperative day.