Sequential/Simultaneous Phakic Intraocular Lens Exchange – Indications And Results In Short-Term Follow-Up

Phakic intraocular lens (pIOL) implantation represents the surgical procedure of choice for the management of moderate to high myopia and astigmatism (spherical equivalent above -6.0 D), providing better visual and refractive results than corneal ablation refractive treatments. A clinical advantage associated with the pIOL is its reversibility and adjustability, as it can be removed and exchanged for another model according to certain clinical indications: incorrect lens size, refractive adjustment or endothelial loss. The aim of this study is to document indications and short-term results of sequential/simultaneous phakic intraocular lens exchange.

Cornea and Anterior Segment Department, in Hospital de Braga, Braga, Portugal

A retrospective study, including all patients who underwent phakic lens explantation and simultaneous/sequential surgery to implant a new pIOL, either the same or a different model, at Braga Hospital between 2015 and 2023. The following parameters were assessed: rationale for explantation, time between surgeries, explanted and re-implanted pIOL type, corrected and uncorrected visual acuity (VA), refractive error (RE), endothelial cell density (ECD) and occurrence of intra and post-operative complications.

15 eyes/12 patients were included. Explanted pIOL were anterior and posterior chamber. 3 iris-fixated pIOL and 12 ciliary-support collamer pIOL were implanted in the posterior chamber. Rationales for explantation were the presence of residual RE (53.3%), incorrect sizing of the posterior chamber collamer pIOL (20.0%), progressive endothelial cell loss (13.3%) and pigment dispersion (6.7%). Surgery significantly improved corrected (0.1±0.28 to 0.7±0.38) and uncorrected (0.8±0.38 to 0.9±0.24) VA. All patients maintained or improved corrected VA. RE decreased significantly to 0.00±0.81D of sphere and -1.00±1.17D of cylinder. No significant decrease in ECD was found. 1 case of acute ocular hypertension occurred, resolved with medical treatment.

Changing the pIOL to a different model or dioptric power improves VA and RE. It also improves the long-term safety of this type of procedure. Changing the pIOL size improves the postoperative vault and the pIOL rotational stability. Exchanging an anterior chamber pIOL for a posterior chamber improves the long-term endothelial cell safety.