Diffractive Trifocal Intraocular Lens Implantation in Stable Subclinical and Forme Fruste Keratoconus: A Case Series

In this retrospective case series, we examine the outcomes of diffractive trifocal intraocular lens implantation after cataract surgery, in patients with subclinical and forme fruste keratoconus. Eight eyes of four patients (aged between 47 and 64) were included in the study and underwent phacoemulsification with implantation of AT LISA tri 839MP or AT LISA tri-toric 939MP intraocular lenses (Carl Zeiss Meditec AG, Jena, Germany). Post-operative evaluation included a visual acuity test at three distances (6m, 80cm, and 40cm), a visual acuity test at three low contrast levels (25%, 12.5%, and 6%), and a questionnaire about the patients' experience with photic phenomena and overall satisfaction with the achieved quality of vision. Our results show that spectacle freedom was achieved in all cases with a high satisfaction rate among participants. We hope our results would encourage surgeons to offer this technology to carefully selected candidates with stable subclinical and forme fruste keratoconus undergoing cataract surgery, giving them the possibility of achieving spectacle independence.