Feasibility of multifocal intra-ocular lens exchange and conversion to the bag-in-the-lens implantation

Abstract. Purpose: Our purpose was to evaluate the surgical outcome after intra-ocular lens exchange in patients who presented impairing visual complaints after primary multifocal intra-ocular lens (MIOL) implantation. In particular, the study was undertaken to look at the number of eyes that could be equipped with the bag-in-the-lens (BIL) IOL after MIOL exchange. Methods: This series consisted of 30 eyes of 21 consecutive patients scheduled for MIOL exchange. In 15 out of the 30 eyes, IOL misalignment was measured on slit lamp anterior segment photo's after defining the mathematical centres of the IOL optic, pupil and limbus. Results: Diffractive MIOL was more frequently explanted (25; 83%) when compared with refractive MIOL (4; 13%) and progressive optic IOL (1; 4%). In 21 out of the 30 eyes (70%) a bag-in-the-lens could be implanted. In 7 out of the 30 eyes (23%), the capsule was not considered sufficiently stable to accommodate an IOL. An iris-fixated IOL or a sulcus-fixated IOL was then implanted. In 2 out of the 30 eyes (6%) the remaining capsular bag could accommodate a traditional lens-in-the-bag only. Eyes that underwent Nd:YAG laser capsulotomy prior to the MIOL exchange needed anterior vitrectomy peroperatively (11 eyes; 37%). Visual acuity improved postoperatively in 13 out of the 30 eyes and remained stable in 17 out of the 30 eyes. Conclusions: Since the BIL technique requires a very well-preserved capsular bag for the purpose of the IOL implantation, the success rate of BIL implantation after MIOL is a good indicator to evaluate the degree of difficulty to exchange MIOL.