Safety and efficacy of monofocal for bifocal IOL exchange and replacement

Poster Details

First Author: M.Garcia-Fernandez SPAIN

Co Author(s):    L. Fernandez Vega   J. Alfonso           

Abstract Details

Purpose:

To describe the surgical technique, to report associated problems, and to evaluate the safety and efficacy of intraocular lens exchange of monofocal for bifocal IOLs eyes with previous phacoemulsification and incorrect IOL implantation.

Setting:

Fernandez-Vega Ophthalmological Institute, Oviedo, Spain.

Methods:

Retrospective study that comprised 39 eyes of 31 patients which underwent intraocular lens exchange surgery, consisting of removal of a monofocal IOL and implantation of a diffractive IOL. All surgeries were performed between January 2005 and January 2012. The main reason for the exchange was the motivation of the patient to achieve spectacle independence for near and far vision. Other associated factors were: monofocal IOL decentration (2 cases), IOL luxation (1 case), high residual refraction (1 case), and residual lens cortex with chronic inflammation (1 case). A 4-6mm scleral incision was created, along with three side ports for assistance. The new IOL was implanted in the bag or in sulcus, depending on the integrity of the posterior capsule. In order to achieve emmetropia, refractive laser surgery (LASIK) was associated in 12 eyes. We analyzed the following parameters: uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), near visual acuity with far correction, spherical equivalent (SE) and keratometric astigmatism (KA).

Results:

Mean age of patients was 51.90±10.89 years. Mean interval between first surgery and lens exchange was 39.48±40.50 months. 32 out of 39 eyes had a monofocal IOL implanted in capsular bag and 7 in ciliar sulcus. 26 out of 32 eyes that had the IOL in capsular bag, underwent implantation of the new IOL in the bag, and 6 out of 32 eyes, in sulcus. The 7 eyes which had previously the IOL implanted in sulcus, underwent implantation of the new IOL in sulcus. UDVA (logMAR) increased from 0.51±0.358 preoperatively to 0.18±0.18 after surgery, this being statistically significant (p<0.05). Mean CDVA (logMAR) was 0.19±0.22 preoperatively and 0.16±0.18 postoperatively (p>0.05). Postoperative mean near visual acuity with far correction (logMAR) was 0.15±0.18. Safety index was 1.04±0.02. Preoperative and postoperative spherical equivalent were -0.28±1.82 D and -0.16±0.32 D, respectively (p>0.05). Regarding Kav, K2 decreased from 43.55±2.54 to 42.78±2.55 D (p<0.05), and k1 from 42.49±2.22 to 41.89±2.54 D (p<0.05). No intraoperative complications were found, although it was necessary to perform anterior vitrectomy in two eyes with previous posterior capsule rupture. Small decentration of a diffractive IOL was found postoperatively. No complications related to the refractive laser surgery were recorded.

Conclusions:

Intraocular lens exchange of a monofocal IOL for a diffractive IOL, aimed to reach spectacle independence for near and far vision, may be considered a safe and effective procedure. Moreover, solving problems associated with monofocal IOL implantation such as luxation or decentration can be an added indication to perform this surgery. FINANCIAL DISCLOSURE?: No