Incision sizes with 5.5 mm total optic, 3-piece foldable intraocular lenses

PURPOSE: To determine incision sizes for 5.5 mm total optic, foldable intraocular lenses (IOLs) made of silicone or hydrophobic acrylic. SETTING: Johann Wolfgang Goethe-University, Department of Ophthalmology, Frankfurt am Main, Germany. METHODS: In a prospective randomized clinical study including 40 cataract procedures with a temporal limbal tunnel approach, incision sizes for 5.5 mm optic, 3-piece foldable IOLs were measured before and after phacoemulsification and before and after IOL implantation using calipers. Three 5.5 mm optic, 3-piece foldable IOLs were used: 2 silicone (Pharmacia CeeOn 912, Allergan SI-55NB) and 1 hydrophobic acrylic (Alcon AcrySof MA30BA). Ten lenses of each model were implanted with a forceps, and 10 SI-55NB IOLs were implanted with the AMO Unfolder injector. Measurements of the tunnel incisions at various times were statistically evaluated using an analysis of variance and the Tukey-Kramer multiple comparison test. RESULTS: Mean tunnel width before and after implantation, respectively, was 3.32 mm+/- 0.06 (SD) and 3.42+/- 0.06 mm for the CeeOn 912 using a Nichamin implantation forceps, 3.28+/- 0.09 mm and 3.42+/- 0.09 mm for the AcrySof MA30BA using a Buratto implantation forceps, 3.00+/- 0.07 mm and 3.10+/- 0.05 mm for the SI-55NB using a Fine Universal II Folder, and 2.66+/- 0.08 mm and 2.81+/- 0.11 mm for the SI-55NB using the AMO Unfolder. Incision sizes before and after implantation were statistically different between 2 IOLs (CeeOn 912 and MA30BA) and the SI-55NB groups. Implantation of the SI-55NB with the Unfolder was associated with significantly smaller incision sizes before and after implantation than implantation with the Fine folder. CONCLUSIONS: Incisions sizes of 2.8 to 3.4 mm were associated with 5.5 mm total optic, 3-piece foldable IOLs. The Allergan SI-55NB high-refractive-index silicone IOL implanted with the AMO Unfolder system provided the smallest postimplantation incision; however, the refractive optic of this IOL is 5.0 mm versus 5.5 mm for of the CeeOn 912 and AcrySof MA30BA.