Weight of Different Intraocular Lenses: Evaluation of Toricity, Focality, Design, and Material

PURPOSE: To evaluate the weight of intraocular lenses (IOLs) depending on their material, dioptric power, toricity, focality, and haptic design. METHODS: Twenty-eight different IOL models from nine different medical companies (a total of 38 IOLs) and 1 capsular tension ring (CTR) were evaluated. IOLs were weighed using a precision scale, in hydrated conditions, as an approximation to their intraocular status. RESULTS: Hydrophilic IOLs were heavier than hydrophobic lenses (p < 0.001). Regarding toricity, no statistical differences were found comparing toric to non-toric models (p=0.1). Likewise, no differences were found between multifocal IOLs and monofocal IOLs (p=0.19). Dioptric power did not affect IOL weight: IOLs of <15DP had similar weights to those of ≥15D and IOLs of ≥24D had similar weights to those of <24 D (p=0.86 and p=0.59, respectively). Plate-design IOLs were significantly heavier than 1-piece C-loop (p < 0.001), 3-piece C-loop (p < 0.001), and 4-haptic lenses (p=0.001). CONCLUSIONS: Of the characteristics analyzed that might influence IOL weight, lenses with hydrophilic material and plate-haptic design were found to be heavier. Toricity, focality, and dioptric power had no influence on IOL weight.