scholarly journals The SRK regression formula in calculating the dioptric power of intraocular lenses.

1984 ◽  
Vol 68 (4) ◽  
pp. 235-237 ◽  
Author(s):  
J L Menezo ◽  
V Chaques ◽  
M Harto
Keyword(s):  
Intraocular Lenses ◽  
Regression Formula ◽  
Dioptric Power

scholarly journals Comparison of glistenings formation and their effect on forward light scatter between the Acrysof SN60WF and Eternity Natural Uni NW-60 intraocular lenses

2020 ◽  
Vol 5 (1) ◽  
pp. e000399
Author(s):  
Eva Philippaki ◽  
David P O'Brart ◽  
Chistopher C. Hull
Keyword(s):  
Image Processing ◽  
Intraocular Lenses ◽  
Accelerated Ageing ◽  
Light Scatter ◽  
Optical Bench ◽  
Median Increase ◽  
Single Piece ◽  
Dioptric Power ◽  
Processing Software ◽  
Image Processing Software

AimsTo compare the characteristics of glistenings and forward light scatter between the Alcon Acrysof SN60WF and Santen Eternity Natural Uni NW-60 intraocular lenses (IOLs).MethodsFive Acrysof SN60WF and five Eternity Natural Uni NW-60 IOLs were studied. All IOLs were single piece blue blockers with the same dioptric power (20D) and optic diameter (6.0 mm). Glistenings were induced by a thermal accelerated ageing process. Glistenings were objectively quantified using bespoke image processing software. The angular distribution of forward light scatter was measured using an optical bench system and the straylight parameter calculated from the light scatter function.ResultsThe median increase in the number of glistenings was 15 and 525 for the Eternity and Acrysof IOLs, respectively, which was statistically significantly different (p=0.012). Median glistenings diameter was 23.8 μm (Acrysof) and 32.8 μm (Eternity). Four (80%) of the Acrysof lenses had straylight values higher than a 20-year-old CIE standard glare observer and in two cases the straylight exceeded that of the 70-year-old CIE standard glare observer. None of the Eternity lenses had straylight values that exceeded the value for the 20-year-old CIE standard glare observer.ConclusionsThe Eternity Natural Uni NW-60 IOLs resisted the induction of glistenings more than the Acrysof SN60WF IOLs. Although the Acrysof IOLs developed smaller glistenings than the Eternity IOLs, there were sufficient numbers to produce a higher straylight parameter.

Combining primary and sulcus piggyback IOLs for the correction of a spherical-cylindrical defect in an eye with abnormal cornea

2021 ◽  
pp. 112067212110378
Author(s):  
Fabrizio Gaetano Saverio Franco ◽  
Cristina Nicolosi ◽  
Giulio Vicini ◽  
Piero Grasso Cannizzo ◽  
Gianni Virgili ◽  
...  
Keyword(s):  
Cataract Surgery ◽  
Intraocular Lenses ◽  
Posterior Chamber ◽  
Refractive Errors ◽  
Dioptric Power ◽  
Iol Power ◽  
Monofocal Iol ◽  
Myopic Astigmatism ◽  
Posterior Chamber Iol ◽  
High Myopic Astigmatism

Introduction: Piggyback IntraOcular Lenses (IOLs), or supplementary secondary implant lenses, have been developed to provide a sufficient dioptric power in eyes with high refractive defects, which are not fully correctable after cataract surgery with single IOL in the range of powers available. These lenses can also be used for the correction of refractive errors that occurred for a wrong choice of the IOL power after cataract surgery. Case description: We report the case of a complete refractive success obtained in a patient with an abnormal cornea, with a central stable ectasia, with thinning, high myopic astigmatism and cataract, obtained with the implant of a primary posterior chamber IOL at the time of cataract surgery and a subsequent implant of a secondary piggyback, sulcus-based customized toric IOL (Camellens FIL 622-2 Toric Monofocal IOL, Soleko, Rome, Italy). Conclusions: This brief report demonstrates the utility of combining primary and piggyback IOLs implant for the correction of a complex spherical-cylindrical refractive defect in a case of abnormal cornea and cataract.

Testing the dioptric power accuracy of exact-power-labeled intraocular lenses

2009 ◽  
Vol 35 (11) ◽  
pp. 1995-1999 ◽  
Author(s):  
Kenneth J. Hoffer ◽  
Don Calogero ◽  
Robert W. Faaland ◽  
Ilko K. Ilev
Keyword(s):  
Intraocular Lenses ◽  
Exact Power ◽  
Dioptric Power

scholarly journals Quantifying the Multiwavelength Dispersion Effect on Dioptric Power Measurement of Intraocular Lenses

2015 ◽  
Vol 7 (4) ◽  
pp. 1-7 ◽  
Author(s):  
Bennett N. Walker ◽  
Robert H. James ◽  
Don Calogero ◽  
Ilko K. Ilev
Keyword(s):  
Intraocular Lenses ◽  
Power Measurement ◽  
Dispersion Effect ◽  
Dioptric Power

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

2021 ◽  
Vol 2021 ◽  
pp. 1-5
Author(s):  
Ángel López-Vázquez ◽  
Inés Contreras ◽  
Sergio Martin-Prieto ◽  
Ángel López-Castro
Keyword(s):  
Design Methods ◽  
Intraocular Lenses ◽  
Capsular Tension Ring ◽  
Plate Design ◽  
Hydrophilic Material ◽  
Dioptric Power

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.

Sign in / Sign up

Export Citation Format

Share Document