BunnyLens AF - Hanita Lenses

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Page 6 of 22b. Spherical aberration:The spherical aberration is a well known phenomenon in the optic field. The sphericalaberration occurs when rays of light that pass through different parts of the lens intersect atdifferent points on the optical axis of the lens (Figure 3). Due to this aberration, a dotprojected on the retina produces a larger circle, thus inducing low quality optics, an unclearvision and low contrast (Figure 4).Figure 3:Spherical AberrationFigure 4:A demonstration of the blur caused by spherical aberration with awider pupil. The rays that enter the retina from far scatter differentlyand are projected blurredly to the retina, causing a law quality image.Contributors to spherical aberration (SA) in the eye are the cornea (average +0.27 m) andthe crystalline lens (negative in the young eye). Cataract surgery removes the lens componentand leaves positive SA on average. Traditional intraocular lenses (IOLs) are spherical withpositive SA, further increasing the SA of the pseudophakic eye.c. Clinical demand:As it gets darker and the pupil dilates, the spherical aberration becomes more apparent, andstarts to be noticeable by the patient. Thus patients with conventional spherical lensescomplain of unclear vision and poor contrast in the mesopic and scotopic conditions.d. Lens Design:There are three options to optimize lens surface:1) Aberration free lens- all aberrations of the eye remain.2) Reduce spherical aberration to zero (theoretically for 6mm pupils).3) Optimize the lens surface to achieve best functional visual acuity.The BunnyLens AF was designed using the third option: obtaining maximum ContrastSensitivity by optimizing the Modulated Transfer Function using Arizona eye model designedto match clinical levels of aberration, both on and off axis (the model is based on Navarro eyemodel and the Koojiman model and uses eye modeled for a 60 year old patient).The BunnyLens AF optical design was performed using the symmetric aspheric surfaceequation described below.Hanita Lenses Intraocular & Contact Lensesעדשות חניתהעדשות מגע ועדשות השתלה תוך-עינית•קיבוץ חניתה • 88222 www.hanitalenses.com Kibbutz Hanita 22885 Israel • Tel. 972-4-9950 700• Fax: 972-4-9950 755 •
Page 7 of 22C = 1/R: R – Radius of curvature.K- Conic ConstantR – Radial distance from optical axis.The theoretical asphericity value of BunnyLens AF for 6mm pupil opening was calculatedusing ZEMAX simulation: IOL asphericity: -0.14µm Total Spherical Aberration of an eye: +0.13µmThis pupil opening was used to compare BunnyLens AF with other aspheric IOLs available inthe market.Table 1 – Spherical aberrations for different aspheric IOLs, 6mm pupil opening:LensIOLasphericity[µm]Total sphericaberration[µm]Spheric IOL +0.18 +0.45AMO Tecnis -0.27 0Alcon IQ -0.2 +0.07ReStore aspheric -0.1 +0.17Staar Afinity -0.02 +0.25B&L sofport AO 0 +0.27BunnyLens AF -0.14 +0.13The key concept of the design was the definition of the way the eye perceives shapes underthe various conditions of contrast and luminance. The underlying principles of the concept arethe analysis of contrast vision and the MTF – The Modulated Transform Function.Optimizations of these parameters lead to the BunnyLens AF Visual Acuity improvement.In order to confirm accurate perception of image quality by the new designed optics, theBunnyLens AF optic design relies on the MTF (Modulation Transfer Function), the best toolfor objective quantitative measurement of visual performance and contrast sensitivity.The MTF is also an extremely sensitive measure of image quality degeneration, enabling anaccurate evaluation of the aberration degree.The BunnyLens AF exceed the standard spherical intraocular lenses, ensuring improvedquality of image and high contrast sight sensitivity for a higher range of spatial frequencies.This advantage is kept even at difficult visual situations, such as low light conditions withenlarged pupils, or decentration of the lens. The reduction and control of spherical aberrationsresults in superior vision quality for pseudophakic patients, by providing the best imagequality the retina can interpret.Hanita Lenses Intraocular & Contact Lensesעדשות חניתהעדשות מגע ועדשות השתלה תוך-עינית•קיבוץ חניתה • 88222 www.hanitalenses.com Kibbutz Hanita 22885 Israel • Tel. 972-4-9950 700• Fax: 972-4-9950 755 •
Page 1: עדשות חניתהHanita LensesC
Page 5: Page 5 of 22Figure 1: BunnyLens AF
Page 9 and 10: Page 9 of 22Figure 7: The influence
Page 11 and 12: Page 11 of 22Results:a. IOL perform
Page 13 and 14: Page 13 of 22Graph 3: 3-month Post-
Page 17 and 18: Page 17 of 22f. Intra-operative com
Page 19 and 20: Page 19 of 22i. Clinical Evaluation
Page 21 and 22: Page 21 of 22Conclusions:All surgeo

BunnyLens AF - Hanita Lenses

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