Mitchell A Jackson MD Founder/Director, Jacksoneye Lake Villa, IL USA Aspheric Balanced Curve (ABC) IOL Technology: An Enhanced Aspheric Effect with Better Clinical Outcomes Mitchell A Jackson MD Founder/Director, Jacksoneye Lake Villa, IL USA Dr. Jackson is a consultant for Hoya Surgical
Coma Asymmetry mistake If light rays refract slant on a optical surface, you will get a deformation as illustrated Coma
Spherical aberration Aperture error Abaxial rays outside of the „Gaußschen territory“ (approx. 5°around the axis) will be refracted stronger optical axis „Gauß territory“
Influence of Aspheric IOL spherical IOL Good DOF Worse visual Quality ++ + +++ negative SA IOL ++ - - 00 - Worse DOF - Best Image Quality
Spherical aberration & IOLs aberration-free negative SA SA = + SA = 0 SA = - +20.4 +20.0 +18.0 +20.0 +20.0 +20.0 +20.4 +20.0 +18.0 Power increases from center to edge Power is uniform for all areas Power decreases from center to edge (B&L, Acritec,Lenstec) (Alcon, AMO,Acritec,HOYA)
Clear image different between both lenses with large pupil Effect of pupil size on Image Quality is mainly significant with large pupils spherical aspheric Clear image different between both lenses with large pupil
Angle Kappa 0.36mm ± 0.22 Visual Axis Angle Kappa (2o to 5o) Uday Devgan, MD devgan@ucla.edu Angle Kappa (2o to 5o) Pupillary Axis Visual Axis Fovea Angle Kappa 0.36mm ± 0.22 Average of 18 studies This slide is © Uday Devgan, MD Mean displacement between foveal axis and center of pupil of 0.37mm + 0.24mm Rynders M, Lidkea B, Chisolm W, Thibos LN. J Opt Soc Am A 1995; 12:2348-2357.
Devices can measure both pupil size & angle kappa: Hoya iTrace and Marco OPDIII examples Angle kappa = 0.72 mm Angle kappa = 0.62 mm
Power distributions (+20.0 D) Hoya “Super-prolate” effect Spherical IOL Negative SA IOL HOYA Modified 1 2 3 17 18 19 20 21 Lens Radial Distance (mm) Power (D) ABC=Aspheric Balanced Curve - design
Effect of Decentration on Contrast Optimum settings for a standard aspheric IOL (under the condition of Z40 = 0.27) Hoya’s original settings 1 0.8 0.6 Contrast Contrast 0.4 0.2 Spheric Aspheric Aperture 4.0 mm HOYA Spatial freq 50 c/mm 0.2 0.4 0.6 Decentration (mm) Decentration (mm) Hoya aspheric has better contrast, compared with a standard aspheric. Even at 0.5mm decentration, Hoya aspheric has better contrast than a spherical IOL.
Higher-Order aberrations 0.35 preoperative postoperative FY-60AD (aspheric IOL) 0.30 Pupil size: 5mm 0.25 0.20 (RMS µm) 0.15 p<0.005 p<0.05 n.s. 0.10 0.05 0.00 Spherical aberration Vertical coma Horizontal coma
Aspheric Balance Curve (ABC) IOL Technology Image Quality is the key to patient satisfaction Coma & Spherical Aberration are the bad guys Pupil size is not the only culprit Beware of angle kappa (especially over 0.4 mm) Angle kappa helpful in selecting which aspheric IOL Hoya AF-1 “super-prolate” enhanced effect is especially advantageous in high angle kappa cases >0.4 mm Angle kappa measurements may also be helpful in determining multifocal vs accommodating IOL selection