Customized IOLsCustomized IOLs--Post InsertionPost InsertionChristian A. Sandstedt, Ph.D.Christian A. Sandstedt, Ph.D.

Calhoun Vision, IncCalhoun Vision, IncPasadena, CAPasadena, CA

44thth International Conference of International Conference of Wavefront Sensing and Wavefront Sensing and

AberrationAberration--Free Refractive Free Refractive CorrectionCorrection

San Francisco, CASan Francisco, CAFebruary 15, 2003February 15, 2003

The Light Adjustable Lens (LAL)

The Light Adjustable Lens The Light Adjustable Lens (LAL)(LAL)

Clinical need and background

Description of technology

In-vitro testing and results

Examples and future work on higher order aberration correction

Clinical need and backgroundClinical need and background

Description of technologyDescription of technology

InIn--vitrovitro testing and resultstesting and results

Examples and future work on higher Examples and future work on higher order aberration correctionorder aberration correction

• Cataract surgery with IOL implantation is the most commonly performed surgery in patients over 65

• 50% of these patients require spectacle correction after insertion and refractive stabilization

Defocus, Lateral Displacement, Post-Operative Astigmatism (Unpredictable Wound Healing), Rotation.

• 98% of these are within ± 2 D.

• Cataract surgery with IOL implantation is the most commonly performed surgery in patients over 65

• 50% of these patients require spectacle correction after insertion and refractive stabilization

Defocus, Lateral Displacement, Post-Operative Astigmatism (Unpredictable Wound Healing), Rotation.

• 98% of these are within ± 2 D.

Clinical NeedClinical NeedClinical Need

Non-Invasive Alteration of IOL Power Post-OperativelyNonNon--Invasive Alteration of Invasive Alteration of

IOL Power PostIOL Power Post--OperativelyOperativelyFoldable IOL made of photosensitive material

Adjust IOL power post-operatively by treating with safe levels of light to alter its refractive properties

Foldable IOL made of photosensitive materialFoldable IOL made of photosensitive material

Adjust IOL power postAdjust IOL power post--operatively by treating operatively by treating with safe levels of light to alter its refractive with safe levels of light to alter its refractive propertiesproperties

Animation: Hyperopic Correction

Animation: Hyperopic Animation: Hyperopic CorrectionCorrection

Single Pass InterferometrySingle Pass Interferometry

Myopic CorrectionMyopic CorrectionMyopic Correction

Measurements made in double passThe number of interference fringes (OPD) proportional to the induced power change

Measurements made in double passMeasurements made in double passThe number of interference fringes (OPD) proportional to The number of interference fringes (OPD) proportional to the induced power changethe induced power change

Pre-irradiation +20 D LAL –2 D Correction

Sample In Vitro NomogramSample In Vitro NomogramSample In Vitro Nomogram

The intensity is kept constant and the time is varied The intensity is kept constant and the time is varied The intensity is kept constant and the time is varied

-2.0

-1.5

-1.0

-0.5

0.00 1 2 3 4 5 6 7 8 9

Dose #

∆D

iopt

ers

Method of LAL Optical Characterization: MTFMethod of LAL Optical Method of LAL Optical Characterization: MTFCharacterization: MTF

MTF measurements made in a wet cell with the ISO prescribed model eyeMTF of LAL comparable to commercial IOL

MTF measurements made in a wet cell with the ISO MTF measurements made in a wet cell with the ISO prescribed model eyeprescribed model eyeMTF of LAL comparable to commercial IOLMTF of LAL comparable to commercial IOL

0

0.2

0.4

0.6

0.8

1

0 50 100 150lp/mm

Mod

ulus

MTF LAL Post Lock-In

MTF Allergan Si40 IOL

MTF LAL Pre-Adjustment

MTF = 0.43 @100 lp/mm

Hyperopic CorrectionHyperopic CorrectionHyperopic Correction

Measurements made in double passThe number of interference fringes (OPD) proportional to the induced power change

Measurements made in double passMeasurements made in double passThe number of interference fringes (OPD) proportional to The number of interference fringes (OPD) proportional to the induced power changethe induced power change

Calhoun Vision LAL Preirradiation + 20.0 D

Calhoun Vision LAL + 2.0 D Correction

Future WorkFuture WorkInIn--Vitro AstigmatismVitro Astigmatism

Astigmatic Correction:3.50 D ± 0.15 Dof Toric Correction

Classic Astigmatic Wavefront

Multifocality

- Treatment of Presbyopia Without Need forAccommodation

- Embodiments- Diffractive Optics

- Refractive Optics- Central Add and Central Subtract- Repeating Zones (Allergan Array)

Calhoun CapabilitiesCalhoun Capabilities

Predictable Achievement of EmmetropiaMultifocal IOL Centered on Visual AxisCustomizable Zone SizeCenter Add and/or SubtractPotential Non Invasive Reversibility

Multifocality After Two Corrections

+2.0 D Add in Center 2 mm Zone Size

Patient with +22.5 D LAL –2.0 D Post-Op Myopic Error

Light Adjustment

In Situ Creation of MF

Removal of -0.5 D Of Power

Removal of –1.5 D Of Power

Light Adjustment

Digital Light Delivery DeviceDigital Light Delivery DeviceDigital Light Delivery DeviceBreadboard System Developed in Collaboration with Carl Zeiss-Meditech AGAllows Researcher/Physician Control of Applied Spatial Intensity Pattern

Digital Light Delivery DeviceDigital Light Delivery DeviceDigital Light Delivery Device

( ) θρ−ρ= 2cos34I 22Tetrafoil

Tetrafoil Bitmap Spatial Intensity Pattern for Input to the DMD

Digital Light Delivery DeviceDigital Light Delivery DeviceDigital Light Delivery Device- Tetrafoil Imprint

Spherical AberrationSpherical AberrationSpherical Aberration

CauseOPD between the paraxial and marginal rays

Different annular zones of a lens focus at different points along the optical axis

CauseCauseOPD between the paraxial and marginal rays OPD between the paraxial and marginal rays

Different annular zones of a lens focus at different Different annular zones of a lens focus at different points along the optical axispoints along the optical axis

Paraxial Focus

Marginal FocusBestFocus

Spherical AberrationSpherical AberrationSpherical AberrationTreatment Correction

Irradiation of an annular ring on the periphery of the LAL

Note the removal of ~2 fringes (1 Wave) of LSA

Treatment CorrectionTreatment CorrectionIrradiation of an annular ring on the periphery of the Irradiation of an annular ring on the periphery of the LALLAL

Note the removal of ~2 fringes (1 Wave) of LSA Note the removal of ~2 fringes (1 Wave) of LSA

Preirradiation 24 hours Post Irradiation

What The LAL Can DoWhat The LAL Can DoWhat The LAL Can Do

Correct spherical errors with high reproducibility and repeatibiltyMaintain optical quality through the entire treatment procedure Astigmatic correctionsCustomized BifocalityHigher order aberrations

All of these once it has been implanted in the eye!

Last SlideLast SlideLast Slide

Special Thanks

Calhoun Vision TeamDan Schwartz, MDShiao Chang, PhDJay Wilson, MSVeronica Jaramillo, PhD

Special ThanksSpecial Thanks

Calhoun Vision TeamCalhoun Vision TeamDan Schwartz, MDDan Schwartz, MDShiaoShiao Chang, PhDChang, PhDJay Wilson, MSJay Wilson, MSVeronica Jaramillo, PhDVeronica Jaramillo, PhD