EFCLIN 2018

‘IOLs for Better or Worse’

Consultant :Santen/AVSAnewOptic IncOptical ExpressOcular Therapeutix

Previously :AlconNovartisB and LZeissOculentis

St Thomas’ Hospital 1871

1868

1946

‘Why don’t you put a new lens in the eye, Sir ? ’

The story of how the first IOL happened is well known

Ridley’s observation that Perspex did not cause a foreign body reaction

The first operation

The first IOL operation was a secondary implant

• Overlooked in the furore that followed

• Extremely fortuitous

• By 3 months the capsule would have thickened and supported the IOL leading to an anatomical success

Posterior Capsule Opacification

63.8%

In 1994 Alcon approached me to see if we could confirm the German observation -

we started a study of PCO in PMMA, Silicone and Acrysof IOLs

Silicone PMMA Acrysof

0

10

20

30

40

50

60

6m 1yr 2yr 3yr

PMMASiliconeAcrysof

Percentage PCO vs Time

P=0.0001

Hollick Ophthal 1998

Dr O Nishi showed that a square edge profile prevented PCO

O Nishi et al JCRS 1999

Bag collapses around

the IOL and the posterior edge

creates a pressure

barrier to LEC migration

AcrySof SN60 Hoya YA-60BB(now obsolete)

Single piece hydrophobic acrylic, 6mm optic

Both marketed as square edge IOLs

0

20

40

60

80

100

3m 6m 12m 18m 24m

AcrysofHoya

Area of PCO

Median%

PCO

**

**

*

* P= <0.5

Hancox JCRS 2008

59 24227 192

395 360

745 710

Hoya Acrysof

PCO• Not all ‘square edges’ are equal• Hydrophilic IOLs are not so good

19.9µ - bad9.3µ - good

Acrysof Hoya

Silicone IOLs

Bausch & Lomb Soflex SE Bausch & Lomb SofPort AO

8.3µ 7.6µ

Hydrophobic Acrylic IOLs

Alcon

AcrySof IQ

Alcon

AcrySof Natural

Alcon

AcrySof MA60AC

8.5µ 9.3µ 9.9µ

AMO

Sensar

AMO

Tecnis Z9000

AMO

Tecnis ZM9000

9.2µ 9.0µ8.3µ

Hydrophilic IOLs get more PCO

Hydrophilic Acrylic IOLs

Bausch & Lomb Akreos

15.9µ

LenstecTetraflex

23.1µ

Rayner Superflex

15.6µ

• Machined dehydrated• Tumble polished to remove burr• Edge profile lost

• Inter relationship between material and engineering

What is a ‘square edge’ ?What is the best edge profile ??

The Lens that failed

Dreadful PCO

…. re engineer for 1.8mm incisionImprove edge and PCO prevention

B and L MI60MICS IOL

Accuject 2.2

Viscoject 1.8

Viscoject

1.5mm Internal diameter

MI60

• Specific injection system

• Material : resist higher compression forces, controlled unfolding

• Design : perfect stability in the bag, prevent PCO, provide excellent optical properties

Challenges

• Same hydrophilic and hydrophobic polymers but more PMMA and less water

• This makes the polymer stiffer and more resistant to tearingAkreos IOL Material

Hydrophilic HEMA

Hydrophobic PMMA

Water

INCISE IOL Material

31

Material Solution .... new custom designed polymer

• Reduced water content compared 22% versus 26%

Tensile strength

-Extremely resistant material-Tear strength : +300%

-Allows strong compression forces-Avoid haptic break during injection

Akreos

Modulus (rigidity)

-Stiffer than Akreos even at body temperature (35°C)-More stable in the capsular bag-More stable if bag compression Akreos

Elongation

-Strongly improved compared to Akreos (+43%)-Allows injection through very small cartridges

Akreos

Sharpest 360° Barrier Edge• New sharp edge process on the 360° posterior barrier

16µm

Akreos1 5µm

5µm

INCISE2

“It has a much better profile than previous hydrophilic IOLsand has the best edge of any IOL we have ever imaged”*

Prof. David Spalton2

1. Nanavaty MA et al. J Cataract Refract Surg 2008;34:677–686.2. Imaging & Evaluation of 1.4 IOL St Thomas’ Hospital Anish Dhital, David Spalton, Jimmy Boyce.. 35

*As imaged by David Spalton

High incidence of decentration - haptics too thin ?? ---- abandoned

• Hydrophilic IOL calcification – a problem solved

• A lens that died

• A new EDOF concept

• Accommodation – a lens for the future

Santen ‘Easy Focus’ IOL

A new ‘EDOF’ IOL

Consultant to Santen AVS

Trifocals

Better near vision

EDOF

Less dysphotopsia

Design Concept of the xact Mono-EDoF ME4

Visual Range“Depth of Focus”

Mono-FocalIOL

Bifocal+4D

EDoF+1.5D

Trifocal

NearDistance

IntermediateDistance

FarDistance

Minimal optical side effects

Halo /Glare/ Double vision

Reduced Halo / Glare

Xact MonoEDoF

Applicable to wider range of

patients

Aim of the project

• Hydrophobic diffractive IOLwith 4 rings

Lens performance through

• optical bench testing, • real life simulation• clinical evaluation

To produce a novel and different EDOF IOL

Lens type Optics Example

Monofocal Refractive Santen Xact W-60R

EDoF Diffractive Tecnis SymfonyZeiss At Lara

Aberration based Sifi Miniwell

Diffractive Santen Xact Mono-EDoF ME4

IOLs tested

Optical Bench Testing

• Optical Test Equipment : Trioptics OptoSpheric bench

• Model Cornea Used : Corneas matched to IOL asphericity

• Pupil Sizes (at the IOL plane) : 3.0 mm & 4.5 mm

• 550nm wavelength per ISO requirement

• Spatial frequency measured at 15 (50 lp) and 30 cycles / degree (100 lp) per equivalent to 20/40 and 20/20 (per ISO requirement)

Through Focus MTF Curves

Santen Mono-EDoF IOL has a broad single peak

Other EDoF IOLs have a biphasic curve which are smoothed by white light and corneal aberrations

Optical Bench Testing

Through Focus Images : 3mm aperture with Corneal asphericity matched to IOL asphericity

Monofocal(W-60R)

Mono-EDoF

Symfony

Miniwell

AT LARA

-0.5D 0.0D 0.5D 1.0D 1.5D

• Mono-EDoF has crisp emmetropic focus

• Excellent image quality from distance to immediate focus

4.5 mm pupil

3.0 mm pupilAverage MTF at

100lp/mm (20/20) for 60-70

yrs old

Effect of pupil size on MTF

Impact of Tilt and Decentration on MTF at 4.5mm pupil

0.5mm decentration

5° TiltMono-EDoF performs as well as normal eyeand is relatively insensitive to decentration and tilt

Average MTF at 50 lp/mm (20/40) eyes between 60 and 70 years old

• Mono-EDoF has a significantly higher MTF than the average MTF of an age matched phakic eye

• Mono-EDoF has higher MTF than other EDoFIOLs

• Relatively resistant to decentration and tilt in comparison to competitor IOLs

Optical bench testing

Real Life Vision Simulation Testing

• 3 cameras mounted side by side on car dashboard looking at the same object

• Wet cell system with matching corneas

• Images recorded under identical camera settings

Polychromatic Images / Photopic Conditions

Monofocal Mono-EDoF Tecnis Symfony

Distance

Decentered by 0.5mm

Polychromatic Images with Decentration / Mesopic Conditions

Monofocal Mono-EDoF Tecnis Symfony

View of car headlights with IOL off-axis (decentered by 0.5mm)

HeadlightsOff

HeadlightsOn

Video recording of car headlights with model cornea

Monofocal Mono-EDoF Tecnis Symfony

Night time conditions – 4.5mm at the IOL plane

Clinical Testing

• Pilot study – Florian Kretz, Rheine, Germany

• Healthy, normal eyes except for cataract– Preoperative keratometric cylinder ≤ 1.0 D

• Three month data– 4 patients, 8 eyes

1.5 D

3 month post-op Defocus Curve: xact Mono-EDoF

~ 1.80 D

~ 1.5D of Depth of Focus Monocular testing

~ 1.8D of Depth of Focus Binocular testing

Photopic contrast sensitivity

4 patients, 8 eyes

3 month post-op

There is no statistically significant differences between contrast sensitivity measurements with and without glare

Mesopic Contrast sensitivity

VISUAL EFFECTS ASSESSMENT

There were no complaints of unwanted visual effects.

Conclusion

• Higher MTF values and continuous range of vision is expected to result in higher levels of patient satisfaction

• Only 4 rings --- Low incidence of dysphoticsymptoms

Conclusion• Constant improvement in IOLs

• No such thing as a perfect IOL