Multifocal IOL Basics

Transcription

1 Multifocal IOL Basics

2 Types of Multifocal Designs REFRACTIVE Concentric zones: M-flex (Rayner) Segmented: LENTIS Mplus (Oculentis) DIFFRACTIVE Progressive: 677MY (Medicontur) Bifocal: IQ AcrySof ReSTOR (Alcon) Trifocal: FineVision (PhysIOL) Extended Depth Of Focus (EDOF): Tecnis Symfony (AMO)

3 Success of Multifocal IOLs IOL Material Chromatic aberration Technology Bifocal, trifocal, progressive Customize.. Exact sizing/refraction Precision (halos, glares) Light utilisation (contrast) DESIGN - PCO protection PATIENT SELECTION Eye Anatomy (aberrations, astigmatism, kappa angle) Retina Anatomy (esp. macula) the first place /neuro-receptor of receiving signals Pupil Dynamic pupilometry Brain Neuroadaptation? Cognitive function cognitive tests? (METROVISION)

4 Neuroadaptation? Despite the fact that it is generally accepted that the brain plays a major role in visual performance with these more complex intraocular lenses, which is referred as neuroadaptation, there are no studies available evaluating cortical activity in the presence of multifocal lenses Rosa AM, BioMed Res, 2013

5 Why does it seem that neuroadaptation differs in different IOLs?

6 Role of Retina in transferring the input RETINA = 1st CONTACT - PHOTORECEPTORS Colour, depth, shape, motions = encoded by photoreceptors of few hundred microns of retinal thickness Incoming visual signals are processed by at least 80 neural cell populations and 20 separate channels within the retina Visual information leaves the retina through 20 different channels The cortex extracts the relevant information from the retinal input Visual input is initially encoded in the retina in two dimensions: light & intensity Jonathan J Nassi & Edward M. Callaway: Parallel Processing Strategies of the Primate Visual System;

7 Success of MF Neuroadaptation or IOL (design, material) The better the transfer of information from the retinal photoreceptors through the ganglion cells to the brain i.e. better output (less work for brain) the better the toleration of patients quicker neuroadaptation OPTIC is CRUCIAL = IOL

8 ZOOM ON DIFFRACTIVE OPTICAL PRINCIPLES

9 DIFRACTIVE OPTICAL PRINCIPLES Diffraction refers to various phenomena which occur when a wave encounters an obstacle. = bending of waves around small obstacles and the spreading out of waves past small openings As the waves spread out into each other, constructive and destructive interference occurs

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11 Geometric and Diffractive Optics A simple refractive lens can be described mathematically with geometric optics. The dimensions of an IOL is several orders of magnitude higher than the light wavelength. DIFFRACTION IS NEGLIBLE Due to the wave-like behaviour of the light, the more precise mathematical description is given the diffractive optics. The diffraction can not negligible if in the presence of small obstacles or slits in the light path.

12 Effect of Diffractive Elements The diffraction is increasing if the dimensions of the microstructure and the light wavelength can be found in the same order of magnitude. Theoretically, infinite diffraction order is generated. 2 nd diffractive order 1 st diffractive order 0 th diffractive order The enhanced diffractive orders can be chosen with the microstructure design. For example: Enhanced 0 th and 1 st orders provide a bifocal IOL.

13 Comparison of a Monofocal (Refractive) and a Multifocal (Diffractive) IOL Monofocal (refractive) IOL Multifocal (diffractive) IOL MTF through-focus performance: MTF through-focus performance: Distance vision Distance vision Near vision

14 Connection Between Diffractive Orders and Additional Dioptric Powers P add is designed by the diffractive structure EXAMPLE: 0 th diffractive order 0 0 D 1 st diffractive order P add 1.08 D 0 th order normally provides the far vision ( refractive focal point) 2 nd diffractive order 2 P add 2.17 D 3 rd diffractive order 3 P add 3.25 D......

15 Basic Structure of a Diffractive IOL DIFFRACTIVE ARRAY + MONOFOCAL / TORIC LENS = MULTIFOCAL / MULTIFOCAL-TORIC LENS

16 Key Parameters for Diffractive Design When dealing with a diffractive optic these must be considered: The reference wavelength is 555 nm (green): the peak of photopic sensitivity of retinal cells Reading (vision) distance is determined by the additional dioptric: Reading (vision) distance(s) ~ 1 P add Additional dioptric power [D] Reading (vision) distance [cm] Examples:

17 Diffractive Structure Characteristics STEP HEIGHT determines energy distribution between far and additional focal points

18 Diffractive Structure Characteristics STEP WIDTH determines additional dioptric power (the higher the addition the more frequented the diffractive rings)

19 Trifocal Diffractive Structure Design (FineVision) 1 st diffractive structure: P add = 3.50 D 2 nd diffractive structure: P add = 1.75 D Superimposed structure: 0 th order: FAR 1 st order: NEAR (3.5 D) 2 nd order: NOT USABLE (7.0 D) 0 th order: FAR 1 st order: INTERMEDIATE (1.75 D) 2 nd order: NEAR (3.5 D) + = 2 nd order of the 2 nd diffractive structure coincides with the 1 st order of the 1 st diffractive structure International patent ID: WO (A1) (assignee: PhysIOL)

20 Quadrofocal Diffractive Structure Design (PanOptix) Four consecutive diffractive orders: 0 th 1 st 2 nd 3 rd Corresponding dioptric powers: 0 (far) st diffractive order (+1.08 D) is suppressed US Patent ID: B2 (assignee: Novartis AG)

21 Apodization of a Diffractive Structure Before apodization Apodized structure Apodization: Decreasing steps height from the centre to the periphery

22 Effects of Apodization Pupil-dependent light intensity distribution between the far and additional focal points. Reduced light losses. Additional focal point or points are suppressed at large apertures to decrease risk of dysphotopic effects (for instance: halo).

23 Chromatic Aberration & DIFFRACTIVE OPTICs An important issue with diffractive optics is chromatic aberration. WHY?

24 Basics of Chromatic Aberration Different wavelengths are focused to different focal points Chromatic aberration is occured by the wavelength dependence of the refractive index Bi-Flex 677MY is made by Benz 25, hydrophilic acrylic material having low chromatic aberration Chromatic blur (ABBE NUMBER: 58)

25 Chromatic Aberration of a Diffractive IOL in the Human eye Far focal point: The larger wavelength, the lower dioptric power due to the positive chromatic aberration of the imaging ocular tissues. Additional focal point: Slight chromatic shift due to the opposite polychromatic characteristics of the human cornea and the wavelengthdependence of the near focus.

26 ZOOM ON..

27 Bi-Flex M diffractive refractive design concept to provide improved control energy distribution 7 diffractive discontinuities, or steps, that have been incorporated in the anterior surface of the acrylic optic to provide the diffractive added power apodized diffractive optic design apodization improves image quality by optimizing light energy delivered to the retina by distributing the appropriate amounts of light to near and distant focal points, regardless of lighting situation.

28 Biconvex Optic 13mm Anterior Apodized Optic 6 mm 6 mm Aspheric Optic (neutral approach)

29 Bi-Flex M Technology Central 3.0 mm apodized diffractive structure Step heights decrease peripherally from microns +3.5D at lens plane equalling +2.7D at spectacle plane Outer refractive zone Aspheric (neutral approach)

30 Examples for Diffractive Multifocal IOL Alcon AcrySof IQ PanOptix (non-apodized trifocal; P add = 2.17 / 3.25 D) Alcon AcrySof IQ ReSTOR (apodized bifocal; P add = 2.5 D; 3.0 D) AMO Tecnis Symfony (non-apodized EDOF; P add = 1.75 D) PhysIOL FineVision (apodized trifocal; P add = 1.75 / 3.50 D) Zeiss AT LISA tri (non-apodized trifocal; P add = 1.66 / 3.25 D)

31 Bifocal IOLs Clinical Aspects Characteristics: 1,4 1,2 Very good far vision Very good near vision Insufficient intermediate vision Dysphotopic effects (halo, glare) depends on the diameter of the diffractive optics Chromatic aberration depends on the Abbé-number (the higher the Abbé-number, the lower the chromatic aberration) 0 th and 1 st consecutive diffractive orders are used generally (reduced light loss) 1 0,8 0,6 0,4 0,2 0

32 Trifocal IOLs Clinical Aspects Characteristics: Compromised good far vision Compromised good near vision Sufficient intermediate vision Dysphotopic effects (halo, glare) depends on the diameter of the diffractive optics Chromatic aberration depends on the Abbé-number (the higher the Abbé-number, the lower the chromatic aberration) 0 th and two consecutive diffractive orders are used generally (reduced light loss)

33 ASSESSMENT OF OPTICAL QUALITY MTF means how faithfully the lens reproduces detail from the object to the image produced by the lens. Modulation Tranfer Function Transmitted contrast 100% MTF = 1 Transmitted contrast 50% MTF = 0.5 Transmitted contrast 2% MTF = 0.02

34 MTF through-focus Performance of Bi-Flex 677MY and FineVision MTF means how faithfully the lens reproduces detail from the object to the image produced by the lens Measurements performed for a spatial frequency of 50 lp/mm according to the related ISO standard

35 Progressive Apodized Diffractive (PAD) Structure on Bi-Flex 677MY Progressive apodization: Reduces light loss Reduced risk of dysphotopic effects Enhances depth of focus (PROGRESSIVE VISION within full accommodative range) Improves the distance vision at large pupil apertures

36 Bi-Flex M - Progressive IOL Normal diffractive array distance near The diffractive / progressive matrix increases the depth of field of the near vision distance vision. (b). The curves overlap in defocus the intermediate vision zone with a defocus of 1.5 dpt (67cm).

37 Bi-Flex M: PAD Characteristics: Very good (not compromised) far vision Very good near vision Competitive intermediate vision with trifocal IOLs Low level of photopic phenomena thanks very high Abbe number (58) of the material and precision of diffractive steps Quick neuroadaptation

38 Progressive Apodized Diffractive (PAD) Structure on Bi-Flex 677MY Bi-Flex 677MY Bifocal competitor Sub-micrometer manufacturing precision: reduced light loss less dysphotopic effects

39 ZOOM ON..

40 Bi-Flex M diffractive refractive design concept to provide improved control energy distribution 7 diffractive discontinuities, or steps, that have been incorporated in the anterior surface of the acrylic optic to provide the diffractive added power apodized diffractive optic design apodization improves image quality by optimizing light energy delivered to the retina by distributing the appropriate amounts of light to near and distant focal points, regardless of lighting situation.

41 Biconvex Optic 13mm Anterior Apodized Optic 6 mm 6 mm Aspheric Optic (neutral approach)

42 Bi-Flex M Technology Central 3.0 mm apodized diffractive structure Step heights decrease peripherally from microns +3.5D at lens plane equalling +2.7D at spectacle plane Outer refractive zone Aspheric (neutral approach)

43 Bi-Flex M and PCO PCO is limiting factor of success of multifocal IOLs PCO rate finally makes a difference in outcomes and patient satisfaction PCO prevention is more important for patients receiving multifocal IOLs because of their increasing visual demands Bi-Flex M r = 10microns Polish free technology

44 A unique & patented design With 180 total contact angle with capsular bag equator Experimental simulator with a diameter of 9 mm Medicontur Bi-Flex Average contact angle: 88.8 Competitor 1 Average contact Angle: 69 Competitor 2 Average contact Angle: 64.4

45 + Natural Yellow Filter for FILTERING AS MUCH AS NECESSARY for PRESERVING AS MUCH AS POSSIBLE Medicontur natural yellow filter protects the macula against the wavelengths comprised between 390nm and 460nm thus covering the whole most dangerous zone of «blue light» and maintaining scotopic vision (over 460nm) Bi Flex M yellow filter

46 + Simulation of vision without and with yellow filter IOL With NO Yellow filter MEDICONTUR Natural Yellow filter IOL With NON natural Yellow filter

47 WHAT ABOUT THE MAIN COMPETITORs?

48 Examples Trifocal, non-apodized: AT LISA tri (Zeiss): +1.67D, +3.33D Apodized bifocal: ReSTOR (Alcon) +3.5D or +3.00D Apodized trifocal: FineVision (PhysIOL): +1.75D, +3.50D Quadrifocal, non-apodized: Panoptix (Alcon): +2.17D, +3.25D

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51 ZOOM ON THE MOST IMPORTANT MARKET PLAYERS TRIFOCAL AT LISA TRI & PHYSIOL Reading Contrast sensitivity PanOptix Alcon material problems Symfony FAR & INTERMEDIATE No near vision Contrast sensitivity

52 1,50 Defocus curve - 6M 1,00 0,50 0,00 +4,0 D +3,5 D +3,0 D +2,5 D +2,0 D +1,5 D +1,0 D +0,0 D -0,5 D -1,0 D -1,5 D -2,0 D -2,5 D -3,0 D -3,5 D 677MY Based on clinical observation Bi Flex M shows clinically clear trifocal performance TRIFOCAL PANOPTIC SYMFONY

53 ZOOM ON.. CLINICAL FEEDBACKS

54 Clinical Studies at Glance 9 countries 2 continents 14 surgeons 3 prospective study 3 prospective study Quick evaluation results

55 Review of the Co-operating surgeons and Number of Operated Patients / Eyes STATE GERMANY HUNGARY CENTRUM / SURGEON No of patients No of eyes AK Bellevue Prof Böhnke Dr Dörner 7 14 Dr Kohm 6 12 Prof Nagy Dr Gyory Dr Nagymihaly STATE CENTRUM / SURGEON No of Patients No of EYES SWITZERLAND Dr Sutter 5 10 ISRAEL Prof Zadok SPAIN Baviera Group 4 8 PHILIPPINES Dr Naval FRANCE Dr Assouline AUSTRIA Prof Grabner BELGIUM Dr Van Acker CZECH REPUBLIC Prof Pasta TOTAL No of patients 393 No of eyes 786

56 * * Exact values of results might change by adding new patients results from other centres. 1,20 RESULTS**: 180 EYES VA BINOCULAR 6 months follow-up 1,00 0,80 0,60 0,40 0,20 - AK Bellevue Prof Böhnke Dr Dörner Dr Kohm Prof Pasta Dr Sutter* Dr Gyori prof Zadok* MEAN UnCorected VA (180 eyes) 6 months Follow-up far inter near FAR INTERMEDIATE (65 cm) NEAR MONOCULAR BINOCULAR *Prof Zadok: A const has been not optimized yet during his evaluation *Dr Sutter (5 pat.) : 1 patient SEQ = -1.0; 1 patient astisgm dpt

57 Comparison of Defocus curves Bi-Flex M and AT Lisa tri 839 MP (Zeiss)* (binocular, follow-up 6M) AT LISA Tri Bi-Flex M much better near VA, widen defocus curve for distance vision (in agreement with PAD technology), competitive intermediate vision (does not drop under 0.1 LogMar) to the trifocal IOL (Pasta J et al: presented at congress CSRKCH, CZ and at ESCRS London 2014) *P. Mojžíš, P. Peňa-Garcia, I. Liehneova, P. Žiak, J. Alio: Outcomes of a new diffractive trifocal intraocular lens. J Cataract Refract Surg; 40:60-69, 2014

58 Bi-Flex M contra ReStor (Alcon) Dunai A, Kranitzki K, Juhasz E, Nagy Z. ESCRS 2016

59 Bi-Flex M 1 year follow up (binocular) ESCRS 2016 Courtesy dr. Gyori, HU)

60 Contrast Sensitivity Photopic Mesopic In backlight Courtesy by Dr Gyory, HU

61 Contrast Sensitivity: Comparison of Bi-Flex 677MY and FineVision Photopic conditions Mesopic conditions Scotopic conditions Bi-Flex 677 MY (AVG) PhysIOL FineVision (AVG) 3 cpd 6 cpd 9 cpd 18 cpd Bi-Flex 677 MY (AVG) PhysIOL FineVision (AVG) 3 cpd 6 cpd 9 cpd 18 cpd Bi-Flex 677 MY (AVG) PhysIOL FineVision (AVG) 3 cpd 6 cpd 9 cpd 18 cpd Courtesy by Dr Gyory, HU

62 VFQ 25 - page 1 Courtesy dr. Gyori, HU) Visual Functioning Questionnaire (VFQ) No problem Mild Moderate Strong Bad N/A 50 patients / Score How much difficulty do you have with each of the following Please tick the number from 1 to 6 Glare/Flare (trouble seeing street signs due to bright light or oncoming headlight? Night vision Colour perception (trouble recognizing specific colours) Halos (rings around lights) Depth perception (trouble lining things up, pouring liquids or going down stairs) Distorted near vision (straight lines looked crooked close up) Distorted distance vision (straight lines looked crooked at distance) Blurred near vision Blurred far vision Double vision /?

63 VFQ 25 - page 2 50 patients Visual Functioning Questionnaire (VFQ) Response 1 to 6-point scale VISUAL LIFESTYLE ACTIVITIES score How much difficulty do you have with each activity due to your vision (without glasses or contact lenses) Watching TV or movies Playing or working outside Caring for/playing with children Reading the time on at alarm clock Seeing clearly when you wake up Reading the time on at wall clock Performing your job/hobbies Participating in sports/recreation Participating in social events Reading and near work activities Driving at night Driving when it is raining Using a computer Cooking Shopping Courtesy dr. Gyori, HU) Using a cell phone Shaving or putting on make up

64 Success of Progressive Bi-Flex M: Material - very low chromatic aberration Precision PAD Apodisation Special aberration on apodisative steps increased depth of focus 1 DIFFRACTIVE ARRAY combined with PAD technology which does not sacrifices the MTF peak for far and near vision thanks to all technical properties and technical developments progressive lens Clinical performance of Bi-Flex M supported by clinicalstudies is TRIFOCAL

65 References product websites Cionni, RJ et al: Get to Know the Defocus Curve, CRST, Nov