ref : med 2010-ppt-01 why a new iol ? to integrate latest surgeons' requirements in terms of :...
TRANSCRIPT
Ref : Med 2010-ppt-01
Why a new Iol ?
To integrate latest surgeons' requirements in terms of :
• Asphericity • Protection against maculopathies
• Perfect and stable axial positioning
• Low PCO rate
• Ease of handling and injection through small incision
Ref : Med 2010-ppt-01
In more details...
Bi-Flex has been developed taking into considerations that it should offer :
• An improved vision quality whilst retaining an excellent depth of field
• The potential to opt for the natural yellow filter and thus respect the natural evolution of the crystalline lens
• An adequate design to guarantee an implant centred with stable axial positioning immediately after surgery
• An easy handling and injection whatever the surgical programme used (including operations where small-size incisions are used)
• A pertinent material for total biocompatibility with the ocular tissues and with greatly reduced post-operative inflammation rates.
Ref : Med 2010-ppt-01
What are the results?
An intra-ocular lens with all the necessary qualities
With : For :
• Aspheric lenses• Limiting optical aberrations (spherical, coma, chromatic) and improvement of the visual comfort of patients
• Access to a “natural” yellow filter which reduces the transmission of wavelengths of less than 500nm
• Prevention against the toxicity of blue light without alteration of colour vision
• Optimised design• optimal stability and better refractive predictability
• Combination of hydrophobic and hydrophilic monomers
• A high biocompatibility, a low PCO rate and a perfect pseudoplasticity enabling injections through small incision
Ref : Med 2010-ppt-01
4 major assets for
1. Adapted design for optimised mechanical behaviour and optical quality
2. A material recognised throughout the profession
3. A “natural” yellow filter for better protection of the macula
against the blue light
4. Aspheric implants to limit optical aberrations and improve the visual
comfort of patients
Ref : Med 2010-ppt-01
Asset N°1 Adapted design for optimised mechanical behaviour and optical quality
With: • A design suitable to standard surgical techniques
(co-axial, bi-axial, micro-axial, etc.) enabling insertion through incisions of less than 2.2 mm, with no risk of tearing.
• Excellent haptic compressibility to ensure a perfect adaptability to the size of the bag
• An aspheric optical design for implants immune to the usual defects in positioning such as decentration or tilting.
Ref : Med 2010-ppt-01
Zoom on design
The designs guaranteed by the Medicontur expertise and by its 20 years of experience : the design combines all the qualities of monobloc implants with those of 3-piece implants for:
• Excellent stability
• Optimised symphysis
• Very limited capsular retraction
• Complete ease-of-use
Ref : Med 2010-ppt-01
Zoom on the design
In detail:
• A square edge over 360° for effective control of the development of PCO.
• A real 6 mm optic size
• Flat implant but with a posterior vaulting
• Perfect contact zone with the capsulefor a stable implant in the plane and excellent refractive results.
Ref : Med 2010-ppt-01
Zoom on the Bi-Flex design
In detail: (continuation)
• Discontinuities on the optical diameter for Bi-Flex, positioned at 90°to each other to stabilise the optic, fix the implant against the capsule and have better control of post-operative rotation.
• An optimised elbow-shaped bend for Bi-Flex, with a wide loop connection and a wider space (Dolphin zone) for increased stability, optimal flexion without overlap of the end of the loop on the optic and perfect symphysis with reduced risk of capsular retraction.
• Blunt loop ends for Bi-Flex for trauma-free insertion of the implant.
Ref : Med 2010-ppt-01
Note the approx. 60°contact angle and the decentralised IOL in the lower right.
ACR6D-SE Corneal design in a flexible ring
Near the tip of the loop there is an area of no contact.
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63° contact angle with simulation of rigid capsular sac of 9.0 mm diameter.
Note that only the central part of the loops rests on the capsular equator.
ACR6D-SE Corneal design in a rigid ring
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74°contact angle with simulation of rigid capsular sac of 9.0 mm diameter.
Note the good contact (homogeneous) of the loops with the capsular equator for their entire length.
Xcelens IDEA design in a rigid ring
Ref : Med 2010-ppt-01
Bi-FLEX
Bi-Flex design in a rigid ring
91°contact angle with simulation of rigid capsular sac of 9.0 mm diameter.
Note the good contact (homogeneous) of the loops with the capsular equator for their entire length.
In total Bi-Flex has more than 180°contact angle with the capsular
bag.
Ref : Med 2010-ppt-01
The square-edges of the Flex range are
perfectly sharp thanks to a new
technology : the polish free method.
Square edges ACR6D-SE
versus ACR6D-SE: comparison SE
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The Bi-Flex range is compatible with the MedJet injection system for
incision sizes 2.2 mm and sub 2.0 mm
Ref : Med 2010-ppt-01
Asset n°2
A material recognised throughout the profession :
the 25% Hydrophobic/Hydrophilic material
Ref : Med 2010-ppt-01
Asset N°2 A material recognised throughout the profession : the 25% Hydrophobic/Hydrophilic material
To note:
• Copolymer material (25%) combining hydrophobic and hydrophilic monomers for additional properties.
• Excellent pseudo-elasticity for the implants, due to the hydrophobic monomers.
• Post-operative inflammation rate greatly reduced due to the hydrophilic monomers.
• Implants totally compatible with the ocular tissues.
Ref : Med 2010-ppt-01
What is the winning combination?
• 2-HEMA : 2-hydroxyethyl methalycrate
A hydrophilic monomer
• EOEMA : 2-ethoxyethyl methalycrate
A hydrophobic monomer
To form a copolymer with: • Lower water content• Higher refractive index• Improved mechanical properties.
For improved mechanical properties : • superior pre-insertion folding capacities• post-insertion unfolding and optical properties perfect recovery.
Ref : Med 2010-ppt-01
Medicontur foldable raw material : a combination of two monomers
- HEMA, highly hydrophilic monomer
Pure HEMA = 38% water content
• BIOCOMPATIBILITY
- EOEMA, hydrophobic monomer
Approximately 2% water content
•ELASTICAL PROPERTIES
•SOFTNESS
Ratio EOEMA - HEMA
EOEMA
36%
HEMA
64%
25% water content after combination of the two monomers, to form an highly biocompatible polymer
Mixing hydrophily and hydrophoby
Ref : Med 2010-ppt-01
MMAMethylmetacrylate
RAYNERB&L
CORNEAL
HEMAHydroxyethylmetacrylate
Rare IOLs in pure HEMAPALMLENS (CORNEAL) EOEMA
Etoxyethylmetacrylate
Flex range lens
The Flex range raw material specificity : the longest chain
Comparison with other polymers : focus on the molecular scale
Ref : Med 2010-ppt-01
Apart from design, chain length has a proven effect against cell adhesion :
Hydrogel MMA 26% Bi-Flex, Q-Flex, Z-Flex material
Anti-PCO behaviour
A long chain acts as a « molecular eyelash »to prevent cell adhesion and protein deposit
Our raw material : low adhesion for a low PCO rate
Ref : Med 2010-ppt-01
A long chain of medium hydrophily :an essential specification for mini & micro cataract surgery
pHEMA Hydrogel MMA 26% Bi-Flex material
• Lower risk of tears with the Flex range than with HEMA thanks to a reduced hydrophily and the tensile strength of hydrophobic monomers
• Much softer elasticity properties of the Flex range, 3 times better than MMA26% material
Bi-Flex, Z-Flex & Q-Flex ’lens raw material : perfect for any kind of incision
Soft and re-arrangeable innovative matrix
Ref : Med 2010-ppt-01
What are the properties of the IOLs conferred by this material?
Folding and Unfolding Good to Excellent
Memory Excellent
Biocompatibility Excellent
Average visual acuity Good to excellent, with no inflammation
Dislocation None (no cases reported)
Opacification None (no cases reported)
Incidence of PCO Very Low
Yag laser compatibility Excellent
Ref : Med 2010-ppt-01
Asset n°3
A “natural” yellow filter for better protection
of the macula against the blue light
Ref : Med 2010-ppt-01
Asset N°3 A “natural” yellow filter for better protection of the macula against blue light
For:
• Increasing the protection of the macula
the defence mechanisms of which change with age
• Compensating the disappearance of the yellow pigment
which has developed in the lens over the years, and which reinforces the protection
of the retina against photo-toxic short waves.
• Totally preserving colour vision and excellent contrast perception
because the filtration does not interfere with the chromatic sensitivity of the retina.
Ref : Med 2010-ppt-01
Zoom on the compensation of the disappearance of the yellow pigment
1. The natural crystalline lens is replaced>> The “natural” yellow filter barrier disappears
2. The macula does not benefit anymore from the “natural” yellow filter barrier.Macula’s defense mechanisms are also altered with age.>> It is dangerously exposed to blue light.
That is why Bi-FLEX 677 ABY, Q-FLEX 640 ABY, Z-FLEX 690 ABY
include a protective filter adapted to these wave lengths.
Ref : Med 2010-ppt-01
Nature’s own solutions are the best…
Why our Medicontur yellow filter is said to be “natural”?
Because our material integrates the same UV-A blocking and violet light
filtering chromophore that is in the human crystalline lens
Why is Medicontur natural yellow filter superior?
Because it protects the retina without blocking the required blue light.
Medicontur natural yellow filter provides complete natural protection without
making the retina losing its contrast sensitivity or colour perception.
Ref : Med 2010-ppt-01
Conclusion on Yellow natural filter
The Medicontur’s approach aiming at protecting the retina from UV-A and
violet light is based upon nature’s own solutions.
Medicontur IOL material thus integrates the same UV-A blocking and violet
light filtering chromophore that is in the human crystalline lens.
The Medicontur natural Yellow filter is superior to any other yellow IOL
material because it protects the retina without blocking the required blue
light. It provided complete natural protection without making the retina
loosing its contrast sensitivity or colour perception.
Ref : Med 2010-ppt-01
Asset n°4
Aspheric implants to limit optical aberrations and
improve the visual comfort of patients
Ref : Med 2010-ppt-01
Asset N°4 Aspheric implants to limit optical aberrations and improve the visual comfort of patients
With:
• A neutral asphericity approach, which constitutes the best choice in case of unknown individual corneal aberration
• The retention of the natural physiological aberrations of the cornea, mainly sphericity, to provide the patient with good quality vision and depth of field.
• The recognition of the physiological ocular asymmetries (kappa angle) in the design of FLEX lenses to minimise the astigmatism and coma aberrations.
Ref : Med 2010-ppt-01
What is an aberration?
An aberration is an optical limitation that reduces image quality.
It usually results in a local or global blur.It can also produce distortion or color trouble.
There are 3 main aberration types:
• Chromatic aberration
• Coma aberration
• Spherical aberration
Ref : Med 2010-ppt-01
The image of a point is a circular spot with annular separated colors :yellow, red and blue
Chromatic aberration
Ref : Med 2010-ppt-01
Coma aberration
The image of a point is a comet-like spot :the image is blurry, particularly at the comet tail.The more tilted the lens is, the more aberrated
Ref : Med 2010-ppt-01
Spherical aberration
The image of a point is a circular spot : the image is blurry.The more the power is or the bigger the pupil is, the more aberrated.
Ref : Med 2010-ppt-01
+-No SA
or slighly +
This compensation effect of the crystalline lens has been fully described in literature [9]
++ SA ++ Increased spherical aberrations
PHAKIC EYE : COMPENSATION EFFECT
PSEUDOPHAKIC EYE with SPHERICAL IOL :
Ref : Med 2010-ppt-01
NEUTRAL CORRECTING
PROSGood depth of field
Not sensitive to tilt and decentration
Sharp image
CONS Less precise image qualityNo depth of field
Sensitive to tilt and decentration
OUR APPROACH
No spherical aberration Spherical aberration
CORRECTING IOLNEUTRAL IOL
+
0
+
-
+
CURRENT ASPHERIC IOLS : 2 major approaches
Ref : Med 2010-ppt-01
Why to chose a neutral asphericity?
Because :
1. The human eyes are naturally asymmetrical >> there is a benefit to have a lens not sensitive to tilt and decentration
2. Bi-Flex specific designs are optimized >> to minimize coma and astigmatism aberrations
3. While preserving natural and physiological spherical aberrations of the cornea >> to improve depth of field.
Ref : Med 2010-ppt-01
The optical result in the eye
With
the image on the retina is the sharpest possible created by a single lens – not contributing to any pre-existing spherical aberration in the eye.
• Flex IOLs
• Spherical
• Flex IOLs
• Spherical