Presentation on theme: "Dr H. Razmjoo Isfahan University of Medical Sciences Multifocal IOLs."— Presentation transcript:
Dr H. Razmjoo Isfahan University of Medical Sciences Multifocal IOLs
Monovision Refractive Diffractive Accommodative
50’s to the mid 60’s Cataract starting to compromise quality of vision Active lifestyle Concerned about their appearance & ‘quality of life’ Do not want to ‘get old’ Spending on lifestyle enhancing procedures Realistic Expectations Motivated Asks lots of questions
Wants to be less dependent on glasses Understands the limitations Willing to accept several months to adapt to their new visual system
Significant dry eyes Corneal scarring Pupil size < 2.5 mm Monofocal implant in first eye Uncorrected post-op astigmatism > 0.5 D Unstable capsular support Someone who demands perfect vision
Refractive lens Delivers good near, distance and intermediate vision
The most common concerns Distance blur Monocular diplopia Object glow Ghosting Halos at night These are the biggest post-op challenges
The 3.5 D add at the IOL plane provides for fairly good near vision
Diffractive technology Silicone material Uses “apodization” to soften blur and sharpen vision Provides excellent VA at near, distance and intermediate ranges
High quality uncorrected near and distance vision with 20/40 or better intermediate vision without movement of the IOL 80% Overall Spectacle Freedom Nearly 94% of patients would have the lens again
The ReSTOR IOL is an IOL that provides significant magnification. Many patients spend 10 to 15 years gradually holding reading materials farther away. By the time a patient is 55 years old, with 55 to 60 years being the typical age range for presbyopic IOL exchange, the patient is holding reading materials at 14 to 20 inches away from his or her eyes.
After ReSTOR IOL implantation set at D to +0.5 D, a patient has near vision of 9 to 10 inches. However, the ReSTOR IOL does not provide a significant increase in intermediate vision.
Tecnis multifocal (AMO) Sofport AO (Bausch & Lomb)
Haloes and glaare at night are common- these diminish with time Longer adaptation period – may take weeks or months for patients to accept their “new” visual system Near vision may be fuzzy to myopes May need reading specs for prolonged nearpoint work
In the United States, a new category of intraocular lenses was opened with the approval by the Food and Drug Administration in 2003 of multifocal and accommodating lenses. The aim of the procedure is to allow the eye to focus on near as well as distant objects without regular need to use glasses. These lenses have areas of different refractive powers and allow both near and distant images to be focused on the retina simultaneously. The brain is then able to select the required image for attention.
problems with intermediate vision reduced contrast sensitivity halos glare ‘Vaseline vision’ / waxy vision reduced tolerance to astigmatism
Clinicians wishing to undertake implantation of multifocal (non-accommodative) IOLs during cataract surgery should ensure that patients understand the risks of the procedure, including the possibilities of halo and glare, and reduced contrast sensitivity. Patients should also be made aware that the lenses may be difficult to remove or replace. They should be provided with clear written information.
To incorporate the strengths of each type of IOL, some eye surgeons recommend using a multifocal IOL in one eye to emphasize close reading vision and an accommodating IOL in the other eye for further midrange vision. This is called "mix and match." Distance vision is not compromised with this approach, while near vision is optimized.
Spherical aberration correction to essentially zero chromatic aberration reduction A pupil-independent, full-diffractive posterior surface High-quality vision in all light conditions 28
29 Posterior side Anterior side Haptics offset for 3 points of fixation 13.0 mm overall diameter Posterior diffractive surface 6.0 mm optic diameter Frosted, continuous 360° posterior square edge TECNIS ® IOL wavefront- designed aspheric surface
Full diffractive posterior surface Pupil-independent Wavefront-designed aspheric anterior surface Light distribution 50/50 Optical power add +4.0 D To optimize acuity at preferred reading distance of 33 cm 30
Under low-contrast conditions, contrast sensitivity is reduced with a multifocal lens compared to a monofocal lens. Therefore, patients with multifocal lenses should exercise caution when driving at night or in poor visibility conditions. 31
Precautions: The central one millimeter area of the lens creates a far image focus, therefore patients with abnormally small pupils (~1 mm) should achieve, at a minimum, the prescribed distance vision under photopic conditions; however, because this multifocal design has not been tested in patients with abnormally small pupils, it is unclear whether such patients will derive any near vision benefit. 33
Manual Refraction Autorefractors may not provide optimal postoperative refraction of multifocal patients; manual refraction is strongly recommended.
Emmetropia should be targeted as this lens is designed for optimum visual performance when emmetropia is achieved. Care should be taken to achieve centration.
Correcting spherical aberration (SA) to zero results in sharper focus of light and therefore sharper vision at both near and distance. TECNIS ® Multifocal IOLReSTOR ® +3.0 IOL 36 * *In the average cataract patient *
There is a measurable difference An IOL that fully corrects spherical aberration can provide a 13% increase in contrast over an IOL that leaves +0.1 residual spherical aberration 37
Several studies have shown the correction of chromatic aberration and spherical aberration together is more beneficial than the sum of the two individual corrections. 38
As the pupil widens in mesopic conditions: TECNIS ® Multifocal IOL is pupil-independent so light is still distributed equally to near and distance focal points, retaining high-quality near vision The apodized design functions as a monofocal lens on the outer perimeter, therefore distributing more light to distance and degrading the quality of near vision TECNIS ® Multifocal IOLReSTOR ® +3.0 IOL 39
The Rayner M-flex™ Multifocal IOL
The Rayner M-flex™ (630F) Multifocal IOL
M-flex™ is a multi-zoned, refractive, aspheric multifocal intraocular lens (MIOL) indicated for those patients requiring a degree of pseudoaccommodation.
M-flex™ is a single-piece, hydrophilic acrylic injectable MIOLwhich can be considered to be the multifocal analogue of Superflex™, having an optic diameter of 6.25mm and an overall length of 12.50mm
M-flex™ is based on multi-zoned refractive aspheric optics with either 4 or 5 refractive zones (depending on base power), providing an additional +3.0D of refractive power in the IOL plane, which is equivalent to +2.25D in the spectacle plane The refractive zones around the central (1.75mm) distance zone are annular and alternate between distance and near focus with a 60:40 split (Distance:Near)
The outer haptics begin to take up the compression due to capsular contraction Progressive resistance to the compression forces is generated as the outer and inner haptics engage 1) The outer and inner haptics lock together 2) The IOL assumes an oval configuration 3) The haptic dynamics change, increasing haptic rigidity and providing superior capsular stability 10.0mm 9.5mm 10.5mm
Note the perfectly symmetrical haptic compression
M-flex™ (630F) Sphere D to D in 1.0D increments D to D in 0.5D increments Power addition +3.0D
No contraindications e.g., recurrent severe inflammation or uveitis Bilateral implantation Postoperative astigmatism <0.75 D Postoperative emmetropia or max. <0.75 D hyperopia Patient motivation (e.g., high diopter glasses, hyperopia, spectacle independence) Visual expectations of the patient 52
Macular pathologies, glaucoma with severe visual field loss Monofocal IOL already in one eye (relative exclusion) Unrealistic visual expectations Happy with reading glasses Surgical complications, such as capsulorhexis tear, capsular folds, fixation in sulcus Patient is at risk for developing PCO 53