Truly Accommodating Iols Set the Trend for Presbyopia Correction Refractive Refractive
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Lens Truly accommodating IOLs set the trend for presbyopia correction Refractive Refractive Samuel Masket Courtesy of Samuel Masket MD 2006 ASCRS survey reveals that greater than 200,000 presbyopic USFDA data for ReSTOR IOL indicates very high levels of patient satisfaction Postoperative changes in the lens capsule bag, specifically fibrometaplasia may influence IOL’s were implanted in the US results with accommodating IOLs. Currently, sealed capsule irrigation, from Maloof, is the only available strategy; however it is used infrequently Stefanie Petrou Binder MD ensues and patients with increasing cylinder through the hard ring, leading to bulging and by multifocality or increased focus depth, in Nürnberg become much more susceptible to blurred a simulation of accommodation. rather than lens movement or shape change, vision, he said. A recent study on 10 eyes with advanced he said. In fact, the use of presbyopic IOLs TRULY accommodating, physiologic IOLs The Synchrony IOL is comprised of two macular degeneration revealed improved according to an ASCRS learning survey with fewer optical side effects are the hope lenses: an anterior +32D optic and a variable UCVA with the NuLens. Nonetheless, showed that US ASCRS members implanted for the future in presbyopia correction, as posterior minus optic. It has spring-like patient satisfaction remains to be seen, due 216,000 IOLs, of which 62 per cent were compared with pseudo-accommodating haptics to store energy for forward and to an ‘opposite accommodation’ effect noted ReSTOR lenses, 28 per cent ReZOOM, and IOLs, said Samuel Masket MD during his backward motion.The principle behind the with these lenses.This manifests as silicone 10 per cent Crystalens. presentation of the Ridley Lecture at the lens is that with accommodation, the zonules bulge and dioptre change in cycloplegia and annual congress of the German Ophthalmic relax, and the capsular bag expands in an loss of accommodation with ciliary Rigorous criteria for success Surgeons (DOC). anterior-posterior dimension as the lenses muscle contraction. “Single-lens, rigid-optic IOLs with flexible Success with multifocal IOLs depends on separate, yielding increased optic power. Beyond the Synchrony and NuLens, new haptics (HumanOptics 1CU, CrystaLens) astigmatism control, accurate biometry, ideas in IOL design set the stage for were the first of these devices to reach the appropriate formulae, and adjusting the interesting future trials. For instance, the market but proved to be limited in their outcome enhancements. Undesired optical ‘Powervision’ IOL (Power Vision) involves a accommodative function.True “True accommodative side effects are higher in these patients than dynamic optic with fixed haptic.The ‘fluid accommodative function depends on many in patients receiving monofocal lenses, such function depends on many vision IOL’ (Power Vision),with implantations factors including the IOL design concept and as severe halos occurring for instance in up scheduled within upcoming months, may require long-term flexibility of the lens to five per cent of patients with the ReSTOR factors including the IOL incorporates new applied fluidic technology capsule,” he reminded the gathering. as opposed to in under one per cent of in a single-piece IOL.The idea is that upon The Visiogen Synchrony dual-lens monofocal patients, Dr Masket pointed out. design concept and may accommodative stimulation, fluid (liquid intraocular telescope IOL mimics true In addition, multifocal success relies on silicone) is pumped (reversibly) through accommodation by maintaining 20/25 visual excluding patients with co-morbidities that require long-term flexibility peripheral channels into a bladder in the acuity at all ranges, according to the would reduce the performance of these centre of the lens, which alters the radius of outcome of a comparative investigation that lenses, such as: maculopathy (age-related of the lens capsule” the curvature and moves the lens forward, included the Synchrony and ReZOOM and macular degeneration, epiretinal membrane), affecting an increase in IOL power for near ReSTOR multifocal IOLs. (Ossma, Etal – keratopathy, optic neuropathy, patients with A high-definition UBM investigation vision purposes, Dr Masket observed. ASCRS San Diego.) prism in glasses, and those with (Ossma, Etal – ASCRS San Diego) verified that The Medennium Smart IOL, a dynamic The pseudo-accommodative devices difficult/negative personalities. the two-lens optics were positioned close single-piece optic IOL, is a full-sized IOL (9.3 (ReSTOR (Alcon), ReZOOM (AMO)) Implanted in the right candidate, together (non-accommodated position) x 3.5mm) designed to fill the capsule bag performed less well at intermediate and multifocals can be extremely well tolerated. during distance vision and that the anterior through a 3.5mm incision, which represents close visual ranges, Dr Masket explained. When asked if they would want the same optic moved forward with near stimulation a different approach to achieving true Reading speed and contrast sensitivity were IOL implanted again, over 90 per cent of of the fellow eye (accommodated position: accommodation. Similarly, the LiquiLens similar in the Synchrony and the ReSTOR patients from different FDA trials said yes. two lens optics far apart), Dr Masket said. (Vision Solutions Technologies) offers a under photopic conditions, but only the A final approach that merits some Other lens designs offer alternatives for unique accommodation solution by achieving Synchrony sustained reading speed and attention is the AcuFocus.The AcuFocus achieving true accommodation, defined by different optical effects according to patient contrast of vision under reduced corneal inlay, a 10 µm-thin device placed in the Helmholz theory that says either a eye position.This dual liquid gravity light conditions. the LASIK bed, uses a 1.6cm reduced transient increase in optical power of the dependent IOL has an optic chamber The ReZOOM and ReSTOR IOLs had pupillary aperture to create a pin hole IOL (shape change) and/or a transient containing two immiscible fluids, each with lower reading speed and reduced contrast optical aperture effect for increased depth of anterior movement of the optic, or both, different indices of refraction.The liquids sensitivity due to the principle of light focus, but does not reduce distance need to occur.The NuLens (Nulens, Ltd), for shift as the eye looks down or up, giving division inherent in multifocal lenses, Dr visual acuity. instance, with its soft pliable silicone centre different near and far optical effects. Masket said. Only roughly 90 per cent of and hard exterior ring/plate, is an interesting While true accommodating IOLs may [email protected] transmitted light is useable with refractive option for achieving true accommodation. appear in the near future, the current lenses and half of the light is divided The hard plate rests in the ciliary sulcus and presbyopia market is still largely dominated between distance and near.As a result of the causes indentation of the silicone centre by pseudo-accommodative devices, defined division of light energy, reduced contrast 22.