Abstract:Presbyopia occurs in the aging eye due to changes in the ciliary muscle, zonular fibers, crystalline lens, and an increased lens sclerosis. As a consequence, the capacity of accommodation decreases, which hampers to focus near objects. With the aim of restoring near vision, different devices that produce multiple focuses have been developed and introduced. However, these devices are still unable to restore accommodation. In order to achieve that goal, dual-optic accommodating Intraocular Lenses have been desig… Show more
“…Others seem to achieve an increased level of spectacle independence, but principally from pseudoaccommodative mechanisms such as multifocality, rather than a change in optical power (Pepose et al, 2017a). Newer designs (few that have been clinically tested) include dual optics, shape changing optics and refractive index changing optics (Ben-Nun and DeBoer et al, 2016;McCafferty and Schwiegerling, 2015;Tomas-Juan and Murueta-Goyena Larranaga, 2015). The latter research on possible future advances in 'accommodating' implants is discussed in section 7.…”
Presbyopia is a global problem affecting over a billion people worldwide. The prevalence of unmanaged presbyopia is as high as 50% of those over 50 years of age in developing world populations, due to a lack of awareness and accessibility to affordable treatment, and is even as high as 34% in developed countries. Definitions of presbyopia are inconsistent and varied, so we propose a redefinition that states "presbyopia occurs when the physiologically normal age-related reduction in the eye's focusing range reaches a point, when optimally corrected for distance vision, that the clarity of vision at near is insufficient to satisfy an individual's requirements". Strategies for correcting presbyopia include separate optical devices located in front of the visual system (reading glasses) or a change in the direction of gaze to view through optical zones of different optical powers (bifocal, trifocal or progressive addition spectacle lenses), monovision (with contact lenses, intraocular lenses, laser refractive surgery and corneal collagen shrinkage), simultaneous images (with contact lenses, intraocular lenses and corneal inlays), pinhole depth of focus expansion (with intraocular lenses, corneal inlays and pharmaceuticals), crystalline lens softening (with lasers or pharmaceuticals) or restored dynamics (with 'accommodating' intraocular lenses, scleral expansion techniques and ciliary muscle electrostimulation); these strategies may be applied differently to the two eyes to optimise the range of clear focus for an individual's task requirements and minimise adverse visual effects. However, none fully overcome presbyopia in all patients. While the restoration of natural accommodation or an equivalent remains elusive, guidance is given on presbyopic correction evaluation techniques.
“…Others seem to achieve an increased level of spectacle independence, but principally from pseudoaccommodative mechanisms such as multifocality, rather than a change in optical power (Pepose et al, 2017a). Newer designs (few that have been clinically tested) include dual optics, shape changing optics and refractive index changing optics (Ben-Nun and DeBoer et al, 2016;McCafferty and Schwiegerling, 2015;Tomas-Juan and Murueta-Goyena Larranaga, 2015). The latter research on possible future advances in 'accommodating' implants is discussed in section 7.…”
Presbyopia is a global problem affecting over a billion people worldwide. The prevalence of unmanaged presbyopia is as high as 50% of those over 50 years of age in developing world populations, due to a lack of awareness and accessibility to affordable treatment, and is even as high as 34% in developed countries. Definitions of presbyopia are inconsistent and varied, so we propose a redefinition that states "presbyopia occurs when the physiologically normal age-related reduction in the eye's focusing range reaches a point, when optimally corrected for distance vision, that the clarity of vision at near is insufficient to satisfy an individual's requirements". Strategies for correcting presbyopia include separate optical devices located in front of the visual system (reading glasses) or a change in the direction of gaze to view through optical zones of different optical powers (bifocal, trifocal or progressive addition spectacle lenses), monovision (with contact lenses, intraocular lenses, laser refractive surgery and corneal collagen shrinkage), simultaneous images (with contact lenses, intraocular lenses and corneal inlays), pinhole depth of focus expansion (with intraocular lenses, corneal inlays and pharmaceuticals), crystalline lens softening (with lasers or pharmaceuticals) or restored dynamics (with 'accommodating' intraocular lenses, scleral expansion techniques and ciliary muscle electrostimulation); these strategies may be applied differently to the two eyes to optimise the range of clear focus for an individual's task requirements and minimise adverse visual effects. However, none fully overcome presbyopia in all patients. While the restoration of natural accommodation or an equivalent remains elusive, guidance is given on presbyopic correction evaluation techniques.
“…Overall, patient satisfaction is also variable (10%–80%) 19 and might be a consequent to the lack of standardization in present studies. 72 Therefore, more studies are required to evaluate clinical outcomes of present accommodative IOLs. 19 , 20 , 72 …”
Section: Resultsmentioning
confidence: 99%
“… 72 Therefore, more studies are required to evaluate clinical outcomes of present accommodative IOLs. 19 , 20 , 72 …”
PurposeTo present potential benefits as well as limitations of premium intraocular lens (IOL) use, and provide insight in future of premium cataract surgery.MethodsBibliographic research was performed in PubMed/Medline database, and the most recently updated papers were evaluated. Keywords used were: premium intraocular lens, multifocal intraocular lens, toric intraocular lens, toric multifocal intraocular lens, accommodative intraocular lens, and the respective brand names.ResultsMultifocal IOLs provide uncorrected distance visual acuity (UDVA) of 0.03 logMAR in 82.3%–95.7% of patients and overall spectacle independence in 81%–85% of patients. Toric IOLs provide UDVA of 0.3 logMAR in 70%–95% of patients, residual astigmatism of 1 D or less is noted in 67%–88% of patients, and spectacle independence is reported in 60%–85% of patients. Toric multifocal IOLs provide UDVA of 0.3 logMAR in 92%–97% of patients, and spectacle independence is reported in 79%–90% of patients. Accommodative IOLs represent intensively developing field in ophthalmology, and the results are still variable depending on the IOL model.ConclusionsPremium IOL technology and advanced surgical techniques have significantly improved postoperative visual outcomes. Future developments will potentiate development of new premium IOL designs that will provide spectacle independence and excellent visual outcomes after cataract surgery.
“…In the literature, there are several studies regarding the outcomes of single optic AIOLs (10,(16)(17)(18)(19)(20)(21)(22)(23)(24). The most evaluated one was Crystalens, which is the first Food and Drug Administration approved AIOL (7,8,19).…”
To compare distance and near visual acuity along with accommodative amplitude in eyes implanted with the Tetraflex and the Tek-clear accommodating intraocular lenses (AIOLs). Methods: Comparative, prospective, non-randomized study. Thirty-eight eyes of 26 patients implanted with the Tetraflex (17 eyes) and Tekclear (21 eyes) AIOLs were enrolled. Uncorrected distance visual acuity (UCDVA), best-corrected distance visual acuity (BCDVA), uncorrected near visual acuity (UCNVA), distance corrected near visual acuity (DCNVA), best-corrected near visual acuity (BCNVA) and spherical equivalent refraction were the parameters evaluated postoperatively. Also, the accommodative amplitude was assessed with subjective defocus method and objective anterior chamber depth measurement before and after the topical application of pilocarpine using a Scheimpflug-Placido disc topographer at postoperative month 3 and 6. Results: No statistically significant difference was found between the two AIOL types in regards to BCDVA, DCNVA, and BCNVA at months 1, 3, and 6 (p>0.05). The mean UCDVA was significantly better in Tetraflex implanted eyes (p=0.001, p=0.002, p=0.008), whereas the mean UCNVA was significantly better in Tek-clear implanted eyes (p=0.008, p=0.01, p<0.0001) at postoperative month 1, 3, and 6, respectively. Both subjective and objective accommodative amplitude assessments did not display a significant difference between the two groups at month 6 (p>0.05). Conclusion: The Tetraflex accommodative IOL seemed to be better at UCDVA, whereas Tek-clear seemed better at UCNVA. The accommodation range of Tetraflex and Tek-clear lenses was comparable.
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