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Ophthalmic lenses
Published in Pablo Artal, Handbook of Visual Optics, 2017
Intraocular lenses had been implanted since 1999 in order to correct high ammetropies, without removing the eye lens. This lens is called a phakic intraocular lens, since the eye lens remains in the eye. Naturally, an aphakic eye with an intraocular lens, cannot accommodate, like in very old people. Presently, bifocal or multifocal intraocular lenses are being implanted, to allow clear near vision, but many practical problems still have to be solved to find a perfect multifocal intraocular lens.
Performance of a new device for the clinical determination of light discomfort
Published in Expert Review of Medical Devices, 2020
Robert Montés-Micó, Alejandro Cerviño, Noelia Martínez-Albert, José V. García-Marqués, Sarah Marie
Inclusion criteria considered volunteer healthy participants willing to follow the protocol and able to read, comprehend, and sign the informed consent form. A complete clinical assessment was carried out to ensure that subjects met the requirements for enrollment. Subjects who were participating in another study which might influence vision or interfere with study assessments were excluded. As specific inclusion criteria would be age between 20 and 70 years, a best distance-corrected visual acuity (BCVA) was set at +0.10 logMAR or better in each eye. Exclusion criteria included aphakia or pseudophakic multifocal intraocular lens (IOL), any current or evolving pathology manifested in the eye or the appendages which might have an influence on vision, or interfere with study assessments (e.g. age macular degeneration or glaucoma), any previous ocular surgery, any untreated and/or uncontrolled systemic conditions which might have an influence on vision, or interfere with study assessments (e.g. uncontrolled diabetes or uncontrolled high blood pressure), any medical treatment, or medication which might have an influence on vision or interfere with study assessments (e.g. antidepressants, tranquilizers, antipsychotics, or drugs with atropinic effects), migraine, or epilepsy. Although monofocal IOLs were not considered an exclusion criterium during recruitment, only two male subjects within the 60–70 years-old group had monofocal IOL implanted bilaterally.
A perspective of contemporary cataract surgery: the most common surgical procedure in the world
Published in Journal of the Royal Society of New Zealand, 2020
Charles N. J. McGhee, Jie Zhang, Dipika V. Patel
A large prospective clinical study evaluating the efficacy of diffractive multifocal IOLs implanted between 2004 and 2008 reported spectacle independence being achieved in 82%. Unaided distance vision was ≥6/12 in 96.5% of eyes and ≥6/6 in 52% of eyes, with 95% of eyes achieving unaided reading vision of N5 at 33 cm. Patient satisfaction with visual outcome was high with only 10.2% of patients reporting minor dysphotopsia (halos and undesired visual phenomena) associated with the IOL (Altaie et al. 2012). A Cochrane review (2016) of 20 studies concluded that those with a multifocal intraocular lens may have better near vision and may be less likely to need spectacles compared with people with monofocal lenses. However, this was low certainty evidence. They also concluded that multifocal intraocular lenses were associated with more visual problems, such as glare or haloes compared to monofocal lenses (de Silva et al. 2016).