What type of lens is best after cataract surgery – multifocal or monofocal? It depends, study says
Multifocal intraocular lenses improve near vision without compromising distance vision. However, patients with these intraocular lenses may experience reduced contrast sensitivity and they may see haloes around lights. These are the conclusions of a study appearing in the September issue of Ophthalmology, the clinical journal of the American Academy of Ophthalmology, the Eye M.D. Association.
Monofocal lenses are the current standard of treatment, but usually require spectacles for near vision. The choice between the two types of lenses depends on patients motivation to be free of glasses and contact lenses and on their having realistic expectations about the outcomes and compromises involved.
In this systematic literature review and meta-analysis of eight randomized controlled trials, the researchers examined a number of different outcomes: distance and near visual acuity, both unaided and corrected; spectacle independence; depth of field; contrast sensitivity; glare; subjective assessment of quality of life or visual function; and surgical complications.
Though there was significant variability in outcomes among the trials, in general it was found that distance acuity was similar in multifocal and monofocal intraocular lenses, and that unaided near vision tended to improve with the multifocal lens. Independence from spectacles was found in 26 percent to 47 percent of patients with multifocal lenses, but only in 1 percent to 11 percent of those with monofocal lenses. In addition, multifocal lenses increased depth of field. However, the multifocal lens also reduced contrast sensitivity and resulted in the subjective experience of seeing haloes around lights.
"This study is a very realistic interpretation of the multifocal versus monofocal tradeoff," said Academy spokesperson Samuel Masket, MD, clinical professor of ophthalmology at the Jules Stein Eye Institute, UCLA School of Medicine. "The key to choosing multifocal lenses is strong motivation on the part of the patient to be free of glasses and contact lenses. The patient must consciously accept a reduction in the quality of vision in order to have just under a 50-50 chance of being spectacle free."
Dr. Masket said because of the information and advertising about refractive surgery outcomes, many patients have high expectations. "They often anticipate that lens replacement surgery is equivalent to refractive surgery. In fact, as the study indicates, current multifocal lenses may or may not match those expectations. He added that truly accommodating intraocular lenses, which move back and forth inside the lens capsule so the eye can focus both near and far, are currently under development and will probably replace the existing types of lenses in four to six years.
The American Academy of Ophthalmology is the worlds largest association of eye physicians and surgeons – Eye M.D.s – with more than 27,000 members worldwide. For more information about eye health care, visit the Academys partner Web site, the Medem Network at www.medem.com/eyemd. To find an Eye M.D. in your area, visit the Academys Web site at www.aao.org.
The most recent press releases about innovation >>>
Die letzten 5 Focus-News des innovations-reports im Überblick:
Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.
Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Mapping the interaction of a single atom with a single photon may inform design of quantum devices
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...