Children who wore contact lenses overnight as part of their orthokeratology regime developed corneal ulcers, resulting in corneal scarring and vision loss. According to a case study from China, appearing in the March issue of the American Academy of Ophthalmologys clinical, peer-reviewed journal, Ophthalmology, six children, nine to 14 years of age, were treated for bacterial eye infections after wearing the contact lenses eight to 12 hours each night.
Orthokeratology is a controversial, nonsurgical option for correcting the refractive error myopia, or nearsightedness. According to the study from the Department of Ophthalmology and Visual Sciences at the Chinese University of Hong Kong, myopia is one of the most common ocular conditions in humans. It affects 25 percent of the United States population between the ages of 12 and 54 years of age, and is thought to affect up to 71 percent of the adult Chinese population in Hong Kong.
Orthokeratology was first developed by optometrists during the 1960s. The procedure consists of fitting a series of rigid gas-permeable lenses (OKLs) to modify the shape of the cornea, resulting in a temporary reduction, modification or elimination of the refractive error. Although not widely used in the United States, this procedure is gaining popularity, especially in countries such as China. However, the study states the role of orthokeratology in arresting or slowing the progression of refractive errors in children, and its long-term effects, are not clear.
According to the study, other problems with OKLs are:
"Parents certainly want the best for their children," said Academy spokesperson Thomas L. Steinemann, of the MetroHealth Medical Center Eye Clinic in Cleveland and associate professor of ophthalmology at Case Western Reserve Universitys Department of Ophthalmology. "However they need to consider this option carefully. Corrections to the refractive error may be only temporary. However, the contact lenses can cause some discomfort at the very least, and possibly lead to infections and permanent vision loss."
Currently, the U.S. Food and Drug Administration has approved only one OKL, made with material that allows oxygen transmission to the cornea, for nighttime wear.
Study author Dennis S.C. Lam, FRCS, FRCOphth, chairman and professor Department of Ophthalmology and Visual Sciences at the Chinese University of Hong Kong, said, "The general public must be aware that overnight OKL wear is non physiological. It may be associated with very serious and visually significant complications."
"The safety of orthokeratology needs to be carefully evaluated, especially in children," the study states in its conclusion. "The issues of hygiene, risks of corneal trauma, infection and long-term effects of contact lenses on endothelial functions need to be further assessed." The study went on to say, "Parents and children must be educated on the symptoms of contact lens-related infections and the need for immediate ophthalmic consultation."
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. For more information about eye health care, visit the Academys partner Web site at www.medem.com/eyemd. To find an Eye M.D. in your area, visit the Academys Web site at http://www.aao.org.
Media Relations | EurekAlert!
Unique brain 'fingerprint' can predict drug effectiveness
11.07.2018 | McGill University
Direct conversion of non-neuronal cells into nerve cells
03.07.2018 | Universitätsmedizin der Johannes Gutenberg-Universität Mainz
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
17.07.2018 | Information Technology
17.07.2018 | Materials Sciences
17.07.2018 | Power and Electrical Engineering