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.
The study authors said they could not determine whether or not the contact lenses worn by the patients were designed for orthokeratology. They also did not know if the lenses were made of materials designed for high oxygen transmission or whether the lenses had been properly fitted for the patients. Factors that may have contributed to the increased risk of corneal ulcers and infection included: