Mild vision impairment found in highly myopic, healthy eyes
SEATTLE – Researchers found mild visual impairment in a significant percentage of patients with high myopia but no ocular pathology.
Monica Jong, PhD, BOptom, and colleagues reported here at the Association for Research in Vision and Ophthalmology meeting that they evaluated 646 subjects with high myopia but no pathology who were part of the Zhongsham Ophthalmic Centre-Brien Holden Vision Institute high myopia study in Guangzhou, China. Patients were between 7 and 63 years old with myopia of 6 D or worse in both eyes.
The researchers classified no vision impairment as 20/20 or better, mild as 20/20 to 20/60, moderate as 20/60 to 20/200 and severe as 20/200 to 20/400. They found that 63.3% had no vision impairment, 31.5% had mild, 1.2% had moderate, and 0.3% had severe.
“Visual impairment was related to increased refractive error and increased axial length,” Jong told Primary Care Optometry News. “With increased age there was increased visual impairment.”
Mild vision impairment was most commonly seen in those 41 years and older, according to the poster.
“We think that high-powered spectacles reduce the image size, and when the eye elongates, it stretches the eye and increases the spaces between photoreceptors,” Jong speculated. “Some of these patients may have undetected conditions like retinoschisis. “Overall, doctors should consider contact lens correction to improve best-corrected visual acuity in high myopes,” she added. “Future work will involve using adaptive optics to analyze photoreceptors.” – by Nancy Hemphill, ELS, FAAO
Jong M, et al. Vision impairment in highly myopic eyes without ocular pathology: The ZOC-BHVI High Myopia Study. Presented at: Association for Research in Vision and Ophthalmology meeting; May 1-5, 2016; Seattle.
Disclosure: Jong reported no relevant financial disclosures.
Editor's note: The first version of this story published on May 4, inaccurately stated that mild vision impairment was most commonly seen in those 20 years and younger, and was corrected on May 5.