Age, degree of myopia, axial elongation associated with myopic maculopathy
Researchers found that the development of myopic maculopathy in high myopia is associated with older age, higher myopic spherical equivalence and increased axial elongation.
Additionally, children between the ages of 7 and 11 years with myopia are at higher risk of developing diffuse atrophy or more severe lesions.
Two of the study authors, Xinxing Guo, MD, PhD, of the Wilmer Eye Institute, Baltimore, and Mingguang He, MD, PhD, Centre for Eye Research Australia, University of Melbourne, collaboratively corresponded with Primary Care Optometry News about their findings.
“Eight out of 10 Chinese high school graduates are myopic, and there is an increasing trend of high myopia (worse than -6.00 D) epidemic. It is projected that by 2050, 50% of the world population will be myopic, and 10% [will be] highly myopic,” Guo and He wrote. “Myopic maculopathy, as retinal damage secondary to high myopia, does not develop in all highly myopic eyes.
“What is the distribution and spectrum of myopic maculopathy in highly myopic eyes?” they continued. “Who is at higher risk of developing myopic maculopathy? Understanding the disease distribution and risk factors has tremendous public health implications given the global myopia boom.”
Using patients initially recruited for the Zhongshan Ophthalmic Center-Brien Holden Vision Institute high myopia cohort study, 890 highly myopes between 7 and 70 years old were enrolled, according to the study. Six patients presented with coexisting retinal pathology in their right eyes and were excluded from the study.
Study patients had spherical refraction of 6.00 D or worse in both eyes and underwent an ophthalmic examination. Each patient was assigned to one of five categories according to the International Photographic Classification and Grading System: category 0, no myopic retinal lesions; category 1, tessellated fundus only; category 2, diffuse chorioretinal atrophy; category 3, patchy chorioretinal atrophy; category 4, macular atrophy. Patients with evidence of category 2 had been considered to have clinically significant myopic maculopathy (CSMM).
“People 40 years and older, or with higher degree of myopia, for example greater than -8.00 D, are more likely to have clinically meaningful myopic maculopathy, ie, diffuse chorioretinal maculopathy or severe,” Guo and He wrote. “The other interesting finding is the higher proportion of myopic maculopathy in very young children (7 to 11 years) compared to adolescents (12 to 18 years). These findings indicate that early onset high myopia could be genetic in origin and carries greater risk of developing retinal lesions.”
Xiao and colleagues acknowledged that the results of study could not be applied to high myopia cases in other races, due to the entire cohort being Chinese in both race and nationality.
“The current study is the baseline report on a large-scale high myopia cohort,” Guo and He wrote. “The participants will be followed for at least 10 years and re-examined every 2 years. We hope to further exploit this cohort to identify modifiable risk factors, understand the causal links between risk factors and long-term myopic maculopathy outcomes, and to explore other associations.
“We are open for collaboration on the high myopia research work, and we hope future studies can take advantage of the big data era with real-world digital health information and international disease registries,” they continued. “We have been collecting extensive data, such as OCT angiography, swept source OCT, fundus fluorescein angiography, indocyanine green [angiography] and other imaging for this group of patients; we are looking for retinal specialists who are interested in high myopia research to reach out to us.” – by Scott Buzby
Disclosure: None of the authors reported relevant financial disclosures.