Refraction Topography (RT)​

--- A New Technology Makes Relative Peripheral Refractive Error Visual and Measurable

Why is it essential to assess peripheral refraction?

The global population's myopia problem is becoming increasingly severe.

The World Vision Report released by the World Health Organization (WHO) in 2019 revealed that 2.6 billion people worldwide are affected by myopia, including 312 million adolescents under the age of 19. By 2030, the global number of individuals with myopia is expected to rise to 3.4 billion.

The latest research indicates that myopia affects nearly one-third of children and adolescents globally. It is projected that by 2050, over 740 million children and adolescents worldwide will be affected by myopia*.

* Liang J, Pu Y, Chen J, et al. Global prevalence, trend and projection of myopia in children and adolescents from 1990 to 2050: a comprehensive systematic review and meta-analysis. British Journal of Ophthalmology 2025;109:362-371.

How can MRT effectively identify peripheral defocus?

Refraction topography (RT) is a newly developed imaging technique that can quantify retinal refraction across a 53° posterior pole field. It uses multispectral illumination to acquire fundus images, and then, proprietary algorithms computationally separate the refractive data from them at each retinal position, resulting in the generation of high-resolution dioptric topographic maps.

What critical clinical challenges can RT resolve?

Myopia Intervention: Early assessment before axial elongation.

Myopia Evaluation: Pre-assess and validate contact and ortho-k lens fitting.

Myopia Management Strategies:  Same degrees, different MRT patterns—should the treatment be the same?

Relative peripheral refractive error (RPRE) is one of the important factors contributing to myopia

Relative peripheral hyperopic defocus is closely associated with myopia onset and axial elongation. Importantly, changes in defocus patterns occur before axial length changes, providing an earlier indicator of treatment effectiveness. 

Orthokeratology has gained popularity, alongside defocus contact and spectacle lenses. Recent research has renewed interest in these options for correcting peripheral hyperopic defocus and reducing signals that lead to eye elongation.