Advances in Screening for Amblyopia

Salal Khan, M.Optom

Student, Galgotias University, U.P, India

 

Introduction

Amblyopia is the most common cause of monocular visual impairment in children, with a prevalence of 2–3%. Not only is one eye’s visual acuity reduced, but also binocular vision, fellow eye deficiencies, eye-hand coordination, reading, and self-perception may all be affected.^(1-3)

There are emerging technologies that show promise for accessible, early, and accurate amblyopia detection rather than risk factors during preschool vision screening, such as:

1. Retinal birefringence,
2. Optokinetic nystagmus visual acuity screening, and
3. Artificial intelligence

Binocular Retinal Birefringence (RBF) Screening

RBF scanning is a new technique that has been created to identify strabismus and amblyopia. RBF scanning makes use of the radially organised Henle fibres and distinctive architecture of the human fovea.^(4-5)

Optokinetic Nystagmus VA Screening

• While the high contrast black and white bars of the optokinetic nystagmus (OKN) drum used in the clinic are useful in determining whether a gross vision response is present, there is no obvious relationship with visual acuity in this test. Instead, novel vanishing optotypes are used to induce involuntary OKN eye movements.^(6-7)
• On the other hand, the vanishing optotypes used in the Objective Acuity Vision Screener are highly correlated with ETDRS visual acuity in adults.⁽⁸⁾

 Artificial Intelligence and Screening

• Researchers are just now starting to look into the promising potential of artificial intelligence (AI) to improve preschool vision screening.^(9-10)
• AI parameterized algorithms and heuristics can optimize the processing of sensory, image, and eye movement data and can tailor the progression of test stimuli to each child’s performance to reduce test time. The overall objective is to develop the neural network models, compare them to a gold standard complete examination, and assess how well they diagnose strabismus and amblyopia.⁽¹¹⁾
• This method has demonstrated success in treating a range of adult medical disorders, including the early diagnosis of immune-related adverse events, the prognosis of cognitive loss, and the requirement for cataract surgery. If accurate, AI might offer a simple, accessible, low-cost, and low-manpower preschool vision screening method.^(12-13)

Conclusion

The development of new screening techniques that specifically target amblyopia rather than risk factors shows potential for more precise preschool screening. Together with recent developments in amblyopia screening, we anticipate better visual results for kids who have amblyopia.

Conflict of interest: Nil

 

References:

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