When Two-Colour Dark Adaptometry is More Sensitive than Full-Field Electroretinogram in Detecting Vitamin A Deficiency – A Case Report

Introduction

Vitamin A deficiency is usually associated with permanent visual symptoms such as night blindness, concentric loss of visual field, and xanthopsia. Full-field electroretinogram (ERG) usually reveals rod > cone dysfunction. Whereas malnutrition is the leading cause of hypovitaminosis A in poorly developed countries, malabsorption is responsible for most cases encountered in the Western world [1], [2].

We report a patient with fluctuating visual symptoms suggestive of vitamin A deficiency retinal dysfunction in whom an ERG was normal but dark adaptometry was markedly abnormal.

Publication History

Received: 30 August 2021

Accepted: 30 December 2021

Article published online:
23 March 2022

• References

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