A new look at tears

Dry eye disease (DED) is a complex ocular surface condition that results in discomfort, fluctuations in vision, contact lens intolerance and ocular surface damage.^1-4 The aetiology of DED is multifactorial and diagnosis requires evaluation of the tear film, eyelids and consideration of associated systemic conditions and medications.^3,5-9

The tear film is broadly composed of three complex layers – a superficial lipid layer, a thicker muco-aqueous gel in the middle and a multi-layer mucin that integrates with the ocular surface.^10-12 Irregularities of the tear film can cause visual blur and ocular discomfort.⁴

Improving the tear film, and the surface lipid layer specifically, can reduce symptoms, improve optical quality and lead to better patient comfort, satisfaction and overall perception of wellbeing.^13-16 Providing new innovative methods for practitioners to evaluate the quality and quantity of the tear film is important, particularly as more pharmacological therapies come to market that target DED.