Reproducibility of LipiView Ocular Surface Interferometer (LipiView) for Measuring Tear Lipid Layer Thickness

Dry eye clinical research is limited to follow up of disease progression. While a large catalogue of tests, such as corneal staining grading, tear break up time (TBUT) and Schirmer's test, is available, objective assessments demonstrate poor to moderate repeatability. Among these assessments, TBUT has the best repeatability while the Schirmer's test shows good repeatability for more severe forms of the disease.1 As such, currently, most research outcomes are based on subjective patient complaints rather than objective assessment of the condition. LipiView Ocular Surface Interferometer (LipiView) is a HSA-approved imaging device that has the ability to assess optical interference pattern produced by light reflected off the tear film in a safe and non-invasive manner.2 Software analysis of the image then measures the tear LLT, which is used to objectively quantify the diagnosis of lipid-deficient dry eye. This current study aims to investigative the inter and intra-examiner reproducibility of measuring tear lipid layer thickness (LLT) with LipiView, which is used in our current clinical setting. LipiView has not been evaluated on its reproducibility of measuring tear lipid layer thickness. The study will also assess for correlation between the magnitude of tear LLT and the inter and intra-examiner reproducibility of LipiView. Once this method is found to be repeatable, this can be used in future clinical settings and trials as an additional tool to investigate dry eye treatments.