The Role of Biomarkers in Keratoconus Pathogenesis and Diagnosis

Keratoconus is an inflammatory disease of the cornea associated with corneal thinning, ectasia and biomechanical weakness. It can lead to significant visual disturbance in more advanced cases due to the associated irregular astigmatism and even corneal scarring. The diagnosis of keratoconus is made primarily based on it’s clinical features and corneal topography or tomography. A lot is now known about the multifactorial and polygenic nature of this condition with a variety of risk factors from the environment, inflammation, hormonal imbalance, oxidative stress, genetics, eye rubbing and allergy influencing it. Dysregulated corneal extracellular matrix remodelling is key to keratoconus pathogenesis. Advances in diagnosis and management have helped improve patient care from diagnosis and treatment point of view. However, there are still many lacunae in our understanding of the etiopathogenesis of this disease. Tears have been an important source of biomarkers for keratoconus along with corneal tissue and blood. The increased knowledge about the etiopathogenesis and diagnostic markers has also opened up options for targeted therapies. This chapter discusses the various biomarkers of keratoconus which are available to us and their role in understanding disease pathogenesis, diagnosis and treatment.