QST for Corneal Nerve Function

The cornea (window in the front of your eye) is made up of many nerves with important regions that allow you to feel sensations like, heat, cold, pressure and vibration. It is well known that many ocular surface disorders, such as dry eye disease (DED), neurotrophic keratitis and post-herpetic neuralgia, affect corneal nerve structure, which can be detected by a special type of eye imaging called ‘In-vivo Confocal Microscopy (IVCM)’. However, the relationship between eye symptoms, signs and abnormal corneal nerve functions are not yet well understood. The quantitative sensory motor test (QST) is a non-invasive method which evaluates nerve function with different stimuli such as cold, heat and vibration. Therefore, people with different corneal conditions who undergo QST may show varying pain responses to each sensation, and may characterize their pain in unique ways. This goal of this study is to find out which types of stimuli have the most impact on ocular discomfort among those with different types of corneal conditions, and compare QST results between ocular surface patients and those without any ocular surface conditions. Most procedures are standard of care which means they are typically performed during a routine eye exam and therefore during your routine clinical visit.