A VAS will be applied to evaluate dry eye symptoms as described by Schaumberg et al. (Schaumberg, Gulati et al. 2007). The scores will be recorded separately for frequency and severity of dry eye symptoms. The patient will be asked to check a point on a 100-mm line that corresponds to the degree of the symptom. The location of the mark made by the patient for each question will be measured in mm from the left hand side of the 100 mm line and recorded in mm. For the follow up visits, which measured the distance between the mark made by the patient and the central anchor, a negative value will be recorded if left of the anchor and a positive value if right of the anchor.