Left untreated Dry Eye can lead to blurred vision because the cornea may be damaged.
Some treatments can also lead to blurred vision because they cover the cornea with a layer of material that changes the focal length of the cornea. These include: lubricating drops; lubricating ointments; other drops and ointments; meibum that is secreted after warm compresses; or meibum that is secreted when the meibomian glands are expressed. When topical treatments cause blurred vision, the blurring usually passes when the treatment has stopped or the material has cleared from the cornea.
When pressure is applied to the corneas, during warm compresses, lid massage, when using lid scrubs, or when blotting tears, the cornea is temporarily bent and the result may be blurred vision. Do not to push hard on the eye balls for any reason when the eyes are closed to avoid blurring vision or damaging corneas.
Reference
The Dry Eye Disease Activity Log Study
Jayant V. Iyer, Sze-Yee Lee, Louis Tong
The Scientific World Journal
ScientificWorldJournal. 2012; 2012: 589875. Published online 2012 Oct 24. doi: 10.1100/2012/589875
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