P you might possibly offer definitions of key terms, although it is often a good idea to save this until you use these words in the essay and you can then offer definitions when they become relevant to the reader rather than hitting them with all of the definitions in a big, boring, confusing mass right at the start.
Thygeson's superficial punctate keratopathy (TSPK; also Thygeson Superficial Punctate Keratitis) is a disease of the eyes. The causes of TSPK are not currently known, but details of the disease were first published in the Journal of the American Medical Association in 1950 by Phillips Thygeson-after whom it is named. patient with TSPK may complain of blurred vision, dry eyes, a sensation of having a foreign body stuck in the eye, photophobia (sensitivity to bright light), burning sensations and watery eyes.
From Wikipedia, the free encyclopedia. A punctal plug, also known as tear duct plug or lacrimal plug, is a small medical device that is inserted into the tear duct (puncta) of an eye to block the duct. This prevents the drainage of liquid from the eye. They are used to treat dry eye. Artificial tears are usually still required after punctal plug insertion.