The primary reason pupils enlarge is to allow more light into a person's eye when in a dark room or area, according to Healthgrades. When people go in for certain eye exams, the eye doctor uses drops to dilate or enlarge the pupils to examine the eyes better.
Cough and cold and decongestant medicines often cause a person's pupils to enlarge, according to Healthgrades. Cocaine and marijuana also cause pupil enlargement; however, the enlargement caused by drugs typically goes away after the effects dissipate. Health conditions, such as a stroke or tumor, can cause enlargement. Unlike a drug-induced enlargement, these medical triggers may impact only one pupil.Learn More
Adjustments to vision, such as blurry vision, can occur right after cataract surgery, states Mayo Clinic. Vision usually begins to improve a few days following surgery. Patients usually have a follow-up appointment within 24 to 48 hours after cataract surgery and a month later to monitor healing.Full Answer >
In order to be considered legally blind, a person must have a score of no better than 20/200 on a vision test while wearing corrective lenses, according to WebMD. The test may also be administered with a restricted field of vision, but the results must be the same.Full Answer >
The Farnsworth Lantern Test is a test of color vision. Test takers must identify the colors of two lights that may be any combination of red, green or white.Full Answer >
There are manufacturers who make decorative red contact lenses that can be worn with costumes; however, the lenses sold must be FDA approved. It is illegal for contact lens manufacturers to sell colored lenses to consumers that are non-prescription and unregulated.Full Answer >