PORTLAND, Ore. – Monday’s spectacular total solar eclipse was viewed by millions throughout the state of Oregon.

During past eclipses, people who have looked at the sun during the eclipse without proper glasses experienced lifelong eye damage that resulted in impaired vision.

More: Man visually impaired by sun during eclipse warns of viewing dangers

Pacific University says solar retinopathy, damage to the eye’s retinal tissue, can occur after viewing the sun unfiltered for just a few seconds, even if the sun is almost but not completely eclipsed, as it was in most of Oregon on Monday.

“Often times, there are no immediate symptoms or pain associated with retinal damage because retinas do not have pain receptors,” said Dr. Lorne Yudcovitch. “Changes to vision or light sensitivity may not be noticeable until the following day or longer.”

He said if your eyes feel any discomfort, such as pain or sensitivity to light, in the following days, you should get them checked out. Yudcovitch said not all damage is permanent but it’s important to get treatment as soon as possible.

Watch: Total solar eclipse totality