I experienced bright, wavy lines in my vision for about 30 minutes. What was that?

You probably experienced an ophthalmic or ocular migraine, that is, a migraine not accompanied by a headache. Usually, one sees flashes of lights, colored lights, or zigzag lines that extend to one side of vision for about 10-30 minutes. An ophthalmic migraine is also referred to as kaleidoscope vision, where images are broken up and seem shiny or brightly colored, like those in a kaleidoscope. While an ophthalmic migraine may not be serious, it is advisable to consult your eye doctor because sometimes, it may be a symptom of more serious conditions like severe brain injury, stroke, or retinal damage.