Hi. I'm online and happy to answer your question today.
You don't have a brain tumor.
What your optometrist is talking about is a posterior vitreous detachment.
You are likely experiencing a PVD or posterior vitreous detachment, a common event that happens in many people. You have a thick gel material in the middle of your eyes called the vitreous. Over time as it liquefies, this gel material collapses on itself, forms little clumps that you can see as dots, lines or bugs. As these clumps form the vitreous pulls away from the wall of the eye. In the process it can stimulate the retina -- causing the flashes that you may see. It is recommended that you see your ophthalmologist to look at the retina to make sure there are no problems such as a retinal hole or tear. In most cases, there are no problems, but this exam is precautionary and allows for preventative treatment of any lesions that are found. If you notice a sudden increase in floaters, flashes of light (like a lightning storm), or a shadow/veil in the periphery of your vision, this can be worrisome for a retinal detachment. You would need to contact your ophthalmologist promptly in that case.
What can you do about them? Well, floaters don't go away, and they don't really get worse. Over time they tend to "sink" out of your central vision and you brain "filters" them out so you don't notice them so much anymore. They almost never cause significant visual problems except, of course, if they cause a secondary retinal detachment as discussed above.
I guess you are offline......
Now, you mentioned migraines. Since your not online for me to ask you more details let me just tell you a little about the spots/zigzag lines you can see with a migraine. Here is is a handout on this topic:
A typical migraine headache starts with shimmering lights, often times they surround a blurry area or have dots or jaggedly lines associated with them. They tend to progressively increase in intensity and sometimes march across the visual field causing difficulty with reading. Many times this is then accompanied by nausea, irritability, sensitivity to bright lights and/or loud noises. After the onset of the lights (called scintillating scotomas), the headache typically starts and the light show tends to progressively go away.
Many people can have this migraine phenomenon without the headache; it is called an acephalgic migraine. Some people even start having these late in life, or may have had a few much earlier in life that behaved differently and haven't had any for decades and then begin to have them; this is not uncommon. A family history of migraines is often present as well.
This is nothing to worry about. It is not a sign of a more serious underlying condition, brain tumor or anything like that. If the episodes become so frequent that they are bothersome there are medicines that can be used to decrease their frequency or stop an episode once it has started.
Once again, no brain tumor :o)
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