Brief Answer:
If there is no headache Aura migraine is unlikely

Detailed Answer:
Hello
Thanks for asking on this platform

I can understand your concern.As said by your previous doctors most of the time floaters are benign(not serious)condition due to small undissolved particle in the inner vitreous part of eye.
I would like to know if it is associated with headache?
Is there any history of trauma in past?
Is this associated with flashes of light,transient blackening of visual field or any visual defect?
For how long it persists?
Is there any aggravating or relieving factor?

Most of the symptoms occur in bright light,when looking at white paper or towards sky.I wont get overly worried If answer of all the questions are no.

There can be one condition like Ocular migraine or aura migraine.
The difference between these two is that in aura migraine along with floaters there would be headache as well.
In ocular migraine there will be no headache and there is sudden appearance of floaters in visual field for about 30 minutes(irrespective of the light or other condition)and usually subsides on its own.
The aura migraine needs treatment but ocular migraines does not need any treatment.
As per your description to me it appears to be benign floaters(as not associated with headache) which are normal in any age and does not need investigation like MRI.

Thanks and regards

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