Brief Answer:
It can be seen in dizziness, vertigo, migraine...

Detailed Answer:
Hello
Welcome to Health care Magic.

I am Dr. Dadapeer K, an ophthalmologist and I will be answering your question.

I reviewed your history.
It seems from the history that your wife is having nausea associated seeing black spots in right eye.
Seeing black spots is commonly seen in dizziness, vertigo, primary headaches like migraine.....
Please provide me more details like
Whether blackouts or black spots were transient?
Does she have associated symptoms like headache, dizziness?

If it is only a single episode then no need to worry, if it is recurrent then needs evaluation.
Please provide me more details so that I can advice you more accurately.

Hope this is helpful to you.
Do write back to me for further questions.

Thank you

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