Brief Answer:
Read below

Detailed Answer:
I read your question carefully and I understand your concern.

It is unclear where your aneurysm was and also how was that managed, did you have it clipped? If yes that shouldn't be a worry. Anyway aneurysm usually cause symptoms when they rupture with very intense sudden headache, alteration of consciousness. Rarely in certain locations and when they are big do they cause other symptoms. So aneurysm shouldn't be related.

Mastoiditis can at times have intracranial complications such as cerebral venous thrombosis or brain abscess, but usually the clinical picture would have been much more serious, with other signs and symptoms, which wouldn't be transitory as your episode seemed to be. Similarly middle ear infection spread would have other persistent signs apart from the vertigo and wouldn't explain changes of vision.

So I do not think that those past issues are related.

One explanation could be a variant of migraine, ophthalmic migraine. Other explanations (more common and probable ones) could be dehydration, low blood pressure, or heart arrhythmia leading to transitory lack of perfusion in the brain. Also lack of perfusion could be related to narrowing of blood vessels supplying the posterior part of your brain due to atherosclerotic changes of the vessels or degenerative changes of the spine compressing them.

So if the episodes repeat in the absence of dehydration, a check up with blood pressure measurement, EKG, routine blood tests, ultrasound of neck vessels are recommended as well as physical exam for other signs you might have missed.

I remain at your disposal for further questions.

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