Brief Answer:
Read below.

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

Issues of tinnitus (hearing sounds) and vertigo can be due to many different causes, most of them related to the ear as our ears are not only responsible of hearing function but also very much involved in balance, so issues of middle and inner ears and the nerves connecting ears to the brain can manifest with tinnitus and vertigo.

Some common issues can be infections, exposure to loud noises, exposure to toxins such as lead or some medications. Some types of vascular malformations may manifest with tinnitus but it is usually constant and pulsatile (like hearing heartbeat). Acoustic nerve tumors are another cause but the symptoms are usually on only one side and are persistent and progressively increasing, do not come and go.

Apart from these local issues at times other issues may be involved such as thyroid dysfunction, anemia, vitamin B12 deficiency. Anxiety is a common cause as well.

As you can see the list is long so I will stop before risking to confuse you. What is important is to identify patterns which may sound the alarm bells, such as progressively increasing symptoms, pulsation character, headache, other neurological manifestations such as weakness of facial muscles or limbs on one side, speech articulating difficulties, coordination and balance issues, eye movement issues etc. It is in that case that particular care is needed and head imaging with MRI may be considered.

In your case I do not see any such worrying symptoms, the fact that the symptoms have been present for years, coming and going is enough to ease your worries, often this pattern is more related to stress and anxiety. Some routine blood tests to check for anemia, thyroid function, vitamin B12 levels etc (if you haven't already had them during this time) as well as an ear exam is recommended, but on a non urgent basis.

I remain at your disposal for other questions.

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