I am sorry that your question was unanswered for long.
The causes of dizziness according to the decreasing incidence are;
1) Benign paroxysmal positional vertigo (BPPV) 20%
2) Vestibular 15%
3) Migraine and motion sensitivity 15%
4) Anxiety and depression 10%
5) Meniere's disease 7%
6) Cerebellar disease 6%
7) Transient ischemic attacks 5%
8) Orthostatic hypotension 4%
Since your MRI and CT scan has not revealed anything, your physician may consider MRA (magnetic resonance arteriography), which helps in detecting vascular lesions. MRI with gadolinium enhancement is particularly useful in detecting smaller intracanalicular tumors such as acoustic neuromas. It is also recommended for identifying sclerotic and demyelinating white matter lesions characteristic of multiple sclerosis. So that can be another investigation considered by your doctor. BPPV is another possibility to be considered as it is the commonest cause for dizziness. BPPV is treated by various exercises like Epley maneuver, Brandt-Daroff exercises, Semont maneuver etc. There are online videos, on which you can learn these exercises and try meanwhile, you are investigated;
Chronic dizziness associated with the floating, rocking and light headedness and is induced by eye movements (head being still) should be also investigated or correlated to anxiety and depression, if all the medical imaging, blood work and examination is negative. If you are on any medications, their side effects also should be ruled out for lightheadedness, as drugs are quite a common cause for this symptom. Dizziness may be provoked by only certain movements, such as standing up after lying down for at least 10 minutes in orthostatic hypotension, or may occur after vertical or oblique head movements, such as lying down, turning over in bed, or sitting up in benign paroxysmal positional vertigo (BPPV). Simply moving the eyes with the head stationary causes dizziness and there is no eye movement disorder (ocular misalignment or an internuclear ophthalmoparesis), then dizziness is likely to be the result of anxiety. When dizziness occurs without provocation (spontaneous) and is vestibular (ear disorder) in origin, it frequently is exacerbated by head movements.
The dizziness with neck movements and heaviness on back of head can be explained on the basis of what we term as cervical spondylosis. This predisposes to lightheadedness or vertigo which can originate from a condition called as cervicogenic vertigo. This is because of the degenerative changes in the cervical spine and hardening of the carotid arteries (neck vessels which supply blood to brain). Read about the cervicogenic vertigo;
You should consult either a physical therapist or MD in physical medicine and rehabilitation. They would teach you specific exercises for neck and shoulder girdle and may consider traction to the neck. People who work long hours on computer are predisposed to it.
Internal ear disease vertigo is termed true vertigo in which one feels rotational movement of self or the surroundings. The false vertigo or nonvertigo has feeling of light-headedness, unsteadiness, motion intolerance, imbalance, etc. Often, dizziness can be a multisensory disorder due to any combination of peripheral neuropathy, visual impairment, and musculoskeletal disease. Many patients who have thyroid dysfunction can present with dizziness as an initial complaint. In individuals who have migraine, dizziness and vertigo can occur as part of the aura or separately. Spells usually last approximately an hour but can last several hours or days in patients who have severe disease. Most patients who have migraines have a long history of recurring symptoms. So that too should be assessed as a cause if you have a history of migraine.
Your primary care physician should refer your to a neurologist, cardiologist and ENT specialist (a second opinion is essential as your first ENT specialist is unable to pin point the cause) for evaluation as the causes can be divided on the system also, which is involved;
1) Inner ear or internal ear disease vestibular disorders or internal ear disease
2) Central nervous system like migraine
3) Cardiovascular, or
4) Systemic diseases like thyroid disorder.
Please feel free for your follow up questions.
I would be happy to assist you further, if you need any more information.
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