50 Shades of Migraine

May 1, 2013
50 Shades of Migraine

Migraine Disorder is a new, descriptive term intended to include a currently disparate group of medical symptoms and conditions which might have a common pathophysiologic etiology. The unifying idea is that there are a number of complaints that are related to a malfunction, or hypersensitivity of the sensory and autonomic nervous system in these people. Furthermore, there appears to be a common genetic influence in this neuropathy. The link to migraine is strengthened in patients who have a history of one or more of the three most common symptoms of a migraineur: recurrent intense headaches, odd transient ocular symptoms (random white spots, zigzags, loss of vision, or blurring and motion intolerance (car sickness). In each of these conditions a person with this defective nervous system have a hypersensitive pain, visual or balance system. Another common theme among people with a migraine disorders is that hormonal fluctuations aggravate the defective nervous system.

There has been evidence the presumed neuropathologic defect might be in an abnormal amplification of the neurotransmitter communication system between neurons. This concept is reinforced by the effectiveness of medications, such as nortriptyline (which affects the neurotransmitter serotonin), Effexor (which affects serotonin and norepinephrine) and topiramate (its metabolic action is not fully understood, but this molecule works on 4 different aspects of cellular function). And, somehow, estrogen, and perhaps other hormones, further alter this neural function. This is supported by the high incidence of migraine-related disorders in women and the fluctuations that occur with the menstrual cycle, pregnancy or menopause. But there is much to learn about this biochemical process.

This theoretic model for migraine equivalent neuropathy may offer a neurologic explanation for many head and neck symptoms. This might include several forms of sleep disturbance (central sleep apnea and restless leg syndrome) and why these patients often complain of excessive fatigue. People with a migraine equivalent neuropathy also complain of “brain fog” or reduced cognitive function (short term memory loss, inability to recall words – apraxia or expressive aphasia, unable to multi-task).

This disorder might explain the odd sensation of feeling relatively large or small (Alice in Wonderland syndrome). A similar neuropathy might explain a number of symptoms related to the ear: difficulty hearing or understanding speech (central auditory processing disorder), sound sensitivity (hyperacusis), tinnitus, a foreign body sensation in the ear, ear pressure, blocked sensation, or feeling that the ear is wet or full of fluid or ear pain. There is already recognition of migraine-related vestibulopathy and possibly mal de debarquement (persistent sensation of movement when standing still), but there are probably more common forms of migraine equivalent neuropathy which are easily confused with benign positional vertigo, Meniere’s disease, ataxia (intermittent losses of balance).

Other migraine-related phenomena likely include skin and scalp sensitivity to light touch (cutaneous allodynia) – such as glasses on the nose or pain when cleaning the ear or wearing a hearing aid and smelling foul odors that others do not detect (phantosmia), excessive sensitivity to odors (osmophobia) and, perhaps, the burning tongue phenomenon. Migraine disorders include light sensitivity and transient loss of vision or double vision.

One of the more common and misdiagnosed symptoms is the chronic or recurrent feeling of pressure across one’s cheeks, between or behind the eyes or across the forehead, coupled with nasal congestion and a runny nose which is interpreted by a person as sinusitis. This hypersensitivity of the trigeminal and autonomic nerves may also present as dental pain. Other hypersensitive nerves can cause a prolonged dry cough or throat pain and sensitivity.

The spectrum of migraine disorders may include mood disorders. It is not likely a coincidence that many migraneurs also suffer from depression and anxiety. Nor is a coincidence that antidepressant medicines in lower doses are often effective in suppressing migraine equivalent disorders. This neural misfiring has also been associated with central nervous system malfunctions of body heat regulation, the autonomic system and allergies. It is the hyperactive autonomic system that results in patients with stuffy, runny noses that mimic sinus infections and allergies.

Beyond the head and neck region, this migraine phenomenon may explain cyclic vomiting syndrome, abdominal migraines and some forms of irritable bowel syndrome. Other possible migraine conditions include fibromyalgia, benign paroxysmal torticollis and excessive hot flashes (disturbance of central nervous system temperature control).