Headache is considered primary when a disease or other medical conditions does not cause the headache. Most primary headaches fall into three main types described as tension, migraine, and cluster headaches. Tension headache is the most common primary headache and accounts for 90% of all headaches. Migraines are the second most frequently occurring primary headaches. Migraine headache is also known as a Neurovascular Headache.
Migraines—Severe and Prolonged Pain
Migraines are identified as primary headaches because they do not stem from a larger issue, such as a disease or disorder. Migraines may cause pain on one side of the head or radiate all over.
Migraines are usually severe with regard to pain intensity and may prevent sufferers from engaging in everyday activities. Individuals suffering from migraines usually experience pain for a few hours at a time and may even experience pain for several days. Migraines are classified into two main categories:
1. Migraine with aura
Individuals experiencing migraine with aura may see stars, lights or blurry lines or have a temporary blind spot before the headache hits, whereas those encountering migraine without aura experience two or more criteria, including nausea, vomiting or sensitivity to light, sound or smell.
While an official examination and consultation with a doctor is needed to rule out other possible causes and determine what type of migraine you are suffering from, migraines are distinguished from headaches by several common symptoms. Migraine sufferers often experience throbbing or pulsating pain; sensitivity to light, sounds or smells; vision impairments; nausea and vomiting.
Description of Migranous Headache
- Intense throbbing or a pulsating headache
- Headache may last for hours to days
- Patient prefers to lie in a dark, quiet place.
- Headache is triggered by exercise and strenuous activities.
- Headache follows- nausea, vomiting
- Headache preceded by aura
- During headache- increased sensitivity to light and sound.
Sensory Symptoms: Second most common aura, occurs in about one-third of patients with migraine.
Numbness, tingling or paresthesia
- Distribution - Often face and hand.
- Brain Stem Dysfunction - Rare, presented with hemi motor weakness dysphasia, and incoordination
- Ranges in level of consciousness- Rare
Following Are The Three Major Types Of Migraine-
- Migraine Headache with Aura
- Migraine Headache without Aura
- Migrainous Aura Without Headache
Symptoms and causes vary among migraine sufferers. However, brain scans illustrate a person who suffers from regular migraines has a different brain biochemistry than those who do not. Brain imaging reveals those who experience migraines may be feeling the effects of an overactive brain. In the mid-1990s a number of people reported improvement in headaches in patients receiving botulinum toxin for other reasons. Well-conducted clinical trials of botulinum toxin in various types of headache followed, but the results were disappointing, with no difference over placebo being found in tension-type headache, episodic migraine, and undifferentiated chronic headache. Detailed analysis of the results suggested, however, that there might be a subgroup of patients with chronic migraine who could benefit, and further trials were undertaken.
Botox® in chronic migraine: the PREEMPT trials
Two Phase 3 Research Evaluating Migraine Prophylaxis Therapy (PREEMPT) trials recruited 1384 patients with chronic migraine, and randomised them to treatment with Botox® or placebo. These patients were suffering on average 20 days of headache each month, of which 18 were moderate or severe. After 12 months, 70% of those treated had ≤50% the number of headaches that they had done originally. Botox® was well-tolerated, the commonest side effects being neck pain (6.7%), muscular weakness (5.5%), and drooping of the eyelid (3.3%). No serious irreversible side effects have ever been reported in trials of Botox® in headache.
How does botulinum toxin work in chronic migraine?
The simple answer is that we don’t know fully. A recent US study by Rami Burstein et al using animal models suggested that botulinum toxin inhibits pain in chronic migraine by reducing the expression of certain pain pathways involving nerve cells in the trigeminovascular system. The trigeminovascular system is a sensory pathway thought to play a key role in the headache phase of a migraine attack.
Is Botox® right for me?
Only patients with chronic migraine are eligible for treatment with Botox®. Chronic migraine is defined as headaches occurring on 15 or more days each month, at least half of which have migrainous features. There are, however, other treatments available to patients with chronic migraine, and it is important that patients have an informed discussion of their headaches and the options for treatment with a practitioner experienced in the diagnosis and management of headaches before a decision to use Botox® is taken.
Who can inject Botox® for chronic migraine?
At present the use of Botox® is restricted to a few specialist headache centres, but as time goes on there should be increasing numbers of trained injectors available. In all cases, however, you should ensure that the person injecting has received appropriate training, both in the diagnosis and management of chronic migraine. Dr. Treacy has a long experience with Botox and Migraine and has lectured on this subject since 2003.