Headaches
Tension and Migraine Headaches
General
Fifty-nine percent of the adult population in Canada report some form of headache. Thirty percent suffer
from tension-type headaches, and 17% suffer from some form of migraine. Tension type headaches are
not usually disabling but up to three quarters of migraine headaches are sufficiently severe to limit
regular activities. Most migraineurs have attacks that last 12 to 24 hours.
Migraine can be divided into two categories, migraine with aura (classical migraine) and migraine
without aura (common migraine). The aura may be preceded by a prodrome of mood changes which may
interfere with routine activities. The aura itself usually lasts about 20 minutes and immediately
precedes the onset of the headache. The cause of the aura has been debated but may be secondary to
metabolic and/or electrical changes which may possibly be accompanied by ischemic change in the
cerebral cortex. The head pain itself is thought to be related to a sterile inflammatory response around
blood vessels in the face and scalp and the intracranial vessels of the coverings of the brain. This
inflammatory response is mediated through vasoactive peptides which cause dilatation, edema
and inflammation around the vessels which are innervated by a branch of the trigeminal nerve
(trigeminal-vascular complex).
Migraine tends to occur at times of let-down from stress, after fasting, and after missing sleep. Flashing
lights and bright reflected light may also trigger acute attacks.
Aeromedical Status
Migraine without aura – Most applicants will be considered fit.
Migraine with Aura
Group 1.
Applicants with auras which:
- would not interfere with flight safety and,
- have been consistently the same aura over several years, can generally be considered
for medical certification.
Group 2.
Applicants with auras that:
- are of slow onset; and
- occur infrequently ie. once every several months; and,
- are not associated with cognitive impairment, but may cause minor sensory difficulty that does not impair performance;
and
- have been consistently the same over several years.
Group 3.
Migraineurs who have significant auras which can interfere with flight safety and who do not fit
into the group 2, (ie, too fast onset, too frequent, cognitive impairment, unclear history,) should
generally be considered unfit for all categories. They may be considered for restricted medical
certification if after 3 years they fit in group 2.
Cluster Headaches
Cluster headaches occur only in 0.1% of the population and are generally episodic and 80% of the
cases occur in men. The headaches usually last about one hour and 50% of the cases begin during sleep.
They recur in bouts lasting six weeks or more, during which time acute attacks occur one to four times per
24 hours. Once the bout is ended, however, the sufferers are usually entirely headache free for
months or years. The individual attacks are extremely intense, localized around one eye and associated with
nasal congestion and lacrimation which may impair vision. They are virtually always incapacitating. The
applicants should be considered unfit during a bout of cluster headache but during the interval bouts, they
may be considered fit. Between bouts, the applicants do not need to take any medication, but in chronic
cluster headache where the bout extends beyond six weeks, medication which might impair functioning
may be required.
Trigeminal Neuralgia
Trigeminal Neuralgia causes piercing, electric shocklike facial pains which have a high frequency of
recurrence. Many episodes may occur in a single day. In older age groups these are often secondary to a
loop of blood vessels pressing against the trigeminal nerve: in the young they may be secondary to
multiple sclerosis. Individuals suffering from trigeminal neuralgia are unfit but if they go into
remission may be considered for medical certification.
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