The headache of pseudotumor cerebri assumes a variety of forms. Most typical is a feeling of occipital pressure that is greatly worsened by lying down, but many patients have—in addition, or only—headaches of migraine or tension type. Indeed, some of them respond to medications such as propranolol and ergot compounds. None of the proposed mechanisms for pain in pseudotumor cerebri seems to be adequate as an explanation, particularly the idea that cerebral vessels are displaced or compressed, as neither has been demonstrated. It is worth noting that facial pain may also be a feature of the illness, albeit rare. Chapter 29 has a more complete description of the clinical features and treatment.
After successful treatment for pseudotumor, some patients have persistent headaches that have the flavor of migraine or tension headache.
These are commonly known to neurologists, as noted earlier in this chapter. They occur after lumbar punctures in approximately 5 percent of procedures. The headache is associated with the greatly reduced pressure of the CSF compartment and probably caused by vertical traction on cranial blood vessels. Neck pain may be a prominent, or the only, feature. Assuming the supine position almost immediately relieves the cranial pain and eliminates vomiting, but a blood-patch procedure may be required in persistent cases. In a limited number of cases, success has been obtained by the use of intravenous caffeine injections. The diagnosis is evident either from a lumbar puncture that demonstrates low or zero pressure or perhaps more definitely, by MRI with gadolinium, which has characteristic enhancement of the pachymeninges (dura). The condition and its treatment are discussed in Chaps. 2 and 29 “Lumbar Puncture Headache” and “Spontaneous Intracranial Hypotension.”
Menstrual (Catamenial) Migraine and Other Headaches Linked to the Hormonal Cycle
The relation of headache to a drop in estradiol levels during the late luteal phase of ovulation was mentioned in “Migraine” above. There it was also indicated that the mechanism is probably more complex. In practice, factors such as sleep deprivation are probably important in triggering perimenstrual headaches. Premenstrual headache, taking the form of migraine or a combined tension-migraine headache, usually responds to the administration of an NSAID begun 3 days before the anticipated onset of the menstrual period; oral sumatriptan (25 to 50 mg qid) and zolmitriptan (2.5 to 5 mg bid) are also equally effective. Manipulation of the hormonal cycle with danazol (a testosterone derivative) or estradiol has also been effective but is rarely necessary.
The management of migraine during pregnancy poses special problems because one wishes to restrict exposure of the fetus to medications. Beta-adrenergic compounds and tricyclic antidepressants may be used safely in the small proportion of women whose headaches persist or intensify during pregnancy. From a limited registry of patients who were given sumatriptan during pregnancy, and from several small trials summarized by Fox and colleagues, no teratogenic effects or adverse effects on pregnancy arose, but serotonin agonist drugs should be used advisedly until their safety is further confirmed. Ergots (DHE) are obviously interdicted because of their capacity to precipitate uterine contractions or labor. For those women who use antiepileptic drugs as a means of headache prevention, it is recommended that the drugs be stopped prior to pregnancy or as soon as it is known that pregnancy has begun.
In the special circumstance of true and debilitating status migrainosus during pregnancy, infusions of magnesium and metoclopramide (in doses previously mentioned in this chapter) are often used but repeated administration and monitoring of blood pressure and tendon reflexes may be needed. This should probably precede resorting to opioids, which may nevertheless become necessary in some cases. In all instances of headache in late pregnancy, the possibilities of toxemia and cerebral venous thrombosis should be considered.