Abstract
The life-time prevalence of migraine was estimated to be about 8% in men and 25% in women (a male:female ratio of 1 : 3) in a population study conducted in Denmark by Rasmussen et al. (1). Migraine attacks tend to decrease in frequency with increasing age (2). Ischaemic stroke is a rare but serious complication of migraine. Numerous studies have been conducted in an attempt to determine an association between migraine and cerebral infarction. The association remains uncertain but most clinical studies agree that migrainous stroke is most common in women under the age of 45 suffering from migraine with aura, especially in the presence of recognized risk factors such as tobacco smoking and use of oral contraceptives (3, 4).
Case report
Our patient was a 93-year-old female, a widow who lived alone and was independent since, despite her advanced age, she was healthy both mentally and physically with the exception of migraine that she had had from an early age. She was not using any medications on a regular basis. She had never been a smoker and consumed normal amounts of alcohol. She had normal body weight and blood pressure.
The patient experienced migraine attacks at more or less regular intervals, once every 1–1.5 months. Her headache was preceded by a visual aura in the form of both positive (usually fortification spectrum) and negative features. The aura was followed by a strictly unilateral headache of pulsatile character affecting either the left or right hemicranium interchangeably. The headache lasted usually 24–48 h and was as a rule accompanied by photophobia, phonophobia, nausea, vomiting and generalized malaise. During an attack the patient preferred to remain in bed in a dim and quite environment and could not engage in any activities. The patient's migraine was diagnosed as type ‘1.2.1 typical aura with migraine headache’ according to the International Headache Society (IHS) criteria (5).
The patient was not treating her attacks with migraine-specific medication. She sometimes used over-the-counter analgesics, usually acetaminophen.
Presentation
The patient was admitted to our department in February 2005. She was experiencing a migrainous episode that had begun the day before admission. According to the patient's description, the attack had begun in the usual way with a visual aura in the form of her typical fortification spectrum in her left visual field. This was followed by a negative scotoma that covered most of her left visual field and, unlike her previous attacks, persisted in the headache phase. The visual manifestations were followed by a unilateral pulsatile right-sided headache, accompanied by nausea, vomiting and generalized weakness. The next day the patient was visited by family members who perceived her condition as unusually severe, being characterized by especially intense nausea and vomiting as well as somewhat unsteady gait. Another alarming feature was that her visual field defect had persisted. The family decided to seek medical attention and the patient was admitted to the hospital.
Clinical assessment
Upon clinical examination a left homonymous hemianopsia was discovered. The rest of the neurological and general clinical assessment was unremarkable.
Further diagnostic procedures
A computed tomographic (CT) examination of the patient's brain revealed a hypodense area in the right occipital lobe that was diagnosed as a fresh cerebral infarct. Diffusion magnetic resonance imaging (MRI) of the brain confirmed the presence of a fresh occipital infarct (see Fig. 1). MR angiography showed no abnormalities of the intracranial vascular network and classical anatomy with a symmetrical and complete Willis circuitry. Duplex ultrasound examination of the extracranial carotid and vertebral circulation was unremarkable, as was a Doppler examination of the intracranial vasculature. Unenhanced echocardiography was also essentially normal except from a grade I mitral insufficiency without any haemodynamic significance. The patient did not suffer from arrhythmias. Extensive blood tests revealed no abnormalities, including normal differential lipid and glucose values. Coagulation studies including thrombocytes, International Normalized Ratio, activated partial thromboplastin time, fibrinogen,
Diffusion weighted magnetic resonance image of the patient's brain depicting a right-sided fresh occipital infarct (arrow).
Follow-up
During her 2-week hospitalization period the patient showed significant improvement of her symptoms. She was hydrated with IV Ringer lactate and treated symptomatically with analgesics. The headache and gastrointestinal symptoms resolved about 48 h after admission. Her visual field defect also improved to a certain degree and by the end of the second week she was able to detect light flashes and hand movements in her left visual field. She was released from our department without further clinical or diagnostic follow-up.
Discussion
The criteria laid down by the IHS for diagnosing migrainous stroke are the following (5): (i) the present attack in a patient with 1.2 Migraine with aura is typical for previous attacks except that one or more aura symptoms persist for >60 min; (ii) neuroimaging demonstrates ischaemic infarction in a relevant area; (iii) the infarction cannot be attributed to another disorder.
Our patient had one of her typical attacks accompanied by persisting visual symptoms. A fresh infarct was demonstrated by CT and diffusion MRI imaging of the brain. Finally, no other cause for the infarct was demonstrated despite extensive examinations and no stroke risk factors where present. Therefore, we diagnosed the condition as 1.5.4 Migrainous infarction according to the IHS criteria.
Several studies have shown an increased risk for stroke in female migraineurs under the age of 45, but evidence for an association between migraine and ischaemic stroke in older women and men has until now been inconsistent. Migrainous infarction in a woman of such an advanced age is a rare clinical entity and, to the best of our knowledge, no similar reports are found in the medical literature. Our case shows that migraine might have a direct causal relationship to ischaemic cerebral infarct even in elderly individuals.