Thunderclap headache as the primary clinical feature of a supratentorial embolic cerebral infarct

Abstract

A formula for the diagnostic assessment of thunderclap headache (TCH) should be established. The management of this type of headache is controversial. The established diagnostic assessment of TCH includes a computer tomography (CT) of the head and cerebrospinal fluid (CSF) examination to exclude a subarachnoid haemorrhage. In patients whose CT scans and CSF analyses are normal, further testing is rarely considered to be indicated by most clinicians [1]. However, others suggest that in circumstances where CT and CSF are normal, further diagnostic assessment with magnetic resonance imaging (MRI), magnetic resonance angiography (MRA) of the brain and neck, and magnetic resonance venography is necessary [2]. Articles differ in their conclusions and recommendations. A MRI-verified supratentorial embolic cerebral infarct with TCH as the primary clinical feature is to my knowledge not hitherto reported. Here is described a patient who experienced a TCH as the primary clinical feature of an embolic insula/temporal lobe infarct. A 41-year-old woman appeared in the emergency department following an acute and sudden onset of severe headache. The pain was located in the left temporal region, it reached its maximum intensity in \1 min and lasted for about 7 h. At the time of admission to hospital, the patient reported that the headache had waned. There was no previous history of headaches. Vital signs and physical examination were normal. Neurological examination was normal. Laboratory testing was within the normal range. Blood pressure monitoring was normal. An electrocardiogram (ECG) showed sinus rhythm. Cerebrospinal fluid (CSF) examination revealed a normal opening pressure (140 mmH2O), a normal closing pressure, a normal cell count, glucose and protein. Spectrophotometry disclosed no bilirubin. A CT scan of the head was normal. A magnetic resonance imaging (MRI) of the brain was carried out to exclude other causes of TCHs. It revealed an acute ischaemic lesion in the left insula/ temporal lobe (Fig. 1). A magnetic resonance angiography (MRA) was ordered to exclude intracranial aneurysms, cerebral venous thrombosis, dissection and reversible cerebral vasoconstriction syndrome. These investigations revealed an acute embolic occlusion of a main M2 segment branch of the left middle cerebral artery (Fig. 2). No dissection, reversible cerebral vasoconstriction syndrome or other abnormalities could be detected. Further investigations with ECG telemetry and echocardiography were normal. An additional MRI and MRA of the cervical arteries/intracerebral circulation 2 days later confirmed the cerebral infarct and the occlusion. An extensive laboratory testing revealed normal results. No source of the cerebral embolus could be found. The patient could be discharged and remains well. At follow-up after 6 months, she reported no headache. TCH is a very rare manifestation of a cerebral infarct. In 2006, a case report was published where a TCH was the presenting clinical feature of embolic cerebellar infarcts, in the absence of neurological findings [3]. Gossrau et al. [4] presented a similar case (cerebellar infarct) in 2008. Headache is not uncommon in ischaemic stroke, but is usually overshadowed by other manifestations such as aphasia and neglect [5]. It is usually focal and mild [5]. The character of the headache is throbbing [5]. The severity of the headache is not related to the size of the infarct or the location of the lesion [5]. B. Edvardsson (&) Department of Neurology, Faculty of Medicine, Lund University Hospital, 221 85 Lund, Sweden e-mail: Bengt.Edvardsson@med.lu.se