Positional headache induced by isolated middle cerebral artery dissection: Two case reports

Background Isolated middle cerebral artery dissection is uncommon and occurs in patients reporting headaches as the only symptom. This makes intracranial artery dissection challenging to diagnose and treat. Case description: We describe two cases of positional headache caused by isolated middle cerebral artery dissection, confirmed using high-resolution magnetic resonance imaging. The two patients presented with sudden-onset headache, occurring when lying in the lateral decubitus position. When lying down in the decubitus position ipsilateral to the intracranial artery dissection, the headache aggravated and middle cerebral artery flow velocity increased on transcranial Doppler ultrasonography compared to when in the supine position. Both patients were treated with antiplatelet agents, and the headache completely resolved within 1–2 weeks. Conclusion We recommend additional imaging studies evaluating intracranial artery dissection as a cause of positional headache.