Although correlation does not imply causation, the temporal and lateral concordance of both cluster headache and moyamoya symptoms are consistent with such a relationship. Twice, cluster headache symptoms occurred contralateral to the moyamoya symptoms (in the ipsilateral hemisphere), and each time, cluster headache symptoms remitted with successful treatment of the moyamoya.
Secondary, or symptomatic cluster headache has been described from pituitary adenoma [
1,
2], meningiomas of the sphenoid wing [
3], upper cervical area [
4], and undersurface of the tentorium cerebelli [
5] (where inflammatory myofibroblastic tumor has also caused cluster headache) [
6], aneurysms of the anterior cerebral [
1], posterior cerebral [
7], vertebral [
8], and carotid arteries [
1], dissections of the vertebral [
9] and internal carotid arteries [
10,
11], arteriovenous malformations in the middle cerebral artery [
12] as well as occipital [
13], frontal, temporal, and parietotemporal lobes [
14‐
16], Wallenberg’s syndrome [
17], pituitary orbitosphenoidal aspergillosis [
18], head and neck injury [
19], ipsilateral enucleation [
20], calcified lesions close to the third ventricle [
21], cavernous sinus granulomatous tissue [
22], and post carotid endarterectomy [
23,
24].
Most symptomatic cases are from lesions located near the midline in the middle fossa of the skull base, although lesions involving structures that are innervated by branches of C2 can trigger cranial autonomic activation in humans [
25] and animals [
26], and C2 activation can sensitize trigeminal neurons that receive input from incracranial vessels [
27]. Disturbance of sympathetic nerve function, either in the plexus of parasympathetic, sympathetic, and sensory fibers in the connective tissue of the cavernous sinus/hypophyseal region or in the walls of the internal carotid artery is known to generate cluster headache, and it is possible that the progressive intimal thickening in the carotid walls of this patient and consequent sympathetic disruption exacerbated his attacks.