Trigeminal autonomic cephalalgia sine headache

Area of Science:

• Neurology
• Headache Medicine

Background:

• Cluster headache without headache (CH-H) and paroxysmal hemicrania without headache (PH-H) are rare but described headache disorders.
• These conditions present with autonomic and/or extracephalic symptoms without the typical headache pain.

Purpose of the Study:

• To describe new cases of CH-H and PH-H.
• To propose a unifying term, trigeminal autonomic cephalalgia without headache (TAC-H), for these and similar presentations.
• To explore the pathophysiological underpinnings of TAC-H.

Main Methods:

• Case series of three CH-H patients and one probable PH-H patient.
• Literature review for additional cases of CH-H and PH-H.
• Discussion of pathophysiological mechanisms, including hypothalamic and superior salivatory nucleus involvement.

Main Results:

• New cases of CH-H and PH-H were identified.
• Literature search revealed additional cases supporting the existence of CH-H and PH-H.
• CH-H attacks may exhibit shorter minimal duration compared to typical CH attacks.

Conclusions:

• The term trigeminal autonomic cephalalgia without headache (TAC-H) is proposed for autonomic attacks lacking headache.
• TAC-H may include secondary forms developing after treatment for painful TACs.
• Pathophysiology may involve diencephalic-hypothalamic activation of the superior salivatory nucleus without nociceptive input.