SUNCT and SUNA: an Update and Review

The purpose of this review is to provide an update on the clinical features, diagnosis, pathogenesis, epidemiology, and treatment of the rare primary headache disorders short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) and short-lasting unilateral neuralgiform headache attacks with autonomic symptoms (SUNA). Together these entities are known as short-lasting unilateral neuralgiform headache attacks (SUNHA).

Recent case reports of secondary SUNCT and SUNA due to medullary infarcts support the theory that the trigeminohypothalamic pathway is involved in the pathophysiology of SUNHA. While medical therapy for SUNHA has not significantly changed, surgical therapy for refractory SUNCT and SUNA has made advancements with a recent case series demonstrating the efficacy of deep brain stimulation. We will discuss the pathophysiology of both the pain and the autonomic symptoms experienced in SUNCT and SUNA attacks as well the medical, procedural, and surgical options for treatment with emphasis on recent advances. Specific secondary causes reported in the recent literature will be discussed in brief.