SUNCT and SUNA syndrome
SUNCT is an acronym for short-lasting, unilateral, neuralgiform headache attacks with conjunctival injection and tearing. SUNA is an acronym for short-lasting unilateral neuralgiform headache attacks with autonomic symptoms. They are rare and often disabling primary headache disorders. They belong to the group of disorders known as the TACs. SUNCT and SUNA should be considered clinical phenotypes of the same syndrome. They are characterized by very frequent attacks of extremely short-lasting, unilateral headaches. The headaches of the SUNCT and SUNA syndromes recur from 3 to 200 times per day; each attack lasts 5 to 240 seconds each. As the name suggests, individual attacks are associated with ipsilateral conjunctival injection and lacrimation. Brain MRI should always be performed with a dedicated view to exclude neurovascular compression. The high percentage of remission after microvascular decompression (MVD) supports the pathogenetic role of neurovascular compression.
How are SUNCT and SUNA treated?
SUNCT and SUNA are very refractory to treatment. Treatment with medications used for cluster and the TACs are ineffective for SUNCT and SUNA. Lamotrigine, as an oral preventative treatment, and lidocaine, as an intravenous transitional treatment, seem to be the most effective therapies. For medically intractable chronic forms of SUNCT and SUNA, several surgical approaches have been tried. These include ablative procedures involving the trigeminal nerve or the Gasserian ganglion, MVD of the trigeminal nerve, and neurostimulation techniques.