Short-Lasting Unilateral Neuralgiform Headache Attacks

Short-lasting unilateral neuralgiform headache attacks (SUNHA) is characterized by strictly unilateral trigeminal distribution pain that occurs in association with ipsilateral cranial autonomic features. There are two subtypes: short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) and short-lasting unilateral neuralgiform headache attacks with cranial autonomic symptoms (SUNA). These disorders are rare but highly disabling. The management of SUNHA can be challenging. The abortive therapies are not generally useful as the attacks are relatively short-lasting. A myriad of pharmacological preventive treatments has been tried in single case reports or small series in an open-label fashion. Lamotrigine, as an oral preventive treatment, and lidocaine, as an intravenous transitional treatment, seems to be the most effective therapies. For medically intractable SUNHA, several surgical approaches have been tried. These include ablative procedures involving the trigeminal nerve or the Gasserian ganglion, microvascular decompression (MVD) of the trigeminal nerve, and neurostimulation techniques. MVD, occipital nerve stimulation, and ventral tegmental area deep brain stimulation have all been found to be effective in open-label series with relatively high-response rates. There is a considerable clinical, therapeutic, and radiological overlap between SUNCT, SUNA, and trigeminal neuralgia (TN). Despite being considered distinct conditions, the emerging evidence suggests a broader nosological concept of SUNCT, SUNA, and TN; these conditions may constitute a continuum of the same disorder, rather than separate clinical entities. Consideration needs to be given to classifying SUNHA with TN as a cranial neuralgia rather than as a trigeminal autonomic cephalalgia.