Trigeminal neuralgia with lacrimation or SUNCT syndrome?

An intimate relationship between trigeminal neuralgia (TN) and short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) syndrome, based on similar clinical signs and symptoms and on cases demonstrating possible "transformation" from one entity to the other, has been widely accepted. We evaluated the presence of lacrimation in 22 consecutive cases that had been diagnosed as TN. Ipsilateral lacrimation was reported by 6 such cases (5M, 1F). These cases responded to antineuralgic therapy with concomitant resolution of lacrimation and were clinically very similar to TN. The differential diagnosis and the possibility of lacrimation in TN are discussed.