A. Attacks fulfilling criteria for 3.3 Short-lasting unilateral neuralgiform headache attacks
B. Both of conjunctival injection and lacrimation (tearing).
The literature suggests that the most common mimic of 3.3.1 SUNCT is a lesion in the posterior fossa.
Patients have been described in whom there is overlap between 3.3.1 SUNCT and 13.1 Trigeminal neuralgia. Differentiation is clinically complex. Such patients should receive both diagnoses.
Patients with both 3.3.1 SUNCT and 3.1 Cluster headache have been reported; the pathophysiological significance of this overlap is yet to be determined.