Subsequently, Gardner (1968) reported 11 patients with the syndrome, all of whom had documented posterior fossa lesions (cirsoid aneurysms, arteriovenous malformations, and cholesteatomas). Maurice-Williams (1973) has re-emphasised that the coexistence of trigeminal neuralgia and hemifacial spasm signals the presence of a posterior fossa lesion.We recently examined a patient with painful tic convulsif and vertebrobasilar ectasia and, in consequence, undertook a systematic review of the literature. We discovered that less than half of the 41 reported cases provide sufficient clinical data for analysis and that only 10 patients with painful tic convulsif have been subjected to angiography, surgery, or postmortem examination. Moreover, although the signs and symptoms of patients suffering from it have been described, no attempt has yet been made to define the clinical syndrome or to discuss its diagnosis or the results of treatment. Accepted 19 October 1976 Case report A 67 year old woman was admitted to The New York Hospital with a five years' history of paroxysmal lancinating pain over the right jaw, radiating posteriorly to the ear. Paroxysms of pain were triggered by talking, chewing, or palpating the skin over the ramus of the right mandible; spontaneous paroxysms also occurred. Approximately two years after the onset of right-sided facial pain, she became aware of twitching in the right periorbital muscles, which spread during the ensuing months to involve the majority of the muscles innervated by the right facial nerve. These hemifacial spasms occurred without warning, could not be controlled by conscious effort, and were exacerbated by anxiety. There was no temporal relation between her rightsided facial pain and the attacks of facial hemispasm.The patient complained of mild bilateral hearing loss but denied tinnitus or vertigo. There was no history of headache, visual symptoms, facial paralysis, dysphagia, dysarthria, limb weakness, incoordination, sensory disturbance, or gait disorder.The general medical examination was unremarkable. Neurological examination revealed a right facial contracture (Fig. la) and spasmodic, irregular mass contractions of the right facial muscles, including the orbicularis oculi, levator anguli oris, and platysma. Both corneal reflexes were intact, and facial sensation was normal. Mild bilateral sensorineural deafness was confirmed by audiometry; Hallpike differential caloric tests were normal.