Hemifacial spasm is a distressing, common, and well defined condition, which is difficult to treat. It is characterised by clonic and tonic contractions of the muscles supplied by the facial nerve, is intermittent, and is usually worsened by fatigue or emotional upsets.

A clinical picture similar to that of hemifacial spasm is also seen in trigeminal neuralgia, another condition for which widely varying pathophysiological bases, including vascular compression, have been proposed.1

In our case postmortem exploration of the posterior cranial fossa disclosed a strikingly abnormal relation between the anterior inferior cerebellar artery and VIIth cranial nerve. Such abnormal vascular anomalies around the facial nerve are repeatedly reported in the literature, and they seem to be closely correlated with hemifacial spasm.2

We took the cadaver of a man who had died aged 51, from the dissection material held by the First Department of Anatomy at the University of Vienna.

A square 2 cm×2 cm was drilled in the centre of the skull cap. formalin:water (1:5; 30 ml) was injected subdurally. The cadaver was left in the cold room …