The prognostic value of facial nerve conduction velocity in patients with Bell's palsy

The facial nerve conduction velocity was measured in 30 healthy subjects (6 0 sides) and in 51 patients with a unilateral Bell's palsy. The normal valu e was 47.8 +/- 5.1 m/s. Incomplete recovery was common in Bell's palsy when the velocity was below 30 m/s. Mild synkinesis was observed in only one pa tient when the nerve conduction velocity was above 30 m/s. When the degree of degeneration revealed by electroneuroneography did not exceed 60%, the c onduction velocity was in the normal range. For degrees of degeneration in excess of this, the conduction velocity decreased in parallel with the incr ease in the degree of degeneration.