Long-term effect of prednisolone on functional blink recovery after transient peripheral facial motor paralysis.

Abstract

To determine the functional recovery in patients with severe transient peripheral facial motor paralysis (Bell palsy). Prospective controlled trial. Academic medical center. Blink recovery was studied in 2 groups of severely affected Bell palsy patients during a follow-up period of 84 weeks. The patients in one group received prednisolone within the first week after the onset of symptoms. No medication was given to the other group. A control group of healthy subjects was also included. Simultaneous orbicularis oculi muscle activity and eyelid kinematics were recorded by surface electromyographic (EMG) recording and eyelid search coils, respectively. At the beginning of the paralysis, very little integrated orbicularis oculi muscle activity and eyelid movement was measured at the palsied side of the face. Thirteen weeks later, the integrated orbicularis oculi EMG and functional blink recovery gradually improved until 39 weeks. Beyond, only the integrated orbicularis oculi EMG slightly increased. At 84 weeks, the integrated orbicularis oculi EMG was significantly larger in the prednisolone group compared with the control group. The integrated EMG of the nonmedicated group recovered to normal values. Curiously enough, the functional blink recovery at the palsied side remained reduced to 64% compared with the healthy controls in the prednisolone-treated group and to 36% in the nonmedicated group. The authors demonstrate that prednisolone significantly increased the orbicularis oculi muscle activity and significantly improved functional blink recovery in severely affected Bell palsy patients. However, the increase of muscle activity was insufficient to restore functional blinking to normal values.