Surgical interventions for the early management of Bell's palsy
Abstract
Background
Bell's palsy is an acute paralysis of one side of the face of unknown aetiology. Bell's palsy should only be used as a diagnosis in the absence of all other pathology. As the proposed pathophysiology is swelling and entrapment of the nerve, some surgeons suggest surgical decompression of the nerve as a possible management option.
Objectives
The objective of this review was to assess the effectiveness of surgery in the management of Bell's palsy and to compare this to outcomes of medical management.
Search methods
We searched the Cochrane Neuromuscular Disease Group Specialized Register (23 November 2010). We also searched the Cochrane Central Register of Controlled Trials (CENTRAL) (23 November in The Cochrane Library, Issue 4 2010). We adapted this strategy to search MEDLINE (January 1966 to November 2010) and EMBASE (January 1980 to November 2010).
Selection criteria
We included all randomised or quasi‐randomised controlled trials involving any surgical intervention for Bell's palsy.
Data collection and analysis
Two review authors independently assessed whether trials identified from the search strategy were eligible for inclusion. Two review authors assessed trial quality and extracted data independently.
Main results
Two trials with a total of 69 participants met the inclusion criteria. The first study considered the treatment of 403 patients but only included 44 in their surgical study. These were randomised into a surgical and non surgical group. The second study had 25 participants which they randomly allocated into surgical or control groups.
The nerves of all the surgical group participants in both studies were decompressed using a retroauricular approach. The primary outcome was recovery of facial palsy at 12 months. The first study showed that both the operated and non operated groups had comparable facial nerve recovery at nine months. This study did not statistically compare the groups but the scores and size of the groups suggested that statistically significant differences are unlikely. The second study reported no statistically significant differences between their operated and control groups. One operated patient in the first study had 20 dB sensorineural hearing loss and persistent vertigo.
Authors' conclusions
There is only very low quality evidence from randomised controlled trials and this is insufficient to decide whether surgical intervention is beneficial or harmful in the management of Bell's palsy.
Further research into the role of surgical intervention is unlikely to be performed because spontaneous recovery occurs in most cases.
PICOs
Plain language summary
Surgical operation for idiopathic facial paralysis
There is insufficient evidence to support surgical operation for the management of Bell’s palsy.
Bell’s palsy is a paralysis of the muscles of the face, usually on one side, that has no known cause. People generally recover but there is a small group who do not recover. It is thought to be caused by swelling and entrapment of the nerve. Some surgeons thought that an operation to release the nerve may improve recovery.
Two studies were included in our review. They compared surgery with non‐surgical management of 69 participants with Bell's palsy in total. The first study did not state how the participants were randomly allocated into surgical and non‐surgical groups. The second study allocated their participants randomly using statistical charts into surgical and control groups (no treatment). There was no attempt in either study to hide which groups patients were being allocated into and both patients and assessors were aware of the management plan proposed. The first study lost seven participants to follow‐up and there were no losses to follow‐up in the second study.
The most important outcome was recovery of facial palsy at 12 months. The first study showed that the operated and non operated groups both had comparable facial nerve recovery at nine months. The second study reported no differences in recovery of the facial palsy between their operated and control groups at one year. One patient operated on in the first study had mild hearing loss and vertigo after the surgery.
The review found that there was only very low quality evidence and that this was insufficient to decide whether an operation would be beneficial or harmful in the management of Bell's palsy.
Further research into the role of an operation is unlikely to be performed because spontaneous recovery occurs in most cases.
