Introduction
Disfiguring facial weakness, synkinesis, higher depression rates and lower self-esteem are some of the dramatic consequences of a non-completely recovered facial palsy.Reference Walker, Hallam, Ni Mhurchadha, McCabe and Nduka1, Reference Gilden2 There is probably no benign ailment that causes more physical and emotional suffering.Reference Pulec and Pensak3, Reference Pulec4 Therefore, everything should be done to promote recovery. Patients should be counselled and not forced into either therapy or ‘watchful waiting’.Reference Mulley, Trimble and Elwyn5 Contraindications to treatment may in individual cases outweigh the potential benefits.
Decision makers need to assess and appraise all levels of evidence; the strengths and weaknesses of each need to be understood if reasonable and reliable conclusions are to be drawn.Reference Rawlins6 Much has been written about Bell's palsy in cohort and case studies. Every aspect of Bell's palsy has been the subject of a continuing dispute in the literature.Reference McNeill7, Reference Gantz, Rubinstein, Gidley and Woodworth8 Therefore, anatomy, relevant pathophysiology, natural course of the disease, relevant pharmacotherapy or surgical procedures, success and failure rates, and possible side effects of therapy, need to be reconsidered.
Pathophysiology
The term Bell's palsy is reserved for those cases in which there is no obvious cause (such as injury, infection or tumour), or in which there is nothing to suggest a more centrally placed lesion.Reference Cawthorne9
Although it refers to a supposedly ‘idiopathic’ lesion, many theories have been developed. Bell's palsy has been attributed to cold exposure, chill or rheumatism.Reference Aminoff10–Reference Van der Graaf, Ijpma, Nicolai and Werker12 Nowadays, most literature suggests that Bell's palsy is caused by infection with the herpes simplex virusReference Sade13–Reference Kennedy20 or varicella zoster virus.Reference Morris21–Reference Hato, Matsumoto, Kisaki, Takahashi, Wakisaka and Honda25 If this is true, the typical vesicles of the zoster are not present.
The inflammatory reaction against these viruses causes swelling of the facial nerve, which consequently becomes entrapped within its narrow bony canal.Reference McNeill7, Reference Duel26 Many authors have described the swollen nerve.Reference Morris21, Reference Giancarlo and Mattucci27–Reference Hagino, Tsunoda, Tsunoda and Kishimoto30 In the end, this theory might concur with a theory of ischaemic aetiology.Reference Yanagihara, Honda, Hato and Murakami31, Reference Taverner32 In cases of longstanding paralysis, the facial nerve was reduced to a shrunken strand.Reference McGovern and Hansel33, Reference McGovern34 Contrast enhancement of the facial nerve seen on magnetic resonance imaging, and the possible narrower canal on computed tomography scanning that patients with repeated palsies may have, provides circumstantial evidence that might support the theory.Reference Millen, Daniels and Meyer35, Reference Murai, Kariya, Tamura, Doi, Kozakura and Okano36
Anatomy
The facial nerve runs through the temporal bone. The narrowest portion is found at the entrance. A tight arachnoid band is found adherent to the nerve in this region, which contributes to the constriction.Reference Gantz, Rubinstein, Gidley and Woodworth8, Reference Ge and Spector37
Natural course
About 70 per cent of patients recover completely without any therapy,Reference Peitersen38, Reference Mathews39 and 15 per cent more might still have a ‘good’ recovery.Reference Pickerill and Pickerill40, Reference Tumarkin41
Patients with an initial severe palsy, the elderly and patients with diabetes have a higher chance of non-recovery or complications.Reference Aminoff10, Reference Ge and Spector37, Reference Peitersen38, Reference Lejeune, Bernat, Vitte, Lamas, Willer and Soudant42–Reference Kanazawa, Haginomori, Takamaki, Nonaka, Araki and Takenaka46 There is a less than 50 per cent chance of a spontaneous, complete recovery in those aged over 60 years.
Herpes zoster oticus is associated with a worse outcome than Bell's palsy; pain might be suggestive of a zoster sine herpete.Reference Gilden2, Reference Ge and Spector37, Reference Pulec47 The prognosis has been found to be worse when the onset of the palsy was accompanied by marked pain and loss of taste than when the onset was symptomless.Reference Cawthorne9, Reference Giancarlo and Mattucci27, Reference Tumarkin41, Reference Pulec47–Reference Peiris and Miles49
Because of the high spontaneous recovery rate, it is interesting to examine cases of non-recovery and failure rates. How well does a specific treatment prevent a disfiguring result?
Treatment
The main priority is to reduce nerve swelling. Corticosteroids are the first choice of treatment. Decompression gives more space to the swollen nerve. Given the probable viral pathogenesis, antiviral drugs could be useful.
Function assessment, grading and success rates
The use of different grading scales for the assessment of dynamic facial nerve function makes comparison regarding Bell's palsy therapy difficult.Reference De Ru, Van Benthem and Janssen50 Of note, the commonly used House–Brackmann grading scale was mainly based on patients diagnosed with cerebellopontine angle pathology. Is facial nerve function following such pathology comparable to Bell's palsy in terms of assessment?Reference House and Brackmann51–Reference Wormald, Ahmed and Fenton53 A scale with more possibilities for differentiation and one that integrates subjective scoring by the patient – the movement, rest, secondary defects, and subjective scoring grading scale (‘MoReSS’),Reference De Ru, Braunius, Van Benthem, Busschers and Hordijk54 for example – might be advisable for future studies.
Current treatment
Based on the ‘probable pathophysiology’, on the best available research and on our clinical expertise, the main points in Bell's palsy treatment are as follows. Firstly, treatment should start as early as possible. Secondly, treatment with steroids is indicated in most patients; the cost is low and the side effects are minor. Thirdly, one should identify the patients with a likelihood of non-recovery (House–Brackmann grades IV, V and VI), and treat them with a combination of steroids and antivirals. Fourthly, if complete recovery is not likely to be achieved, as can be assessed with electrophysiological tests (e.g. electroneurography (ENoG) and electromyography (EMG)), the patients should be referred (if that is their wish) to the ‘best’ surgeons for decompression surgery as soon as possible.Reference Gantz, Rubinstein, Gidley and Woodworth8, Reference Aminoff10, Reference Hato, Matsumoto, Kisaki, Takahashi, Wakisaka and Honda25, Reference Williamson and Whelan45, Reference De Ru, Van Benthem and Janssen50, Reference Brown55–Reference Adour, Ruboyianes, Von Doersten, Byl, Trent and Quesenberry63
Over the last 15 years, patients in our clinics with moderate and severe palsy (House–Brackmann grades IV, V and VI ) have been treated with corticosteroids and antivirals. Prednisone 1 mg/kg or 80 mg for one week is prescribed; we want a high dose for prompt relief of the nerve. In severe cases, valaciclovir 1000 mg three times a day for one week is prescribed.
This regime has been maintained because of the good results. With this medication scheme, indications for decompression surgery to treat Bell's palsy were rare. Surgical intervention can be helpful in those cases that do not respond to medical measures. The results of our clinical practice are in line with those of Yanagihara et al.,Reference Yanagihara, Honda, Hato and Murakami31 which showed that the number of patients undergoing a decompression operation was in decline.
Treatment revisited
What is the evidence for our protocol? This issue is important because on average 85 per cent of patients have a ‘rather good’ recovery without therapy. Furthermore, this percentage might be higher when corticosteroids are prescribed, and it will be difficult to prove any added value of antivirals or decompression surgery as there will be a ceiling effect.Reference Aminoff10, Reference De Ru, Martens and Van der Veen64, Reference Burgess, Yim and Lepore65
Our questions are as follows. Firstly, does antiviral medication, combined with steroids, improve the recovery of patients with severe palsy? Secondly, does decompression surgery ameliorate the outcome in severe cases that do not show improvement with medical therapy?
This paper is not just another new systematic review. Reviews on Bell's palsy have been published on many occasions. In those, the same articles seem to be reviewed over and over again. In our opinion, another meta-analysis with no new results would not be useful if any outcome was measured in the traditional way.Reference Moher66 Therefore, we have used the data and reference lists of previous systematic reviews, but we focus on a different interpretation of the current literature.
Antiviral medication
Over the last 75 years, a viral cause for Bell's palsy has been suggested. Therefore, antiviral treatment is likely to benefit patients, providing that treatment is started early and that the severe cases are given a high enough dose to cover an infection with varicella as well.Reference Murakami, Mizobuchi, Nakashiro, Doi, Hato and Yanagihara15, Reference Morgan, Moffat, Ritchie, Collacott and Brown22–Reference Hato, Yamada, Kohno, Matsumoto, Honda and Gyo24, Reference Moher66
Hato et al.Reference Hato, Matsumoto, Kisaki, Takahashi, Wakisaka and Honda25 has previously described the difference in recovery in severely affected patients treated with combination therapy versus monotherapy steroid treatment in a retrospective study conducted in 2003. If the data from the paper by Quant et al.Reference Quant, Jeste, Muni, Cape, Bhussar and Peleg67 are updated, the results of combination therapy in prospective trials are likely to be significantly better than those for monotherapy, with an odds ratio of 1.712 (95 per cent confidence interval (CI) = 1.172–2.501) (Table I).Reference Yeo, Lee, Park and Cha19, Reference Hato, Yamada, Kohno, Matsumoto, Honda and Gyo24, Reference Ryu, Lee, Lee, Park and Yeo43, Reference Adour, Ruboyianes, Von Doersten, Byl, Trent and Quesenberry63, Reference Sullivan, Swan, Donnan, Morrison, Smith and McKinstry68–Reference Lee, Byun, Park and Yeo71
Table I Prospective trials comparing combination therapy with steroids only*
Pooled values: I2 index = 27.4 per cent; p-value Q = 0.210; meta-analysis random-effects model odds ratio = 1.712 (95 per cent confidence interval (CI) = 1.172–2.501). ‘Odd ones out’ principle values (deleting the studies with the most negative and most positive results, i.e. deleting Sullivan et al.Reference Sullivan, Swan, Donnan, Morrison, Smith and McKinstry68 and Adour et al.Reference Adour, Ruboyianes, Von Doersten, Byl, Trent and Quesenberry63): I2 index = 0.0 per cent; p-value Q = 0.606; meta-analysis random-effects model odds ratio = 1.787 (95 per cent CI = 1.277–2.500).
* Based on the meta-analysis by Quant et al.Reference Quant, Jeste, Muni, Cape, Bhussar and Peleg67 (and their correction); the data of Ryu et al.Reference Ryu, Lee, Lee, Park and Yeo43 and Lee et al.Reference Lee, Byun, Park and Yeo71 have been added.
Table II shows that the pooled odds ratio for patients with initial severe palsy recovering to at least House–Brackmann grade II is 1.985 (95 per cent CI = 1.334–2.952).Reference Cawthorne9, Reference Hato, Yamada, Kohno, Matsumoto, Honda and Gyo24, Reference Ryu, Lee, Lee, Park and Yeo43, Reference Adour, Ruboyianes, Von Doersten, Byl, Trent and Quesenberry63, Reference Sullivan, Swan, Donnan, Morrison, Smith and McKinstry68–Reference Axelsson, Berg, Jonsson, Engström, Kanerva and Stjernquist-Desatnik73
Table II Prospective trials comparing combination therapy with steroids only in patients with severe palsy*
Pooled values related to the likelihood of ‘good’ recovery: I2 = 0.0 per cent; p-value Q = 0.493; meta-analysis random-effects model odds ratio = 1.985 (95 per cent confidence interval (CI) = 1.334–2.952). ‘Odd ones out’ principle values (deleting the studies with the most negative and most positive results, i.e. deleting Sullivan et al.Reference Sullivan, Swan, Donnan, Morrison, Smith and McKinstry68 and Yeo et al.Reference Yeo, Lee, Park and Cha19): I2 = 0.0 per cent; p-value Q = 0.636; meta-analysis random-effects model odds ratio = 2.078 (95 per cent CI = 1.365–3.164). Based on a previous article;Reference Van der Veen, Rovers, De Ru and Van der Heijden72 the data of Ryu et al.Reference Ryu, Lee, Lee, Park and Yeo43 and Lee et al.Reference Lee, Byun, Park and Yeo71 have been added. The Engström et al.Reference Engström, Berg, Stjernquist-Desatnik, Axelsson, Pitkaranta and Hultcrantz69 findings have been updated with data from Axelsson et al.Reference Axelsson, Berg, Jonsson, Engström, Kanerva and Stjernquist-Desatnik73
Only one outlier exists, namely the study by Sullivan et al.Reference Sullivan, Swan, Donnan, Morrison, Smith and McKinstry68 Criticism of that particular study has already been described extensively.Reference De Ru74
In cases where the ENoG responsive level was less than 10 per cent compared to the contralateral side, indicating that patients had severe palsy, the recovery rate for combination therapy was 63.6 per cent (7 out of 11 patients recovered), and for steroids only it was 36.4 per cent (4 out of 11 patients recovered).Reference Lee, Byun, Park and Yeo71 Twenty-eight per cent of patients on combination therapy showed recovery of four House–Brackmann points or more, versus only 11.9 per cent of patients on corticosteroids.Reference Minnerop, Herbst, Fimmers, Kaabar, Matz and Klockgelter70
As well as having a higher percentage of full recovery, combination therapy results in significantly fewer sequelae and fewer patients with an unsatisfactory recovery (worse than House–Brackmann grade III) compared with those treated with steroids only (Table III).Reference Hato, Matsumoto, Kisaki, Takahashi, Wakisaka and Honda25, Reference Adour, Ruboyianes, Von Doersten, Byl, Trent and Quesenberry63, Reference Minnerop, Herbst, Fimmers, Kaabar, Matz and Klockgelter70, Reference Lee, Byun, Park and Yeo71, Reference Ahangar, Hosseini and Saghebi75 In the studies by Minnerop et al.Reference Minnerop, Herbst, Fimmers, Kaabar, Matz and Klockgelter70 and Lee et al.,Reference Lee, Byun, Park and Yeo71 the patients who did not recover to House–Brackmann grade IV were all in the monotherapy group. Synkinesis more frequently occurs following therapy with steroids only than following combination therapy.Reference Axelsson, Berg, Jonsson, Engström, Kanerva and Stjernquist-Desatnik73, Reference De Ru, Blackburn, McAlister, Brennan, Featherstone and Van der Veen76
Table III Numbers of patients with poor recovery, in prospective and retrospective studies
In line with the consistency criterion for causation, we could ask ‘has the outcome been repeatedly observed by different persons, in different places, circumstances and times?’Reference Hill77 With combination therapy, broadly the same answer has been reached in quite a variety of situations. Hence, we can justifiably infer that the effect is not due to some constant error.
Considering the above, we think that antiviral medication can improve recovery in patients with severe Bell's palsy.
Davenport et al.Reference Davenport, Sullivan, Smith, Morrison and McKinstry78 stated that the Scottish Bell's palsy study was performed because of a concern regarding the longstanding acceptance of steroid use, and the increasing acceptance of acyclovir use, despite insufficient evidence. The authors concluded that ‘steroids are now evidence based, but we have shown acyclovir to be ineffective’. They urged colleagues to consider further trials rather than propagate the use of an unproven treatment.Reference Davenport, Sullivan, Smith, Morrison and McKinstry78
In our opinion, it should have been clear in 2000 that corticosteroids ameliorate the outcome. However, because of doubts regarding the longstanding acceptance of steroid use, two double-blind, randomised trials were performed at this point.Reference Sullivan, Swan, Donnan, Morrison, Smith and McKinstry68, Reference Engström, Berg, Stjernquist-Desatnik, Axelsson, Pitkaranta and Hultcrantz69 In these trials (n = 416 and n = 245), patients were randomised to receive no steroids. Of these, about 66 more (10 per cent – a conservative low estimate) would have recovered with steroids. In our opinion, this indicates a lot of missed chances for recovery. We urge colleagues not to ignore history once again when it comes to the use of antivirals.
Combination therapy meta-analyses
Meta-analyses have generally concluded that antiviral therapy has no significant effect. However, if antiviral drugs have little added value when all patients are considered without differentiation, this does not necessarily mean that specific groups might not benefit from their prescription.
There were a number of points raised in the recent meta-analyses (Table IV); these are described briefly below.Reference Thaera, Wellik, Barrs, Dunckley, Wingerchuk and Demaerschalk62, Reference Quant, Jeste, Muni, Cape, Bhussar and Peleg67, Reference Lockhart, Daly, Pitkethly, Comerford and Sullivan79–Reference Numthavaj, Thakkinstian, Dejthevaporn and Attia82
Table IV Overview of conclusions made in meta-analysis studies
Firstly, in the conclusion of the abstract, the Cochrane review does not refer to combination therapy, but only to antivirals versus placebo or corticosteroids.Reference Lockhart, Daly, Pitkethly, Comerford and Sullivan79 This really is not the issue anymore.
Secondly, the Cochrane review ignores the fact that its own results indicate there was ‘a significant but slight reduction in the rate of incomplete recovery, favouring the combination of antivirals and corticosteroids over corticosteroids alone; RR [relative risk] 0.64 (0.50 to 0.82)’.Reference Lockhart, Daly, Pitkethly, Comerford and Sullivan79 Thus, only one study reports negative findings; yet still the Cochrane review concludes that antivirals, though in contradiction with their own calculations, are not effective. Does this reflect a bias given the overlap between the authors of the only study with negative findings and the Cochrane review authors?
Thirdly, the Cochrane review concludes that ‘there was no significant difference in long-term sequelae comparing antivirals + corticosteroids with corticosteroids alone, RR [relative risk] = 0.39, (CI 95% = 0.14, 1.07)’.Reference Lockhart, Daly, Pitkethly, Comerford and Sullivan79 This result might be clinically very relevant.
Fourthly, the study by Goudakos and Markou includes two trials that are not accessible to us, one of which, according to the title, appears not to concern Bell's palsy.Reference Goudakos and Markou81
Fifthly, an important fact in the meta-analysis by Quant et al.Reference Quant, Jeste, Muni, Cape, Bhussar and Peleg67 is that the figures from Engström's trial have been reversed. If the analysis was performed with the correct figures, the odds ratio becomes 1.72 (95 per cent CI = 1.02–2.88).Reference De Ru, Martens and Van der Veen64 The correct difference in the proportion of recovered patients amongst those who received steroids alone and those who received combination therapy now becomes 92.2 per cent minus 87.2 per cent. This 5 per cent is a clinically very relevant effect. Another effect of using the correct figures is that the heterogeneity index drops from 47.1 to 32.4 per cent, making a fixed-effects model instead of a random-effects model a serious option, resulting in a smaller confidence interval odds ratio of 1.69 (95 per cent CI = 1.12–2.53).
Sixthly, there are two meta-analyses that include trials in their funnel plot by means of a ‘trim and fill’ algorithm employed to correct for possible publication bias. Although this method can be valuable, it relies heavily on the assumption that unpublished, extremely negative studies exist. In fact, this is a very unlikely assumption when it concerns studies in which antivirals are used to treat a viral cause.Reference Quant, Jeste, Muni, Cape, Bhussar and Peleg67, Reference Numthavaj, Thakkinstian, Dejthevaporn and Attia82
Nevertheless, ‘extreme’ effects might be influencing outcomes. Therefore, we suggest using the ‘odd ones out’ principle as a sensitivity analysis, leaving out the studies with the most negative result (Sullivan et al.Reference Sullivan, Swan, Donnan, Morrison, Smith and McKinstry68) and the most positive result (Adour et al.Reference Adour, Ruboyianes, Von Doersten, Byl, Trent and Quesenberry63 in Table I and Yeo et al.Reference Yeo, Lee, Park and Cha19 in Table II). This method leads to a dramatic drop of the heterogeneity index in both tables (IReference Gilden2 = 0.0 per cent). This is mainly because of the removal of the Sullivan et al.Reference Sullivan, Swan, Donnan, Morrison, Smith and McKinstry68 trial, which reported results that do not concur at all with our clinical expectations (i.e. that patients with severe palsy using a combination of antivirals and corticosteroids recover worse than those using corticosteroids only). In Table I, the odds ratio becomes 1.787 (95 per cent CI = 1.277–2.500) and in Table II it becomes 2.078 (95 per cent CI = 1.365–3.164). Both results indicate a larger effect of using combination therapy.
The real outlier would seem to be the Sullivan et al.Reference Sullivan, Swan, Donnan, Morrison, Smith and McKinstry68 study. The authors suggested that the detrimental effect on recovery of antiviral medication could be due to a Jarisch–Herxheimer reaction.Reference Lockhart, Daly, Pitkethly, Comerford and Sullivan79 In our clinical experience, we have never seen this reaction. Moreover, no other study has reported such an adverse effect.
What is the harm of adding antiviral therapy? Theoretically, antivirals can cause gastroesophageal complaints, renal failure and headache; however, in the studies analysed, the side effects did not differ significantly amongst study groups. Famciclovir is sometimes recommended over acyclovir because of an easier dosage schedule and fewer gastrointestinal side effects.Reference Ramsey, DerSimonian, Holtel and Burgess83
The effect of non-complete recovery is lifelong morbidity. The price of valaciclovir or Famvir™ to prevent sequelae is about €150.
Thus, the answer to the first question, does antiviral medication combined with steroids improve the recovery of patients with severe palsy, is affirmative. Antivirals should be given to patients with (moderate) severe palsy.
Decompression surgery
Does decompression surgery ameliorate the outcome in severe cases of Bell's palsy that do not show improvement with medical therapy? The swollen nerve can be given more space with decompression and therefore this treatment fits well with the pathophysiology.Reference Gantz, Rubinstein, Gidley and Woodworth8 The earlier it is done, the less danger there will be of permanent impairment.Reference Morris21, Reference Jongkees29, Reference Kanazawa, Haginomori, Takamaki, Nonaka, Araki and Takenaka46, Reference Jongkees84 Theoretically, the only hope of restoring bilaterally co-ordinated emotional expression after paralysis of the facial nerve lies in restoration of the functional integrity of that nerve.Reference Ney11
All agree that decompression is not the mainstay of treatment for Bell's palsy. It should be preserved for special cases; it is more relevant in patients who are less likely to recover spontaneously.Reference Gantz, Rubinstein, Gidley and Woodworth8, Reference Cawthorne9, Reference Huizing, Mechelse and Staal85 Decompression is indicated for a medically treated patient with no signs of recovery of a total paralysis, and ENoG findings showing more than 95 per cent loss of activity, and without voluntary movement potentials on EMG.Reference Gantz, Rubinstein, Gidley and Woodworth8, Reference Giancarlo and Mattucci27, Reference Yanagihara, Hato, Murakami and Honda86–Reference Hopp and Hambley88 From reports by McNeill,Reference McNeill7 Gantz et al.,Reference Gantz, Rubinstein, Gidley and Woodworth8 Yanagihara et al.Reference Yanagihara, Gyo, Yumoto and Tamaki89 and Alford et al.,Reference Alford, Sessions and Weber90 it is clear that the timing and extent of decompression are of utmost importance for the recovery and development of sequelae.
Thus, the very nature and duration of the lesion for which decompression is justified make complete recovery unlikely. Yanagihara et al.Reference Yanagihara, Gyo, Yumoto and Tamaki89 and others have reported an interesting and significant feature: in some patients who have undergone decompression, there is some return of movement within a week of the operation.Reference Cawthorne9 This is a striking effect, and, as described by Glaziou et al.,Reference Glaziou, Chalmers, Rawlins and McCulloch91 is strongly suggestive of a genuine treatment consequence.
TumarkinReference Tumarkin41 reported that in the 20 per cent of patients who are not likely to recover spontaneously, the evidence indicates a more central involvement (herpes oticus) extending to the genu. Gantz et al.Reference Gantz, Rubinstein, Gidley and Woodworth8 stated correctly that the findings of previous studies evaluating the efficacy of surgical decompression in Bell's palsy that did not include decompression of the nerve medial to the geniculate ganglion (at the narrowest site) should not be generalised to support the notion that surgical decompression is not effective.Reference De Ru, Van Benthem and Janssen50
If a surgical intervention is established as a useful treatment option based on the good results shown by some surgeons, it does not necessarily mean that any surgeon should perform this treatment. Rather, it means that special cases are better off in special hands.Reference De Ru, Van Benthem and Janssen50 Whereas the effects of treatment with medication are probably generalisable to a certain extent, surgical results are – because of individual skills and the rarity of cases needing surgery – definitely not. Hence, to quote Sir Terence Cawthorne, who, when asked – discussing the vestibulocochlear nerve – to state which datum would most strongly influence his decision whether to proceed to an operation or not, answered: ‘the name of the surgeon’.Reference Jongkees84
Decompression surgery is associated with a broad range of possible collateral damage, varying from hearing loss to intracranial complications. Nevertheless, as concluded by MorrisReference Morris21 (who admittedly performed only transmastoid surgery), ‘there is no reason why, if decompression is carried out carefully, there should be any injury to the nerve at all, and the hearing will not be interfered with’. Gantz et al.Reference Gantz, Rubinstein, Gidley and Woodworth8 and Yanagihara et al.Reference Yanagihara, Hato, Murakami and Honda86 have reported a low incidence of collateral damage, even when more extensive types of surgery were undertaken.
Sinha et al.Reference Sinha, Keith and Pensak92 concluded that, of the patients who showed greater than 90 per cent of compound action potential reduction in the affected side, almost half (47 per cent) had normal to near normal recovery, indicating no need for therapy. However, if we reverse our thinking, more than half will end up with sequelae. In addition, other studies have shown no benefit and other authors were sceptical.Reference Mechelse, Goor, Huizing, Hammelburg, van Bolhuis and Staal93, Reference Adour94
Reports published in the last five years show good outcomes after decompression surgery in the patient group with a poor prognosis.Reference Hato, Nota, Komobuchi, Teraoka, Yamada and Gyo95, Reference Cannon, Gurgel, Warren and Shelton96
With regard to question two, does decompression surgery ameliorate the outcome in severe cases that do not show improvement with medical therapy, we conclude that decompression surgery, performed for the right indication, by the most skilful surgeons, might be effective in preventing sequelae (Table V).Reference McNeill7, Reference Gantz, Rubinstein, Gidley and Woodworth8, Reference Giancarlo and Mattucci27, Reference Brown55, Reference Yanagihara, Hato, Murakami and Honda86, Reference Fish and Esslen97, Reference May, Klein and Taylor98
Table V Outcome of surgery versus no surgery in patients with severe palsy or total paralysis
*Numbers not available
Conclusion
In view of these results, the probable pathogenesis and, in particular, the severe morbidity of permanent sequelae, antivirals can be crucial. They should be prescribed in combination with steroids in the event of severe deficit and for elderly patients. In cases of complete paralysis with no sign of recovery, and electrophysiological confirmation of a high chance of non-recovery, decompression might be indicated. Patients should be informed about the possibility of this treatment option.
