Functional endoscopic sinus surgery for chronic rhinosinusitis

Abstract

Background

This is an update of a Cochrane Review first published in The Cochrane Library in Issue 3, 2006.

Rhinosinusitis is a well‐recognised clinical syndrome affecting patients of all ages and gender. Functional endoscopic sinus surgery (FESS) has now become a well‐established strategy, comprising several techniques, for the treatment of chronic rhinosinusitis refractory to medical treatment.

Objectives

The aim of this review was to assess the effectiveness of FESS as a treatment for patients with chronic rhinosinusitis.

Search methods

We searched the Cochrane Ear, Nose and Throat Disorders Group Trials Register; the Cochrane Central Register of Controlled Trials (CENTRAL); PubMed; EMBASE; CINAHL; Web of Science; BIOSIS; mRCT and additional sources for published and unpublished trials. The date of the most recent search was 18 November 2008.

Selection criteria

Randomised controlled trials. Inclusion criteria were any of the following criteria singly or in combination: patients with chronic rhinosinusitis diagnosed by a health professional; patients with sinusitis symptoms for more than 12 weeks; endoscopic evidence of sinusitis or radiological evidence of sinusitis. Exclusion criteria were immune suppression; cystic fibrosis; Wegener's disease; previous sinus surgery or sinonasal malignancy.

Data collection and analysis

All studies meeting the inclusion criteria underwent validity assessment and the two authors extracted data independently.

Comparisons were:

FESS versus medical treatment; 
 FESS versus conventional sinus surgery; 
 FESS + medical treatment versus medical treatment; 
 FESS + medical treatment versus conventional sinus surgery + medical treatment.

Main results

We included three randomised controlled trials involving 212 participants.

The evidence available does not demonstrate that FESS, as practised in the included trials, is superior to medical treatment with or without sinus irrigation in patients with chronic rhinosinusitis. A middle meatal antrostomy fashioned by FESS was also not shown to be superior to an inferior meatal antrostomy formed by traditional sinus surgery techniques, although the small sample size in the study does not exclude a type II error.

In one study there was a relapse rate of 2.4% in the FESS and sinus irrigation group compared to 5.6% in the sinus irrigation only group. The relapse rates were not mentioned in the other studies.

There were no major complications, such as orbital injury or cerebrospinal fluid leak, reported in any of the included trials.

Authors' conclusions

FESS as currently practised is a safe surgical procedure. The limited evidence available suggests that FESS as practised in the included trials has not been demonstrated to confer additional benefit to that obtained by medical treatment (+/‐ sinus irrigation) in chronic rhinosinusitis. More randomised controlled trials comparing FESS with medical and other treatments, with long‐term follow up, are required.

Plain language summary

Functional endoscopic sinus surgery (FESS) for chronic rhinosinusitis

Rhinosinusitis is a common and well‐recognised clinical syndrome affecting patients of all ages and gender. Functional endoscopic sinus surgery (FESS) is now a well‐established strategy, which comprises several techniques, for the treatment of chronic rhinosinusitis which has not responded to medical treatment. FESS is a set of minimally invasive surgical techniques which allow direct visual examination and opening of the sinuses.

Three randomised controlled trials, involving 212 participants, met the inclusion criteria for this review. The evidence available does not demonstrate that FESS, as practised in the included trials, is superior to medical treatment with or without sinus irrigation in patients with chronic rhinosinusitis. There were no major complications in any of the included trials and FESS appears to be a safe procedure. More randomised controlled trials comparing FESS with medical and other treatments, with long‐term follow up, are required.

Background

This is an update of a Cochrane Review first published in The Cochrane Library in Issue 3, 2006.

The normal physiological functioning of the sinuses depends on patency of the osteomeatal unit, normal mucociliary transport and normal quantity and quality of secretions. A popular hypothesis for the development of chronic rhinosinusitis is that environmental factors, such as allergens, viruses or air pollutants, stimulate the epithelium to induce local inflammation of the sinus mucosa. The resulting mucosal oedema leads to ostial obstruction and retention of secretions followed by bacterial proliferation. In response to inflammation, the lining epithelium may become metaplastic and ciliary dysfunction ensues, perpetuating the condition. Various local factors such as nasal polyps, adenoid vegetations, dental infections and sinonasal tumours can predispose to sinusitis. A wide variety of systemic factors may contribute to the pathogenesis of chronic rhinosinusitis including allergy, cystic fibrosis, primary ciliary dyskinesia and immune deficiency (Naclerio 2001).

Rhinosinusitis is a well‐recognised clinical syndrome affecting patients of all ages and gender. Sinusitis is defined as a condition manifested by inflammation of the mucous membranes of the nasal cavity and paranasal sinuses, fluids within these cavities and/or the underlying bone. Chronic rhinosinusitis is sinusitis lasting more than 12 weeks. Chronic rhinosinusitis is diagnosed by the presence of two or more of the following major factors: facial congestion/fullness, nasal obstruction, nasal discharge (purulent) or discoloured postnasal drainage, hyposmia/anosmia (smell disorder), or one major and two of the following minor factors: headache, halitosis, fatigue, dental pain, cough or ear pressure/fullness. The diagnosis is also made in the presence of purulent nasal drainage on clinical examination (Lanza 1997). In 2005, the European Academy of Allergology and Clinical Immunology (EAACI) revised the definition to include two or more of 1) blockage/congestion; 2) discharge/postnasal drip; 3) facial pain/pressure; 4) reduction or loss of smell, and either endoscopic evidence of polyps, oedema or mucopurulent discharge from the middle meatus and/or CT changes in the mucosa of sinuses or osteomeatal complexes (EAACI 2005). The definition was further revised in the European Position Paper on Rhinosinusitis (EPOS) to include the presence of nasal obstruction or nasal discharge as a prerequisite to the diagnosis of chronic rhinosinusitis in addition to one or more other symptoms, as highlighted above (EPOS 2007).

Rhinosinusitis is a very common disorder. It is estimated that it affects more than 30 million Americans of all ages (NIH Data Book 1990). A survey of 1200 households in Nottingham, UK revealed that 13.7% had rhinosinusitis in the previous year (Jones 1998).

Bacteria can be recovered in most cases of chronic rhinosinusitis, most commonly consisting of Staphylococcus species, anaerobes and, in some cases, gram‐negative bacteria. Increasing trends towards bacterial resistance have been identified in chronic rhinosinusitis (Bhattacharyya 2002). Fungal rhinosinusitis is thought to be a spectrum of pathologic conditions associated with sinonasal inflammation that is related to the presence of fungi. It is broadly classified into extramucosal (non‐invasive) and invasive forms (Dhong 2001). Naylor suggests a role for fungi in the pathogenesis of all cases of chronic rhinosinusitis (Naylor 2000).

Medical therapy is the primary treatment modality for patients with chronic rhinosinusitis. The EPOS document (2007) suggested detailed treatment regimens for patients with chronic rhinosinusitis (EPOS 2007). The recommended treatment(s) depend on the severity of symptoms measured on a visual analogue scale (VAS) and the presence or absence of nasal polyposis. In moderate/severe cases with a VAS score greater than three, it is recommended that patients are given topical steroid sprays (drops in the presence of polyposis), nasal douching and long‐term treatment with antibiotics (macrolides). A short course of oral steroids is to be given initially before this treatment in patients with nasal polyposis presenting with severe symptoms (VAS score between 7 and 10). It is also recommended that a CT scan of the sinuses is performed if symptoms persist for more than three months prior to surgery (EPOS 2007). 

A Cochrane Review of the use of saline irrigation for chronic rhinosinusitis concluded that there is evidence that this treatment relieves symptoms, helps as an adjunct to treatment and is well‐tolerated by the majority of patients. While there is no evidence that saline is a replacement for standard therapies, the addition of topical nasal saline is likely to improve symptom control in patients with persistent sino‐nasal disease. No recommendations can be made regarding specific solutions, dosage or delivery. There were no significant side effects reported in trials (Harvey 2007).

Conventional sinus surgical techniques used to treat chronic sinusitis included antral lavage, external, intranasal and transantral ethmoidectomy, external frontal sinus surgery and the Caldwell‐Luc procedure (Kennedy 2001). However, over the past two decades the surgical management of rhinosinusitis has completely changed. This is due to technical advances in endoscopic systems and the recognition of the importance of normal sinus function of mucociliary flow and ventilation through the anatomical ostia. Functional endoscopic sinus surgery (FESS) is a set of minimally invasive techniques in which sinus air cells and ostia are opened under direct visualisation. The goal of this procedure is to restore sinus ventilation and normal function (Stammberger 1991).

The relative risks of sinus surgery have been a subject of controversy for many years. In 1912, Mosher stated that intranasal ethmoidectomy is one of the most dangerous of all surgical operations (Mosher 1912). In the modern endoscopic era, major and devastating complications continue to occur from time to time. Complications related to FESS include bleeding, orbital haematoma, damage to intraorbital structures, epiphora (watery eyes), loss of vision, cerebrospinal fluid leak, damage to intracranial structures and death. However, several large series quote a very low complication rate suggesting that this procedure can be done safely (Jones 1995). Stankiewicz has shown the importance of surgical experience in reducing the risk of complications from endoscopic sinus surgery (Stankiewicz 1989; Stankiewicz 1991).

FESS has now become well‐established for the treatment of chronic rhinosinusitis refractory to medical treatment. Enthusiasm for FESS, engendered by an abundance of reports of short‐term success, has been justified more recently by the publication of long‐term postoperative results which show a continued trend towards subjective improvement of symptoms in most patients (Richards 1999). There is, however, a conspicuous lack of good scientific evidence of the comparative efficacy of this intervention.

Objectives

The aim of this review was to assess the effectiveness of functional endoscopic sinus surgery as a treatment for patients with chronic rhinosinusitis.

Methods

Criteria for considering studies for this review

Types of studies

Randomised controlled trials.

Types of participants

Inclusion criteria

Any of the criteria below singly or in combination.

• Patients with chronic rhinosinusitis diagnosed by a health professional

• Patients with sinusitis symptoms for more than 12 weeks

• Endoscopic evidence of sinusitis

• Radiological evidence of sinusitis

Exclusion criteria

• Immune suppression

• Cystic fibrosis

• Wegener's disease

• Previous sinus surgery

• Sinonasal malignancy

Types of interventions

Functional endoscopic sinus surgery solely or as an adjunct treatment compared with medical treatment alone or alternative types of sinus surgery (e.g. antral washout, intranasal antrostomy, intranasal and transantral ethmoidectomy, external ethmoidectomy, frontal sinus procedures, Caldwell‐Luc procedure etc.), with or without medical treatment.

Types of outcome measures

Primary outcomes

The primary outcome measure was a global change in clinical status (e.g. cured, much improved, worse etc.) or a reduction in symptoms score.

Secondary outcomes

Secondary outcome measures included:

• a change in nasal endoscopic findings;

• documented radiological change in the appearance of the paranasal sinuses;

• a change in the microbiological flora of the nasal/paranasal sinus secretions (bacteriological cure and relapse rates); and

• use of postoperative medical treatment.

Adverse effects/complications (complication rates were calculated where applicable to facilitate comparison of treatments).

Search methods for identification of studies

We conducted systematic searches for randomised controlled trials. There were no language, publication year or publication status restrictions. The date of the last search was 18 November 2008.

Electronic searches

We searched the following databases:

• the Cochrane Ear, Nose and Throat Disorders Group Trials Register;

• the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2008, Issue 4);

• PubMed (1950 onwards);

• EMBASE (1974 onwards);

• CINAHL (1982 onwards);

• AMED (1985 onwards);

• ISI Web of Science;

• Biological Abstracts (BIOSIS);

• Scopus;

• LILACS;

• KoreaMed;

• IndMed;

• PakMediNet;

• mRCT (the metaRegister of Controlled Trials); and

• Google Scholar.

Subject strategies for databases were modelled on the search strategy designed for CENTRAL. Where appropriate, subject strategies were combined with adaptations of the highly sensitive search strategy designed by the Cochrane Collaboration for identifying randomised controlled trials and controlled clinical trials (as described in The Cochrane Handbook for Systematic Reviews of Interventions Version 5.0.1, Box 6.4.b. (Handbook 2008)).

CENTRAL search strategy

(MeSH terms appear in upper‐case and are exploded. Free text terms appear in lower‐case).

#1 SINUSITIS 
 #2 rhinosinusitis 
 #3 nasosinusitis 
 #4 sinusitis 
 #5 pansinusitis 
 #6 ethmoiditis 
 #7 antritis 
 #8 sphenoiditis 
 #9 (kartagener* near syndrome) 
 #10 (inflamm* near sinus*) 
 #11 (#1 or #2 or #3 or #4 or #5 or #6 or #7 or #8 or #9 or #10) 
 #12 CHRONIC DISEASE 
 #13 chronic* 
 #14 persist* 
 #15 (#12 or #13 or #14) 
 #16 (#11 and #15) 
 #17 ENDOSCOPY 
 #18 endoscop* 
 #19 uncinectomy 
 #20 antrostomy 
 #21 antrotomy 
 #22 ethmoidectomy 
 #23 sphenoidotomy 
 #24 SURGERY 
 #25 (sinus* next surg*) 
 #26 fess 
 #27 (#17 or #18 or #19 or #20 or #21 or #22 or #23 or #24 or #25 or #26) 
 #28 (#16 and #27) 
 #29 SINUSITIS [su] 
 #30 (#15 and #29) 
 #31 (#28 or #30)

Search strategies for other key databases including PubMed are shown in Appendix 1.

Searching other resources

We scanned reference lists of identified studies for further trials. We searched PubMed, TRIPdatabase, NLH ENT & Audiology Specialist Library and Google to retrieve existing systematic reviews possibly relevant to this systematic review, in order to search their reference lists for additional trials.

Data collection and analysis

Selection of studies

We performed verification of the eligibility of the studies identified by the search prior to data extraction. The two authors independently scanned titles and abstracts (when available) of all trials identified. We excluded articles that clearly did not meet the inclusion criteria. We obtained the full articles for studies that appeared to meet the inclusion criteria or where there was insufficient data in the title or abstract to make a decision. The authors had no disagreement regarding the eligibility of studies. We recorded studies excluded at the outset as well as at subsequent stages in the 'Characteristics of excluded studies' table and recorded the reason for exclusion.

Data extraction and management

All studies meeting the inclusion criteria underwent validity assessment and we extracted the data. The two authors extracted the data independently and synthesised data descriptively using an electronic data collection form.

For each trial we recorded the following:

• source of trial (published article, proceeding, unpublished data);

• year of publication, country of origin, setting, source of funding;

• demographic patient details;

• rhinosinusitis severity based on pre‐operative endoscopy, computed tomography (CT) scan or surgical findings;

• type of intervention with details;

• surgery: component surgical elements, surgical extent scores;

• antibiotics: generic details, dose and treatment duration;

• steroids: route/s, generic details, dose and treatment duration;

• type of outcome reported with details of method of assessment and time intervals.

Assessment of risk of bias in included studies

The two authors independently assessed the methodological quality of the included studies using the scheme described in the Cochrane Handbook for Systematic Reviews of Interventions.

Studies included in the review had four components of quality assessed:

1. Randomisation and allocation concealment

We recorded this on the data collection form as:

• adequate;

• unclear;

• inadequate; or

• not used.

2. Blinding

We recorded this as present or absent.

3. Reporting of participants by allocated group (intention‐to‐treat)

We assessed this as: A) Yes, B) No.

4. Follow up of participants (is there a clear explanation of withdrawals and drop‐outs in each treatment group?)

This was assessed as: A) Yes, B) No.

Data synthesis

We made the following primary comparisons:

• FESS versus medical treatment;

• FESS versus conventional sinus surgery;

• FESS + medical treatment versus medical treatment;

• FESS + medical treatment versus conventional sinus surgery + medical treatment.

Due to the very small numbers in the subgroups, no subgroup analysis was carried out.

We summarised studies as 'weighted treatment effects' as follows:

1. binary outcomes were expressed as a relative risk/odds ratio with 95% confidence intervals;

2. for continuous data the mean difference (with 95% confidence intervals) was given.

We explored heterogeneity among the studies by looking into types of participants, interventions, outcome measures used and time intervals.

Results

Description of studies

In total, 2159 abstracts were examined when we originally conducted this review in 2006. We identified nine potential studies. These included seven randomised controlled trials and two controlled trials. One of the randomised controlled trials was an unpublished trial (Fairley 1993). Three randomised controlled trials, involving 212 participants, met the inclusion criteria for this review (see 'Characteristics of included studies' table). We conducted the searches again to update the review in November 2008. We retrieved 164 further references for assessment. No new studies suitable for inclusion in the review were identified. Two new studies were added to the 'Characteristics of excluded studies' table (see below).

The three studies included within this review have important differences in their study populations, the interventions being compared and methods of outcome assessment. All studies met the definition of chronic rhinosinusitis.

The study by Fairley 1993 was a randomised controlled trial comparing endoscopic middle meatal antrostomy with conventional inferior meatal antrostomy.

The study by Hartog 1997 was a randomised controlled trial comparing FESS with sinus irrigation and medical treatment with sinus irrigation and medical treatment only. The medical treatment was in the form of loracarbef 400 mg twice daily for 10 days from day of enrolment in study.

Ragab 2004 compared FESS with medical treatment and medical treatment alone. Only patients who had failed a six‐week course of Dexarhinaspray® (dexamethasone isonicotinate, tramazoline hydrochloride) (DRS) twice a day and alkaline nasal douche twice a day were enrolled in the study. Patients randomised to the FESS group were prescribed a two‐week course of erythromycin 500 mg twice a day, DRS and alkaline nasal douche. This was followed by a three‐month course of twice daily use of 100 µg (two sprays) of fluticasone propionate intranasal spray into each nostril and alkaline nasal douche. Further medical treatment was tailored to the patient's manifestations, which comprised a topical corticosteroid spray in most circumstances. Patients randomised to the medical treatment group received a 12‐week course of erythromycin, alkaline nasal douche and intranasal corticosteroid preparations. Erythromycin was prescribed as 500 mg twice a day for the first two weeks then 250 mg twice a day for ten weeks. Intranasal corticosteroid preparations, in patients with chronic rhinosinusitis but without polyposis, were given as DRS, two puffs into each nostril, twice daily, for two weeks, followed by a twice daily dose of 100 µg (two sprays) of fluticasone propionate spray into each nostril for ten weeks. On the other hand, patients suffering from chronic rhinosinusitis with polyposis received a 12‐week course of twice daily use of 400 µg of fluticasone propionate drops into each nostril. In addition, three patients with chronic rhinosinusitis and polyposis were prescribed a nine‐day course of oral prednisolone tablets, 30 mg for three days, 20 mg for three days, and 10 mg for three days after failure of the above regimen to control their manifestations. After that, the medical treatment was tailored to the patient's manifestations.

A global improvement in symptoms was the primary outcome measure in one study (Hartog 1997). A symptom score was the primary outcome measure in the other two (Fairley 1993; Ragab 2004).

Four randomised controlled trials and two controlled trials were excluded. The randomised controlled trial by Venkatachalam 2002 comparing FESS and conventional sinus surgery for the treatment of chronic rhinosinusitis was excluded for a number of reasons. There were contradictory statements about the duration of follow up. The abstract stated the follow up was for a mean of 19.2 months (range 15 to 33 months). In the full text, the author states that the response to treatment was evaluated at three months after surgery. Moreover, the details of medical treatment for both groups were not mentioned. The studies by Penttila 1994 and Penttila 1997 were both excluded as there was a history of previous sinus surgery in some patients in both the treatment and control groups. The study by Blomqvist 2001 was excluded as an inclusion criterion was the presence of nasal polyposis only and the presence of any of the symptoms of chronic rhinosinusitis was not stipulated. Two non‐randomised studies were excluded. Arnes 1985 compared middle and inferior meatal antrostomy. However, a FESS technique was not used and the methodology was not clear. Ramadan 1999 enrolled children with chronic rhinosinusitis. All included children had failed a minimum of 24 weeks of treatment with an appropriate oral antibiotic as well as topical or oral decongestants. Children were allocated to either endoscopic sinus surgery or adenoidectomy in a non‐randomised fashion.

Following the update searches in November 2008, we excluded a further two studies. We contacted the authors of a randomised controlled trial registered in 2006 and discovered that this had been terminated due to failure to recruit enough patients (Fokkens 2009). A trial by Abd El‐Fattah et al (Abd El‐Fattah 2008) compared endoscopic middle meatal antrostomy with endoscopic radical antrectomy (removal of mucosa of maxillary sinus). The authors of this trial concluded that endoscopic radical antrectomy with middle meatal antrostomy  was superior to middle meatal antrostomy alone in chronic hyperplastic maxillary sinusitis. However, this trial was excluded from the review as it did not compare FESS with an alternative treatment but adopted FESS techniques in both groups. Moreover, the inclusion and exclusion criteria in the trial were not clear and the authors used a non‐validated questionnaire as one of their outcome measures.

Risk of bias in included studies

The three included studies were randomised controlled trials and involved 212 participants. It was unclear whether allocation concealment was carried out in any of the trials. There was no blinding applied in any of the included studies. Intention‐to‐treat analysis was applied in two of the studies (Hartog 1997; Ragab 2004).

In the Fairley 1993 study, the number of patients enrolled in the study was less than the calculated desired sample size, therefore a type II error cannot be excluded. The types of antibiotics prescribed and the number of patients who had postoperative antibiotics were not specified.

Effects of interventions

Cure rates

The study by Fairley 1993 included 33 patients; 21 females and 12 males. The mean age (± SD) in the FESS group was 52 (±13.6) years and in the inferior meatal antrostomy group 45 (±13.0) years. All patients had surgery by the same surgeon. Follow‐up data were available for 29 patients (12 in the FESS group and 17 in the inferior meatal antrostomy group). There was no difference in the symptom scores at follow up, which ranged from six weeks to 12 months, with a median follow up of 12 months (weighted mean difference (WMD) 1.37; 95% confidence interval (CI) ‐3.77 to 6.51, P = 0.6).

Hartog 1997 included a total of 89 patients with chronic maxillary sinusitis. Seventy‐seven patients were available for evaluation (41 in the FESS, sinus irrigation and medical treatment group and 36 in the sinus irrigation only group). The mean age (± SD) in the FESS and sinus irrigation group was 35 (±13) years and 38 (±13.5) years in the sinus irrigation only group. The median follow up was 12 months. The intention‐to‐treat analysis showed a significant reduction in the symptoms of purulent nasal discharge and hyposmia in the FESS group. However, there was no significant difference between both groups in overall cure rates at the end of one year (odds ratio (OR) 1.63; 95% CI 0.58 to 4.53, P = 0.35).

Ragab 2004 randomised 90 patients to treatment with FESS and medical treatment (n = 45) or medical treatment alone (n = 45). There were 45 males and 45 females. The mean age (± SD) was 43 (±13) years. At 12 months follow up 78 patients were available for analysis; 40 patients were available for follow up in the FESS and medical treatment group and 38 patients were available for follow up in the medical treatment only group. There was no difference in the total symptom scores at the end of 12 months (WMD 1.20; 95% CI ‐11.89 to 14.29, P = 0.86). A subgroup analysis found no difference in symptom scores in the groups in patients with chronic rhinosinusitis with polyposis and those without polyposis. However, the small number of patients in the subgroups raises the possibility of a type II error.

Relapses

In the Hartog 1997 study there was a relapse rate of 2.4% in the FESS and sinus irrigation group compared to 5.6% in the sinus irrigation only group. The relapse rates were not mentioned in the other studies.

Adverse effects

No major complications, such as orbital injury or cerebrospinal fluid leak, were reported in any of the included trials. There were no complications related to FESS reported in the Hartog 1997 study. The minor complications rate in patients undergoing FESS in the Fairley 1993 and Ragab 2004 studies combined was 15.4%. The minor complications included epistaxis, sinus infections, stenosis of middle meatal antrostomy and intranasal synechiae. The complications rate of inferior meatal antrostomy was 17.6% and included intranasal synechiae, stenosis of antrostomy and neuralgia. Adverse events reported in patients using topical corticosteroid preparations included mild epistaxis in 5.3%. Adverse events due to oral antibiotics occurred in 18.3% of patients and included allergic reactions, gastrointestinal complaints, headaches and dizziness. These complications did not lead to discontinuation of the antibiotic treatment.

Discussion

Chronic rhinosinusitis is a common health problem that leads to frequent visits to primary care physicians and to ear, nose and throat specialists. Chronic rhinosinusitis is estimated to affect 5% to 15% of the urban population (Melen 1994). It contributes to a significant amount of healthcare expenditure due to direct costs arising from physician visits and antibiotics, as well as indirect costs related to absence from work and a general loss of productivity due to a decrease in life‐quality of those affected (Lanza 1997; Osguthorpe 2001).

FESS has become an established surgical strategy, comprising a number of specific techniques, in the treatment of patients with chronic rhinosinusitis refractory to medical treatment. Despite its wide use, there is still a paucity of evidence regarding the effectiveness of FESS when compared to medical treatment and more conventional sinus surgery techniques. There are a plethora of publications on the topic of FESS. A systematic review of the literature has demonstrated that the vast majority of these studies are cohort studies or case series (level III evidence). Only a handful of trials qualify as level I or II evidence. These, however, have methodological shortcomings. A comparison of the results of different trials of FESS for treatment of chronic rhinosinusitis is difficult for a number of reasons. The studies lack a single disease staging system, the FESS procedures differ and the outcome measures are not uniform. The latter precludes the use of meta‐analysis. FESS is not a standardised set of surgical steps as the extent and specific nature of the surgery is determined by those sinuses which are affected and how extensively they are involved (Stammberger 1991). Moreover, there has been an evolution of FESS techniques over the years including the use of powered instruments and a more aggressive approach to sinus dissections. The FESS technique currently practised in some centres is likely to be different from that introduced by Messerklinger more than three decades ago. Lund suggests that randomised controlled trials of FESS and other surgical techniques are not conceivable given the difficulties of performing randomised controlled trials for surgical procedures, and the ethical difficulty of 'sham' operations (Lund 2001). The authors of the current review believe there is room for well‐designed, multicentre, randomised controlled trials comparing conservative FESS techniques with more radical approaches of endoscopic sinus surgery. Further trials comparing current FESS techniques with optimal medical treatment are also feasible.

The evidence available does not demonstrate that FESS, as practised in the included trials, is superior to sinus irrigation in patients with chronic rhinosinusitis suffering from isolated maxillary sinusitis. A middle meatal antrostomy fashioned by FESS was also not shown to be superior to an inferior meatal antrostomy formed by traditional sinus surgery techniques, though the small sample size in Fairley's study (Fairley 1993) does not exclude a type II error. FESS was not found to be superior to medical treatment in chronic rhinosinusitis patients with or without polyposis at the end of one year. However, patients in the Ragab study (Ragab 2004) with and without polyps received different medical management, a point which adds to the heterogeneity of the studied population. Chronic rhinosinusitis in children differs from that in adults. Children are more at risk because of smaller sinus volumes and natural ostia, more frequent upper respiratory tract infections and adenoidal hypertrophy (Lusk 1997). We were not able to include any studies of children. One excluded trial (Ramadan 1999) studied children with chronic rhinosinusitis and compared FESS with adenoidectomy, however participants were allocated to groups in a non‐randomised fashion. The main outcome measure, a symptom questionnaire completed by parents or carers, did show FESS to be superior. Adenoidectomy, while a traditional surgical procedure which may have a role to play in the management of patients with chronic rhinosinusitis, cannot be described as primarily a sinus surgical procedure. It therefore remains unproved whether FESS is superior to traditional sinus surgery or other treatment strategies in children.

These studies do show that FESS is a safe surgical technique. None of the included trials reported major complications such as orbital injury or cerebrospinal fluid leak. However, important but uncommon side effects may not be detected in randomised controlled trials involving relatively small numbers of participants.

Authors' conclusions

Implications for practice.

FESS as currently practised is a safe surgical procedure. The limited evidence available suggests that FESS as practised in the included trials has not been demonstrated to confer additional benefit to that obtained by medical treatment (+/‐ sinus irrigation) in chronic rhinosinusitis.

Implications for research.

The trial by Ragab 2004 is the first to suggest that optimal medical treatment is equally effective as FESS in chronic rhinosinusitis patients at the end of one year. More randomised controlled trials comparing FESS with medical and other treatments with long‐term follow up are required. Trials in subpopulations of patients, for example children or patients with polyposis, are particularly required as the benefit of FESS may be more apparent in some of these groups.

Feedback

Dr Alexander Chester, 2 April 2008

Summary

For the recently published reasons noted below I suggest that the review be withdrawn. (Chester AC. Endoscopic sinus surgery and evidence‐based medicine: The gold standard requires gold. Otolaryngol Head Neck Surg. 2008 Mar;138:409).

Endoscopic Sinus Surgery and Evidence‐Based Medicine: The Gold Standard Requires Gold

The need to establish efficacy of chronic rhinosinusitis treatments using evidence‐based medicine (EBM) was well described in a recent Otolaryngology ‐ Head and Neck Surgery symposium issue.¹ The power of these evaluations by the Cochrane Library, in particular, to influence patients, practitioners, and policy is hard to overstate. Despite substantial efforts to select and synthesize appropriate studies for EBM analysis, the conclusions are occasionally problematic.

For instance, the Cochrane Library’s systematic review of endoscopic sinus surgery (ESS) concludes that the procedure “does not confer additional benefit to that obtained by medical treatment” in relieving the symptoms of chronic rhinosinusitis based on the studies selected.^{2 (page 2)} This conclusion stands as the only EBM assessment of ESS efficacy that I am aware of and is based on limited evidence.

Although approximately 200 observational studies generally describe a success rate greater than 85%, findings of the 3 randomized controlled trials^3‐5 selected for analysis by the Cochrane Library suggest, according to the reviewers, no advantage for ESS over medical treatment. However, the studies miss the mark.

The first study³ reported no differences in medical and surgical outcomes among groups not receiving initial medical therapy that included antibiotics, a generally accepted prerequisite for ESS. The second study⁴ compared symptom improvement in isolated maxillary sinusitis noted after ESS vs after saline rinses among patients randomized before antibiotics were administered. The third study⁵ (a thesis) compared 12 patients receiving functional endoscopic middle meatal antrostomy vs 17 patients receiving conventional intranasal inferior meatal antrostomy, noting symptom improvement in both groups but no differences between groups; 1‐year follow‐up data were available for 11 patients vs 9 patients, a sample size the author acknowledges as being too small to exclude a type II error.

There is insufficient evidence for any comment about the worth of ESS compared with medical treatment based on these 3 studies. One study⁵ does not compare ESS with medical treatment, and the other 2 studies^{3 4} do not analyze ESS results among patients who failed medical treatment, including antibiotic therapy.

The reluctance of practitioners to quickly integrate EBM into medical practice reflects, in part, a concern that some conclusions are not justified by the data. Furthermore, many believe in this case that the results of numerous carefully designed observational studies of ESS efficacy should have some relevance in the assessment of the procedure when the few randomized controlled trials do not clearly address the subject.⁶

References

1. Bellorini J, Doree C, Chamberlain I, Burton MJ. The Cochrane Ear, Nose and Throat Disorders Group. Otolaryngol Head Neck 2007; 137(4S):S55‐S60.

2. Khalil HS, Nunez DA. Functional endoscopic sinus surgery for chronic rhinosinusitis. Cochrane Database Syst Rev 2006; 3:CD004458

3. Ragab SM, Lund VJ, Scadding G. Evaluation of the medical and surgical treatment of chronic rhinosinusitis: a prospective, randomised, controlled trial. Laryngoscope 2004; 114:923‐930.

4. Hartog B, van Benthem PP, Prins LC, Hordijk GJ. Efficacy of sinus irrigation versus sinus irrigation followed by functional endoscopic sinus surgery. Ann Otol Rhinol Laryngol 1997; 106:759‐766.

5. Fairley JW. Correlation of nasal symptoms with objective findings and surgical outcome measurement [thesis]. London: University of London, 1993.

6. Concato J. Observational versus experimental studies: what’s the evidence for a hierarchy? NeuroRx 2004; 1:341‐347.

Alexander C. Chester, MD 
 Georgetown University Hospital 
 Washington DC

Reply

Authors of systematic reviews in The Cochrane Library adopt a rigorous and pre‐specified approach to selecting trials for inclusion those reviews.

At the time of publication of the review (2006), the three included trials were the only ones that qualified for inclusion. This reflects the paucity of randomised controlled trials (RCTs) comparing FESS with other forms of treatment for chronic rhinosinusitis (CRS). We have qualified our statement about efficacy of FESS by "as practised in the included trials". Observational studies (level III evidence) are not currently included in the vast majority of Cochrane Reviews.  We have referred to the difficulties of conducting RCTs for surgical procedures like FESS. In our introduction, we have referred to the numerous short and long‐term observational studies that confirm favourable outcomes after FESS.¹ We are aware of the debate about the value of systematic reviews of well designed, non‐randomised, cohort and case control studies in general, and whether there is a place for such reviews in The Cochrane Library. This is particularly relevant in interventions where randomisation is not possible or ethical.

There is a consensus that FESS should only be offered to patients where optimal medical treatment has failed. The optimal medical treatment has changed over the years. The current recommendation for antibiotic treatment in the EPOS document is up to 12 weeks of antibiotics.² Historically, there has been no universal consensus on the duration of antibiotic treatment for patients with chronic rhinosinusitus (CRS). In the trial by Ragab et al (2004) the authors did not give antibiotics prior to randomisation. However, patients in the surgical arm of the trial received two weeks of antibiotics after the surgery. The medical arm received 12 weeks of antibiotics (again after randomisation). ³ What this trial has demonstrated is that a prolonged course of medical treatment (antibiotics and steroids) is as effective as surgery with a shorter course of medical treatment.

We will publish an update of our review in 2009. This will include reference to current recommendations for antibiotic treatments. It will be interesting to see if any RCTs have used a long course of antibiotics and steroid sprays prior to randomisation to the medical and surgical arms. We would not wish to prejudge the conclusions of the updated review. However, we will qualify any conclusions with reference to the current recommendations for optimal medical treatment.

References

1. Khalil H, Nunez DA. Functional endoscopic sinus surgery for chronic rhinosinusitis. Cochrane Database of Systematic Reviews 2006, Issue 3. Art. No.: CD004458. DOI: 10.1002/14651858.CD004458.pub2.

2. Fokkens W, Lund V, Bachert C, Clement P, Helllings P, Holmstrom M, Jones N, Kalogjera L, Kennedy D, Kowalski M, Malmberg H, Mullol J, Passali D, Stammberger H, Stierna P. EAACI Position Paper on Rhinosinusitis and Nasal Polyps Executive Summary. Allergy 2005; 60(5): 583–601.

3. Ragab SM, Lund VJ, Scadding G. Evaluation of the medical and surgical treatment of chronic rhinosinusitis: a prospective, randomised, controlled trial. Laryngoscope 2004; 114:923‐30.

Hisham S Khalil, MS, FRCS (ORL‐HNS), MD, FHEA 
 Consultant ENT Surgeon and Clinical Senior Lecturer 
 Derriford, Hospital, UK 
 Clinical Sub‐Dean, Peninsula College of Medicine and Dentistry, Plymouth, UK

Contributors

Alexander C. Chester, MD 
 Georgetown University Hospital 
 Washington DC 
 USA

Hisham S Khalil, MS, FRCS (ORL‐HNS), MD, FHEA 
 Consultant ENT Surgeon and Clinical Senior Lecturer 
 Derriford, Hospital, UK 
 Clinical Sub‐Dean, Peninsula College of Medicine and Dentistry, Plymouth 
 UK

Mr Desmond A Nunez 
 Consultant & Honorary Senior Lecturer 
 Academic Department of Otolaryngology 
 Southmead Hospital 
 Bristol 
 UK

Dr Alexander Chester, 7 July 2008

Summary

I certainly agree with Dr Khalil that only well designed randomized controlled trials should be used to assess the worth of a procedure. My point was not that adequate evidence exists elsewhere demonstrating the efficacy of ESS but, rather, that the evidence he and his co‐author marshaled did not demonstrate ESS to be ineffective.

The study noted in the author’s reply does not address the worth of surgery offered only when medical treatment fails. The surgical group in that study received two weeks of erythromycin following surgery while the medical group received three months of erythromycin. If a prolonged course of erythromycin was as successful as has previously been reported the medical group gains a significant advantage over the surgical group making surgery appear less worthwhile.

I do not think the conclusion offered by Drs. Khail & Nunez that ESS “does not confer additional benefit to that obtained by medical treatment” should stand until the subject is updated. Modifying the conclusion to read that ESS “has not been demonstrated to confer additional benefit to that obtained by medical therapy” reflects their findings more accurately. The first conclusion states that ESS has been judged by worthy evidence and found wanting, the other states the evidence is insufficient to pass judgement. Perhaps Dr Khalil could address this subject more directly in his reply.

Alexander C. Chester, MD 
 Georgetown University Hospital 
 Washington DC 
 USA

Reply

We are happy to rephrase the conclusion to read "FESS as practised in the included trials" has not been demonstrated to confer additional benefit to that obtained by medical therapy' and have done so.

Obviously, this may change with the new update.

Hisham Khalil 
 Desmond Nunez

Update of review July 2009

An updated search did not identify any new randomised controlled trials comparing FESS with medical treatment for chronic rhinosinusitis. There were no newly identified trials that administered a prolonged course of antibiotics prior to randomisation. We have updated the section on medical treatment of rhinosinusitis prior to considering surgery in the Background section, as recommended by the European Position Paper on Rhinosinusitis and Nasal Polyps, 2007.

Contributors

Alexander C. Chester, MD 
 Georgetown University Hospital 
 Washington DC 
 USA

Hisham S Khalil, MS, FRCS (ORL‐HNS), MD, FHEA 
 Consultant ENT Surgeon and Clinical Senior Lecturer 
 Derriford, Hospital, UK 
 Clinical Sub‐Dean, Peninsula College of Medicine and Dentistry, Plymouth 
 UK

Mr Desmond A Nunez 
 Consultant & Honorary Senior Lecturer 
 Academic Department of Otolaryngology 
 Southmead Hospital 
 Bristol 
 UK

What's new

Date	Event	Description
7 July 2009	New search has been performed	New searches were conducted in November 2008. No new studies could be included in the review. Two further studies were added to the excluded studies section.

History

Protocol first published: Issue 4, 2003
 Review first published: Issue 3, 2006

Date	Event	Description
13 August 2008	Feedback has been incorporated	Feedback from and response to Dr Alexander Chester incorporated in review.
14 May 2008	Amended	Converted to new review format.

Appendices

Appendix 1. Search strategies

PubMed	EMBASE (Ovid)	CINAHL (NLH Search 2.0)
#1 "Sinusitis"[Mesh] #2 rhinosinusitis [tiab] OR nasosinusitis [tiab] OR sinusitis [tiab] OR pansinusitis [tiab] OR ethmoiditis [tiab] OR ethmoiditis [tiab] OR sphenoiditis [tiab] #3 kartagener* [tiab] AND syndrome* [tiab] #4 inflamm* [tiab] AND sinus* [tiab] #5 #1 OR #2 OR #3 OR #4 #6 "Chronic Disease"[Mesh] #7 chronic [tiab] OR persis* [tiab] #8 #6 OR #7 #9 #5 AND #8 #10 "Endoscopy"[Mesh] #11 endoscop* [tiab] OR uncinectomy [tiab] OR antrostomy [tiab] OR antrotomy [tiab] OR ethmoidectomy [tiab] OR sphenoidotomy [tiab] #12 sinus AND surg* #13 FESS [tiab] #14 "Surgery"[Mesh] #15 #10 OR #11 OR #12 OR #13 OR #14 #16 #9 AND #15 #17 "Sinusitis/surgery"[Mesh] #18 #9 AND #17 #19 #16 OR #18	1 exp sinusitis/ 2 (rhinosinusitis or nasosinusitis or sinusitis or pansinusitis or ethmoiditis or ethmoiditis or sphenoiditis).tw. 3 (kartagener* and syndrome*).tw. 4 (inflamm* and sinus*).tw. 5 4 or 1 or 3 or 2 6 chronic disease/ or chronicity/ 7 Recurrent Disease/ 8 (chronic or persis* or repeat*).tw. 9 8 or 6 or 7 10 9 and 5 11 exp Endoscopy/ 12 (endoscop* or uncinectomy or antrostomy or antrotomy or ethmoidectomy or sphenoidotomy).tw. 13 (sinus and surg*).tw. 14 fess.tw. 15 exp *Surgery/ 16 11 or 13 or 12 or 15 or 14 17 16 and 10 18 Rhinosinusitis/su [Surgery] 19 18 or 17	1. exp SINUSITIS/ 2. (rhinosinusitis OR nasosinusitis OR sinusitis OR pansinusitis OR ethmoiditis OR ethmoiditis OR sphenoiditis).ti,ab 3.(kartagener* AND syndrome*).ti,ab 4.(inflamm* AND sinus*).ti,ab 5. 1 OR 2 OR 3 OR 4 6. exp CHRONIC DISEASE/ 7. (chronic OR persis*).ti,ab 8. 6 OR 7 9. 5 AND 8 10. exp CHRONIC SINUSITIS/ 11. 9 OR 10 12. exp ENDOSCOPIC SURGERY/ 13. (endoscop* OR uncinectomy OR antrostomy OR antrotomy OR ethmoidectomy OR sphenoidotomy OR fess).ti,ab 14. (sinus AND surg*).ti,ab 15. exp SURGERY/ 16. 12 OR 13 OR 14 OR 15 17. 11 AND 16 18. exp CHRONIC SINUSITIS/su [su=Surgery] 19. 17 OR 18
ISI Web of Science	Biological Abstracts (BIOSIS)	mRCT
#1 TS=(rhinosinusitis OR nasosinusitis OR sinusitis OR pansinusitis OR ethmoiditis OR ethmoiditis OR sphenoiditis) #2 TS=(kartagener* AND syndrome*) #3 TS=(inflamm* AND sinus*) #4 #3 OR #2 OR #1 #5 TS=(chronic OR persis*) #6 #5 AND #4 #7 TS=(endoscop* OR uncinectomy OR antrostomy OR antrotomy OR ethmoidectomy OR sphenoidotomy) #8 TS=(sinus AND surg*) #9 TS=fess #10 #9 OR #8 OR #7 #11 #10 AND #6	#1 TS=(rhinosinusitis OR nasosinusitis OR sinusitis OR pansinusitis OR ethmoiditis OR ethmoiditis OR sphenoiditis) #2 TS=(kartagener* AND syndrome*) #3 TS=(inflamm* AND sinus*) #4 #3 OR #2 OR #1 #5 TS=(chronic OR persis*) #6 #5 AND #4 #7 TS=(endoscop* OR uncinectomy OR antrostomy OR antrotomy OR ethmoidectomy OR sphenoidotomy) #8 TS=(sinus AND surg*) #9 TS=fess #10 #9 OR #8 OR #7 #11 #10 AND #6	(rhinosinusitis OR nasosinusitis OR sinusitis OR pansinusitis OR ethmoiditis OR ethmoiditis OR sphenoiditis) AND (chronic or persis%) AND (endoscop% OR uncinectomy OR antrostomy OR antrotomy OR ethmoidectomy OR sphenoidotomy)

Data and analyses

Comparison 1. FESS + medical +/‐ sinus irrigation versus medical +/‐ sinus irrigation.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Symptom score	1	78	Mean Difference (IV, Fixed, 95% CI)	1.20 [‐11.89, 14.29]
2 Global improvement	1	77	Odds Ratio (M‐H, Fixed, 95% CI)	1.63 [0.58, 4.53]

1.1. Analysis.

Comparison 1 FESS + medical +/‐ sinus irrigation versus medical +/‐ sinus irrigation, Outcome 1 Symptom score.

1.2. Analysis.

Comparison 1 FESS + medical +/‐ sinus irrigation versus medical +/‐ sinus irrigation, Outcome 2 Global improvement.

Comparison 2. FESS versus intranasal antrostomy.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Symptom score	1	29	Mean Difference (IV, Fixed, 95% CI)	1.37 [‐3.77, 6.51]

2.1. Analysis.

Comparison 2 FESS versus intranasal antrostomy, Outcome 1 Symptom score.

Characteristics of studies

Characteristics of included studies [ordered by study ID]

Fairley 1993.

Methods	Randomised Study duration = 1 year Type of trial = parallel design Blinding = absent Follow up = 6 to 52 weeks Drop‐outs = 4
Participants	Inclusion criteria: Symptoms of sinusitis Rhinoscopic evidence of nasal abnormality, and/or Sinus radiograph evidence of sinusitis (opacity, or mucosal thickening of antrum, ethmoid, frontal or sphenoid sinuses) Failed medical treatment with oral antibiotics, topical steroid sprays for 6 weeks and antral washouts Exclusion criteria: Pregnancy Untreated sinusitis Complicated sinusitis Untreated deviation of nasal septum Previous sinus surgery Malignant diseases of the nose and sinuses Inability or unwillingness to comply with trial procedures Setting: tertiary referral centre Number of participants = 33 Demographics: FESS group: age = 52 (+/‐ 13.6 years SD), INA group = 45 (+/‐13 years SD) Gender ratio F:M = 10:4 (FESS) and 11:8 (INA)
Interventions	Functional endoscopic sinus surgery (FESS) or intranasal antrostomy
Outcomes	Nasal symptom scores
Notes	—
Risk of bias
Bias	Authors' judgement	Support for judgement
Allocation concealment?	Unclear risk	B ‐ Unclear

Hartog 1997.

Methods	Randomised Study duration = 3 years Type of trial = parallel design Blinding = absent Follow up = 12 to 52 weeks Drop‐outs = 22
Participants	Inclusion criteria: Maxillary sinusitis At least 2 of the following 3 symptoms: purulent rhinorrhoea, nasal obstruction, headache Sinus radiograph evidence of maxillary sinusitis (complete opacity, fluid level or mucosal swelling at least 1/2 way to mediolateral line of maxillary sinus) Stopped antibiotics for at least 4 weeks Symptoms for at least 3 months Written informed consent Exclusion criteria: Frontal, ethmoidal or sphenoid sinus disease or ethmoidal polyps Chronic diseases Immunodeficiency Previous sinus surgery Setting: multicentre trial in 13 hospitals Number of participants = 89 Demographics: Sinus irrigation: age = 38 (+/‐ 13.5 years SD); 22 males, 23 females Sinus irrigation + FESS: age = 35 (+/‐ 13 years SD); 22 males, 22 females
Interventions	Sinus irrigation or sinus irrigation followed by functional endoscopic sinus surgery Both groups completed a 10‐day course of loracarbef, 400 mg twice a day
Outcomes	I. Global Cure Late cure Failure Relapse Recurrence at 52 weeks II. Patient symptoms III. Mucosal swelling and purulency under middle turbinate on nasal endoscopy at 2, 6, 12 and 52 weeks IV. Sinus radiograph
Notes	—
Risk of bias
Bias	Authors' judgement	Support for judgement
Allocation concealment?	Unclear risk	B ‐ Unclear

Ragab 2004.

Methods	Randomised Study duration = 2 years Type of trial = parallel design Blinding = absent Follow up = 12 months Drop‐outs = 12
Participants	Inclusion criteria: 8 weeks or more of manifestations of CRS 2 major or one major and 2 minor symptoms (major: nasal congestion/obstruction, nasal discharge, facial pain or pressure, headache, olfactory disturbance; minor: fever, halitosis or 4 episodes per year of recurrent acute rhinosinusitis each lasting at least 10 days in association with persistent changes on CT for weeks after medical therapy without intervening acute infection) Exclusion criteria: Pregnancy Lactation Significant psychological problems Inability to comply with study protocol Children under 18 years of age Systemic diseases affecting the nose (e.g. Wegener's granulomatosis, sarcoid, primary ciliary dyskinesia, cystic fibrosis, and acute upper or lower respiratory tract infections within 2 weeks before the inclusion visit) Use of systemic corticosteroids within 4 weeks before the inclusion visit Systemic diseases preventing participation in the study Medical or surgical treatments influencing the study Setting: tertiary referral centre Number of participants = 90 Demographics: Age = 43 (+/‐ 13 years SD), 45 male, 45 female
Interventions	FESS (Messerklinger technique) + medical treatment (2‐week course of twice‐daily use of 500 mg erythromycin, Dexarhinaspray and alkaline nasal douche). This was followed by a 3‐month course of twice‐daily use of 100 ug (2 sprays) of fluticasone propionate intranasal spray into each nostril and alkaline nasal douche. Medical treatment (12‐week course of erythromycin; 500 mg twice a day for 2 weeks then 250 mg twice a day for 10 weeks, alkaline nasal douche, and intranasal corticosteroid preparations; Dexarhinaspray 2 puffs twice‐daily for 2 weeks then 10 weeks of fluticasone 100 ug twice daily for 10 weeks, for CRS with polyposis patients, fluticasone drops, 400 ug were used instead of spray for 12 weeks)
Outcomes	I. Global Asymptomatic Distinct improvement Slight improvement Unchanged Worse
Notes	—
Risk of bias
Bias	Authors' judgement	Support for judgement
Allocation concealment?	Unclear risk	B ‐ Unclear

CRS = chronic rhinosinusitis 
 FESS = functional endoscopic sinus surgery 
 INA = intranasal antrostomy

Characteristics of excluded studies [ordered by study ID]

Study	Reason for exclusion
Abd El‐Fattah 2008	ALLOCATION: Randomised controlled trial PARTICIPANTS: Patients who fulfilled the clinical, radiological and histopathological criteria for chronic, hyperplastic, eosinophilic sinusitis INTERVENTIONS: Endoscopic middle meatal antrostomy versus endoscopic radical antrectomy (removal of mucosa of maxillary sinus). Did not compare FESS with an alternative treatment but adopted FESS techniques in both groups.
Arnes 1985	ALLOCATION: Not clear PARTICIPANTS: Included patients with chronic rhinosinusitis INTERVENTIONS: FESS technique not used
Blomqvist 2001	ALLOCATION: Randomised trial PARTICIPANTS: Included patients with nasal polyps and not chronic rhinosinusitis symptoms
Fokkens 2009	ALLOCATION: Randomised controlled trial Note: trial was terminated due to failure to recruit enough patients (personal communication)
Penttila 1994	ALLOCATION: Randomised trial, not blinded PARTICIPANTS: Included patients with previous sinus surgery in both treatment and control groups
Penttila 1997	ALLOCATION: Randomised trial, not blinded PARTICIPANTS: Included patients with previous sinus surgery in both treatment and control groups
Ramadan 1999	ALLOCATION: Non‐randomised study (controlled clinical trial)
Venkatachalam 2002	ALLOCATION: Not clear PARTICIPANTS: Included patients with previous sinus surgery INTERVENTIONS: Details of medical treatment for both groups not mentioned. Contradictory statements about duration of follow up.

FESS = functional endoscopic sinus surgery

Contributions of authors

Both authors contributed equally to all review tasks.

Sources of support

Internal sources

• North Bristol NHS Trust, UK.

• University of Bristol, UK.

• University of Plymouth, UK.

• Plymouth Hospitals NHS Trust, UK.

External sources

• No sources of support supplied

Declarations of interest

HK has been funded to speak at local meetings by Merck Sharp & Dohme.

DAN has been funded to speak at local meetings and to attend international conferences by UCB Pharma and Schering‐Plough. In addition he is the convenor of an annual FESS course supported in part by Storz. He organises regional meetings of otolaryngologists which have received sponsorship in addition to any of the above from Xomed‐Medtronic and Merck Sharp & Dohme.

New search for studies and content updated (no change to conclusions)