Clinical UM Guideline

This document addresses the use of functional endoscopic sinus surgery (FESS), an endoscopic surgical procedure used to treat various conditions of the nasal sinuses, including but not limited to chronic sinusitis.

Note: Please see the following documents for related information:

• CG-SURG-18 Septoplasty
• CG-SURG-73 Balloon Sinus Ostial Dilation
• SURG.00089 Self-Expanding Absorptive Sinus Ostial Dilation
• SURG.00132 Drug-Eluting Devices for Maintaining Sinus Ostial Patency

Note: For a high-level overview of this document, please see “Summary for Members and Families” below.

Medically Necessary:

Functional endoscopic sinus surgery (FESS) is considered medically necessary when any one of the following circumstances is present:

1. Suspected tumor seen on imaging, physical examination, or endoscopy; or
2. Suppurative (pus forming) complications, including but are not limited to:
   1. Subperiosteal abscess; or
   2. Brain abscess;
      or
3. Chronic polyposis with symptoms unresponsive to medical therapy; or
4. Allergic fungal sinusitis; or
5. Mucocele causing chronic sinusitis; or
6. Recurrent sinusitis that triggers or aggravates pulmonary disease, such as asthma or cystic fibrosis; or
7. Uncomplicated sinusitis (for example, sinusitis confined to the paranasal sinuses without adjacent involvement of neurologic, soft tissue, or bony structures) when criteria below are met based on the treated individual’s age group:
   1. Adults (18 and older) who meet all (a, b, and c) of the following criteria:
      1. Either of the following:
         1. Four or more documented episodes of acute rhinosinusitis (for example, up to 4 weeks duration) in 1 year; or
         2. Chronic sinusitis (for example, greater than 12 weeks duration) that interferes with lifestyle;
            and
      2. Maximal medical therapy has been attempted, as indicated by all of the following:
         1. Antibiotic therapy; and
         2. Trial of inhaled steroids; and
         3. Nasal lavage; and
         4. Allergy testing (if symptoms are consistent with allergic rhinitis and have not responded to appropriate environmental controls and pharmacotherapy [antihistamines, intranasal corticosteroids, leukotriene antagonists, etc.]);
            and
      3. Abnormal findings from diagnostic work-up, as indicated by any one of the following:
         1. CT findings suggestive of obstruction or infection for example, but not limited to, air fluid levels, air bubbles, significant mucosal thickening, pansinusitis, or diffuse opacification; or
         2. Nasal endoscopy findings suggestive of significant disease; or
         3. Physical exam findings suggestive of chronic or recurrent disease (for example, mucopurulence, erythema, edema, inflammation);
            or
   2. Children and adolescents 17 years old or younger who meet both (a and b) of the following criteria:
      1. Persistent symptoms of chronic rhinosinusitis (for example, nasal obstruction, discharge, cough, or facial pressure) despite maximal therapy consisting of:
         1. Saline nasal irrigation; and
         2. Intranasal corticosteroids; and
         3. Objective evidence of disease including abnormal sinus CT findings;
            and
      2. First line surgical adenoidectomy has been completed.
         or
8. Fungal mycetoma; or
9. Persistent sinus symptoms following any prior sinus surgery; or
10. Cerebrospinal fluid rhinorrhea; or
11. Encephalocele; or
12. Posterior epistaxis (relative indication); or
13. Persistent facial pain after other causes ruled out (relative indication); or
14. Cavernous sinus thrombosis caused by chronic sinusitis.

Nasal or sinus cavity debridement following functional endoscopic sinus surgery (FESS) is considered medically necessary for any of the following circumstances:

1. Twice during the first 30 days postoperatively; or
2. Postoperative loss of vision or double vision; or
3. Evidence of cerebrospinal fluid leak such as rhinorrhea; or
4. When prompted by physical obstruction of the sinus opening related to:
   1. Nasal polyps unresponsive to oral or nasal steroids; or
   2. Documented presence of papilloma, carcinoma or other neoplasm; or
   3. Allergic fungal sinusitis.

Not Medically Necessary:

Functional endoscopic sinus surgery (FESS) is considered not medically necessary when the criteria above are not met.

Nasal or sinus cavity debridement following functional endoscopic sinus surgery (FESS) is considered not medically necessary when the criteria above are not met, including additional post-surgical debridement beyond 30 days post-procedure.

This document describes clinical studies and expert recommendations, and explains when functional endoscopic sinus surgery (FESS) is clinically appropriate. The following summary does not replace the medical necessity criteria or other information in this document. The summary may not contain all of the relevant criteria or information. This summary is not medical advice. Please check with your healthcare provider for any advice about your health.

Key Information

FESS is a procedure used to treat long lasting or severe sinus problems when medical care has not helped enough. A doctor uses small tools and a camera passed through the nose to remove blocked or diseased tissue and open the sinus passages. This can improve drainage and breathing, and lessen or prevent sinus congestion and infections. FESS is less invasive than older surgery methods and often has faster recovery and fewer complications. It may be used to treat chronic sinus infections, nasal polyps, tumors, or other serious sinus conditions. However, it is usually considered only after trying medicines such as antibiotics or steroid sprays.

What the Studies Show

FESS works by surgically opening blocked sinus pathways so mucus can drain better and inflammation can improve. Studies show that both medical treatment and surgery can improve symptoms of chronic sinus problems. In some studies, surgery improved nasal blockage and reduced polyp size, but it did not always improve sense of smell. Other research found that surgery and medical care had similar results overall. Because of this, experts recommend trying full medical treatment first and using surgery when symptoms do not improve. FESS is generally safe, with low rates of serious complications. It can improve sinus symptoms and may help short term asthma symptoms in people who have both conditions. However, lung function does not always improve. Some people may need repeat surgery over time. Studies also show that combining FESS with other procedures does not greatly increase risk. For follow up care, cleaning the sinuses after surgery, called debridement, may reduce crusting in some cases, but it can cause more pain and does not clearly improve long term outcomes. Better studies are needed to know if frequent debridement improves health.

When is FESS Clinically Appropriate?

FESS may be clinically appropriate in these situations:

• A tumor is suspected based on imaging, exam, or scope findings; or
• Serious infections with pus, such as abscesses in the sinus or brain; or
• Chronic nasal polyps that do not improve with medical treatment; or
• Allergic fungal sinus disease; or
• A mucus filled cyst causing long term sinus problems; or
• Repeated sinus infections that worsen lung diseases such as asthma or cystic fibrosis; or
• Ongoing sinus symptoms with all of the following:
  • Frequent infections in 1 year or symptoms lasting more than 12 weeks; and
  • Treatment has been tried, including antibiotics, steroid sprays, nasal rinses, and allergy care when needed; and
  • Objective signs of disease on CT scan, endoscopy, or exam; or
  • Certain other serious conditions, such as fluid leaks from the brain, tissue protrusion into the sinus, blood vessel clots, or ongoing symptoms after prior sinus surgery.

For children, FESS may be clinically appropriate when all of the following are met:

• Ongoing symptoms despite nasal rinses and steroid sprays; and
• Objective findings on imaging; and
• Prior adenoid removal surgery has already been done.

When is this not Clinically Appropriate?

FESS is not clinically appropriate in scenarios other than those listed above. This is because studies show that many people improve with medical treatment alone, and surgery does not always lead to better outcomes. Postoperative sinus cleaning is not clinically appropriate beyond early recovery or without clear medical need. Studies show it may cause more pain and inconvenience and does not clearly improve long term results. Unnecessary or unproven tests or treatments can expose someone to risks without anticipated benefits.

(Return to Description)

The following codes for treatments and procedures applicable to this document are included below for informational purposes. Inclusion or exclusion of a procedure, diagnosis or device code(s) does not constitute or imply member coverage or provider reimbursement policy. Please refer to the member's contract benefits in effect at the time of service to determine coverage or non-coverage of these services as it applies to an individual member.

When services may be Medically Necessary when criteria are met:

When services are Not Medically Necessary:
For the procedure and diagnosis codes listed above when criteria are not met or for all other diagnoses not listed.

Summary

Functional endoscopic sinus surgery (FESS) is considered medically necessary for a range of serious or treatment-resistant sinus conditions. These include suspected tumors, severe infections with complications such as abscesses, chronic nasal polyps unresponsive to medical therapy, allergic fungal sinusitis, mucoceles, and recurrent sinusitis that worsens pulmonary diseases like asthma or cystic fibrosis. It is also indicated for specific structural or neurologic issues such as cerebrospinal fluid leaks, encephaloceles, cavernous sinus thrombosis, or persistent symptoms following prior sinus surgery. In uncomplicated sinusitis, FESS is appropriate only when strict criteria are met, including frequent or chronic symptoms, failure of maximal medical therapy such as antibiotics, steroids, nasal irrigation and objective evidence of disease on imaging, endoscopy, or physical exam. Pediatric FESS requires persistent symptoms despite medical therapy, objective findings, and prior adenoidectomy.

Postoperative nasal or sinus debridement after FESS is considered medically necessary in limited circumstances, such as within the first 30 days (typically up to two times), or when complications arise for example, vision changes, cerebrospinal fluid leak, or obstruction from polyps, tumors, or fungal disease. FESS related debridements are considered not medically necessary when the criteria are not met, including routine or prolonged postoperative debridement beyond 30 days without clear clinical indication. Overall, guidelines emphasize that surgery should generally follow unsuccessful medical management and be reserved for clearly defined clinical scenarios.

Discussion

Functional Endoscopic Sinus Surgery (FESS)

FESS is the most commonly used surgical technique to treat medically unresponsive chronic sinusitis and other serious conditions of the nasal sinuses that result in impaired sinus drainage. FESS uses small fiber optic tools to access the nasal sinuses through the nares to remove diseased tissue and bone. This may result in opened sinus passageways, improved mucus drainage, and promotion of healthy tissue growth.

Prior to the creation and adoption of FESS, the standard treatment method involved the creation of a surgical opening in the upper jaw above the front teeth. The use of FESS allows for a much less invasive and traumatic procedure, shorter surgery and healing times, less postoperative discomfort, and fewer surgical complications. FESS has become a generally accepted alternative to open sinus surgery for indications requiring access to a nasal sinus. These include evaluation or treatment of tumors, polyps, chronic rhinosinusitis (CRS), cerebrospinal fluid rhinorrhea, encephalocele, posterior epistaxis, allergic fungal sinusitis, and persistent facial pain after other causes ruled out.

Despite having been widely adopted, only a few controlled trials evaluating the use of FESS for various conditions have been published in the medical literature. One randomized controlled trial (RCT) by Blomqvist (2001) compared medical treatment for nasal polyps with surgery followed by medical treatment in 32 participants with a follow-up of 1 year. The authors reported that surgery reduced the polyp score and improved nasal obstruction symptoms, but did not help with hyposmia (reduced sense of smell). Another study by Penttila (1997) reported the results of a randomized study comparing FESS vs. the Caldwell-Luc (C-L) open procedure for the treatment of chronic maxillary sinusitis. Follow-up ranged from 5 to 9 years with 128 individuals responding. The authors reported that the outcomes for the FESS group were approximately equivalent to that in the C-L group.

A prospective, RCT of medical vs. surgical treatment of polypoid and nonpolypoid CRS is described by Ragab (2004). In this study, 90 people with CRS were randomized to either medical or surgical therapy with FESS. The study found that both the medical and surgical treatments for CRS significantly improved almost all subjective and objective parameters of CRS. The study found no significant difference between the two groups. The authors conclude that CRS should initially be treated with maximal medical therapy (including antibiotics and topical steroids) with surgical treatment being reserved for cases refractory to medical therapy.

Bitner (2021) performed a meta-analysis in which individuals were categorized as either having FESS or rhinoplasty alone or combined. Six of the studies reviewed provided information for further quantitative analysis and included 190 individuals who underwent FESS and rhinoplasty, 45 individuals who underwent FESS and 170 who underwent rhinoplasty. All participants were similar across all studies with mean age ranging from 24.5 and 40.6 years. The individuals that underwent combined surgery or FESS alone had a clinical diagnosis of CRS. Postoperative complications were observed in 23 of 190 (12.1%) combined cases, in 2 of 45 (4.4%) FESS cases and in 10 of 170 (5.9%) rhinoplasty cases. Major complications were defined as prolonging the hospital length of stay and/or required intervention. Major complications were observed in 11 (5.8%) combined cases, 0 (0%) FESS cases and 6 (3.5%) rhinoplasty cases. The researcher’s analysis indicated there was no associated increased risk in postoperative complications when combining surgeries compared to rhinoplasty. In addition, there were no major differences in reoccurrence of CRS symptoms, revision rate, or individual satisfaction.

Finally, a Cochrane review of FESS for the indication of CRS from July 2006 concluded:

The evidence available does not demonstrate that FESS, as practiced 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.

The American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS, (2015) and the American Academy of Allergy, Asthma, and Immunology practice parameter (AAAAI, 2014) recommend that medical therapy for CRS (with polyposis) be based on the individual’s clinical presentation. General recommendations include systemic antibiotics for 5-10 days for exacerbations, topical antibiotics for 3-6 weeks, and a short course of oral steroids. They also recommended that individuals who do not have significant nasal blockage should be treated with intranasal corticosteroids and nasal saline irrigation.

The AAAAI practice parameter offers guidance for evaluation of allergic fungal rhinosinusitis (AFRS). This condition should be suspected when there is persistent nasal congestion with thick discharge, nasal polyps, or facial pain. Other findings may include type I hypersensitivity to fungi by skin test or serum specific IgE, characteristic sinus CT findings (high attenuation areas and possibly bony erosion) or MRI results (central low signal on T1- and T2-weighted images and high signal intensity in areas of inflammation). Final confirmation of diagnosis for allergic fungal rhinosinusitis may occur with intraoperative histological findings such as eosinophilic mucin and fungal elements on pathology.

Evidence from a systematic review of 53 studies evaluating chronic rhinosinusitis with comorbid asthma (CRSwA) demonstrates that traditional CRS medical therapies including saline irrigation, intranasal corticosteroids, oral antibiotics, and oral corticosteroids, produce significant improvements in sinonasal-specific quality-of-life outcomes, particularly in individuals with CRS with nasal polyps (CRSwNP). However, individuals with comorbid asthma may experience less improvement in symptom scores compared to those CRS individuals without asthma (e.g., reduced improvement in SNOT-22 scores; adjusted odds ratio [OR], 0.13; 95% confidence interval [CI], 0.03-0.72). Limited evidence suggests potential sinonasal symptom improvement with macrolides or leukotriene receptor antagonists, although data are based on small cohorts. Oral corticosteroids can improve both sinonasal and asthma-related outcomes but require cautious use due to systemic adverse effects. Evidence supporting improvement in asthma-specific outcomes from medical CRS therapy is limited. Low grade evidence suggests that macrolides may provide modest benefit in small studies, while intranasal corticosteroids have not been shown to improve pulmonary function or asthma control. ESS provides consistent improvement in sinonasal symptoms and short-term asthma related outcomes, including reductions in asthma symptoms, exacerbations, medication use, and healthcare utilization. However, objective pulmonary function measures generally do not demonstrate significant improvement after surgery based on available data. Additionally, individuals with CRSwA have higher rates of revision ESS compared with CRS without asthma, with reported revision rates of approximately 20-30% over long-term follow-up. Overall, evidence supports ESS as an effective treatment for refractory CRS symptoms and short-term improvement in asthma control, but data are inconsistent regarding long-term asthma control and do not demonstrate reliable improvement in pulmonary function (Gill, 2023).

In June 2025, AAO-HNS published their latest Surgical Management of Chronic Rhinosinusitis Clinical Practice Guideline (CPG), which defined conditions related to rhinosinusitis (see Definitions section) and provided the following relevant recommendations:

Statement 1: Verification of Diagnosis and Assessment of Candidacy for Surgery
1A: The surgeon should verify an existing diagnosis of CRS to ensure established diagnostic criteria (signs and symptoms) from CPGs are met
AND
1B: The surgeon should assess candidacy for sinus surgery based on symptoms, disease characteristics, QOL, and prior medical or surgical therapy.
Evidence strength: Strong recommendation based on multiple CPGs and SRs.

Statement 2: No One-Size-Fits-All Regimen
The surgeon should not endorse or require a predefined, one‐size‐fits‐all regimen or duration of medical therapy (eg, antibiotics, steroids, antihistamines) as a prerequisite to sinus surgery for an adult with CRS.
Evidence strength: Recommendation based on RCTs and meta‐analyses that show variable quality in the types of medical therapeutics for the treatment of CRS.

Statement 3: Assessment Before Prescribing Antibacterial Therapy
The surgeon or their designee should not prescribe antibacterial therapy to an adult with CRS if significant or persistent purulent nasal discharge (anterior, posterior, or both) is absent on examination.
Evidence strength: Strong recommendation based on RCTs that are limited in number but demonstrate a preponderance of benefit over harm when limiting the indiscriminate use of antibiotics for CRS treatment.

Statement 4: Relative Benefits of Surgery or Medical Therapy Alone
The surgeon should identify patients with CRS that would benefit most from surgery and are least likely to benefit from continued medical therapy alone, such as those with CRS subtypes that include, but are not limited to, CRS with polyps, polyps with bony erosion, eosinophilic mucin, or fungal balls.
Evidence strength: Recommendation based on a limited number of RCTs and multiple observational studies that demonstrate consistent benefit over harm through avoidance of delays in care and disease progression when timely surgery is provided as part of an overall care plan; insufficient equipoise to pursue trials comparing medical therapy alone and surgery in cases of CRS with skull base erosion, eosinophilic mucin rhinosinusitis, allergic fungal rhinosinusitis (AFRS), or fungal ball due to concerns about disease progression and harm to surrounding anatomic structures.

Statement 5: Patient Education About Surgery and Long-Term Management
The surgeon or their designee should counsel patients before sinus surgery to establish realistic expectations, including the potential for chronicity or relapse, and the likelihood of long‐term medical management, taking into account their CRS subtype.
Evidence strength: Recommendation based on moderate quality evidence (levels B and C).

Statement 6: When to Offer Sinus Surgery
The surgeon should offer sinus surgery to an adult with CRS when the anticipated benefits exceed that of nonsurgical management alone, there is clarity regarding the anticipated outcomes, and the patient understands the expectation for long‐term disease management following surgery.
Evidence strength: Recommendation based on cohort studies and one RCT that support a preponderance of benefit over harm.

Statement 7: Imaging in Candidates for Sinus Surgery
For an adult who is a candidate for sinus surgery, the surgeon or their designee should obtain a CT scan with a fine‐cut protocol, if not already available, to examine the paranasal sinuses for surgical planning.
Evidence strength: Recommendation based on limited and mostly observational reports, surgeon preference, and availability of imaging with a majority of evidence of moderate quality and moderate correlation with surgical outcomes.

Statement 8: Avoid Arbitrary Criteria for Mucosal Thickening
The surgeon should not plan the extent of sinus surgery (eg, which specific sinuses to operate on) solely based on arbitrary criteria regarding a minimal level of mucosal thickening, sinus opacification, or outflow obstruction on a CT scan.
Evidence strength: Recommendation based on a preponderance of benefit over harm.

Additionally, in August 2025, the AAO-HNS updated their Adult Sinusitis Clinical Practice Guideline, which does not provide guidance related to FESS.

Pediatric CRS

The AAO-HNS Clinical Consensus Statement for Pediatric Rhinosinusitis (Brietzke, 2014) defines its target population as individuals between 6 months and 18 years of age. That guideline defined pediatric CRS as:

At least 90 continuous days of 2 or more symptoms of purulent rhinorrhea, nasal obstruction, facial pressure/pain, or cough and either endoscopic signs of mucosal edema, purulent drainage, or nasal polyposis, and/or CT scan imaging showing mucosal changes within the ostiomeatal complex and/or sinuses^. Pediatric CRS can be subclassified into CRS with or without nasal polyposis. In the Clinical Consensus Statement for pediatric CRS, there was a strong consensus that children who present with polyps represent a distinct patient subgroup compared to children who do not have polyps. Patients with nasal polyposis are thought to constitute a different subtype of CRS with differing pathophysiology and optimal management. Specifically, these children carry an increased risk of underlying conditions such as cystic fibrosis, allergic fungal sinusitis and antrochoanal polyps.

Guideline statement number 4 notes: “Management of the children with nasal polyps and CRS is distinctly different than management of children with CRS unaccompanied by nasal polyps.”

Specifically, children presenting with nasal polyps carry a substantially increased risk of underlying cystic fibrosis and should be specifically assessed for this and other serious comorbid disorders such as allergic fungal sinusitis or antrochoanal polyps (Brietzke, 2014).

Additionally, the following statements were made in this document:

23. Endoscopic sinus surgery (ESS) is an effective procedure for treating pediatric chronic rhinosinusitis (PCRS) that is best performed after medical therapy, adenoidectomy, or both have failed.
25. Image-guided ESS is useful for revision ESS cases and/or for patients with extensive nasal polyposis that can distort anatomical landmarks.

The 2020 European Position Paper on Rhinosinusitis and Nasal Polyps (Fokkens, 2020) notes that medical therapy remains the primary management approach for pediatric CRS. Saline nasal irrigation is recommended as first-line therapy. The addition of topical (intranasal) antibiotics to saline irrigation is not recommended, and there is no supporting evidence for the routine use of oral or intravenous antibiotics. Prolonged macrolide therapy is also not supported by current evidence and is not recommended. Intranasal corticosteroids are recommended despite limited pediatric-specific evidence, based on established safety in children and demonstrated efficacy in adult CRS and pediatric rhinitis populations. There is insufficient evidence to support the routine use of ancillary therapies including antihistamines, leukotriene modifiers, decongestants, or mucolytics unless they are indicated for comorbid conditions (for example, allergic rhinitis or gastroesophageal reflux disease). Surgery is reserved for children with persistent illness despite appropriate medical therapy and in select cases of complicated acute rhinosinusitis or anatomic obstruction. Adenoidectomy, with or without antral irrigation, is considered the preferred initial surgical approach in younger children due to its safety and simplicity. Antral irrigation may provide additional benefit in children with asthma and more severe disease on imaging. The position paper notes that FESS is a safe and potentially effective option, either as primary therapy in older children or following adenoidectomy failure. Reported complication rates for pediatric FESS are low (approximately 0.6% major and 2% minor).

Specific recommendations include:

• Adenoidectomy is effective in younger children with symptoms of CRS. The EPOS steering group supports adenoidectomy in young children refractory to appropriate medical therapy. (Level of evidence 4)
• FESS is safe and effective for the treatment of older children with CRS refractory to medical therapy or previous adenoidectomy. (Level of evidence 4)

Level 4 evidence is often considered lower in the hierarchy of evidence compared to evidence from systematic reviews or RCTs.

In a 2020 AAO-HNS Bulletin, Stapleton discussed the complexity of diagnosing and managing pediatric rhinitis and CRS. There is considerable variability in the presentation, symptomatology, medical management, and surgical treatment for these children. Children under 6 years of age may have a different pathophysiology and presentation than a child older than 12 years. Multiple factors like age, atopy, viral exposure, sinonasal anatomic development, and microbiologic dysbiosis contribute to varying presentations and treatment; therefore a stepwise approach is necessary, starting with medical therapies. When medical management is not sufficient, endoscopic sinus surgery is an option. Research into personalized diagnostics, including sinonasal microbiome analysis, CRS endotyping, and biologic therapies, shows promise for advancing the treatment of pediatric CRS.

FESS is a second-line surgical intervention in a stepwise treatment approach for pediatric CRS. FESS is reserved for refractory cases following failure of first-line surgical management, specifically after prior adenoidectomy has been performed.
Although published evidence addressing FESS is limited, clinical experience over the past decade has demonstrated the clinical benefit of this procedure compared to more invasive techniques.

Postoperative Debridement

There have been several studies addressing the use of nasal or sinus postoperative debridement after FESS surgery. Results have been mixed with regard to the benefit of this procedure. A small study found no significant benefit from debridement (Nilssen, 2002). Another study found only minor symptom improvement when debridement was performed during the first postoperative week (Kemppainen, 2008). Another study found that debridement significantly reduces crusting and postoperative adhesions as compared with saline irrigation, but was associated with significantly more postoperative pain (Bugten, 2006). The authors reported that, at 12 weeks after surgery, there were no significant differences between individuals receiving or not receiving debridement in terms of polyps, edema, crusting, and discharge. A very small, randomized trial suggested that 1-week intervals were optimal for performing debridement (Lee, 2008).

Fishman conducted a prospective, randomized, controlled, single-blinded, within-participant trial involving 24 participants who underwent FESS and were followed for 3 months postoperatively (2011). Each participant had frequent endoscopic cleaning on one side versus minimal intervention on the other in the early postoperative period. The authors reported that there was no overall statistically significant difference between the two groups (p=0.37). A post-hoc subgroup analysis revealed a significant effect of regular suction clearance on adhesions at 3 months (p=0.048). No significant difference was observed in the occurrence of edema, polyps, granulation, discharge or crusting. An RCT reported by Alsaffar (2013) involved 58 participants randomized to receive either two postoperative debridements at 2 and 4 weeks (n=28) or no debridement (n=30). The authors reported that there was no difference between the groups at 4 weeks in regard to Lund-Kennedy Endoscopic Score (p=0.59) or sino-nasal outcome test (SNOT)-21 scores (p=0.47). Similar results were reported at 6 months for Lund-Kennedy Endoscopic Score (p=0.46) and SNOT-21 (p=0.71). Although both groups reported low overall levels of pain in the early postoperative time period based on visual analog scale measurements, the debridement group had significantly higher overall pain score vs. controls (p=0.019). Finally, the authors investigated the difference in inconvenience between the two groups using the Post Operative Inconvenience Scale (POIS). A significant difference between groups was reported, with the debridement group significantly more inconvenienced than the control group (p=0.002).

In 2016, Varsak published the results of an RCT involving 62 participants with CRS who underwent FESS. Participants were assigned to undergo post-operative debridement once at post-op week 1 or at post-op weeks 1, 2 and 4. Assessments were taken with a visual analog scale for 9 main symptoms of discomfort within the first 4 weeks, with the Lund-Kennedy endoscopic score at weeks 4 and 24, and with the SNOT-20 at week 24. Visual analog scores in the single debridement group showed significantly less discomfort at post-op week 4 (p=0.004) and less negative effects on their work (p=0.013). No statistically significant differences were reported between the 2 groups in the week 4 and week 24 Lund-Kennedy endoscopic score or in the week 24 SNOT-20 scores (p>0.05). The authors concluded that frequent debridement causes more discomfort, more facial pain, and more negative effects on participants' work, and that it was not superior to a single debridement on post-FESS day 7.

Shi (2015) described the results of an RCT involving 67 participants with CRS randomized to receive either 3 post-op debridements at 1, 4, and 8 weeks (low frequency) or weekly debridements for 8 weeks post-op (high frequency). At 4 weeks, complaints of facial pain rated on a 10-point visual analog scale were significantly less severe in the low frequency group compared to the high frequency group (2.74 vs. 5.92, p<0.01). There were significantly fewer severe nasal blockages noted in the high frequency group (3.45 vs. 4.83, p<0.05). Based on endoscopic findings and Lund-Kennedy Endoscopic Score at 4 weeks, there were no significant between-group differences regarding the presence of polyps, edema or discharge. However, a significantly lower incidence of severe crusts was noted in the high frequency group (1.12 vs. 1.90, p=0.003), but less scarring in the low frequency group (1.11 vs. 0.83 ± 0.78, p<0.01). At 8 weeks, no significant differences were noted between groups on all domains of the visual analog scale and Lund-Kennedy Endoscopic Score, except less scarring in the high frequency group (0.47 vs. 0.67, p<0.01). They concluded that the benefit of frequent debridement during the early post-op period was not in positive correlation with participants recovering from ESS and that excessive debridement may induce more surgical trauma and cause more facial pain to individuals.

As noted above, the AAO-HNS published a consensus statement regarding PCRS (Brietzke, 2014). The following statement addressing debridement was made in this document:

27. Postoperative debridement after ESS for PCRS is not essential for treatment success.

Postoperative debridement may need to occur for longer periods in some individuals with conditions that may lead to the development of complications. Such individuals include those with severe resistant nasal polyposis, neoplasm, or allergic fungal sinusitis. However, even in these individuals, debridement should be prompted by symptoms which arise as a consequence of the more extensive surgery or underlying disease. There is no evidence that debridement in the absence of symptoms is associated with improved outcomes even when there are risk factors for complications after FESS.

In 2018 the Cochrane library released a review addressing debridement versus no debridement for the postoperative care of individuals undergoing endoscopic sinus surgery (Tzelnick, 2018). The conclusions of this report were:

We are uncertain about the effects of postoperative sinonasal debridement due to high risk of bias in the included studies and the low quality of the evidence. Sinonasal debridement may make little or no difference to disease-specific health-related quality of life or disease severity. Low-quality evidence suggests that postoperative debridement is associated with a significantly lower risk of adhesions at three months follow-up. Whether this has any impact on longer-term outcomes is unknown.

Acute rhinosinusitis (ARS): Up to 4 weeks of discolored nasal drainage accompanied by nasal obstruction, facial pain, pressure, or fullness. Nasal obstruction may be reported by the patient as nasal obstruction, congestion, blockage, or stuffiness, or may be diagnosed by physical examination. Facial pain, pressure, or fullness may involve the anterior face, periorbital region, or manifest with headache that is localized or diffuse.

Chronic rhinosinusitis (CRS): Twelve weeks or longer of two or more of the following symptoms or signs:

• Thick and/or discolored drainage
• Nasal obstruction (congestion)
• Facial pain, pressure, or fullness
• Decreased sense of smell and inflammation as documented by one or more of the following findings:
  • abnormal mucus or edema in the middle meatus
  • radiologic imaging showing inflammation of the paranasal sinuses

Complicated rhinosinusitis: Extra paranasal sinus extension, defined as extensions of disease beyond the confines of the sinuses, for example, orbital or intracranial spread.

Pediatric Chronic Rhinosinusitis: Inflammation of the nose and paranasal sinuses lasting greater than or equal to 12 weeks characterized by two of the following symptoms:

• Nasal obstruction/congestion
• Nasal discharge (anterior/posterior nasal drip)
• Chronic cough
• Facial pain/pressure and 1 objective sign of sinonasal inflammation:
  • Nasal endoscopy findings (for example, mucosal edema, purulent drainage, nasal polyps)
  • Imaging abnormalities on sinus CT consistent with mucosal disease

Recurrent acute rhinosinusitis: Four or more episodes per year of acute bacterial rhinosinusitis (ABRS) without signs or symptoms of rhinosinusitis between episodes.

SNOT scores: The (sinonasal outcome test) SNOT-20 score is a validated, disease-specific quality-of-life measure for rhinosinusitis containing 20 items assessing nasal, sinus, and general symptoms, with scores ranging from 0-5 per item. The SNOT-22 is a modification of the SNOT-20 that adds two items (nasal blockage and sense of smell/taste) to improve comprehensiveness. Both instruments demonstrate excellent psychometric properties. The SNOT-20 shows Cronbach's alpha of 0.9 and test-retest reliability of r = 0.9, successfully discriminating between disease severity levels and detecting clinical change. The SNOT-22 demonstrates similarly robust properties with Cronbach's alpha of 0.91 and test-retest reliability of 0.93, effectively discriminating between individuals with chronic rhinosinusitis and healthy controls (p<0.0001). Factor analyses have identified 4-5 distinct domains including nasal, sleep, ear/facial, and emotional symptoms. The SNOT-22 has an established minimal clinically important difference (MCID) of 8.9 points for surgical patients, representing the smallest change detectable by patients. For medically managed individuals, the MCID is approximately 12 points, with distribution-based methods also supporting an MCID of 8.0 points. The SNOT-20 itself lacks widely established MCID values in the literature, which contributed to the development and adoption of the SNOT-22 as the preferred instrument in contemporary rhinology practice.

Peer Reviewed Publications:

1. Alanin MC, Hopkins, C. Effect of functional endoscopic sinus surgery on outcomes in chronic rhinosinusitis. Curr Allergy Asthma Rep. 2020; 20(7):27.
2. Alsaffar H, Sowerby L, Rotenberg BW. Postoperative nasal debridement after endoscopic sinus surgery: a randomized controlled trial. Ann Otol Rhinol Laryngol. 2013; 122(10):642-647.
3. Benninger MS, Ferguson BJ, Hadley JA, et al. Adult chronic rhinosinusitis: definitions, diagnosis, epidemiology, and pathophysiology. Otolaryngol Head Neck Surg. 2003; 129(3 Suppl):S1-S32.
4. Bitner BF, Prasad KR, Goshtasbi K, et al. Outcomes of concurrent functional endoscopic sinus surgery and rhinoplasty: a meta-analysis. AM J Rhinol Allergy. 2021; 35(5):587-595.
5. Blomqvist EH, Lundblad L, Anggard A, et al. A randomized controlled study evaluating medical treatment versus surgical treatment in addition to medical treatment of nasal polyposis. J Allergy Clin Immunol. 2001; 107(2):224-228.
6. Bugten V, Norgard S, Steinsvag S. The effects of debridement after endoscopic sinus surgery. Laryngoscope. 2006; 116(11):2037-2043.
7. Ehnhage A, Olsson P, Kölbeck KG, et al. Functional endoscopic sinus surgery improved asthma symptoms as well as PEFR and olfaction in patients with nasal polyposis. Allergy. 2009; 64(5):762-769.
8. Fishman JM, Sood S, Chaudhari M, et al. Prospective, randomised controlled trial comparing intense endoscopic cleaning versus minimal intervention in the early post-operative period following functional endoscopic sinus surgery. J Laryngol Otol. 2011; 125(6):585-589.
9. Gill AS, Alt JA, Detwiller KY, et al. Management paradigms for chronic rhinosinusitis in individuals with asthma: an evidence-based review with recommendations. Int Forum Allergy Rhinol. 2023; 13(9):1758-1782.
10. Hamilos DL. Chronic sinusitis. J Allergy Clin Immunol. 2000; 106(2):213-227.
11. Kemppainen T, Seppä J, Tuomilehto H, et al. Repeated early debridement does not provide significant symptomatic benefit after ESS. Rhinology. 2008; 46(3):238-242.
12. Lee JY, Byun JY. Relationship between the frequency of postoperative debridement and patient discomfort, healing period, surgical outcomes, and compliance after endoscopic sinus surgery. Laryngoscope. 2008; 118(10):1868-1872.
13. Manning S. Surgical intervention for sinusitis in children. Curr Allergy Asthma Rep. 2001; 1(3):289-296.
14. Nilssen E, Wardrop P, El-Hakim H, et al. A randomized control trial of post-operative care following endoscopic sinus surgery: debridement versus no debridement. J Laryngol Otol. 2002; 116(2):108-111.
15. Penttila MA, Rautiainen ME, Pukander JS, Karma PH. Endoscopic versus Caldwell-Luc approach in chronic maxillary sinusitis: comparison of symptoms at one-year follow-up. Rhinology. 1994; 32(4):161-165.
16. Penttila MA, Rautiainen ME, Pukander JS, Kataja M. Functional vs. radical maxillary surgery. Failures after functional endoscopic sinus surgery. Acta Otolaryngol Suppl. 1997; 529:173-176.
17. Ragab SM, Lund VJ, Scadding G. Evaluation of the medical and surgical treatment of chronic rhinosinusitis: a prospective, randomised, controlled trial. Laryngoscope. 2004; 114(5):923-930.
18. Rahman T, Alam MM, Ahmed S, et al. Outcome of endoscopic sinus surgery in the treatment of chronic rhinosinusitis. Mymensingh Med J. 2016; 25(2):261-270.
19. Shi L, Feng Y, Cui W, et al. Effect evaluation of repeated debridement after endoscopic sinus surgery. Int J Clin Exp Med. 2015; 8(1):928-933.
20. Smith TL, Kern R, Palmer JN, et al. Medical therapy vs surgery for chronic rhinosinusitis: a prospective, multi-institutional study with 1-year follow-up. Int Forum Allergy Rhinol, 2013; 3(1):4-9.
21. Varsak YK, Yuca K, Eryilmaz MA, Arbag H. Single seventh day debridement compared to frequent debridement after endoscopic sinus surgery: a randomized controlled trial. Eur Arch Otorhinolaryngol. 2016; 273(3):689-695.

Government Agency, Medical Society, and Other Authoritative Publications:

1. American Academy of Otolaryngology-Head and Neck Surgery. Clinical Indicators: Endoscopic Sinus Surgery, Adult. Updated January 2015. Available at: https://www.entnet.org/resource/clinical-indicators-endoscopic-sinus-surgery-adult/. Accessed on March 16, 2026.
2. American Academy of Otolaryngology-Head and Neck Surgery. Clinical Indicators: Endoscopic Sinus Surgery, Pediatric. August 7, 2014. Available at: https://www.entnet.org/resource/clinical-indicators-endoscopic-sinus-surgery-pediatric/. Accessed on March 16, 2026.
3. American Academy of Otolaryngology-Head and Neck Surgery. Clinical Practice Guideline: Management of Chronic Rhinosinusitis. May 27, 2025. Available at: CPG: Surgical Management of Chronic Rhinosinusitis - American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS). Accessed on March 16, 2026.
4. American Academy of Otolaryngology-Head and Neck Surgery. Pediatric Rhinitis and Chronic Rhinosinusitis. February 15, 2024. Available at: https://bulletin.entnet.org/clinical-patient-care/article/22886531/pediatric-rhinitis-and-chronic-rhinosinusitis#:~:text=Pediatric%20rhinitis%20and%20chronic%20rhinosinusitis%20(CRS)%20are%20challenging%20diagnoses%20to,the%20age%20of%20the%20patient. Accessed March 16, 2026.
5. Brietzke SE, Shin JJ, Choi S, et al. Clinical consensus statement: pediatric chronic rhinosinusitis. Otolaryngol Head Neck Surg. 2014; 151(4):542-553.
6. Fokkens WJ, Lund VJ, Hopkins C, et al. European Position Paper on Rhinosinusitis and Nasal Polyps 2020. 2020(Suppl 29):1-464.
7. Khalil HS, Nunez DA. Functional endoscopic sinus surgery for chronic rhinosinusitis. Cochrane Database Syst Rev. 2006;(3):CD004458.
8. Khan AH, Reaney M, Guillemin I, et al. Development of Sinonasal Outcome Test (SNOT-22) domains in chronic rhinosinusitis with nasal polyps. Laryngoscope. 2022; 132(5):933-941.
9. Payne SC, McKenna M, Buckley J, et al. Clinical Practice Guideline: Adult Sinusitis Update. Otolaryngology-Head and Neck Surgery. 2025; 173(Suppl 1):S1-S56.
10. Peters AT, Spector S, Hsu J, et al.; Joint Task Force on Practice Parameters, representing the American Academy of Allergy, Asthma and Immunology, the American College of Allergy, Asthma and Immunology, and the Joint Council of Allergy, Asthma and Immunology. Diagnosis and management of rhinosinusitis: a practice parameter update. Ann Allergy Asthma Immunol. 2014; 113(4):347-85.
11. Rosenfeld RM, Piccirillo JF, Chandrasekhar SS, et al. Clinical practice guideline (update): adult sinusitis. Otolaryngol Head Neck Surg. 2015; 152(2 Suppl):S1-S39.
12. Tzelnick S, Alkan U, Leshno M, et al. Sinonasal debridement versus no debridement for the postoperative care of patients undergoing endoscopic sinus surgery. Cochrane Database Syst Rev. 2018;(11):CD011988.

1. National Library of Medicine. Medical Encyclopedia. Sinusitis. Review Date May 2, 2024. Available at: http://www.nlm.nih.gov/medlineplus/ency/article/000647.htm. Accessed on April 24, 2026.

Acute rhinosinusitis (ARS)
Chronic rhinosinusitis (CRS)
Complicated rhinosinusitis
FESS
Functional Endoscopic Sinus Surgery
Mucocele
Nasal Polyposis
Pediatric Chronic Rhinosinusitis
Recurrent acute rhinosinusitis
Sinusitis
SNOT scores

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