Surgical management of chronic rhinosinusitis: a narrative review

Article information

J Korean Med Assoc. 2025;68(7):417-426

Publication date (electronic) : 2025 July 10

doi : https://doi.org/10.5124/jkma.25.0066

Yung Jin Jeon, MD, PhD^,1,2

¹Department of Otorhinolaryngology, Gyeongsang National University Hospital, Jinju, Korea

²Institute of Health Sciences, Gyeongsang National University, Jinju, Korea

Corresponding author: Yung Jin Jeon E-mail: myjin8704@gnu.ac.kr

Received 2025 April 29; Accepted 2025 June 25.

Abstract

Introduction

Pathophysiology of CRS and the Role of Surgical Treatment

Historically, CRS was viewed primarily as an infectious disease, with antibiotic therapy as the mainstay of treatment and a focus on eradicating pathogenic organisms. Oral antibiotics were commonly prescribed, but surgical intervention was considered when symptoms persisted or worsened despite medical therapy. It has been reported that up to 50% of patients with CRS eventually require surgical treatment [6].

Traditional surgical approaches were aimed at relieving obstruction of the ostiomeatal unit (OMU) to restore adequate drainage and ventilation. This strategy was based on the concept that impaired mucociliary clearance in the sinus mucosa leads to localized hypoxia within obstructed sinuses, resulting in epithelial barrier dysfunction and diminished defenses against microbial infection.

Although surgical treatment of CRS has shown higher efficacy than medical management, recurrence remains a substantial concern. In patients with CRS and nasal polyps, recurrence rates range from 60% to 80%, and approximately 14% to 24% may require revision surgery due to severe disease progression [7]. These findings highlight the limitations of attributing CRS solely to anatomical obstruction, emphasizing the role of heterogeneous immunological and inflammatory mechanisms. Even when surgery successfully removes polyps and restores sinus ventilation and mucociliary function, completely suppressing the underlying immunological inflammation remains challenging.

CRS was previously classified phenotypically according to the presence or absence of nasal polyps. However, the European Position Paper on Rhinosinusitis and Nasal Polyps (EPOS) 2020 introduced an endotype-based classification, distinguishing primary from secondary CRS and further subcategorizing primary CRS based on clinical markers linked to allergy and type 2 inflammation [1,8]. Thus, surgical decision-making for CRS is no longer determined solely by the presence of nasal polyps. In contrast, the American International Consensus Statement on Allergy and Rhinology: Rhinosinusitis 2021 continues to frame treatment strategies based on the presence of nasal polyps [9].

CRS is now increasingly understood as a chronic inflammatory disorder driven by an aberrant immune response to environmental factors, rather than simply as an obstructive or infectious disease. Accordingly, the objectives of surgery have evolved. Rather than focusing exclusively on restoring sinus patency or ventilation, the primary goal of surgical treatment in CRS is to alleviate symptoms and improve quality of life, except in cases involving severe complications of the orbit or central nervous system, where surgery is indicated regardless of symptom severity. As a chronic disease that requires ongoing, multidisciplinary management, ESS is one component of comprehensive care that not only restores ventilation and drainage but also optimizes the delivery of topical therapies and saline irrigations [5,9].

Indications and Timing of Surgical Treatment for CRS

Traditionally, surgical intervention for CRS has been considered when maximal medical therapy fails [9]. However, universally established criteria are lacking due to variability in treatment modalities, duration, and patient adherence. Actual rates of ESS vary considerably by region: in 2015, the average number of surgeries per 1,000 population was 0.94 in the United States (US), 0.53 in the United Kingdom (UK), 0.33 in Alberta (Canada), and 0.71 in Finland [10–12]. A meta-analysis reported that only 21% of CRS patients undergoing ESS had received adequate preoperative medical therapy. Among these patients, 91% had used intranasal corticosteroid sprays for a mean of eight weeks, 61% had used oral steroids for a mean of 18 days, and 89% had received oral antibiotics for a mean of 23 days [13]. This highlights the need for clearer and more standardized surgical indications. Recent studies have responded by proposing objective preoperative assessments, such as the Sino-Nasal Outcome Test-22 (SNOT-22) and the Lund-Mackay computed tomography (CT) score [14].

A key criterion for evaluating the success of ESS is achieving the minimally clinically significant difference (MCID) in SNOT-22 scores. Studies indicate that 70% to 80% of CRS patients attain the MCID after ESS [15]. Patients with preoperative SNOT-22 scores above 30 are highly likely to reach the MCID threshold, while those with scores below 20 are less likely, likely due to a floor effect. It is generally recommended that surgery be considered if, after at least eight weeks of intranasal corticosteroid spray and, as needed, a course of oral steroids or antibiotics, the SNOT-22 score remains above 20. Rudmik et al. [16] provided evidence-based indications, recommending that CRS patients with nasal polyps, a Lund-Mackay score ≥1, and a persistent SNOT-22 score above 20 despite appropriate medical therapy may be considered for surgery. Although these thresholds are not absolute, they offer useful guidance for clinical decision-making and can help reduce unnecessary surgical interventions.

Recent research has also highlighted the importance of surgical timing. Prolonged intervals between diagnosis and surgery may negatively affect prognosis [17]. For example, Hopkins et al. [18] found that patients undergoing ESS within 12 months of diagnosis achieved better long-term symptom control. Additionally, analyses from the UK and US indicate that early ESS is associated with a reduced risk of subsequent asthma development [19]. A Swedish study further demonstrated that patients with CRS duration under 12 months experienced the most significant improvements in SNOT-22 scores after ESS [20]. Conversely, a US multicenter cohort study suggested that longer disease duration may be associated with greater postoperative quality-of-life gains [21]. However, extended disease duration may also lead to irreversible mucosal changes, emphasizing the need for timely surgical intervention. While randomized controlled trials are lacking, observational studies suggest that delayed surgery may compromise quality-of-life improvements and increase the risk of comorbidities such as asthma.

In summary, surgical management of CRS should integrate SNOT-22 scores, symptom control, and disease course. In patients with specific severe symptoms—such as anosmia, significant nasal obstruction, or recurrent infections—clinically meaningful improvement may be achieved with ESS even when total SNOT-22 scores are not markedly elevated. When symptoms persist despite optimized medical therapy, timely consideration of surgery is recommended to avoid unnecessary delays. Preoperative CT imaging is essential for surgical planning, with the Lund-Mackay score providing an objective measure of disease extent [1,9]. Future research should focus on establishing more standardized surgical indications.

Preoperative CT

Preoperative CT is indispensable for the diagnosis and surgical planning of CRS. Although neither EPOS nor other guidelines specify the timing of CT imaging, the American College of Radiology recommends non-contrast sinus CT as the imaging modality of choice for CRS diagnosis [22]. In cases where CRS is confirmed by nasal endoscopy and no significant findings—such as mucoceles—are present, CT imaging can be deferred until surgery is considered. However, preoperative CT is critical for delineating disease extent and assessing anatomical structures that may increase intraoperative complication risks. Multiplanar imaging (axial, coronal, and sagittal views) is necessary for comprehensive anatomical assessment [23]. Several systematic evaluation methods have been introduced, with the CLOSE technique (cribriform plate, lamina papyracea, Onodi cell, sphenoid sinus, and ethmoidal arteries) being widely used (Table 1) [1,24]. This approach improves the preoperative identification of high-risk anatomical variants and enhances intraoperative safety. Repeat CT imaging after initial preoperative assessment is generally unnecessary unless additional surgical interventions are planned. In a retrospective study analyzing 56 patients with an average CT interval of 782 days between scans, no significant changes in Lund-Mackay scores were observed, and repeat imaging did not influence surgical decision-making [25].

Table 1.

Preoperative paranasal sinus computed tomography checklist

Anesthesia Techniques for ESS

Innovations in anesthesia techniques have paralleled advances in ESS. The choice of anesthesia has a direct impact on intraoperative bleeding, visualization, operative time, and complication risk. The two main anesthetic methods for ESS are total intravenous anesthesia (TIVA) and inhalational anesthesia (IA), both of which may include controlled hypotension to minimize bleeding. TIVA uses agents such as propofol, often with adjuncts like remifentanil or fentanyl, while IA involves halogenated ethers such as isoflurane, sevoflurane, or desflurane. Studies have shown that TIVA reduces central nervous system-mediated peripheral blood pressure, thereby reducing venous bleeding. In contrast, IA induces hypotension through peripheral vasodilation but may paradoxically increase capillary bleeding [26]. TIVA is also associated with lower rates of postoperative nausea and vomiting compared to IA, and may be more cost-effective. Controlled hypotension, in which the mean arterial pressure (MAP) is intentionally lowered, is crucial for improving the surgical field and reducing bleeding [27]. However, MAP below 60 mmHg increases the risk of cerebral ischemia; thus, maintaining MAP between 60 to 70 mmHg is generally considered safe. Combining TIVA with dexmedetomidine (an α2-agonist) or a beta-blocker has been proposed as an effective strategy to optimize surgical conditions.

Advances in ESS

The paranasal sinuses include the maxillary, anterior ethmoid, posterior ethmoid, sphenoid, and frontal sinuses. Prior to the advent of endoscopic techniques, traditional surgical approaches such as Caldwell-Luc procedures and intranasal ethmoidectomy required extensive removal of diseased sinus mucosa. However, subsequent discoveries that mucociliary clearance occurs through the natural sinus ostia, and that the sinus mucosa is capable of regeneration even after injury, led to a paradigm shift toward more conservative, function-preserving techniques [28]. As a result, middle meatal antrostomy (MMA), which enlarges the natural maxillary ostium, has largely replaced inferior meatal antrostomy in maxillary sinus surgery.

The introduction of endoscopic methods enabled direct visualization of the sinus mucosa and the development of functional ESS, which emphasizes the selective removal of only irreversibly diseased tissue. Functional ESS is designed to clear transitional areas, particularly the anterior ethmoid region, to restore sinus ventilation and drainage without the need for extensive resection. Studies comparing traditional Caldwell-Luc procedures with MMA have shown the superiority of MMA in terms of symptom improvement and mucosal preservation [29].

In recent years, image-guided navigation systems that integrate preoperative CT data for real-time intraoperative localization have further enhanced the safety and precision of ESS [30]. In Korea, partial insurance reimbursement is provided for this technology under specific indications. The American Academy of Otolaryngology-Head and Neck Surgery recommends the use of image guidance for revision surgery, in cases of distorted anatomy, or when critical anatomical landmarks are difficult to identify (Table 2) [31].

Table 2.

Comparison of Korea National Insurance Criteria and AAO-HNS indications for navigation-assisted sinus surgery

Extent of ESS

The location and severity of pathology determine the necessary extent of surgery. There is ongoing debate as to whether all sinuses should be surgically opened or only those with clear pathological involvement. Recent advances include minimally invasive sinus techniques (MIST) and balloon sinuplasty [32,33]. MIST seeks to preserve the natural ostium and targets only transitional spaces, thereby maximizing mucosal preservation. For example, MIST removes the uncinate process without directly enlarging the maxillary ostium. Balloon sinuplasty, performed under endoscopic guidance, involves the insertion and inflation of a balloon catheter at the site of obstruction, thereby expanding the sinus ostium while preserving the mucosa. This technique minimizes bleeding, tissue trauma, and postoperative scarring. MIST and balloon sinuplasty are suitable for patients with mild CRS, whereas more extensive ESS may be required for severe CRS or CRS with nasal polyps.

A significant point of debate in ESS is whether to preserve or remove inflamed sinus mucosa. Nasalization procedures, which involve the extensive removal of inflamed mucosa, have shown efficacy in reducing symptoms and polyp recurrence in CRS with nasal polyps [34]. More aggressive approaches, such as the “reboot” procedure, involving complete or partial removal of the sinus mucosa, or endoscopic medial maxillectomy, have also been proposed for refractory disease [35]. However, mucosal resection carries risks including olfactory impairment, cerebrospinal fluid leak, and chronic crusting, necessitating careful patient selection. While current evidence supports the benefits of these approaches in CRS with nasal polyps, direct comparative studies with mucosa-preserving ESS remain limited, underscoring the need for further research.

Anatomically, the maxillary sinus is the second most commonly treated site after the anterior ethmoid sinus, in keeping with traditional principles of improving OMU function. Multiple studies in CRS with nasal polyps have highlighted the importance of maintaining the patency of the natural maxillary ostium. In ethmoid sinus surgery, precise removal based on anterior or posterior compartment involvement is critical, given the proximity of vital structures such as the optic nerve and orbit. Surgical planning for posterior ethmoid sinuses must also account for their continuity with the sphenoid and frontal sinuses. Sphenoid sinus surgery, indicated for obstructive lesions such as polyps or fungal balls, demands a high degree of precision due to the close relationship with the optic nerve and internal carotid artery; excessive enlargement may result in dural exposure or optic nerve injury. Surgical approaches include transnasal direct and transethmoidal routes, both requiring a thorough understanding of sinus anatomy.

Frontal sinus surgery remains the most technically challenging aspect of ESS due to the narrow anatomy and high risk of complications with aggressive manipulation. Draf’s classification [36], introduced in 1991, continues to be widely used: Draf I removes only anterior ethmoid cells without manipulating the frontal ostium; Draf IIa extends from the lamina papyracea to the middle turbinate, typically creating an ostial diameter ≥4.5 mm [37]; Draf IIb removes the frontal sinus floor up to the nasal septum and is indicated for cases with lateralized middle turbinate, adhesions from prior surgery, mucoceles, or tumors [38]; Draf III, also known as the endoscopic modified Lothrop procedure, involves removing the upper nasal septum and bilateral frontal sinus floors to create a common drainage pathway extending from one lamina papyracea to the other.

Complications of ESS

Despite significant technological advancements and the refinement of surgical techniques, complications remain possible during ESS due to the close proximity of the paranasal sinuses to critical structures such as the skull base, orbit, and major vessels. Complications are classified by frequency and severity into three grades: minor (grade I), moderate (grade II), and major (grade III) (Table 3) [1,9]. Thorough preoperative CT imaging is essential for identifying anatomical variations. Intraoperative awareness of key structures, along with selective use of image-guided navigation systems, can substantially reduce complication rates. Effective blood pressure management and optimal patient positioning during surgery also contribute to improved safety outcomes.

Table 3.

Complications of endoscopic sinus surgery

Role of Septoplasty and Turbinate Surgery in ESS

Anatomical factors, such as septal deviation or turbinate hypertrophy, can impede endoscopic access and visualization during ESS. In these situations, concomitant septoplasty or turbinate surgery is often considered to optimize surgical effectiveness. Septoplasty enhances surgical exposure, while inferior turbinate reduction improves postoperative nasal airflow and symptom relief. Middle turbinate resection may be performed if the structure obstructs access or is damaged during surgery. Some studies indicate that middle turbinate resection may improve surgical access, disease clearance, and reduce recurrence rates [39]. However, the middle turbinate is a key landmark for intranasal spatial orientation and mucociliary function. Excessive resection can result in long-term sequelae such as empty nose syndrome. Therefore, decisions regarding middle turbinate resection should be individualized based on anatomical features, disease extent, and prior interventions. A conservative approach is generally recommended, with limited resection undertaken only when specifically indicated.

Postoperative Care Following ESS

Appropriate postoperative care is crucial for promoting mucosal healing, minimizing complications, and optimizing surgical outcomes. The most strongly recommended interventions include nasal saline irrigation and intranasal corticosteroid sprays. Saline irrigation efficiently removes mucus, crusts, and inflammatory mediators with minimal adverse effects. Isotonic saline is generally preferred over hypertonic solutions due to similar efficacy and reduced irritation. Irrigation should commence within 24 to 48 hours postoperatively, with high-volume (>1,000 mL), twice-daily irrigations providing the greatest benefit during the initial two weeks [40]. Intranasal corticosteroid sprays have demonstrated clinically significant improvements in SNOT-22 scores and endoscopic findings [41]. Routine use of systemic corticosteroids is not supported for long-term postoperative management, given the potential for adverse effects and lack of sustained benefit.

Routine postoperative oral antibiotics are not recommended; their use should be individualized. Some studies report statistically significant symptomatic improvement with long-term, low-dose macrolides [42,43], but meta-analyses have not demonstrated meaningful long-term benefits in reducing infection, alleviating symptoms, or preventing toxic shock syndrome [44,45]. Postoperative debridement can facilitate re-epithelialization and decrease adhesion formation by removing residual crusts and secretions. However, selective, rather than routine, debridement is advised due to patient discomfort [46]. Other topical agents, such as hyaluronic acid and mitomycin C, have been studied, but current evidence does not support their routine use.

Revision Surgery for CRS

Revision ESS is indicated for patients with persistent or recurrent symptoms following initial surgery. Surgical objectives are individualized and may range from simple adhesion or scar removal and correction of lateralized turbinates to more extensive procedures such as Draf III frontal sinus surgery, medial maxillectomy, or removal of the anterior sphenoid wall. The primary aims are symptom relief, reduction in medication dependence, and quality-of-life improvement, with patient-reported outcome measures, such as the SNOT-22, used for assessment [47]. Revision surgery also seeks to create cavities suitable for topical therapy, address anatomical variants, and remove residual cells and scar tissue. Revision is generally considered after at least two months of optimal medical management, including antibiotics, topical and systemic steroids, and saline irrigation, when symptoms persist or imaging reveals mucosal thickening, purulence, polyps, or edema. In CRS with nasal polyps, recurrence is the main indication for revision. In CRS without nasal polyps, the need for surgery is less clear and should be guided by objective findings such as obstruction or localized inflammation. Frontal sinusotomy is among the most technically challenging revision procedures, often necessitated by residual frontal cells, neo-osteogenesis, lateralized middle turbinate, or persistent anterior ethmoid cells [48]. A comprehensive, patient-specific surgical plan based on endoscopic and radiologic evaluation is essential.

Recent Advances in CRS Treatment

Although CRS presents in diverse forms, it can generally be controlled or cured with appropriate medical or surgical therapy. However, some patients remain symptomatic despite comprehensive treatment, including surgery. EPOS defines uncontrolled or refractory CRS as persistent symptoms despite appropriate surgery, intranasal corticosteroid therapy, and no more than two short courses of antibiotics or systemic corticosteroids in the preceding year. CRS with nasal polyps, particularly those of the eosinophilic, type 2 immune response phenotype, is closely associated with asthma and aspirin-exacerbated respiratory disease and is known for its high recurrence rate. More than 50% of recurrent CRS cases are associated with type 2 inflammation, with peripheral eosinophilia serving as a strong predictor of recurrence. Type 2 inflammatory CRS often exhibits resistance to conventional therapy, and repeated systemic steroid use raises the risk of adverse effects, underscoring the need for more effective and safer therapeutic strategies. In this context, biologic agents have emerged as promising adjunctive therapies. Agents targeting key cytokines, such as interleukin (IL)-4, IL-5, and IL-13 (e.g., dupilumab, mepolizumab, omalizumab), have shown significant benefits in patients with CRS with nasal polyps. These biologics are increasingly used as stand-alone therapies or in combination with surgery, offering new treatment options for refractory CRS that does not respond to conventional management.

Conclusion

CRS is a multifactorial disease characterized by complex pathophysiological and immunological mechanisms, necessitating individualized treatment strategies tailored to each patient's phenotype and endotype. When medical therapy is insufficient, ESS is effective for correcting anatomical abnormalities and creating an environment conducive to inflammation control. Optimal outcomes require meticulous surgical planning based on thorough endoscopic and radiologic assessment. Recent advances, including biologic therapies, improved postoperative management strategies, and structured long-term follow-up protocols, have advanced CRS management toward a more integrated, multidisciplinary, and evidence-based approach.

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