7 Medical Management of Maxillary Sinusitis in the Postsurgical Sinus

The diagnostic criteria for CRS in the postsurgical patient are the same as for all patients with CRS as defined by the report of the rhinosinusitis task force.1 There is likely no single pathophysiologic mechanism of CRS in all patients. Biofilms, fungi, superantigens, eosinophil-driven immune processes, and mucociliary dysfunction all represent a diverse group of processes that may lead to the manifestations of CRS. As with any disease process, a careful history must be elicited with special attention to the type and extent of prior surgery and whether that surgery addressed the underlying problem. Patients with persistent or recurrent disease can present a challenge to the rhinologist, and the astute clinician should reassess the original diagnosis and possibly examine preoperative imaging and operative notes. This is especially true for patients who originally present with some of the more nonspecific symptoms of CRS such as sinonasal pain or headache. It is also important to reassess the patient for factors that may modify their management such as asthma, allergic rhinitis, cystic fibrosis, host immunosuppression, and anatomic variations.²

Endoscopic sinus surgery has become one successful facet in the overall management of CRS refractory to medical therapy with success rates estimated between 80 to 95%.^3,4 Surgery allows improvement in mucociliary clearance and sinus ventilation by unobstructing and enlarging the natural maxillary ostium. Surgical failure and recurrent disease continue to be a problem, however, with an estimated 2 to 18% of patients undergoing additional revision surgical procedures.⁵ Surgical failure may be the result of suboptimal prior surgery or iatrogenic disturbance of mucociliary flow. Several retrospective studies have identified the most common causes of surgical failure to be adhesions, residual air cells, and stenosis or obstruction of the natural maxillary ostium.^5,6 A patient’s symptom history may not always be specific for CRS isolated to the maxillary sinus, but the type of prior surgery may provide clues to whether there is residual focal disease in the postsurgical maxillary sinus. For instance, a post-Caldwell-Luc sinus in which all mucosa was stripped is at increased risk for long-term complications from dysfunctional mucociliary clearance and loculated pockets due to scarring within the maxillary sinus itself.⁷ A thorough history should help guide the clinician to the underlying pathology and the correct treatment course.

Endoscopic Evaluation

Diagnostic nasal endoscopy in the clinic is always an important part of the complete physical exam of the postoperative patient. It is especially vital in the immediate postoperative period when endoscopy allows the debridement of nasal crusting and the lysis of adhesions to help prevent late inflammatory complications that might contribute to obstructing the maxillary ostium. Diagnostic endoscopy is usually performed in the decongested state with both straight and angled (45 degree or 70 degree) rigid telescopes and/or flexible endoscopes to assess the maxillary sinus in its entirety. Endoscopy affords the opportunity to assess the patency of the maxillary sinus and search for inflammatory signs associated with the patient’s symptoms. For instance, the middle meatus is examined for purulence, granulation tissue, synechiae, retained uncinate process, or nasal polyps. It is important to document any stenosis of the maxillary antrostomy and the presence of any accessory ostia. The sinonasal mucosa is also evaluated for edema or polypoid changes. The middle turbinate, if not previously amputated, is evaluated to make certain there is no lateralization with obstruction of the middle meatus. The inferior and lateral limits of the maxillary sinus should also be examined to evaluate for dental pathology or loculated pockets that could be contributing to persistent infections. Given the increase in antibiotic-resistant organisms contributing to sinusitis, mucopurulent secretions apparent on endoscopy should be cultured to direct antibiotic therapy. A recent meta-analysis concluded that culture via the middle meatus had a high concordance rate (82%) with the traditional gold standard of maxillary antral puncture cultures.8

Radiographic Evaluation

Noncontrast computed tomography (CT) often proves useful as an additional source of information to supplement a thorough history and physical examination. High-resolution CT scans in coronal as well as sagittal and axial planes excel at evaluating bone detail and anatomy of the paranasal sinuses that may only be partially evident on endoscopic exam.⁹ Particular attention should be given to the area of the natural maxillary ostium to assess its patency and to evaluate for anatomic clues that may be contributing to persistent disease (e.g., a residual uncinate process obstructing the infundibulum, accessory ostia that may contribute to mucus recirculation).

At times a subtle finding on CT imaging, recirculation phenomenon in the maxillary sinus involves abnormal flow of mucus between neighboring openings into the maxillary antrum and is a common iatrogenic cause of persistent postsurgical CRS (see Videos 7.1 and 7.2). When present, this can often be observed on CT imaging as an opacification in and around the natural or accessory ostium (Fig. 7.1).¹⁰ Magnetic resonance imaging (MRI) is usually not necessary to evaluate the maxillary sinus, but MRI is sometimes useful as an adjunct to CT images when distinguishing between tumor, trapped secretions, and allergic fungal mucin.

Management of Suboptimal Prior Surgery

If initial evaluation of the patient reveals refractory disease secondary to suboptimal prior surgery or an iatrogenic process, then revision surgery may become necessary to address the problem. Prevention of these problems is fundamental and begins in the operating room to deter the formation of postoperative adhesions, which represent a common source of surgical failure with an incidence from 1 to 36%.¹¹ Many studies have evaluated the use of a variety of middle meatal packing both for hemostasis and adhesion prevention, and a recent review concluded that resorbable packs [FloSeal (Baxter, Deerfield, IL), Gelfilm (Pfizer Pharmaceuticals, New York, NY), Gelfoam (Pfizer)] have no added benefit over nonresorbable packing (Merocel; Medtronic, Mystic, CT) or no packing. In fact, some resorbable packing (Floseal, Gelfilm) had an increased risk of granulation tissue and adhesions, although it was not clear whether the resulting synechiae were clinically significant.¹¹ Noting that mitomycin C has been used in other fields to inhibit scar formation, several groups examined topical administration of this agent at the middle meatus to determine whether it would decrease the incidence of stenosis and synechiae. All three studies concluded that mitomycin C offered no significant reduction in stenosis or adhesions.^12–14

Aggressive postoperative cleaning and debridement also play an important role in preventing postsurgical maxillary CRS. Careful endoscopic inspection in the office should identify any middle meatal debris, crusting, or bone fragments which should be suctioned and removed to prevent an inflammatory reaction and adhesion formation. Localized adhesions between the middle turbinate and the natural ostia may be cut in the clinic with topical and local anesthesia if the patient is tolerant.

In addition to a residual uncinate process, a common cause of a persistent obstructed maxillary ostium was found to be a missed maxillary sinus ostia, which was not connected to the surgically created maxillary antrostomy.⁵ This iatrogenic posterior fontanelle antrostomy may result in the mucus recirculation phenomenon (Fig. 7.2). This can also occur when an inferior meatal antrostomy was created in addition to a middle meatal antrostomy to cause recirculation between the two openings. The treatment is surgical and leads to resolution of the abnormal mucus flow. The openings involved must be joined into one larger antrostomy by removing the bridge of bone or mucosa between the two. This can often be performed in the clinic with cutting instruments with topical and local anesthesia.¹⁵ In those patients with recirculation between middle and inferior meatal antrostomies, Coleman and Duncavage have described an extended middle meatal antrostomy that connects the two openings by creating a much larger antrostomy.¹⁶

One procedure that has a high rate of postsurgical failure is the Caldwell–Luc procedure, which usually entails removal of maxillary sinus mucosa. Long-term complications in post-Caldwell–Luc sinuses include abnormal mucociliary function, chronic neuralgia, infraorbital nerve injury, tooth root injury, and delayed mucocele.⁷ In their retrospective study of post-Caldwell–Luc patients with persistent disease, Han et al determined that surgical salvage with an endoscopic “mega-antrostomy” was an alternative to repeating the Caldwell–Luc procedure. The mega-antrostomy is created by endoscopically extending the maxillary antrostomy inferiorly to the nasal floor to facilitate sinus ventilation and postoperative irrigation given the disorganized mucociliary clearance in these sinuses.⁷ Woodworth et al also showed that 14 patients who had failed a Caldwell–Luc procedure were successfully treated with a modified endoscopic medial maxillectomy.¹⁷

Fig. 7.2 Endoscopic view of mucus recirculation in the same patient shown in Fig. 7.1. Thickened mucus is transported from the natural ostium (arrowhead) to the iatrogenic maxillary antrum (arrow).

Medical Management

Medical therapies for CRS in postsurgical patients are the same as for the treatment of all CRS patients and can be categorized into topical and systemic therapies ranging from topical saline and antiinflammatory agents to systemic antibiotics and steroids. The choice of medical therapy should be catered to the individual patient on the basis of the underlying pathology. Usually, the treatment is an integrated, multifaceted approach designed to reduce chronic sinus mucosal inflammation and infection. Adjuvant therapy in postsurgical CRS may include nasal saline, antibiotics, antifungals, topical and systemic steroids, antihistamines, decongestants, and topical biofilms inhibitors.

Nasal Saline

The practice of nasal irrigation with saline has a long history stemming from purification rites in ancient India in preparation for yoga. Topical delivery of saline via irrigations, sprays, and nebulizers has been intensively studied recently as an adjunct in the treatment of sinonasal inflammatory disease, and a recent Cochrane review concluded that saline irrigation is beneficial resulting in the improvement of symptoms of CRS.¹⁸ Several investigators have examined the effects of delivery device on penetrating the paranasal sinuses with varying results. Multiple studies have shown that large volume, positive pressure irrigations with syringes or squeeze bottles to be superior to atomizer, nebulizer, and spray in postsurgical sinus delivery,^19–21 and that these large volume irrigations are superior to sprays in reduction of symptom severity and frequency.²²

There is also growing evidence to support the intuitive claim that saline delivery is greater in the postoperative maxillary sinus compared with the preoperative state. In fact, Grobler et al calculated that a minimum ostial dimension of 3.95 mm is required to attain a 95% probability of topical irrigant penetration.²³ Harvey et al performed an irrigation study using radiocontrast dye in cadavers before surgery, after endoscopic sinus surgery, and after endoscopic medial maxillectomy. The delivery was with a pressurized spray, a squeeze bottle, or a neti pot, and they found that sinus distribution as measured by CT imaging was greater after sinus surgery with additional distribution gained after a medial maxillectomy. Furthermore, irrigation delivery was significantly greater via the neti pot and squeeze bottle techniques compared with the spray, and the neti pot offered the greatest distribution after surgery (see Video 7.3).²⁴

Based on these reviews and studies, saline irrigation via squeeze bottle or neti pot is recommended to who have postsurgical maxillary CRS. It is especially useful in the immediate postoperative period to help remove crusting and debris, which may contribute to inflammation.²⁰ This is easily tolerated by most patients and appears to improve overall symptoms. It is important to note, however, that patients should be instructed in the proper sterile care of their irrigation fluid and device to prevent bacterial colonization and possible subsequent infection.

Antibiotics

Although there is considerable variability in the usage of antibiotics and their duration, the microbiology of acute and chronic rhinosinusitis is well established, and the most common organisms cultured in CRS are both aerobes (Streptococcus pneumoniae, Staphylococcus aureus, coagulase-negative Staph) as well as anaerobes (Peptostreptococcus species).²⁵ However, evidence suggests that the microbiological environment of the maxillary sinus may be different in the postsurgical state. Brook and Frazier found that Pseudomonas aeruginosa and gram-negative aerobic bacilli were more often isolated in patients who had previous sinus surgery, and they showed that postsurgical patients had fewer anaerobic isolates.²⁶ Coagulase-negative Staph and S. aureus were also found to be common isolates in the postsurgical sinus.²⁷ Current evidence shows that bacteria contributing to CRS are exhibiting growing resistance to antimicrobial agents. There are more prevalent strains of S. pneumoniae resistant to penicillin, trimethoprim-sulfamethoxazole, and macrolides, and there is a documented increase in β-lactamase-producing aerobes.²⁵ A recent study also found that the rate of recovery of methicillin-resistant S. aureus (MRSA) from patients with acute and chronic sinusitis has increased from 2001 to 2003 and from 2004 to 2006.²⁸

Because of this variability in microbiology and the rise of antibiotic-resistant organisms, culture-directed therapy individualized to each patient is most likely to provide therapeutic benefit. We prefer culture-directed oral antibiotics administered for at least 3 weeks in addition to adjuvant therapies to reduce infection and inflammation (e.g., topical saline irrigations, antibiotics or steroids).

Antibiotics may also be administered topically in irrigated or nebulized form to deliver the agent directly to the infected mucosa of the postsurgical maxillary sinus. As with topical steroids, this greatly reduces systemic side effects of oral or parenteral antibiotics. Although there are no established clinical criteria for their use, they may serve as a therapeutic adjunct in patients who are recalcitrant to medical and surgical therapy. These patients with postsurgical CRS may suffer from persistent bacterial colonization in the maxillary sinuses secondary to poor mucociliary function, biofilm formation, or other innate host factors, and topical antibiotics may reduce the bacterial load.

One recent study evaluated evidence-based recommendations for topical antibiotic use to find that several agents have reasonable clinical evidence to justify their use: topical mupirocin, levofloxacin, clindamycin, tobramycin, and ceftazidime.²⁷ In one study of 16 postsurgical patients with persistent S. aureus infection, twice daily nasal lavages with 0.05% mupirocin (Bactroban; GlaxoSmithKline, Research Triangle Park, NC) improved endoscopic findings and yielded negative swab results for S. aureus after 3 weeks of treatment.²⁹ Mupirocin has been well studied for its topical activity against MRSA in the nose, and it is ideal as a topical agent because it exceeds the minimum inhibitory concentration (MIC) and retains its anti-Staphylococcus activity in nasal secretions for up to 8 hours.²⁷

Topical tobramycin is used often in patients with persistent P. aeruginosa sinusitis, which is common in cystic fibrosis. Aerosolized tobramycin has been well established in the treatment of pseudomonal pneumonia in cystic fibrosis patients, and several groups have adapted this to treat Pseudomonas-positive sinonasal cultures. One study found that topical tobramycin delivered to postsurgical sinuses via nasal lavage in cystic fibrosis patients resulted in a significant decrease in revision surgeries,30 although others have not found significant improvement with topical tobramycin.³¹

Topical antibiotics may serve to disrupt sinus biofilms as well. A biofilm is a structured community of organized bacterial cells that adhere to both inert and biologic surfaces.^32,33 Studies have begun to establish that biofilms may play a role in chronic sinusitis, although their exact mechanism in the pathophysiology of sinusitis remains elusive.³² Recent investigations have begun to associate biofilms with clinically significant sinus disease. Bendouah et al showed a correlation between the presence of P. aeruginosa and S. aureus biofilms and postoperative persistence of sinus disease.³⁴ In a retrospective study, Psaltis et al found that patients with biofilms had significantly worse postoperative symptoms and mucosal disease. Interestingly, the presence of fungus at the time of surgery also correlated with an unfavorable outcome in this study.³⁵ With increasing data supporting a role for biofilms in the pathophysiology of recalcitrant CRS, more studies are investigating agents that may disrupt biofilms including topical mupirocin, tobramycin, and moxifloxacin.^36–38

Topical agents to disrupt biofilms other than antibiotics are also being investigated. For instance, Chiu et al have found that the chemical surfactant baby shampoo delivered as a 1% solution in nasal irrigations for 4 weeks resulted in an improvement in subjective symptoms and in olfaction testing in postsurgical patients.³⁹

Antifungals

Like antibiotics, antifungal agents may be delivered systemically or topically. Intravenous antifungal therapies such as amphotericin-B and posaconazole have considerable systemic side effects (nephrotoxicity, hepatotoxicity), and these are usually reserved for the treatment of invasive fungal sinusitis. Oral itraconazole has been used as an adjunct in the treatment of allergic fungal sinusitis,⁴⁰ but given its poor therapeutic indices, costs, risks of hepatotoxicity and other systemic side effects, its relative therapeutic benefits should be carefully weighed.⁴¹

Topical antifungal therapy in the form of amphotericin B has been proposed in the treatment of allergic fungal sinusitis (AFS) as well as CRS. Fungus has been well established in the pathogenesis of AFS as outlined in the diagnostic criteria by Bent and Kuhn.⁴² AFS patients are atopic and often have nasal polyps and the allergic fungal mucin that is a rather specific finding for the disease; hence, these patients are usually treated with a combination of systemic or topical steroids as well as immunotherapy directed against fungal antigens. Endoscopic sinus surgery is often necessary for those patients with a large burden of polyp disease or allergic fungal mucin, especially if topical corticosteroids are to reach inflamed mucosa unobstructed.⁴¹

However, Ponikau et al have proposed that fungal infection is actually a pathologic mechanism in all forms of CRS by either direct infection or secondary inflammatory responses.⁴³ They demonstrated that fungal cultures were positive in 96% of CRS patients, and they subsequently found that treatment of 51 patients with CRS with topical irrigations of amphotericin-B for 3 months resulted in an improvement in CT and endoscopic findings, but there was no clinical improvement.⁴⁴ However, Weschta et al were not able to duplicate this finding in a double-blind randomized controlled trial of 60 patients with CRS (and excluding AFS patients).⁴⁵ The position that fungus is the sole mechanism of disease in CRS remains unproven. Most acknowledge the importance of fungus in sinus disease, but the pathogenesis is likely due to multiple etiologic mechanisms leading to the final common result of CRS. The therapeutic benefit of topical antifungals in AFS and CRS will remain controversial until further clinical trials are done.

Steroids

Intranasal and systemic glucocorticoid steroids have been widely used in the treatment of CRS, both before and after sinus surgery. Although many mechanisms may lead to CRS, the multiple actions of glucocorticoid steroids (e.g., reducing eosinophil mucosal infiltration, decreasing mucosal vascular permeability) make them ideal for treating everything from allergic rhinitis to nasal polyposis to postoperative mucosal edema.⁴⁶ The use of oral steroids has been found to reduce recurrence of disease, especially in AFS patients. In one retrospective study, oral steroid treatment in AFS patients showed clinical improvement after sinus surgery and reduced the time in between revision surgeries.⁴⁷ There were no reported adverse effects from long-term systemic steroid therapy in this study. However, side effects of oral steroids may potentially be severe and undesirable including immunosuppression, psychotropic effects, osteoporosis, diabetes mellitus, Cushing syndrome via suppression of the hypothalamic–pituitary axis, and aseptic joint necrosis. Oral steroids are therefore administered with caution and their use is tailored to the individual patient. Often a short tapering “burst” of oral steroids is necessary as an adjunct to irrigations or culture-directed antibiotics to alleviate postsurgical mucosal edema or to treat an acute exacerbation of CRS secondary to nasal polyps. Sometimes low-dose long-term oral steroid therapy may be necessary to prevent recurrent disease, but with careful consideration of their adverse effect profile.

Topical glucocorticoid steroids have a safer side-effect profile given their more limited systemic bioavailability, and the efficacy of steroid sprays has been well described in the long-term treatment of allergic rhinitis. Topical steroid sprays also have demonstrated improvement in symptom scores and nasal obstruction in the treatment of CRS with nasal polyposis.46 This class of medication remains a mainstay of treatment in postsurgical patients with AFS, CRS with polyposis, and those patients with persistent reactive hyperplastic mucosal edema.

Investigators have also studied other topical formulations of glucocorticoid steroids. Nebulized budesonide (Pulmicort Respules) has proven benefit in reducing pulmonary inflammation in the treatment of asthmatic patients. Lund et al found that budesonide delivered via an aqueous nasal spray also exhibited efficacy in allergic CRS patients.⁴⁸ Kanowitz et al demonstrated that topical budesonide delivered via an atomization device in postsurgical patients exhibited symptomatic relief and a reduction in the need for systemic steroids.⁴⁹ We recommend budesonide in nasal irrigations in many of our postoperative patients with AFS and polyposis who are refractory to other treatments.

Topical steroids may also be administered in the form of drops. DelGaudio and Wise reported their experience with topical steroid drops (dexamethasone ophthalmic, prednisolone ophthalmic, and ciprofloxacin-dexamethasone otic) in a cohort of CRS patients who had recent sinus surgery. The drops were anatomically directed with the head hanging off the bed (Mygind’s position) to the frontal sinuses in a majority of cases, although they did include one patient in whom they specifically addressed the maxillary sinus. They reported good success with 64% of their cases exhibiting persistent sinus patency, although there was one case of adrenal suppression from drop use.⁵⁰

Sinonasal polyps may also be treated with steroid injections in addition to systemic or topical steroids. Injection of nasal polyps with a steroid (e.g., triamcinolone acetonide) has been shown to be an effective adjunct treatment, although its use is typically guarded due to the rare, but reported complication of permanent visual loss. In a recent report, Becker et al demonstrated in a series of 358 patients that intrapolyp steroid injection compared with surgical excision was associated with a lower rate of complications.⁵¹ In the appropriate patient with nasal polyposis, intermittent steroid injections may play a role in controlling polyp disease.

Other Medical Therapies

Evidence supports the use of maximal medical therapy in the postsurgical patient before proceeding to a revision surgery. The treatment of CRS is as multifaceted as its pathogenesis, so a host of other therapies in addition to antibiotics and steroids is also necessary in some patients. Oral and topical decongestants may temporarily alleviate maxillary sinus obstruction, but their use is limited due to systemic side effects (e.g., hypertension). Long-term use of topical decongestants such as oxymetazoline and phenylephrine also carries the risk of abuse by the patient and rhinitis medicamentosa.

Other medications such as mucolytics and antihistamines may have a limited role in some postsurgical patients. Treatment with a mucolytic such as guaifenesin may alleviate the symptoms of thick nasal secretions. Antihistamines and leukotriene inhibitors have known therapeutic benefit in allergic rhinitis, and these may be recommended in CRS patients with concomitant atopic disease.⁵² Laryngopharyngeal reflux disease may play a role in CRS, although evidence in the literature is frequently conflicting. The treatment of reflux with proton-pump inhibitor therapy may certainly be required in a subset of recalcitrant CRS patients.⁵³

Allergy testing and possible immunotherapy should be considered in those CRS patients who may be refractory to medical and surgical therapy. In fact, immunotherapy to fungal antigens has become widely accepted as one part of the multifaceted treatment management for AFS patients.⁴¹

Another subset of challenging patients for the practicing rhinologist is the patient with cystic fibrosis. The incidence of CRS in these patients approaches 100%, and 10 to 20% eventually undergo sinus surgery.⁵⁴ Postoperative medical therapies are directed at clearing viscous mucous, maintaining sinus ostial patency, and reducing persistent bacterial colonization. Often these patients require multiple therapies including saline or steroid irrigations, topical and oral antibiotics, and oral steroids. Recent studies have shown encouraging results for some postoperative cystic fibrosis patients who received nasally inhaled dornase alfa, although further study is needed to evaluate its benefit.⁵⁵

Revision Sinus Surgery

When medical management of postsurgical maxillary sinusitis fails, revision surgery may become necessary. Between 2 to 18% of surgical patients require at least a second procedure for recidivistic disease.⁵ Patients with CRS with polyposis have a higher rate of refractory disease with one study demonstrating that 27% of these patients required revision sinus surgery to reduce their polyp burden.⁵⁶ It should be noted that these challenging patients should be thoroughly evaluated to rule out other mechanisms of disease. For instance, refractory maxillary disease may sometimes have odontogenic origin, most commonly from dental abscesses, but sometimes from unrecognized dentigerous cysts (Fig. 7.3), which may require surgical treatment.^57,58 Also refractory disease may be due to mucoceles of the maxillary sinus, which should be evident on careful endoscopic or radiographic evaluation. The treatment of these mucoceles is surgical excision resulting in very low rates of recurrence.⁵⁹

A full discussion of revision sinus surgery is outside the scope of this chapter, but many approaches have been described to address surgical failures of the maxillary sinus including the modified endoscopic medial maxillectomy,¹⁷ the canine fossa puncture,⁶⁰ and even the Caldwell–Luc procedure.⁶¹