eMedicine Specialties > Otolaryngology and Facial Plastic Surgery > Nasal & Sinus Diseases

eMedicine Specialties > Otolaryngology and Facial Plastic Surgery > Nasal & Sinus DiseasesSinusitis, Maxillary, Chronic, Surgical Treatment

Sinusitis affects approximately 35 million people annually in the United States, with an attendant medical cost of $5.8 billion annually.

In adults, the maxillary sinuses are most commonly affected with acute and chronic sinusitis. Most of these cases can be managed with medications alone. For the instances where medical management fails, surgery may be needed to treat chronic maxillary sinusitis.

For excellent patient education resources, visit eMedicine's Ear, Nose, and Throat Center and Eye and Vision Center. Also, see eMedicine's patient education articles Sinus Infection and Eye Pain.

History of the Procedure

Open approaches to the maxillary sinus were first described in the early 1700s. The well-known Caldwell-Luc operation was first described in the United States by George Walter Caldwell in 1893 and then by Henri Luc of France in 1897. Subsequent advances in the understanding of the physiologic drainage pattern of the maxillary sinus led to intranasal middle meatus antrostomy in the late 1960s and the early 1970s. Functional endoscopic sinus surgery (FESS) is based on the surgical approach performed by Messerklinger and Wigand in Europe via the ostiomeatal complex.1,2 FESS has become the standard surgical treatment for chronic maxillary sinusitis, with external approaches being used as an adjunct in more complicated cases or in tumor management.

Problem

In 1996, the American Academy of Otolaryngology-Head & Neck Surgery convened a multidisciplinary Rhinosinusitis Task Force (RTF). This group defined adult rhinosinusitis diagnostic criteria. In 2003, this definition was amended to require confirmatory radiographic or nasal endoscopic or physical examination findings in addition to suggestive history. The following paragraphs provide a summary of these criteria.

Rhinosinusitis is a group of disorders characterized by inflammation of the mucosa of the nose and paranasal sinuses. Chronic rhinosinusitis is rhinosinusitis of at least 12 consecutive weeks' duration. The 1996 diagnostic criteria, as defined by the RTF, required 2 or more major factors or 1 major factor and 2 minor factors. Major factors for diagnosis include facial pain or pressure, nasal obstruction or blockage, nasal discharge or purulence or discolored postnasal discharge, hyposmia or anosmia, purulence in nasal cavity, and fever (for acute rhinosinusitis only). Minor factors were defined as headache, fever (for chronic rhinosinusitis), halitosis, fatigue, dental pain, cough, and ear pain, pressure, or fullness. Of note, facial pain requires another major factor associated with it for diagnosis (facial pain plus 2 minor factors is not deemed sufficient for diagnosis of rhinosinusitis).

The 2003 diagnostic criteria for chronic rhinosinusitis require the above criteria for longer than 12 weeks or more than 12 weeks of physical findings. In addition, one of the following signs of inflammation must be present:

Discolored nasal drainage from the nasal passages, nasal polyps, or polypoid swelling as identified on physical examination with anterior rhinoscopy after decongestion or nasal endoscopy

Edema or erythema of the middle meatus or ethmoid bulla on nasal endoscopy

Generalized or localized erythema, edema, or granulation tissue (If the middle meatus or ethmoid bulla is not involved, radiologic imaging is required to confirm a diagnosis.)

Imaging modalities confirming the diagnosis include the following:

CT scanning demonstrating isolated or diffuse mucosal thickening, bone changes, or air-fluid levels OR

Plain sinus radiography revealing air-fluid levels or greater than 5 mm of opacification of one or more sinuses

MRI not recommended for routine diagnosis because of its excessive sensitivity and lack of specificity

In general, plain radiography has low sensitivity and specificity. CT scanning is considered the imaging standard for evaluation of chronic sinusitis.

Etiology

See Future and Controversies.

Pathophysiology

Much remains to be elucidated about the pathophysiology of chronic maxillary sinusitis. The main theory lies in obstruction at the level of the ostiomeatal complex leading to stasis and infection of secretions within the maxillary sinus. Obstruction may occur secondary to any number of inciting factors including upper respiratory tract infection (viral, bacterial, or fungal), allergic rhinitis, trauma, or prior surgery.

Presentation

Chronic maxillary sinusitis is defined as sinusitis lasting longer than 12 weeks. Suggestive history as above may include chronic facial pressure (maxillary region), headache, rhinorrhea, postnasal drip, decreased sense of smell, or dental pain. Confirmatory findings on the physical examination include intranasal edema, purulence, or rhinorrhea. Other etiologies for headache and rhinitis should be ruled out because migraine, tension headache, or allergic rhinitis can mimic chronic sinusitis. Often, allergic rhinitis may be observed in conjunction with chronic sinusitis.

Preoperative workup should include a complete history and physical examination along with CT scanning of the paranasal sinuses. The physical examination should include a nasal endoscopy with a culture and/or biopsy if needed. Screening CT scanning (3- to 5-mm direct coronal cuts) can be used for clinical diagnosis. Thereafter, surgical CT scanning may be obtained for finer anatomic detail and preoperative planning.

Indications

Surgery for chronic sinusitis is reserved for those patients who did not respond to medical therapy. Medical treatment should include 3-6 weeks of antibiotics, nasal steroids, and nasal saline irrigations. Antibiotics should be chosen after cultures are obtained endoscopically if possible. Oral steroids are used if significant nasal edema is observed on nasal endoscopy. A short course of decongestants and mucolytics should be considered for patients with significant nasal congestion and thick nasal secretions.

CT scanning should be obtained to confirm clinical suspicion of chronic sinusitis. Findings may include significant mucosal thickening, air-fluid levels, ostiomeatal complex obstruction, polyposis, or calcification suggestive of fungal sinusitis.

Relevant Anatomy

EmbryologyThe maxillary sinus is present at birth, undergoing further expansion with age. Two main points of rapid growth occur, from birth until age 3 years and then from age 7 years through early adolescence. The sinus then slowly grows until it reaches adult size by age 18 years. Later in adult life, the sinus continues to pneumatize inferiorly and may expand to contain tooth roots. The average size of the maxillary sinus is 34 mm X 33 mm X 23 mm, with an average volume of 14.75 mL. In an adult, the floor of the maxillary sinus is below the level of the nasal floor.

AnatomyAn understanding of the lateral nasal wall anatomy is critical to performing safe and effective endoscopic sinus surgery.

The maxillary sinus is housed in the body of the maxilla, with the inferior orbital wall as the superior border, the lateral nasal wall as the medial boundary, the alveolar process of the maxilla as its inferior border, and the canine fossa as the anterior border.

The main functional component of the maxillary sinus outflow tract is the ostiomeatal complex, which is collectively constituted by the uncinate process, the maxillary ostium, the infundibulum, and the ethmoid bulla. These structures form a functional complex through which the maxillary sinus contents egress. Obstruction of the ostiomeatal complex and its relief with surgery form the basis for FESS.

The uncinate process is a sickle- or L-shaped bone that starts anterosuperiorly and then slopes posteroinferiorly, running horizontally from anterior to posterior. It has a free edge along its superior surface, which is taken down during uncinectomy. Superiorly, the uncinate process may attach to the lamina papyracea (most common configuration), the middle turbinate, or the skull base. At its most posterior point, it attaches to the inferior turbinate at the ethmoidal process.

Once the uncinate process is taken down, the natural maxillary sinus ostium can be visualized. The cilia of the maxillary sinus beat uphill toward the natural maxillary sinus ostium. Therefore, the natural ostium of the maxillary sinus must be included with maxillary antrostomy for maximal functional benefit. If the natural ostium is missed, mucus recirculation may be a problem. The ethmoid bulla lies just posterior to the uncinate process and may be visible along with the uncinate process on routine nasal endoscopy. The ethmoid bulla is the most constant anterior ethmoid air cell.

Contraindications

No absolute contraindications to endoscopic surgical treatment of chronic maxillary sinusitis exist.

Workup

Laboratory Studies

Suggested - CBC

Consider - Prothrombin time (PT), activated partial thromboplastin time (aPTT), radioallergosorbent test (RAST), pregnancy test, and electrolytes, depending on the patient's medical history

Imaging Studies

A CT scan of the paranasal sinuses should be obtained. A thorough review of preoperative CT scanning is required to check for the following:

Position of the lamina papyracea in relation to the uncinate process

Position of the skull base and the nasolacrimal duct

Presence of a hypoplastic maxillary sinus with or without an atelectatic uncinate process

Dehiscence of the lamina papyracea or the skull base

Diagnostic Procedures

Suggested - Nasal endoscopy, vision test

Consider - Acoustic rhinometry, smell test

Treatment

Medical Therapy

Medical therapy is the first-line treatment of chronic sinusitis. It should consist of a 3- to 6-week course of oral antibiotics (eg, fluoroquinolone or macrolide, a broad-spectrum penicillin class drug with beta lactamase inhibitor), steroids, and nasal saline irrigations. If significant intranasal edema is observed on endoscopic examination, a course of oral steroids (7-28 d, depending on severity) may serve as a useful adjunct therapy. Consider a short course of decongestant to provide symptomatic relief for patients with symptoms of significant nasal congestion. High doses of guaifenesin (600 mg PO bid) may also be beneficial as a mucolytic for patients with tenacious nasal secretions.

Culture-directed antibiotics may be used based on endoscopically obtained cultures of middle meatus mucopurulence, if empiric antibiotics have already failed.

Surgical Therapy

Surgery is reserved for patients with confirmed chronic sinusitis, as documented by findings on history, physical examination findings, and CT findings, who have not responded to medical therapy.

Three main surgical options are available: (1) endoscopic uncinectomy with or without maxillary antrostomy, (2) Caldwell-Luc procedure, and (3) inferior antrostomy (naso-antral window).

Today, endoscopic maxillary antrostomy and uncinectomy are the standard for treatment of refractory chronic maxillary sinusitis. The Caldwell-Luc and inferior antrostomy approaches are reserved for rare circumstances (an example may be a case of severe allergic fungal sinusitis where standard antrostomy alone does not allow complete extirpation of fungal concretions or complete drainage).

Additionally, further FESS with mucosal sparing techniques may be performed if additional disease is present within the ethmoid, sphenoid, and frontal sinuses.

Preoperative Details

Consent should be obtained prior to any surgical procedure. This should include a thorough discussion of possible risks such as orbital injury, blindness, nasolacrimal duct injury, epiphora, epistaxis, cerebrospinal fluid leak, meningitis and brain abscess, and of course persistent rhinosinusitis.

A preoperative antibiotic course may be administered in the weeks prior to surgery if an active infection is present. A preoperative steroid course may be administered if significant edema or polyps are observed on examination.

Intraoperative Details

Endoscopic maxillary antrostomy

Before entering the operating room, the surgeon should select, inspect, and prepare all instrumentation, including image guidance devices. In the preoperative holding area, nasal decongestion is begun with the patient receiving sprays of oxymetazoline. Following the commencement of general endotracheal anesthesia, the eyes are protected with eye ointment and thin strips of tape. The nasal passages are decongested with appropriate vasoconstrictors such as topical cocaine if not medically contraindicated.

If septoplasty is to be performed, the septum should be infiltrated with 1% lidocaine with 1:100,000 epinephrine in the submucochondrial plane. Then, the patient is draped and prepared for surgery. A 4-mm 0- or 30-degree endoscope may be used, depending on the surgeon's preference. If septoplasty is to be performed, it may be done either before or after sinus surgery. Place the septoplasty incision in the unobstructed nasal passage to allow better visualization of the more obstructed side.

Under endoscopic guidance, the middle turbinate may be gently moved medially, with care to avoid fracturing the turbinateskull base junction. At this point, the uncinate process should be within view, and it is injected with 1% lidocaine with 1:100,000 epinephrine. Local injections can be made using a 10-mL control syringe with a luer lock 27-gauge needle attached. First, the root of the uncinate process is injected. Next, the inferior portion of the uncinate process is injected. The root of the middle turbinate is infiltrated as well. Finally, an injection is placed at the inferior junction of the basal lamella with the lateral nasal wall. This serves to vasoconstrict the sphenopalatine artery. Approximately 1-2 mL of local anesthetic is used at each injection site, with the bevel down (toward mucosa). An appreciable blanche of the mucosa should be observed with each injection.

If using an image-guided system, it can be calibrated at this time (thereby giving time for vasoconstriction from the injections to take effect). Alternatively, the system may be calibrated prior to beginning the case. When using an image-guided system, checking the position of the guidance tracking in a few different known points and confirming the accuracy in 3 dimensions is important. Typically, for isolated chronic maxillary sinus disease, image-guided surgery is not necessary.

After decongestion, uncinectomy is the next step. Uncinectomy can be performed in numerous ways. The following is the authors' preference. Under endoscopic guidance, a maxillary ostium seeker is insinuated just behind the uncinate process and carefully used to outwardly and anteriorly displace the free edge of the uncinate. Care is taken to only very gently manipulate the uncinate process and not to penetrate deeply to prevent lamina papyracea injury.

Next, 90-degree upbiting forceps are used to grasp the free edge of the uncinate process. In a controlled push and pull fashion, staying parallel to the lacrimal duct, the uncinate process is then removed. Care is taken to engage the uncinate process parallel to the lateral nasal wall to prevent injury to the lamina papyracea. Any remaining uncinate process may be removed using a combination of microdebrider powered instrumentation and pediatric forceps. All portions of the uncinate should be taken down completely to permit visualization of the natural maxillary sinus ostium, roughly parallel to the inferior portion of the middle turbinate.

Once the natural ostium is identified, an ostium seeker can be placed through the ostium and then carefully pushed posteriorly to widen the ostium. Using a through-cutting forceps, the ostium is enlarged, thereby completing a maxillary antrostomy. The maxillary sinus should be inspected with a 30- or 70-degree scope to ensure that no further disease is present within the sinus and that the natural ostium was included in the antrostomy. If either a microlith or a polyp is present, it may be removed using curved giraffe forceps or a curved suction. Further endoscopic work can be performed if disease is present in other sinuses.

If lateralization of the middle turbinate is a concern and to allow easier postoperative examination of the maxillary antrostomy in the office, the controlled synechiae technique as described by Bolger et al in 1999 may be used. Briefly, this involves abrading the opposing areas of mucosa from the medial middle turbinate and septum. With healing, the two roughened areas appose, thus medializing the turbinate for improved postoperative visualization of the maxillary sinus antrostomy.

The middle meatus may be packed with various products if either postoperative bleeding or lateralization of the middle turbinate is a concern. Many packing materials have been described, ranging from rolled Gelfilm to Merocel packing. The authors' preference is for a latex-free glove-covered trimmed Merocel in the middle meatus. This should be removed at the first postoperative visit (3-5 d).

Caldwell-Luc procedureFor patient comfort, this procedure is typically performed under general anesthesia. However, if medical comorbidities preclude general anesthesia, the procedure may be performed with local anesthetic and sedation. It may be performed in conjunction with nasoantral window (inferior antrostomy) to facilitate postoperative surveillance.

Lidocaine, 1% with 1:100,000 epinephrine, is injected in the incision site, and time is allowed for vasoconstriction. Make a 3-cm incision centered over the canine tooth and first premolar while leaving about 0.5-1 cm of gingiva intact above the dentition to facilitate closure. Using electrocautery, dissection is carried down through the soft tissue and periosteum to bone. Next, a periosteal elevator is used to widely elevate periosteum from the anterior wall of the maxilla. Care is taken to identify and avoid injury to the infraorbital nerve, which is vertical and inferior to the mid pupillary line. In the canine fossa, with mallet and osteotome, the maxillary sinus is entered through its anterior thin bone. Thereafter, rongeurs are used to enlarge the opening. Any pus from the maxillary cavity may be sent for culture. The disease within the sinus can be appropriately addressed. Next, the sinus is irrigated. The incision is then closed using 3-0 or 4-0 absorbable suture.

Inferior antrostomyVasoconstriction is begun with topical oxymetazoline on pledgets. Next, 1% lidocaine with 1:100,000 epinephrine is injected under endoscopic guidance along the lateral nasal wall underneath the inferior turbinate. A 3-mL syringe with a 27-gauge needle facilitates the injection. Because the nasolacrimal duct lies approximately 1 cm anterior to the natural maxillary ostium, the injection and surgical antrostomy site is about one to two thirds of the distance back along the inferior turbinate. Next, the maxillary sinus is punctured in this region using a curved suction or trocar. This antrostomy should then be enlarged with through-cutting forceps. The maxillary sinus disease should then be extirpated as appropriate.

Postoperative Details

The stomach and nasopharynx should be suctioned prior to extubation. The surgeon should confirm with the anesthesiologist that an appropriate antiemetic was administered during surgery.

After extubation, the patient is taken to the postoperative care unit for recovery. Once the patient is awake, the patient is examined to check extraocular motility and to check for evidence of excessive bleeding or proptosis. If the patient is doing well, he or she may be discharged home after all postanesthesia protocol parameters have been satisfied.

Follow-up

Postoperative care of the patient with chronic sinusitis is essential for long-term success. The patient is sent home with appropriate pain medications and instructions for nasal saline irrigations.

The patient returns for the first postoperative visit 3-5 days after surgery. At this time, the middle meatus packing is removed and all crusts and dried blood clots are carefully dbrided. Weekly follow-up may be needed for the first month, and then biweekly follow-up with dbridements may be indicated for the second month. After the second month, the patient is usually monitored quarterly for the first year. Further follow-up is then determined by the severity of the patient's disease, healing, and symptoms.

Further medical management after surgery with antibiotics, nasal steroids, antihistamines, allergy medications, and oral steroids is individualized based on the patient and further flares of sinusitis.

Complications

Pitfalls

Several studies have been conducted to elucidate the common causes of failure in FESS. These may include incomplete uncinectomy or failure to include the natural maxillary sinus ostium within the antrostomy and thereby creating recirculation between two ostia. Lateralization of the middle turbinate or turbinate remnant and postoperative synechiae formation are also common. These pitfalls may be carefully avoided by performing a complete uncinectomy, identifying and enlarging the true maxillary sinus ostium, being gentle with medialization of the middle turbinate, and using a mucosal-sparing technique with through-cutting instrumentation to avoid excess mucosal stripping.

Postoperative nasal endoscopic debridement is critical to decrease scarring and synechiae formation. The mucosa of the maxillary sinus should not be stripped routinely. The mucosa should be left intact because the mucosa that replaces stripped areas is devoid of proper ciliary function. This contributes to postoperative problems with mucus stasis and recurrent infection.

Occasionally, either secondary to scar band formation or in association with inferior antrostomy, recirculation may occur. This refers to the recirculation of maxillary sinus contents out of the natural ostium, along the mucosal band, and then back into the surgical antrostomy, thus creating an endless cycle of mucus build-up. To correct this, the intervening band of mucosa should be taken down to enlarge the antrostomy and to eliminate the cause of the recirculation.

Complications

Endoscopic maxillary antrostomyComplications of endoscopic surgery for chronic maxillary sinusitis may include orbital injury, blindness, orbital hematoma, nasolacrimal duct injury, epiphora, and postoperative epistaxis. Skull base injury and cerebrospinal fluid leak are very rare possible complications that should be discussed with patients undergoing endoscopic sinus surgery. With simple maxillary antrostomy, however, the risk of skull base injury should be negligible.

Caldwell-Luc procedureThe main complications associated with the Caldwell-Luc procedure include oroantral fistula, infraorbital nerve injury with associated hypesthesia, and injury to the tooth roots.

Inferior antrostomyThe main risk associated with inferior antrostomy is nasolacrimal duct injury. Recirculation of mucus from the natural maxillary ostium through the newly created inferior antrostomy is possible. This usually occurs when inferior turbinate reduction is also performed.

Outcome and Prognosis

Outcomes with properly selected patients for FESS have been outstanding. In 1989, Kamel reported a 96.8% patency rate for 94 endoscopic maxillary antrostomies (follow-up: 4-12 mo).3 Of his 66 patients, 95.5% had subjective improvement in their symptoms. In 1993, Salam and Cable reported long-term 89% patency rate of 90 maxillary antrostomies with statistically significant improvements in headache, nasal obstruction, and pain with a 26-month mean follow-up.4 Revision surgery is required in about 10% of cases.

Future and Controversies

Much remains to be discovered about the pathophysiology of chronic rhinosinusitis. Interesting work in the field is implicating an immunologic component in a large subset of patients with chronic rhinosinusitis. A heterogeneous group of patients seems to be lumped under the umbrella diagnosis of chronic rhinosinusitis without differentiation. Further work is needed to better characterize the different subsets of these patients to enhance understanding of the causes of rhinosinusitis and better optimize outcomes for people with this disease.

Another area of controversy is whether FESS is useful for patients with history and physical examination findings that are consistent with recurrent or chronic sinusitis but who have relatively normal findings on CT scanning. Little information exists in the literature regarding the optimal management of these patients with no abnormality detected on CT scanning, but one study with a very limited number of subjects demonstrated preliminary improvement in a very select group of patients without significant disease based on CT scan findings. Presently, this subset of patients is thought to be a very small minority of patients with chronic rhinosinusitis, and every effort should be made to confirm the diagnosis of chronic sinusitis and to prescribe a comprehensive course of medical treatment, including allergy treatment and saline, before resorting to surgical treatment.

Balloon catheter technology has been used to dilate the maxillary sinus natural ostia without bone or soft tissue removal. Early reports show persistent patient symptom improvement and sinus ostia patency. Further study and long-term outcomes with this technology will determine its role in endoscopic sinus surgery.5

The benefits of surgery should always outweigh the risks, a ratio that is only elucidated via a thorough workup and evaluation that includes careful consideration for conservative therapy.

Multimedia

(Enlarge Image)Media file 1: Endoscopic view right nasal cavity; lacrimal bone (L), uncinate process (U), ethmoid bulla (B), middle turbinate (MT), nasal septum (S).

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Endoscopic view right nasal cavity; lacrimal bone (L), uncinate process (U), ethmoid bulla (B), middle turbinate (MT), nasal septum (S).

(Enlarge Image)