Pediatric Sinusitis Surgery

Surgical management of chronic sinusitis has 2 distinct eras in the past 50 years, before and after discovery of the true physiologic way that the sinuses clear secretions. In Europe in 1978, Messerklinger authored a book describing research demonstrating that the physiological flow of secretions in the sinuses was to their respective ostia or openings. ^[7] Cilia on the mucosal lining of the sinuses push secretions on top of a mucociliary blanket toward the natural opening, attempting to clear them into the nasal cavity and down the pharynx, eventually to be swallowed into the stomach. Based on this research, functional endoscopic sinus surgery (FESS), now commonly known only as endoscopic sinus surgery (ESS), was developed.

Prior to introduction of the physiological flow of the sinuses, surgery was aimed at removing ethmoid air cells, opening up the sphenoid widely, opening up the maxillary sinus via a Caldwell Luc or inferior meatal window, and possibly removing the middle turbinate. This was performed with a headlight and big forceps. With the innovation of the Hopkins rod telescopes and xenon light sources in the late 1960s and early 1970s, visualization in the nasal cavity was much improved. Surgeons became more interested in the intricate anatomy of the sinuses and lateral nasal wall. New techniques were developed to make the surgery safer and more successful. A new area of study was established.

Endoscopic sinus surgery (ESS) has been practiced for more than 2 decades. It began in Europe with techniques described by Messerklinger and Wigand. The Messerklinger technique involves initially opening up the anterior area where the sinuses drain, the ostiomeatal complex (OMC), which appears to be the bottleneck for disease. If this area can be opened, the sinuses may be able to ventilate and drain, keeping them clear of disease.

A second area of drainage is into the sphenoethmoid recess where the posterior ethmoids and sphenoid drain. Surgery is aimed at clearing out the ethmoid cells and opening up the sphenoid ostia. In a 1981 report, Wigand described increased access to this area by removing the posterior portion of the middle turbinate, thereby allowing for increased exposure during surgery and decreased obstruction after surgery. ^[8]

Several surgeons began to popularize Messerklinger's technique; the most noticeable was his pupil, Heinz Stammberger. Stammberger promoted the Messerklinger technique in Europe and then in America with Kennedy in 1985 and 1986. ^{[9, 10, 11, 12, 13]} Several pediatric otolaryngologists, including Lusk, Lazar, and Gross began performing ESS in children in 1986. Since that time, numerous articles and books have discussed the general technique of ESS, as well as specific techniques for specific sinuses and their ostia. A wider range of instrumentation for endoscopic sinus surgery (ESS) has been introduced with various opinions and results.

Overall, sinus surgery for chronic sinusitis has been proven to be effective in appropriately selected patients when the main goal of any particular technique is to open and aerate the sinuses where they naturally drain. Endoscopic sinus surgical techniques have been used successfully for other diseases of the nasal cavity and sinuses, including nasal polyposis, nasal tumors, and suppurative complications of sinusitis.

Sinusitis is defined as an infection of one or more of the paranasal sinuses. It implies the stasis of secretions in the affected sinus, usually caused by a bacterial infection. Sinusitis occurs when the outflow tract of the sinus is blocked, fluid becomes trapped, and fluid becomes infected with bacteria.

Frequency

The frequency of sinusitis is difficult to estimate because, throughout the literature, definitions are conflicting. If the loosest definition is accepted (ie, infection and inflammation of the nasal cavity and paranasal sinuses caused by bacteria and viruses), 1 billion cases of acute sinusitis have been estimated to occur in the United States each year, affecting at least 30% of the population, with a health care expenditure of 2.2 billion dollars on prescription and nonprescription drugs. Most acute cases of rhinosinusitis are viral, whereas chronic sinusitis is more often bacterial, requiring long-term medical therapy, or eventually, surgery. According to the National Ambulatory Medical Care Survey, if an adult is sick enough with rhinosinusitis symptoms to seek care from a physician, a bacterial infection is present 50% of the time.

Children, however, more often have viral infections with sinonasal symptoms, with bacteria present 10-20% of the time. Sinusitis is often observed in children with allergic rhinitis, and 10-25% of children around the world are estimated to have allergic rhinitis, reviewing data from Germany, Italy, Japan, Norway, Poland, Sweden, and Britain. In 1994, Wright estimated that 42% of children in the United States had seasonal rhinitis. The number of children who then proceed to surgical drainage of the sinuses is not well defined. ^[14]

The cause of acute or chronic sinusitis is obstruction of the outflow tracts of the individual sinuses, usually because of mucosal edema. The main outflow tract of the sinuses, especially the anterior sinuses (which are most commonly affected), is through the OMC near the ethmoid cavity and middle turbinate. Mucosal edema may arise from chemical or environmental irritants (eg, secondhand smoke, allergic rhinitis, chronic infections in the nasal cavity).

Similarly, if the mucociliary blanket does not function, as in children with immotile cilia syndrome or CF, secretions cannot be cleared, causing obstruction of the outflow tract of the sinuses with stasis of secretions and chronic infection. The most common bacteria observed in chronic sinusitis are Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, alpha-hemolytic streptococci, Staphylococcus aureus, and rarely, anaerobes. Anaerobes are more often observed in adults with chronic sinusitis.

The nasal cavity and paranasal sinuses are lined with pseudostratified ciliated columnar epithelium. The cilia on the lining are encased in a mucociliary blanket that beat in specific directions to move mucous and particulate matter through the nasal cavities and sinuses. Cilia in the sinuses beat toward their ostia. If inflammation of the mucosa of the outflow tracts of the sinuses occurs, whether from infection, allergic reaction, or irritation, the mucosal surfaces can come into contact with one another. For any mucosal surface, contact results in obstruction of the sinus and localized disruption of the mucociliary clearance. This leads to relative negative pressure in the sinus, stasis of secretions, and sinusitis. Therapy, whether medical or surgical, is aimed at decreasing this mucosal contact and opening up the sinuses, allowing them to ventilate and drain.

Maximal medical therapy is aimed at decongesting the mucosa of the outflow tracts to open up the sinuses, as well as to directly treat the infecting bacteria with antibiotics. If ventilation cannot be accomplished medically, surgical intervention may be indicated. For the endoscopic technique, surgery is aimed at removing the bony obstruction at the sinus outflow tracts. Once widened, mucosal edema arising from allergic reactions, upper respiratory infections, or chemical irritants hopefully will not be severe enough to result in obstruction. The actual size of the ventilation opening needed to prevent sinusitis is unknown.

A retrospective study by Brown et al looked at the histopathologic differences in sinonasal tissue between adults and children with chronic rhinosinusitis. The investigators reported that while 28.9% of the adults had tissue neutrophilia, the same was true in just 12.0% of pediatric patients. Moreover, 70.3% of adults demonstrated basement membrane thickening, compared with 44.0% of children. A significantly greater share of adults was also found to have subepithelial edema, squamous metaplasia, and eosinophil aggregates. A lymphoplasmacytic-predominant inflammatory background existed in 66.5% of the adults, while a lymphocyte-predominant inflammatory background occurred in 57.8% of the children. ^[15]

Children with sinusitis present with persistent or recurrent purulent rhinorrhea or postnasal drainage resulting in cough, nasal congestion, maxillofacial pressure and pain, and occasionally fever and/or headaches. The most common signs are purulent rhinorrhea and cough. Chronic conditions are usually present for 3 months. Recurrent sinus infections may clear between episodes, and clinical symptoms of the sinus infection and nasal airway obstruction may clear. Purulent rhinorrhea in children is confusing. Purulence (yellow or green color) is derived from dead granulocytes that may or may not have arisen while fighting a bacterial infection. Purulent rhinitis can be the result of a viral infection, sinusitis, or adenoiditis.

Additional important information can be obtained from the physical examination. In young children, the initial physical examination of the nasal cavity is performed with an otoscope. Often, the inferior turbinate can be visualized, and the middle turbinate and lateral nasal wall in the area of the OMC can be visualized as well. If the inferior turbinate is large and the mucosa is pale, suspect allergic rhinitis. If the mucosa is erythematous and purulence is observed in the middle meatus, suspect a bacterial infection. Fever and maxillary sinus tenderness increases the suspicion for a bacterial infection. If the nose anteriorly looks clear overall but nasal congestion is encountered along with purulent rhinitis, suspect adenoiditis. For purulent rhinitis that lasts longer than a week or 10 days, with prolonged fever (temperature >102°F) or with maxillofacial pressure and pain, treat with antibiotics.

Purulent rhinorrhea, nasal congestion, and cough in toddlers to preteens warrant consideration of viral upper respiratory infection, adenoiditis, and sinusitis. If a child has had these symptoms repeatedly, requiring multiple courses of antibiotics, direct initial evaluation at the possibility of allergic rhinitis causing sinusitis, an enlarged and chronically infected adenoid, and chronic paranasal sinusitis. If adenoid hypertrophy is diagnosed, especially in the absence of allergic rhinitis, adenoidectomy is the first indicated surgical procedure (see Adenoidectomy).

In older children with signs and symptoms of chronic sinusitis and small adenoids, initial surgical options are more confusing. Some evidence supports that adenoidectomy alone does not improve the disease and that endoscopic sinus surgery (ESS), combined with adenoidectomy, is an appropriate initial surgical approach. Regardless, endoscopic sinus surgery (ESS) for chronic or recurrent sinusitis is indicated only when maximum medical therapy is unsuccessful.

A clinical consensus statement on pediatric chronic rhinosinusitis, from a nine-member panel of otolaryngologists assembled by the American Academy of Otolaryngology-Head and Neck Surgery Foundation (AAO-HNSF) Guidelines Task Force, listed the following statements regarding adenoidectomy ^[16] :

• Adenoidectomy is an effective first-line surgical procedure for children up to age 6 years with chronic rhinosinusitis

• Adenoidectomy is an effective first-line surgical procedure for children aged 6-12 years with chronic rhinosinusitis

• Adenoidectomy can have a beneficial effect independent of endoscopic sinus surgery, in patients with pediatric chronic rhinosinusitis

• Tonsillectomy (without adenoidectomy) is an ineffective treatment for pediatric chronic rhinosinusitis

For children, maximal medical therapy is usually defined as treatment with several 3-week courses of antibiotics and adjuvant medicine to decongest and clear the nasal cavity and OMC. Antibiotics should be directed at the most common pathogens of sinusitis, including S pneumoniae, H influenzae, and M catarrhalis. Other important bacteria cultured from the sinuses at the time of endoscopic sinus surgery (ESS) include alpha-hemolytic streptococci, S aureus, and rarely, anaerobes. Anaerobes are more often observed in adults with chronic sinusitis.

Adjuvant medicine to decongest and clear the nasal cavity and OMC should include oral decongestants, oral and intranasal antihistamines, isotonic and hypertonic nasal saline sprays and irrigations, nasal steroid sprays, histamine stabilization sprays, and expectorants. Screen and treat underlying medical conditions, such as allergic rhinitis, cystic fibrosis (CF), immunodeficiency, and dysfunctional ciliary syndromes if present and treatable. Consider endoscopic sinus surgical therapy for chronic sinusitis only after a thorough evaluation has been performed and proper adequate medical treatment has been administered.

However, certain medical conditions may warrant immediate endoscopic surgical intervention. A suppurative complication of acute or chronic sinusitis (eg, brain abscess, meningitis, orbital abscess) requires correction of the complication and surgical eradication of disease in the affected sinus. ^{[17, 18]}  Tumors or other lesions of the sinus may mimic sinusitis and warrant removal or biopsy for diagnosis.

Sphenoid sinus

Controversy exists over whether or not to enter the sphenoid when it displays chronic sinusitis without polyposis on CT scan. In a 1996 report, Smith declared that, for cases of chronic sinusitis, eradication of ethmoid disease results in spontaneous resolution of sphenoid disease, inciting caution for formally entering the sphenoid sinus. ^[19] For polypoid disease or lesions in the sphenoid sinus, surgical approaches must be considered.

Frontal sinus

Indications for pediatric frontal sinus surgery are similar to indications for adult surgery and include chronic sinusitis, frontal sinus polyposis, acute sinusitis unresponsive to 24-48 hours of appropriate antibiotics, and suppurative complications of sinusitis. A particularly interesting and not uncommon entity observed in teenagers with no history of chronic sinusitis is intracranial complications from acute frontal sinusitis. ^{[20, 21]} Initial presentation of these teenagers may consist only of a few days of nasal drainage, with subsequent fever and neurologic changes. Often, sinusitis is unilateral, occurring in the anterior ethmoids, frontal sinus, and occasionally, maxillary sinus.

A combined neurosurgical and otolaryngic approach must be coordinated to remove disease. The mucosa of the nose and sinuses is inflamed and infected. This can lead to increased bleeding and decreased visualization. In this situation, an external approach to the frontal sinus via a Lynch incision is recommended to drain the purulent fluid.

Nasal polyposis

Consider endoscopic sinus surgery (ESS) for children with nasal polyposis refractory to nasal steroids, short-course oral steroids, or leukotriene inhibitors. Nasal polyposis may be observed in patients with cystic fibrosis (CF), allergic fungal sinusitis, chronic sinusitis, or other types of lesions or tumors of the nose (see Nasal Polyps). In patients with CF and nasal polyposis, a dilemma arises concerning indications for surgery. CT scans in patients with CF almost uniformly show disease. Hallmarks include bulging of the medial maxillary wall with frequent mucocele formation of the maxillary sinus.

Most authors believe that patients should have surgery when they are symptomatic. In a 1996 report, Nishioka advocated that patients with CF who feel that they are asymptomatic or minimally symptomatic are unaware of the potential improvement because they have adapted to a subpar clinical state secondary to their disease. ^[22] Once their disease is exonerated, they realize that their nasal airflow is increased, their ability to smell exists, and their food tastes better. They also become aware of their appropriate baseline.

Repeat surgery is not uncommon in patients with CF. With the advance of the surgical microdebrider, revision surgery can be performed quickly, precisely, and safely. In a 1997 article, Mendelsohn reported that the microdebrider greatly decreased the recurrence rate. ^[23] Patients with CF who have surgery for symptomatic relief uniformly state that they would do it again.

Before successful endoscopic sinus surgery (ESS) can be performed in children, knowledge of the anatomy, physiology, and development of the nasal cavity and paranasal sinuses must be understood. The basic relationships of the anterior ethmoids and middle meatus, including the uncinate process, ethmoid infundibulum, hiatus semilunaris, and bulla ethmoidalis, are present at birth. These are relatively constant landmarks throughout life. Most of the change involves growth and pneumatization of these sinuses and the lateral nasal wall. Most of the growth for the sphenoid and frontal sinuses occurs later, from 4-14 years of age.

Infants are born with maxillary and ethmoid sinuses. The number of ethmoid air cells, ranging from 3-15 cells per side, rarely changes over a child's life. However, the cells themselves increase in size and pneumatize rapidly in the first 3-4 years of life. At birth, the maxillary sinus represents a shallow sac in the lateral nasal wall, developing rapidly in the first 4 years of life. By age 4 years, the maxillary sinus has expanded laterally to the infraorbital canal and inferiorly to the attachment of the inferior turbinate.

At birth, the sphenoid sinus is a blind mucosal sac that does not reach the sphenoid bone or cartilage, and the frontal sinus is not present. By age 4 years, the frontal sinus begins to expand from the frontal recess, and the sphenoid sinus is the size of a pea but is easily identifiable. From age 4-8 years, the ethmoid growth slows. By age 7 years, the maxillary sinus floor extends to the middle of the inferior meatus. At this age, the floor of the nose is still lower than the floor of the maxillary sinus, and the permanent teeth have not all erupted. A Caldwell Luc procedure or inferior meatal window performed in preschool aged children could damage permanent tooth buds. The sphenoid and frontal sinuses continue to expand in this developmental period.

For the most part, the final stages of development and pneumatization of the paranasal sinuses occurs from age 8-14 years, roughly equaling adult size. The maxillary sinus now has expanded to the floor of the nose and beyond. Over the next 10 years, some minor increases in pneumatization may occur, and the sphenoid sinus may change slightly in configuration.

Because the relationships of the paranasal sinuses stay relatively constant, surgical techniques for sinus surgery stay relatively similar throughout a child's life, especially for the anterior ethmoid and maxillary sinuses. Technically, it can be performed in young children. The author has endoscopically drained a subperiosteal abscess in a 7-week-old infant, opening up the lamina papyracea relatively widely to allow drainage. Although the lateral nasal wall landmarks were similar in position to older children, the ethmoid bulla and lamina papyracea appeared slightly higher in its relationship to the middle turbinate.

Knowledge of the endoscopic anatomic relationships of the nasal cavity, lateral nasal wall, and paranasal sinuses is extremely important to perform successful surgery and prevent complications. When endoscopic sinus surgery techniques were developing, certain aspects of the anatomy of the lateral nasal wall were named differently. In order to clearly define paranasal sinus anatomy and unify terminology, an international conference on sinus disease for terminology, staging, and therapy was held in July 1993. Most all of the leaders in endoscopic sinus surgery were present. The endoscopic sinus surgeon must be familiar with this anatomy in all age groups.

The only absolute contraindication to surgery is the inability to undergo general anesthesia. A relative contraindication to surgery is an incomplete workup or inadequate maximum medial therapy.