Complications
Local complications
Mucoceles are chronic epithelial cysts that develop in sinuses in the presence of either an obstructed sinus ostium or minor salivary gland duct. They have the potential for progressive concentric expansion that can lead to bony erosion and extension beyond the sinus.
Maxillary sinus mucoceles are usually found incidentally on sinus radiographs and are of little significance in the absence of symptomatology or infection. Surgical treatment is not usually necessary, and these lesions often regress spontaneously over time.
Frontoethmoidal and sphenoethmoidal mucoceles, on the other hand, tend to be symptomatic and have a high potential for bony erosion. Frontoethmoidal mucoceles should be completely removed and the sinus obliterated. Sphenoethmoid mucoceles should be widely opened into the nasal cavity.
Osteomyelitis is a potential local complication most commonly occurring with frontal sinusitis. Osteomyelitis of the frontal bone is called a Pott puffy tumor and represents a subperiosteal abscess with local edema anterior to the frontal sinus. This can advance to form a fistula to the upper lid with sequestration of necrotic bone. This rare complication should be managed with a combination of systemic antibiotics, surgical drainage of affected sinuses, and debridement of necrotic bone.
Orbital complications
Orbital complications are the most common complications encountered with acute bacterial sinusitis. Infection can spread directly through the thin bone separating the ethmoid or frontal sinuses from the orbit or by thrombophlebitis of the ethmoid veins. Diagnosis should be based on an accurate physical examination including ophthalmological evaluation and appropriate radiological studies. CT scanning is the most sensitive means of diagnosing an orbital abscess, although ultrasound has been found to be 90% effective for diagnosing anterior abscesses. [22] The classification by Chandler, which is based on physical examination findings, provides a reasonable framework to guide management. This classification consists of 5 groups of orbital inflammation [23] :
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Group 1 - Inflammatory edema (preseptal cellulitis) with normal visual acuity and extraocular movement
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Group 2 - Orbital cellulitis with diffuse orbital edema but no discrete abscess
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Group 3 - Subperiosteal abscess beneath the periosteum of the lamina papyracea resulting in downward and lateral globe displacement
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Group 4 - Orbital abscess with chemosis, ophthalmoplegia, and decreased visual acuity
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Group 5 - Cavernous sinus thrombosis with rapidly progressive bilateral chemosis, ophthalmoplegia, retinal engorgement, and loss of visual acuity; possible meningeal signs and high fever
A retrospective study by Cushen and Francis found that the occurrence of orbital cellulitis in association with the acute sinusitis is rare. The investigators reported the incidence to be 1.50 per 10,000 acute sinusitis episodes. Moreover, antibiotic administration in acute sinusitis was not linked to a significant change in the incidence of orbital cellulitis. [24]
Medical management, including sinus drainage and intravenous antibiotics, is advocated for any degree of orbital complication. The use of decongestant and antibiotic therapy is discussed in the Medical Care and Medication sections.
Among the classifications by Chandler, surgical drainage of both the infected sinuses and the orbit are advocated for groups 3-5 if inadequate improvement or progression of orbital cellulitis occurs despite medical therapy or if the patient has loss of visual acuity. Surgical procedures are discussed in Surgical Care.
Intracranial complications
Intracranial complications may occur as a result of direct extension through the posterior frontal sinus wall or through retrograde thrombophlebitis of the ophthalmic veins. Subdural abscess is the most common intracranial complication, although cerebral abscesses and infarction that result in seizures, focal neurological deficits, and coma may occur. Intracranial complications of sinusitis should be managed surgically with drainage of both the affected sinus and the cranial abscess.
Subdural empyema is a life-threatening infection that may complicate acute sinusitis. Boto et al (2011) reported the case of a previously healthy 10-year-old girl who developed subdural empyema due to Gemella morbillorum infection after an untreated maxillary, ethmoidal, and sphenoidal sinusitis. [25] Despite immediate drainage of the empyema and treatment with broad-spectrum antibiotics, she developed frontal cerebritis and refractory intracranial hypertension, needing urgent decompressive craniectomy. She recovered gradually with slight right-sided hemiparesis and aphasia.
The aforementioned study by Cushen and Francis found that even without antibiotic treatment, the occurrence of brain abscess in association with acute sinusitis is rare. The investigators reported the incidence of brain abscess following acute sinusitis to be 0.11. Moreover, although antibiotic use in acute sinusitis reduced the odds of brain abscess, the number needed to treat to prevent a single case was 19,988. [24]
Systemic complications
Sinusitis can result in sepsis and multisystem organ failure caused by seeding of the blood and various organ systems. Reports of bacteremia, thoracic empyema, and nosocomial pneumonia have been documented in the intensive-care population with acute sinusitis, and the mortality rate in this group can be as high as 11%. Fukushima et al (2012) reported on a case of a 39-year-old man admitted for the onset of acute purulent meningitis. [26] A cerebrospinal fluid culture grew Streptococcus sanguis. Sinusitis was found to be the cause of the meningitis. Treatment with intravenous antibiotics was successful.
Patient Education
For excellent patient education resources, see eMedicineHealth's patient education article Sinus Infection.
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Air-fluid level (arrow) in the maxillary sinus suggests sinusitis.