Imaging findings of the orbital and intracranial complications of acute bacterial rhinosinusitis

Abstract

In patients with acute bacterial rhinosinusitis severe orbital and intracranial complications can occur. This review will illustrate the anatomic relationship between the paranasal sinuses and the orbital and intracranial compartments. Subsequently, the spectrum of orbital and intracranial complications of rhinosinusitis and related imaging findings will be discussed and illustrated by case material from daily practice.Teaching Points• Acute bacterial rhinosinusitis can cause severe orbital and intracranial complications.• If orbital or intracranial complications are suspected, cross-sectional imaging is mandatory.• Infection can spread from the ethmoid sinus to the orbit through the lamina papyracea.• Frontal sinusitis can spread intracranially through dehiscences or osteomyelitis.• Radiologists must recognize imaging findings of complications of acute bacterial rhinosinusitis.

ACR Appropriateness Criteria ® Sinonasal Disease

“…If there is clinical concern for orbital or intracranial complications, both CT and MRI may be necessary to better define the soft-tissue structures, orbital contents, and brain to guide appropriate treatment, with radiation exposure as low as reasonably achievable [46]. Infection from the ethmoid sinus can spread through the perforations of the lamina papyracea and cribriform plate; through the valveless veins, which extend to the cavernous sinus; and via direct extension in osteomyelitis.…”

“…CT scanning provides the best delineation of bone integrity or erosion. A contrast-enhanced CT may be an alternative in the setting of MRI contraindications to evaluate for intraorbital or intracranial complications [46]. Dual-phase imaging (without and with contrast) is not necessary.…”

Skull Base–related Lesions at Routine Head CT from the Emergency Department: Pearls, Pitfalls, and Lessons Learned

“…Sinonasal infections caused by bacteria such as Pseudomonas aeruginosa or invasive fungal agents like Aspergillus or Zygomycetes are commonly diagnosed in immunocompromised patients (15,16). CT is often the first modality performed to diagnose bony involvement and intracranial extension (15,17), which can result either from direct extension or by valveless communicating veins. In addition, the frontal sinus has bony dehiscences, structural abnormalities that can channel the spread of infection (16,17).…”

“…CT is often the first modality performed to diagnose bony involvement and intracranial extension (15,17), which can result either from direct extension or by valveless communicating veins. In addition, the frontal sinus has bony dehiscences, structural abnormalities that can channel the spread of infection (16,17). Patients can present with headaches, photophobia, seizures, or focal neurologic signs (16).…”

“…Complications include subdural and epidural empyema, cerebritis, brain abscess, and meningitis ( Fig 6), which are often neurosurgical emergencies (16). Osteomyelitis of the frontal bone can spread outward and form a subgaleal abscess described as Pott puffy tumor (16,17). Polyposis with secondary fungal infections can erode into the ASB, which can develop into meningitis or cause CSF leaks (15,18).…”