E1700. No One Knows: Key Imaging Features of Fungal Sinonasal Disease
  1. Tucker Burr; Loyola University Medical Center
  2. David Serrano; Loyola University Medical Center
  3. Mariah Bashir; Loyola University Medical Center
This exhibit will explore imaging features of fungal sinonasal disease, which may be classified as non-invasive or invasive. Non-invasive disease is composed of allergic fungal disease and mycetoma. These are postulated to be caused by deficient clearance leading to fungal germination/replication and an inflammatory response, presenting incidentally or with mild sinus pressure. Surgical excision is often curative. Invasive disease may be further characterized as acute, chronic, or granulomatous. It is important to distinguish acute invasive fungal rhinosinusitis as this may rapidly progress within hours to days with vascular invasion and a very high mortality. This is seen in immunocompromised patients: diabetes (infected with Zygomycetes sp.), hematologic malignancy (Aspergillus), chronic steroid use. Patients present with facial swelling, congestion, orbital symptoms, CN palsy. Treatment is radical debridement until normal tissue reached.

Educational Goals / Teaching Points
Imaging is important to diagnosis, and understanding anatomy of the sinuses and adjacent spaces is integral to assessing disease. Using specific cases, key clinical and imaging findings will be demonstrated to differentiate invasive and non-invasive sinonasal fungal sinusitis. There will be correlation with operative findings to enhance understanding of the imaging findings and the pathophysiology behind invasive and non-invasive disease.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
Important anatomic landmarks will be reviewed including the periantral fat plane (anterior & posterior), the septum, pterygopalatine fossa with the sphenopalatine foramen, lacrimal sac, and nasolacrimal duct. CT is preferred for complications of sinusitis, particularly sub-periosteal abscess orbital extension. MRI is preferred for assessing intracranial extension including brain abscess, subdural empyema, and sinus thrombosis.

Imaging integral to diagnosis of fungal sinus disease. Distinct imaging features correlated with gross macroscopic intraoperative findings allow for accurate diagnosis and treatment. CT and MRI have complementary roles in the evaluation of extrasinus extension, secretion content, and osseous changes. Non-invasive disease may manifest with aggressive features including extension beyond the paranasal sinuses and osseous erosion. Acute invasive disease is often characterized by subtle findings that are easily overlooked.