Fungal rhinosinusitis and imaging modalities

Abstract

This report provides an overview of fungal rhinosinusitis with a particular focus on acute fulminant invasive fungal sinusitis (AFIFS). Imaging modalities and findings that aid in diagnosis and surgical planning are reviewed with a pathophysiologic focus. In addition, the differential diagnosis based on imaging suggestive of AFIFS is considered.

Keywords: Acute fulminant invasive fungal sinusitis; Computed tomography; Fungal rhinosinusitis; Imaging; Magnetic Resonance Imaging.

Figure 1

(A) 58 year-old female in diabetic ketoacidosis presents with decreased vision, chemosis, proptosis and ophthalmoplegia on the left side concerning for AFIFS. (B) Oral exam demonstrates poor dental hygiene and necrosis of the hard palate. (C) Endoscopic exam reveals necrosis of the left inferior turbinate which was removed during debridement. Tissue culture eventually grew Rhizopus microsporious. (D) Orbital exenteration was performed in conjunction with nasal and sinus debridement because of significant orbital involvement seen on imaging. Involvement of the ethmoid sinus air cells can be appreciated through the thin medial wall of the orbit.

Figure 2

Axial (A) and coronal (B) non-enhanced CT of AFIFS shows opacification of the left ethmoid, left maxillary sinus and left nasal cavity.

Figure 3

Axial non-enhanced CT of AFIFS demonstrates opacification of the left maxillary sinus with soft tissue inflammation of the premalar tissues (arrowhead) and of the retroantral fat (arrow).

Figure 4

Coronal T1 MR with gadolinium and fat suppression of AFIFS shows opacification of left maxillary and ethmoid sinuses with hypointense middle and inferior turbinates (straight arrow) and loss of contrast enhancement of the maxillary mucosa (arrowhead) and inferior rectus muscle (curved arrow).

Figure 5

Axial T1 MR with gadolinium and fat suppression of AFIFS demonstrates enhancement of the retroantral fat (arrow).

Figure 6

Axial T1 MR with gadolinium and fat suppression of AFIFS shows opacification of the left maxillary sinus with loss of contrast enhancement of the sinus wall, premalar tissues (straight arrow), retroantral fat (curved arrow) and of the lateral wall of the nasal cavity (arrowhead) which likely correlates to tissue necrosis.

Figure 7

Coronal non-enhanced CT of granulomatosis with polyangitis demonstrates a homogenous soft tissue mass extending into the left orbit with erosive changes of the left nasal cavity, ethmoid and maxillary sinuses resulting in septal perforation and bony erosion of the maxilla.

Figure 8

Coronal T2 MR of sinonasal squamous cell carcinoma shows a large mass involving the nasal cavity, bilateral ethmoid sinuses and left maxillary sinus with infiltration into the left orbit.

Figure 9

Axial CT with contrast of granulomatous invasive fungal rhinosinusitis demonstrating opacification of the ethmoid sinuses and fat stranding of the intraconal space of the right orbital apex.

Figure 10

Axial CT of allergic fungal rhinosinusitis shows bilateral involvement of the ethmoid and sphenoid sinuses filled with hyperintense mucin and evidence of sinus expansion and bone erosion. (Courtesy of William Dillon, MD and Songling Liu, MD.)

Figure 11

Coronal T2 MR of a fungus ball of the sphenoid sinus demonstrates low signal intensity (arrow). (Courtesy of William Dillon, MD and Songling Liu, MD.)