The left sinonasal expansion and signal pattern is due to dense fungal infection. The diagnosis was confirmed by the histopathologic evaluation of biopsy specimens.

MRI is the modality of choice to assess fungal sinusitis and its soft tissue extension. The findings within the sinus are variables such as mucosal thickening, polyp formation and complete opacification of the sinus. The characteristic finding in MRI  is a drop of signal intensity on T2 weight images.  

MRI is important in the detection of complications such as dural enhancement, intracranial extension, and periorbital extension. Good history-taking and physical examination combined with computed tomography, MRI, and nasal sinus endoscopy are important for the diagnosis of fungal sinusitis.

Management must be early with aggressive medical and surgical treatment. Systemic antifungal should be administered and diabetic ketoacidosis or neutropenia should be corrected. Aggressive surgical debridement is usually required.