The significance of computed tomography in invasive paranasal mucormycosis

Introduction: Early diagnosis of acute invasive fungal rhinosinusitis (AIFR) is crucial for patient’s prognosis and may reduce the extent of surgical debridement. Initial evaluation usually includes paranasal Computed Tomography (CT), with an emphasis on bony erosion which is considered a specific but insensitive radiologic sign. Most studies made no distinction between Aspergillus and Mucor species while addressing CT findings. In this study, we seek to evaluate whether bony erosion on paranasal CT is a significant and reliable finding in the initial evaluation of invasive paranasal mucormycosis. Methods: A retrospective review of pre-operative non-contrast craniofacial CT scans of patients diagnosed with acute invasive fungal rhinosinusitis (AIFR) caused by Mucor species for the presence of bony erosion. Results: A total of 13 patients (9 males, 4 females) were included. Twelve patients were immunosuppressed due to various hematological malignancies. Six patients underwent debridement due to gross intraoperative findings of bony fungal invasion, but only one patient had evidence of bony erosion on the pre operative paranasal CT. Conclusion: Bony erosion on paranasal CT is an exceptionally insensitive radiologic sign for establishing or rejecting the diagnosis of Mucor induced AIFR. The mainstay of confirming or rejecting the diagnosis of AIFR is by physical examination, endoscopy and oriented biopsy of suspicious mucosal lesions.