Proposed computed tomography severity index for the evaluation of invasive fungal sinusitis: Preliminary results

Figure 3 Severe disease with computed tomography severity index 18 (50-year-old male, coronavirus disease 2019 positive with periorbital pain, left eye vision loss and cranial nerve palsies). The patient was a known diabetic with an HbA1C of 12.2. Microbiological evaluation revealed Rhizopus species. A-C: Axial contrast-enhanced computed tomography (CT) images show bilateral disease involving bilateral maxillary sinuses and nasal cavities (asterisk in A) with involvement of right posterior antral fat and pterygopalatine fossa (PPF; arrow in A). There is soft tissue infiltration in the left orbital fat extending to the left inferior orbital fissure (IOF; asterisk in B) with evidence of thickening of the left globe wall along with tenting of the posterior pole of the globe giving a classical guitar pick appearance suggesting the involvement of the left globe (arrow in C); D-F: Coronal CT images show erosion of the hard palate (arrow in D), fat stranding in the left orbit and thickening and irregularity of the left optic nerve (arrow in E). There is evidence of soft tissue infiltration in the left cavernous sinus (dotted arrow in F) with focal narrowing of the cavernous segment of left internal carotid artery (ICA; arrow in F). The total summated computed tomography severity index, in this case, is 18 (1 point each for paranasal sinuses and nasal cavity involvement, 2 points for significant bilateral disease, 1 point for the involvement of posterior antral fat, 1 point for hard palate erosion, 1 point for orbital soft tissue involvement, 2 for PPF/IOF involvement, 3 points for globe involvement, 3 points for cavernous sinus involvement and 3 points for ICA narrowing). Left exenteration was done due to extensive disease and intravenous amphotericin was given. Clinically, the patient did not respond well to the treatment, and repeat imaging was done 10 weeks later.