Fig. 6

Sinonasal involvement of ROCM. Unenhanced coronal T1W image (a) reveals diffuse, intermediate signal intensity, mucosal and mucoperiosteal thickening (thick arrows) in the nasal cavities and the maxillary sinuses, respectively. Note the slight asymmetric thickening of the right medial rectus muscle (thin arrow). Unenhanced axial T1W image (b) reveals mucoperiosteal thickening in the ethmoid and sphenoid sinuses with mild T1 shortening in the right sphenoid sinus (dotted arrow), consistent with fungal paramagnetic content. Axial T2W image (c) reveals non-specific, mixed signal intensity signals within the ethmoid and sphenoid sinuses. CE FS coronal T1W image (d) shows lack of enhancement in both middle turbinates and the right inferior turbinate (black turbinate sign—arrow heads), along with non-enhancing mucoperiosteal thickening in the maxillary sinuses (thick arrow). Note the asymmetric enhancement of the right medial rectus muscle (thin arrow) suggesting myositis. CE FS axial T1W image (e) confirms poor enhancement of the right ethmoid and sphenoid sinus mucoperiosteal thickening (thick arrows). Post-operative histopathology analysis (f), using HE staining, demonstrates shows few branching, aseptate fungal hyphae (thick arrow) consistent with the diagnosis of MCR along with neutrophilic and histiocytic inflammatory infiltrates (dotted arrow) and necrotic tissues (*)