Legend Axial T2, coronal T1WI. There is a heterogeneous mass with its epicenter in the posterior right ethmoid and sphenoid air cells with extension into the superior nasal cavity and left posterior ethmoid. Fluid/fluid levels are present in the anterior aspect of the lesion, and mass effect on the right medial rectus muscle is also noted. On the coronal image, there is erosion of the cribriform plate and intracranial extension.

Legend Axial, sagittal and coronal T1WI post gadolinium. There is slightly heterogeneous enhancement of the mass. Images confirm extension into the right medial orbit, superior orbital fissure, and anterior cranial fossa.

Legend Axial and coronal contrast-enhanced CT images reveal a mixed lytic-sclerotic lesion with intralesional ossification. Key words: mri ct tumor neoplasia sinus

ENT Diagnosis: Osteogenic sarcoma of ethmoid and skull base