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Chronic Sinus Congestion
This case features a patient presenting with chronic sinus congestion, ultimately diagnosed with arrested pneumatization of the skull base.
Imaging overview:
Axial and coronal non-contrast CT of the paranasal sinuses demonstrates a well-defined, nonexpansile lesion in the basisphenoid with sclerotic, well-defined margins, internal fat attenuation, and curvilinear calcifications, characteristic of arrested pneumatization.
Clinical insight:
Arrested pneumatization of the skull base is a benign developmental variant that occurs at sites of normal pneumatization within the basisphenoid or adjacent skull base. On CT, it classically appears as a well-circumscribed lesion with internal fat and curvilinear calcifications, reflecting incomplete conversion of fatty marrow during the normal pneumatization process. Recognizing this entity is essential, as its imaging appearance can mimic more aggressive lesions such as chordoma or metastasis. It is considered a “do not touch” lesion requiring no further workup or intervention when classic imaging features are present.
Case courtesy of Jennifer Joyce, DO,
Medical University of South Carolina