The brain parenchyma appears normal without evidence of acute infarct or hemorrhage (within limits of non-contrast CT). No intracranial focal lesion. Age related diffuse cerebral involution and ventricular dilation is appreciated.
There is a well-defined rounded hypodense lesion seen in the right maxillary sinus with thin and smooth walls, consistent with a mucous retention cyst. This of similar size when compared to past imaging. The paranasal sinuses are otherwise unremarkable, and the nasal septum is midline.
The adjacent bony structures appear normal, and there is no evidence of bone erosion or thickening.
Impression:
A mucous retention cyst in the right maxillary sinus. No acute intracranial pathology.