Female, 33 years old, with bilateral frontal headaches. The cerebellar tonsils are ectopic descending proximally 4 mm below the level of the foramen magnum. As a result, the foramen magnum is slightly crowded.Elsewhere, brain parenchymal morphology is within normal limits. No pathologic parenchymal signal abnormality is seen. No abnormal parenchymal or extra-axial enhancement is detected. Diffusion-weighted images are within normal limits. No evidence of intracranial hemorrhage or any abnormal extra-axial fluid collection is seen. The ventricles are normal in size and morphology.Trace mucosal inflammation is seen within the paranasal sinuses.
1.Cerebellar tonsillar ectopia with mild crowding of the foramen magnum.2.No other significant intracranial abnormality.3.Trace paranasal sinus mucosal inflammation.