Headaches and right leg weakness. The right cerebellar tonsil extends up to 4 mm inferior to the foramen magnum and the posterior fossa appears slightly small in capacity. There is no evidence of intracranial hemorrhage, mass, or acute infarct. The brain parenchyma and pituitary gland appear unremarkable. There is no abnormal intracranial enhancement. The ventricles and basal cisterns are normal in size and configuration. There is no midline shift. The major cerebral flow voids are intact. The orbits, paranasal sinuses, and scalp soft tissues are grossly unremarkable.
The right cerebellar tonsil extends up to 4 mm inferior to the foramen magnum and the posterior fossa appears slightly small in capacity, which raises the possibility of mild Chiari type 1 malformation. No evidence of intracranial hemorrhage, mass, or acute infarct. 