Headache. The cerebellar tonsils extend up to 5 mm inferior to the foramen magnum and the posterior fossa appears to be relatively small. Nevertheless, the cerebellar tonsils display rounded morphologies. 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, skull, paranasal sinuses, and scalp soft tissues are grossly unremarkable.
1. The cerebellar tonsils extend up to 5 mm inferior to the foramen magnum and the posterior fossa appears to be relatively small, which may represent a mild form of Chiari type 1 malformation. 2. No evidence of intracranial hemorrhage, mass, or ventriculomegaly. 