Headache. The cerebellar tonsils extend up to 5 mm inferior to the foramen magnum, but display rounded morphologies. The posterior fossa capacity appears to be relatively small. There is no evidence of intracranial hemorrhage, mass, or acute infarct. The brain parenchyma and pituitary gland appear unremarkable. 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 are grossly unremarkable.
1. The cerebellar tonsils extend up to 5 mm inferior to the foramen magnum, but display rounded morphologies, and the posterior fossa capacity appears to be relatively small. MRI with CSF flow study may be useful for further evaluation of potential Chiari I malformation.2. No evidence of acute intracranial hemorrhage, mass, or acute infarct.