Macrocephaly, the possibility of hydrocephalus, and a history of papilledema in the setting of chromosome 4 duplication: new headaches. There is persistent mild prominence of the ventricular system and cerebral convexity subarachnoid spaces. There is no evidence of intracranial hemorrhage, mass, or acute infarct. There is mild crowding of tissue at the foramen magnum, but the cerebellar tonsils are not low-lying. The brain parenchymal signal appears unremarkable, with an appropriate degree of myelination. There is no midline shift. The major cerebral flow voids are intact. The orbits, paranasal sinuses, and scalp soft tissues are grossly unremarkable. However, the calvarium is elongated in the anteroposterior dimension, while the central skull base appears to be hypoplastic. The optic apparatus slopes inferiorly anterior to the optic chiasm.
1. Persistent mild prominence of the ventricular system and cerebral convexity subarachnoid spaces, but no evidence of intracranial hemorrhage, mass, or acute infarct.2. Mild crowding of tissue at the foramen magnum, but the cerebellar tonsils are not low-lying. 3. The calvarium is elongated in the anteroposterior dimension, while the central skull base appears to be hypoplastic. 