29-year-old woman with history of Chiari malformation and headache. The cerebellar tonsils are low lying with peglike morphology, with caudal descent approximately 6mm inferior to the foramen magnum. There is crowding of the cervicomedullary junction. Normal, biphasic CSF flow is seen ventrally. Diminished, biphasic flow is seen posteriorly. There is no restricted diffusion to suggest acute ischemia. No intracranial hemorrhage. No intracranial mass or mass-effect. There is no hydrocephalus. The major flow-voids are preserved.Sella and orbits are grossly within normal limits. There is a small amount of fluid and frothy secretion in bilateral maxillary sinuses, sphenoid sinus, and ethmoid air cells. There is also a right maxillary mucosal retention cyst. Bone marrow signal and extracranial soft tissues are within normal limits. CERVICAL SPINE
1.Chiari 1 malformation with diminished biphasic CSF flow posteriorly at the cervicomedullary junction.2.No evidence of syrinx in the cervical cord.3.Bilateral paranasal sinus air-fluid levels and frothy secretions which may represent acute sinusitis in the appropriate clinical setting. 