Achondroplasia. Brain: There are stigmata of achondroplasia involving the skull, including frontal bossing, hypoplasia of the skull base, and narrowing of the foramen magnum, which measures a minimum of 9 mm in the anteroposterior dimension. However, there is no compression of the cervicomedullary structures and cerebrospinal flow is preserved anteriorly across the foramen magnum. There is susceptibility effect in the bilateral occipital lobe peritrigonal white matter, as well as gyriform or sulcal susceptibility effect in the occipital lobe. There is no evidence of intracranial mass or acute infarct. There are prominent subarachnoid spaces overlying the bilateral frontal convexities and the ventricular system is borderline prominent, along with a cavum velum interpositum. There is no midline shift or herniation. The major cerebral flow voids are grossly intact. The orbits, paranasal sinuses, and scalp soft tissues are grossly unremarkable.Cervical Spine: There is diffuse congenital narrowing of the cervical spinal canal, but no compression of the spinal cord. The vertebral column alignment is within normal limits. The vertebral body and disc space heights are preserved. The vertebral bone marrow signal is unremarkable. The spinal cord displays normal signal and morphology. The paravertebral soft tissues are unremarkable.
1. Stigmata of achondroplasia involving the skull with foramen magnum stenosis, but no compression of the cervicomedullary structures.2. Prominent subarachnoid spaces overlying the bilateral frontal convexities and the ventricular system is borderline prominent, which could indicate underlying impedence to cerebrospinal fluid resorption.3. Susceptibility effect in the bilateral occipital lobe peritrigonal white matter, as well as gyriform or sulcal susceptibility effect in the occipital lobe likely represents sequela of remote hemorrhage. 