 Images are moderately limited by patient motion. Postoperative changes are again seen from previous Chiari decompression with tonsillopexy. The cervical syrinx has significantly improved, now essentially collapsed, measuring 7 x 2 mm in greatest axial dimensions at the lower C6 level. It previously measured up to 6 mm AP at the same level on prior available sagittal cervical spine images. The syrinx was most conspicuous spanning the C2 and C3 levels where it measured up to 7 mm AP, now essentially barely visualized. Discontinuous syrinx remains visualized down to the lower C7 level, similar in extent to previous exam. Additional upper thoracic component is not well assessed on the current images, but likely is grossly similar.The fourth ventricle previously measured 3.2 cm AP on 4/19/2016, now only 2.1 cm. There is also slight decreased size of the fourth ventricle compared to the more recent 4/26/2016 exam. There is interval resolution of dorsal bulging of the upper cervical cord at the level of the neo-foramen magnum, with now well visualized dorsal CSF space caudal to the remaining cerebellar tissue. Previous heterogeneous signal dorsally at the level of the neo-foramen magnum has resolved, likely postoperative. Upon CSF flow imaging, biphasic flow is identified through the third ventriculostomy site into the prepontine cistern, as well as in the cerebral aqueduct, fourth ventricle, and minimally dorsal to the cervicomedullary junction, although flow is slightly asynchronous. There has been improvement in flow along the dorsal aspect of the upper cervical cord.A curvilinear structure is seen along the superior margin of the right lateral ventricle which may represent granulation tissue or debris, as it is located just deep to an area of linear hyperintensity in the overlying brain parenchyma suggesting a possible surgical tract. The previous ventriculostomy catheter has been removed. Lateral and third ventricles are grossly stable in size.
1.Previous ventricular catheter has been removed. Evidence of third ventriculostomy with biphasic flow through the surgical defect. Lateral and third ventricles are grossly stable in size, with interval decreased dilatation of the fourth ventricle.2.Interval expected evolution of postoperative changes at the neo-foramen magnum improved visualization of dorsal CSF space at this level. Previously noted subtle bulging of the upper cervical cord has resolved. Overall, improved visualization of biphasic CSF flow at this level.3.Significant improvement in cervical syrinx, with grossly similar upper thoracic component suggest, incompletely assessed.