Clinical question: Chiari and tethered cord, history of decompression and cord repair OSH. Still with symptoms. Signs and symptoms: Unexplained cognitive and growths delay, headaches and back pain. Nonenhanced total spine MRI:Examination demonstrates expected post operative changes of Chiari decompression with resultant expansion of subarachnoid space at the level of surgery. There is no detectable herniation of cerebellar tonsils or tonsillar deformity identified.The signal intensity and the caliber of the entire cord remains within normal and in particular without evidence of syrinx. The cord terminates at L1 -- L2 disk level. The morphology and the signal intensity of the cauda equina is within normal and in particular no evidence of fatty filum present.Sagittal T2 prone images demonstrate distinct anterior movement of the lower thoracic cord, conus and proximal cauda equina compared to sagittal T2 supine images.There is subtle postoperative changes of prior surgical approach for untethering of the cord at S1 level.Unremarkable nonenhanced total spine MRI otherwise.3-D fiesta sequence demonstrate patency of the aqueduct however there is mild narrowing of the lumen of the aqueduct in its most cephalad aspect.CSF flow study demonstrate presence of biphasic flow anteriorly through the foramen magnum.The biphasic flow pulsation posteriorly to the cord terminates at the level of foramen magnum and there is no detectable biphasic flow posterior to the cerebellar tonsils, ventricle or in the aqueduct.
1.Expected postoperative changes of Chiari decompression and without evidence of tonsillar herniation or deformity.2.Normal signal intensity and caliber of cor and with normal termination at L1 -- L2 disk level.3.Distinct anterior movement of the conus and proximal cauda equina on prone sagittal T2-weighted series.4.Very subtle postoperative changes of cord untethering at S1 level as detailed above.5.Normal signal intensity of cauda equina and in particular without evidence of any fatty deposition of the filum.6.CSF flow study demonstrate presence of a normal appearing biphasic flow through the foramen magnum anterior to the cord. The biphasic flow of CSF posterior to the cord however terminates at the level of the foramen magnum. There is no detectable flow posterior to the cerebellum, fourth ventricle or the aqueduct. 