Clinical question: History of Chiari decompression and syrinx. Evaluate for change to CSF flow. Signs and symptoms: Yearly follow-up. Nonenhanced cervical MRI:Postoperative changes of suboccipital decompression with persistent mild crowding of cerebellar tonsils remain identical to prior exam.Examination redemonstrates a short segment expansile syrinx of cervical cord traversing from C4 to C7 without significant change in size. It measures at approximately 41.3 mm compared to prior study measurements of 39.7. The largest transaxial dimensions of the syrinx is at T6 level and measuring at 8.5 in transverse and 6.6-mm in AP axis. This is compared with prior study measurements of 7.9 x 6.4-mm. There is no detectable signal abnormality of the cord immediately surrounding the syrinx.CSF flow study demonstrate normal biphasic flow through the foramen magnum anteriorly and posteriorly as well as through the fourth ventricle and the aqueduct. Considering the technique difference between the two exam there is no convincing evidence of change.
1.Revisualization of stable postoperative changes of Chiari decompression.2.Revisualization of expansile syrinx of the cervical cord which measures at 8.5 x 6.6-mm compared to prior study measurements of 7.9 x 6.4-mm. 3.CSF flow study similar to prior exam demonstrate presence of biphasic flow through the foramen magnum both anterior and posteriorly as well as through the fourth ventricle and the aqueduct.