Clinical question: Post op Chiari malformation decompression, meningitis, 4 months follow evaluate for change. Signs and symptoms: Headache, fever and neck pain. Nonenhanced cervical spine MRI:Negative diffusion weighted images.Examination is to status post suboccipital midline craniectomy for Chiari decompression. Compared to prior exam there is significant reduction in size of a pseudomeningocele/seroma posterior to the craniectomy site. The remaining epidural fluid collection at the site measures approximately 8 mm in thickness and 24-mm in AP axis measured on sagittal T2 weighted cervical spine MRI exam.There is posterior tenting of the cervical medullary junction of the cord at the surgical site and without visible subarachnoid space inferior to cerebellar and vermis. Although the findings may be within expected postop changes possibility of adhesion cannot be entirely excluded.There is no detectable signal abnormality of adjacent brain parenchyma on any of the MRI sequences.The cortical sulci, ventricular system, CSF spaces and myelination of brain is within normal on all MRI sequences.Unenhanced cervical MRI:Examination demonstrate significant improvement in postoperative changes of suboccipital Chiari decompression as detailed above.There is normal signal intensity and caliber of the cervical and uppermost visualized thoracic cord and without evidence of syrinx.Fiesta 3-D images demonstrate a normal appearing aqueduct and quadrigeminal plate.CSF flow study demonstrate presence of biphasic flow through the neo-foramen magnum anteriorly however without detectable probe posteriorly. There is also no detectable flow through the fourth ventricle or the aqueduct.There is normal signal intensity and alignment of vertebral column.
1.Nonenhanced brain MRI demonstrate improvement of postoperative changes of Chiari decompression with significant decreased size of pseudomeningocele/seroma at the surgical site since prior study. Unremarkable nonenhanced brain MRI otherwise. Please see above comments.2.MRI of the cervical spine demonstrate improved post operative changes of Chiari decompression. No evidence of syrinx of the cervical or uppermost visualized thoracic cord.3.CSF flow study demonstrate presence of biphasic flow anteriorly through neo-foramen magnum and without detectable flow posteriorly. There is also no detectable flow through the fourth ventricle or the aqueduct .