Chiari malformation, status post decompression. Syrinx and developmental delay. Brain MRI:There is no abnormal diffusion restriction. A few prominent perivascular spaces are again noted in the brain. No abnormal signal to suggest a developmental abnormality is evident in the supratentorial brain. Stable postoperative changes of suboccipital craniectomy and removal of the posterior arch of C1 with resultant expanded CSF space at the foramen magnum. The cerebellar tonsils have a rounded/uncrowded morphology. Stable mild platybasia, dorsi flexion and invagination of the dens. The ventricles are stable in size with normal configuration.CSF flow study:There is good, stable to slightly improved, biphasic flow demonstrated anterior and posterior to the upper cervical cord. At the foramen magnum, flow remains attenuated anteriorly and barely detectable posteriorly. Cervical spine MRI:Examination demonstrates further interval decreased size of cervical syrinx with resultant decreased caliber of cervical cord. The largest AP axis of the most expanded component of cervical syrinx is at C6-7 measuring 2.8 mm compared to prior study at this level of 8.7 mm.The vertebral body heights and alignments are maintained. No suspicious bone marrow signal abnormality is identified in the cervical spine. Intervertebral discs demonstrate normal height and signal. No significant spinal canal or neural foraminal narrowing is evident.Thoracic spine MRI:There has again been significant interval decreased size of the thoracic syrinx. The largest AP axis of syrinx in the upper thoracic spinal cord measures approximately 2 mm compared to prior study measurement of 5.6 mm. The syrinx does still extending to the level of the T10 vertebral body. The vertebral body heights and alignments are maintained. No suspicious bone marrow signal abnormality is identified in the thoracic spine. Intervertebral discs demonstrate normal height and signal. No significant spinal canal or neural foraminal narrowing is evident.
1.Postoperative changes related to Chiari decompression surgery are redemonstrated. Decompressed posterior fossa contents with stable to slight interval improvement in CSF flow along the upper cord, and stable attenuated flow through the foramen magnum. 2. Significantly decreased syrinx caliber in both the cervical and thoracic regions. 