Large syrinx with Chiari, annual surveillance. Again seen is crowding at the foramen magnum with caudal displacement of peglike cerebellar tonsils, which measure up to 9 mm below the foramen of magnum similar to prior. The right-sided cerebellar tonsil is lower than the left. CSF flow sequence is technically degraded (related to patient motion due to claustrophobia and body habitus), however, there is significantly diminished biphasic flow dorsally at the foramen magnum. CSF spaces and flow are mildly diminished ventrally at the foramen magnum.Again seen is a spinal cord syrinx beginning at the C2 level and continuing caudally to approximately the T4 level. The syrinx cavity reaches its maximum caliber at C5-C6 where it measures 8 x 3 mm in the transverse and AP dimensions, previously 8 x 5 mm at this level. The thoracic component of the syrinx is suboptimally evaluated however there appears to be slight decrease in the thoracic component, as well, for example measuring up to 4 x 2 mm in the transverse and AP dimensions, previously 5 x 2 mm.The syrinx cavity is largely positioned in the center of the cord, though at the C2 level, there is a linear slitlike component which completely traverses the right hemicord and similar to prior.The remainder of the spinal cord is grossly unremarkable. Spinal alignment is anatomic. Vertebral body height, morphology and signal characteristics are all within normal limits. No significant spinal canal or neural foraminal stenosis is appreciated.
1. Findings consistent with known Chiari I malformation including crowding at the foramen magnum and peglike cerebellar tonsils extending approximately 9 mm below the foramen magnum. There is associated diminished CSF flow at the foramen magnum, particularly posteriorly.2. Compared to 8/22/2015, there are areas of minimal interval decrease in caliber of the cervicothoracic syrinx (axial plane) but otherwise not significantly changed in the craniocaudal extent from C2 to approximately the T4 level. 3. Note patient had difficulty tolerating the study, and the thoracic sequences are significantly motion degraded.