 Similar to prior outside study, again seen is caudal descent of the cerebellar tonsils to the mid to lower C2 level, measuring approximately 19 mm below the foramen magnum. Cervical tonsils are peglike in configuration. There is associated crowding at the foramen magnum and C1-C2 levels. Biphasic CSF flow is mildly diminished ventrally at the foramen magnum and diminished to a greater degree posteriorly. There are ill-defined T2 hyperintensity in the cervical cord at the C2 level, which was present previously, without discrete syrinx.The cervical spine is in normal alignment. The vertebral body and disk heights are well-maintained. No worrisome focal marrow signal abnormality is appreciated.There is no significant disk bulge, herniation, spinal canal or foraminal stenosis within the cervical spine. THORACIC SPINE
1. Findings consistent with Chiari I malformation with caudal descent of the cerebellar tonsils measuring up to 19 mm below the foramen magnum. There is associated crowding and diminished biphasic CSF flow at the foramen magnum and C1-C2 levels, particularly posteriorly.2. Ill-defined T2 hyperintensity in the cervical cord at the C2 level is compatible with a "pre-syrinx" and was also present on prior outside study. There is a small syrinx at the T11 level.3. No evidence of tethered cord.