 Alignment is normal. The marrow signal is benign. Redemonstrated is an elongated peglike configuration of cerebellar tonsils with abnormal craniocaudal extent of about 2.5 cm below the level of the foramen magnum to the C2/3 intervertebral level. CSF flow analysis demonstrates diminished, yet persistent flow posteriorly at the level of the cervical tonsils. Additionally, there is diminished CSF flow anteriorly due to mass effect from the combined cord and descended tonsils.Just inferior to the level of the tonsillar ectopia, T2 signal is noted within the cord parenchyma from C3 through the C5 levels which is ill-defined and nonenhancing. The cord and conus are otherwise normal in signal. The conus terminates at the L1/2 level and is normal in morphology. There are no findings of fatty filum.There are no osseous dysplasias or stenoses.
1.Redemonstrated is an elongated peglike configuration of cerebellar tonsils with abnormal craniocaudal extent of about 2.5 cm below the level of the foramen magnum to the C2/3 intervertebral level consistent with Chiari I information.2.Just inferior to the level of the tonsillar ectopia, T2 signal is noted within the cord parenchyma from C3 through the C5 levels which is ill-defined and nonenhancing. This most likely represents a pre-syrinx state.