MR imaging findings in autosomal recessive hereditary spastic paraplegia

Abstract

Background and purpose: Hereditary spastic paraplegia (HSP) is a disorder characterized by degeneration of the corticospinal tracts and posterior column of the spinal cord. Previously described radiologic findings included nonspecific brain abnormalities such as brain atrophy and white matter lesions, as well as atrophy of the spinal cord. In our study, we aimed to better characterize brain and spine MR imaging findings in a series of patients with HSP.

Materials and methods: Nine patients from 4 different Lebanese families with the autosomal recessive form of HSP were included in the study. All patients underwent brain and whole-spine MR imaging. We assessed the presence of white matter abnormalities mainly along the corticospinal tracts, brain atrophy, thinning of the corpus callosum, and the presence of spinal cord atrophy or abnormal signal intensity.

Results: Imaging revealed mild brain atrophy (44%), atrophy of the corpus callosum (55%), white matter lesions (67%), abnormal T2 high signal intensity in the posterior limb of the internal capsule (55%), and mild spinal cord atrophy (33%).

Conclusions: The MR imaging findings of HSP are nonspecific and variable; however, the most prominent features include atrophy of the corpus callosum, T2 signal intensity in the posterior limb of the internal capsule, and spinal cord atrophy.

Fig 1.

Axial FLAIR (A) and sagittal T1-weighted images (B) of patient 1. A, Note T2 high signal intensity in the periventricular white matter and corona radiata. B, This patient also has a very thin corpus callosum as shown on the sagittal image.

Fig 2.

Axial and coronal FLAIR images of patient 4 show high signal intensity in the posterior limb of both internal capsules (white arrows, A) and along the corticospinal tracts (white arrowheads, B).

Fig 3.

Sagittal and axial T2-weighted images of the cervical spinal cord of patient 5. There is a linear T2 hyperintense signal intensity in the posterior aspect of the spinal cord (white arrows, A), which represents, on the axial image (white arrow, B), an enlarged and posteriorly displaced ependymal canal.