Cerebral Fiber Changes in Patients with Hereditary Spastic Paraparesis Assessed by Diffusion Tensor MRI

Hereditary spastic paraparesis (HSP) comprises a heterogeneous group of congenital diseases with progressive spastic paresis of the legs. Most common are pure forms with autosomal dominant inheritance (HSP4 and HSP3). Pathological findings revealed degeneration and demyelinization of the corticospinal tract increasing from the cervical to the lumbal level of the medulla considering a dying-back axonopathy of these long axons. However, occasional extraspinal involvement like thin corpus callosum, cerebellar atrophy, and cognitive impairment in HSP4 suggests other factors for neural degeneration beside axon length…