Cerebrotendinous xanthomatosis: The spectrum of imaging findings and the correlation with neuropathologic findings

PURPOSE: To describe imaging findings and their neuropathologic correlate i n patients with cerebrotendinous xanthomatosis (CTX). MATERIALS AND METHODS: Computed tomographic (CT) and magnetic resonance (MR ) images in 24 patients with symptoms (mean age at time of imaging, 37 year s; mean disease duration, 18 years) were reviewed for site and frequency of brain, spinal cord, and Achilles tendon involvement. Two patients died, an d imaging findings were compared with postmortem neuropathologic findings. RESULTS: Apart from nonspecific supratentorial atrophy and deep white matte r changes, more typical hyperintense lesions were seen on T2-weighted image s in the dentate nucleus (in 79% of patients), globus pallidus, substantia nigra, and inferior olive and extended into adjacent white matter as diseas e progressed. In these locations, lipid crystal clefts and perivascular mac rophages, neuronal loss, demyelination, fibrosis, and reactive astrocytosis were found at microscopic examination. Hypointensity was sometimes found o n T2-weighted images in the dentate nucleus and was related to deposition o f hemosiderin and calcifications. CT depicted fewer lesions; all had low at tenuation, except for the calcifications. Spinal cord MR imaging revealed i ncreased signal intensity in the lateral and dorsal columns on T2-weighted images. Achilles tendon xanthomas displayed intermediate signal intensity o n T1- and T2-weighted images. CONCLUSION: The typical pattern of MR imaging findings reflects the classic histopathologic findings and should prompt the diagnosis of CTX.