Imaging features in conventional MRI, spectroscopy and diffusion weighted images of hereditary diffuse leukoencephalopathy with axonal spheroids (HDLS).

[cadasil]

Hereditary diffuse leukoencephalopathy with axonal spheroids (HDLS ) is a rare autosomal dominant disease caused by mutations within the colony stimulating factor 1 receptor (CSF 1 R ) gene . While a small number of reports on imaging findings in routine MRI exist , reported imaging findings in DWI and spectroscopy are scarce , and limited to not genetically proven case reports . We assessed MRI including DWI and MR spectroscopy in six patients with HDLS and two asymptomatic mutation carriers . A total of 13 MRIs were evaluated and a score of the white -matter lesion (WML ) load was calculated . The course of MR abnormalities was followed for 6 -19 months in four patients and 95 months in one carrier . MRI revealed widespread white -matter lesions of patchy or confluent pattern especially in the frontal and occipital lobe . The pyramidal tract was less affected than the surrounding tissue in all symptomatic patients on conventional T 2 WI . Three of four cases with DWI showed small dots of diffusion restriction within WML . Spectroscopy showed increased levels of mIns , Cho and lactate while NAA was decreased . Asymptomatic mutation carriers had , for the age of the patients , unusually pronounced unspecific WMLs . No diffusion restriction or alterations in metabolite levels could be detected in asymptomatic mutation carriers . Microbleeds were not found in any patient . Diffusion restriction seems to be a typical imaging pattern visible in patients with active disease progression in HDLS . Spectroscopic findings and the absence of microbleeds differ clearly from reported findings in CADASIL and subcortical arteriosclerotic encephalopathy . While the distribution and character of WMLs in asymptomatic cases remain unspecific they are likely to represent subclinical markers of HDLS .