White and grey matter abnormalities in patients with SPG11 mutations.
BACKGROUND
Mutations in SPG11 are the most frequent known cause of autosomal recessive hereditary spastic paraplegia. Corpus callosum thinning is a hallmark of the condition but little is known about damage to other structures in the CNS.


OBJECTIVE
To evaluate in vivo cerebral damage in patients with SPG11 mutations.


METHODS
5 patients and 15 age and sex matched healthy controls underwent high resolution diffusion tensor imaging (32 directions) and a T1 volumetric (1 mm slices) acquisition protocol in a 3 T scanner (Philips Achieva). These sequences were then analysed through voxel based morphometry (VBM) and tract based spatial statistics (TBSS).


RESULTS
Mean age of the patients was 23.6±4.5 years (range 14-45) and mean duration of disease was 12 years (range 5-15). All patients presented with progressive spastic paraplegia and three were already wheelchair bound when first evaluated. Mutations found were: c.529_533delATATT, c.704_705delAT, c.733_734delAT, c.118C>T and c.7256A>G. VBM identified significant grey matter atrophy in both the thalamus and lentiform nuclei. TBSS analyses revealed reduced fractional anisotropy involving symmetrically subcortical white matter of the temporal and frontal lobes, the cingulated gyrus, cuneus, striatum, corpus callosum and brainstem.


CONCLUSIONS
Widespread white matter damage in patients with SPG11 mutations has been demonstrated. Grey matter atrophy was prominent in both the thalamus and basal ganglia but not in the cerebral cortex. These findings suggest that neuronal damage/dysfunction is more widespread than previously recognised in this condition.
Department of Neurology and Neuroimaging Laboratory, Faculty of Medicine, University of Campinase UNICAMP, Campinas, São Paulo, Brazil.
Marcondes C
MC
França
Clarissa L
CL
Yasuda
Fabrício R S
FR
Pereira
Anelyssa
A
D'Abreu
Camila M
CM
Lopes-Ramos
Madalena V
MV
Rosa
Fernando
F
Cendes
Iscia
I
Lopes-Cendes
D000293:Adolescent; D000328:Adult; D001921:Brain / Q000473:pathology* / Q000503:physiopathology; D003337:Corpus Callosum / Q000473:pathology; D003342:Corpus Striatum / Q000473:pathology; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011506:Proteins / Q000235:genetics*; D015419:Spastic Paraplegia, Hereditary / Q000235:genetics / Q000473:pathology*; D013788:Thalamus / Q000473:pathology; D055815:Young Adult
D011506:Proteins; C520412:SPG11 protein, human