Keywords:
CNS, Neuroradiology brain, CT, MR, Education, Cerebrospinal fluid
Authors:
T. V. P. Morais1, C. T. F. Perry da Câmara1, C. Pinheiro1, M. C. Diogo2, C. Conceição1; 1Lisbon/PT, 2Vienna/AT
DOI:
10.1594/ecr2018/C-1499
Results
The cases presented in the figures display include non-pathologic PVS,
usually visualized in MRI as small,
round images with intensity similar to liquor,
that do not enhance with contrast material with the surrounding brain parenchyma generally showing normal signal intensity.
Occasionally,
PVS appear markedly enlarged,
cause mass effect,
and assume bizarre cystic configurations that may be misinterpreted as other pathologic processes.
The genetic/metabolic diseases are a important cause of pathologic PVS in the pediatric population,
and in this cases the clinical/imaging correlation is essential.
The mucopolysaccharidoses are genetic disorders of metabolism characterized by enzyme deficiency,
which results in the accumulation of toxic intracellular substrate.
One example is Hurler syndrome.
Typically,
the PVS are dilated by accumulated GAG,
which results in a cribriform appearance of the white matter,
corpus callosum,
and basal ganglia.
However,
the surrounding white matter may show increased signal intensity,
representing gliosis or de- or dysmyelination,
differentiating them from normal PVS.
Hypomelanosis of Ito is a genetic disorder where patients present with characteristic skin abnormalities and may have involvement of multiple organ systems Dilatation of perivascular spaces with surrounding gliosis may be present.
Other features include cortical dyplasias,
hemimegalencephaly,
and polymicrogyria.
Other differential diagnosis are cystic tumors,
including DNET and ganglioglioma,
which often have solid components,
may enhance with contrast material,
mostly show surrounding edema,
and have contents that usually are not equal to CSF; and infections as neurocysticercosis (in the initial stage,
a cystic lesion isointense to CSF is seen,
resembling an enlarged PVS,
however,
a discrete eccentric scolex may be seen,
helping in the differential diagnosis) and cryptococcosis (on FLAIR images they are also hyperintense,
making it possible to differentiate them from normal PVS).
96 Normal 0 21 false false false PT X-NONE X-NONE