Type:
Educational Exhibit
Keywords:
Education and training, Developmental disease, Education, MR, Neuroradiology brain, CNS
Authors:
O. Bronov, O. Karpov, A. Marinets, V. Kitaev; Moscow/RU
DOI:
10.26044/ecr2019/C-3044
Background
Encephaloceles are characterised by defects of the bony skull through which herniation of the intracranial contents can occur.
Encephaloceles are classified according to their location and contents.
Those containing only cerebrospinal fluid (CSF) and meninges are termed craniomeningoceles; if the lesion also contains neural tissue then it is termed a meningoencephalocele. Encephaloceles of the skull base account for 25% of all encephaloceles and can be categorized according to their anatomical location: fronto-ethmoidal,
spheno-orbital,
spheno-maxillary, nasopharyngeal,
and aural.
An encephalocele can also be acquired as a result of inflammatory or neoplastic processes or as a consequence of trauma or surgery.
Encephalocele-related seizures have been reported in the literature.
Meningoencephaloceles can be associated with microscopic congenital malformations.
As such,
it is important to realize that the meningoencephalocele may be the “the tip of the iceberg” and the diagnosis should lead one to carefully search for evidence of an underlying malformation of cortical development.
However,
seizure rates and associated cortical congenital abnormalities are probably more uncommon in this rare form of encephaloceles compared to non-skull base encephaloceles (cranial-vault) seen in pediatric patients,
which commonly have multifocal cortical abnormalities and generalized epilepsy
The imperative for surgical treatment is usually strong, given the potential for recurrent meningitis,
brain damage from herniation and refractory seizures.
The surgical approach and technique is dependent upon the position and size of both the defect and the encephalocele.
Imaging is often reported to be normal,
with the skull-base lesion noted only upon reassessment of initial neuroimaging.
The use of 3T MR imaging and high resolution 3D sequences correlated with improved detection of encephalocele.
Detection of small encephaloceles expedited by reviewing the axial,
sagittal and curvilinear reconstructions of 3D sequences.