Jugular fossa meningocele
A radiograph of paranasal sinuses and a lateral view of the skull did
not reveal any significant abnormality. The patient was referred for a
magnetic resonance imaging (MRI) scan of the brain. The scan was
performed on a 1.5T MR scanner. A bony defect was observed in the right
jugular fossa. Adjacent bones were well scalloped. No obvious
destruction of the cortical bone was suspected. There was continuation
of the dural meningeal pouch within this defect. It was lining the CSF
collection, which appeared hyper-intense on T2-weighted images, and
hypo-intense on T1-weighted images. No obvious herniation of the
neuroparenchyme or cranial nerve was seen within this out-pouching
Imaging findings suggested meningocele in the right
jugular foramen region. The contents of the right jugular foramen were
displaced laterally to this meningocele. It was also extending minimally
anteriorly towards the foramen lacerum. Inferiorly, it was bulging into
the right parapharyngeal space. The medial margin was seen near the
pharyngeal wall. The carotid vessels were also displaced laterally. The
right parapharyngeal fat was reduced, compared to that of the left side.
The patient was informed about this type of congenital anomaly; she
decided not to undergo surgical intervention. She is being treated
symptomatically with analgesics.
Cephaloceles are congenital herniations of intracranial contents into
the skull’s bony defects. These may be meningocele or
meningo-encephaloceles (abbreviated as encephalocele), depending on the
absence or presence of brain tissue.1 When the lepto-meninges
and CSF are herniated without associated herniation of brain
parenchyma, it is termed meningocele. Meningoceles of the jugular
foramen region are extremely uncommon and difficult to explain by
current skull-base cephalocele classifications.
foramen is situated between the petrous portion of temporal and
occipital bones and originates from persistence of the embryologic
foramen lacerumposticus, the space between the basi-occiput and auditory
canal.2 The cephaloceles are known to occur through the suture lines or junction of several bones.3
The skull base cephaloceles are classified into fronto-ethmoidal,
spheno-orbital, sphenomaxillary, temporal, and nasopharyngeal types.3,4
Rare case reports of cephaloceles through the tegmen of petrous
temporal bone, the greater wing of the sphenoid and the centre of the
basilar occipital bones have been described.3,5,6 Our case,
with its involvement of the jugular fossa, does not fit precisely within
this classification. However, another case of large skull-base
meningo-encephalocele in a newborn has been described with a neck mass
passing through the jugular foramen.7
Basal cephaloceles are rare, with an incidence of about 1 in 35,000 births.7
Basal cephaloceles are commonly occult and without any symptoms.
Therefore, they may not be identified until adulthood, especially if
there is no herniation of brain contents, as in our case. The prognosis
is better, especially when they are < 5 cm in diameter, do not
contain dysplastic or brain tissue, and when they are not associated
with hydrocephalus or other anomalies.8 Our patient, who had
presented in adulthood, thus had a better prognosis. Cephaloceles are
commonly associated with malformation syndromes (neurofibromatosis,
Dandy Walker syndrome, septo-optic dysplasia, etc.), heterotopias, cleft
palate, other midline anomalies, craniostenosis, agenesis of the corpus
callosum, brainstem anomalies, etc.1,7 Their complications
include CSF leak and fistula formation, local mass effect on adjacent
structures near the skull base, and increased risk of CSF infection,
Jugular fossa meningoceles may not fit exactly into skull base
cephalocele classifications. Meningoceles involving the jugular fossa
can present in adulthood and can have better prognosis, especially if
they are smaller and not associated with hydrocephalus or other
brain/skull anomalies. Possible CSF leak and mass effect at the skull
base are important complications.
- Matuchansky C, Colin R, et al. Cavitation of mesenteric lymph nodes, splenic atrophy, and a flat small intestinal mucosa. Gastoenterology. 1984;87:606-614.
- Howat A, McPhie J, et al. Cavitation of mesenteric lymph nodes: A
rare complication of celiac disease, associated with a poor outcome. Histopathology.1995;27:349-354.
- Holmes G. Mesenteric lymph node cavitation in coeliac disease. Gut. 1986;27:728-733.