Meningocele or Meningomyelocele688
IMAGINGRadiographyFindingsn Well-demarcated mass, with round or
elliptical, smooth margins.
Utilityn Abnormality often first detected on the radiographn
Radiographic findings similar to those of neurogenic tumor
CTFindingsn Continuity between cerebrospinal fluid in thecal sac
and meningocele
n Kyphoscoliosis and meningocele usually at apex of curvature on
its convex side
n Enlargement of intervertebral foramenn Associated vertebral
and rib anomalies commonUtilityn CT usually diagnostic
MRIFindingsn Continuity between cerebrospinal fluid in thecal
sac and meningocele
Utilityn Diagnostic method of choice; provides best
visualiza-tion of spinal cord, meninges, and adjacent
structures
CLINICAL PRESENTATIONn Pain and neurologic symptoms
DIFFERENTIAL DIAGNOSISn Nerve sheath tumors (neurilemoma,
neurofibroma, and malignant nerve sheath tumor)
n Sympathetic ganglia tumors (ganglioneuromas,
gan-glioneuroblastomas, and neuroblastomas)
PATHOLOGYn Meningocele and meningomyelocele are rare anoma-lies
that consist of herniation of leptomeninges through an
intervertebral foramen.
n Meningocele contains cerebrospinal fluid only, whereas
meningomyelocele also contains neural tis-sue.
n Abnormalities occur slightly more often on right side than on
the left and are situated anywhere between thoracic inlet and
diaphragm.
INCIDENCE/PREVALENCE AND EPIDEMIOLOGYn Approximately 75% of
patients present between ages of 30-60 years.
n Sixty percent to 80% of patients have neurofibromatosis.
Suggested ReadingsCabooter M, Bogaerts Y, Javaheri S, et al:
Intrathoracic meningnocele.
Eur J Respir Dis 63:347-350, 1982.Glazer HS, Siegel MJ, Sagel
SS: Low-attenuation mediastinal masses
on CT. AJR Am J Roentgenol 152:1173-1177, 1989.Rainov NG,
Heidecke V, Burkert W: Thoracic and lumbar meningo-
cele in neurofibromatosis type 1: Report of two cases and review
of the literature. Neurosurg Rev 18:127-134, 1995.
Strollo DC, Rosado-de-Christenson ML, Jett JR: Primary
mediastinal tumors: II. Tumors of the middle and posterior
mediastinum. Chest 112:1344-1357, 1997.
DEFINITION: Meningocele and meningomyelocele are rare anomalies
that consist of herniation of the leptomeninges through an
intervertebral foramen.
DIAGNOSTIC PEARLSn Continuity between the cerebrospinal fluid in
the thecal sac and the meningocele
n Enlargement of the intervertebral foramenn Meningocele:
contains cerebrospinal fluid onlyn Meningomyelocele: contains
neural tissuen Majority of patients have neurofibromatosis
WHAT THE REFERRING PHYSICIAN NEEDS TO KNOW n Association with
vertebral and rib anomalies is common and should suggest the
diagnosis. n Majority of patients have neurofibromatosis. n MRI is
the diagnostic method of choice.
