Tentorial meningioma

   March 24, 2020  Posted in Central Nervous System, Tumour

Clinical:

  • A 79 years old lady
  • Presented with left-sided blurring of vision for one month
  • Associated with headache and dizziness.
  • Clinical examination shows both optic discs are pale.
  • No neurological deficit
CT scan of brain in axial plane, soft tissue window
Reformatted CT scan in coronal plane soft tissue window

CT scan findings:

  • There is extra-axial enhancing mass seen at the left posterior cerebellum
  • The mass measures about 3.1 x 2.3 cm
  • There is associated minimal perilesional oedema.
  • Presence of calcification within the mass lesion is seen.
  • There is adjacent cortical buckling with mass effect to left cerebellum.
  • No adjacent bony hyperostosis.

     

    MRI of brain in axial plane
    MRI of brain T1 post gadolinium

     

    MRI findings:

  • There is well defined avidly enhancing extraaxial mass with dural tail seen at left posterior fossae.
  • It measures 3.3×3.1×3.5cm (WxAPxCC).
  • This mass causing elevation of the left tentorium cerebellar and in close contact with the left tentorial cerebelli.
  • No filling defect of the left tranverse sinus to suggest thrombosis.

     

Diagnosis: Tentorium cerebelli meningioma (HPE proven)

Discussion:

  • Meningioma is the most common extra-axial tumour in adults
  • It is one of the most common intracranial tumours (15-20%) in adults.
  • Mainly occurs in middle-aged women.
  • Common site include: parasagittal-falcine (50%), sphenoid wing (20%), floor of the anterion cranial fossa (10%), parasellar region (10%), tentorium and cerebello-pontine angle region.
  • Histologic types: typical (90% to 95%), atypical (3-5%), and frankly malignant (1%).
  • A dural tail suggests an extra-axial mass but is probably related to reactive changes rather than tumour extension.
  • On CT scan it is sharply circumscribed smooth mass abutting dura, 70-75% are hyperdense and 25% are isodense. Calcification seen in 20-25% of cases, necrosis and hemorrhage in 8-23%. Peritumoral hypodense vasogenic oedema in 60% of cases. More than 90& shows intense homogenous enhancement.
  • On MRI,
    • typically iso to slightly hypointense with cortex on T1
    • necrosis, cyst and hemorrhage in 8-23%
    • gray matter buckling sign
    • variable ‘sunburst’ appearance on T2WI
    • hyperintense T2/FLAIr dural tail and oedema
    • GRE sequence to look for calcification (common) and hemorrhage (rare)
    • variable appearance on DWI and ADC for typical meningioma
    • Enhances homogenously and intensely on post contrast
    • dural tail sign in 35-80% of cases, non specific feature
Author: radhianahassan