Gangliogliomas are uncommon CNS tumours which account for around 2% (from 0.4-3.8%) of all primary intracranial tumours; and up to 10% of primary cerebral tumours in children. They are, however, the most frequent of the neuronal-glial CNS neoplasms 6.
They are of low grade (WHO Grade I or II). Typical occurrence is in the temporal lobes, although they have been described in all parts of the central nervous system.
Radio graphic features
Imaging findings mirror the various patterns of growth which these tumours may demonstrate, and unfortunately their appearance is very variable. Partially cystic mass with an enhancing mural nodule is seen in 35-55% of cases. They may also simply present as a solid mass expanding the overlying gyrus. An infiltrating mass is uncommon and may reflect higher grade.
CT
Findings are of a mass which is often non specific. General features include:
iso- or hypodense
frequently calcified ~35%
bony remodeling or thinning can indicate the slow growing nature of the tumour
enhancement is seen in approximately 50% of cases (involving the solid non-calcified component)
MRI
Reported signal characteristics include:
T1: iso to hypo intense
C+ (Gd): variable contrast enhancement
T2: hyperintense solid component, with variable signal in the cystic component depending on amount of proteinaceous material or presence of blood products; peritumoral FLAIR/T2 oedema is distinctly uncommon
GE/SWI: calcified areas will show blooming
They are of low grade (WHO Grade I or II). Typical occurrence is in the temporal lobes, although they have been described in all parts of the central nervous system.
Radio graphic features
Imaging findings mirror the various patterns of growth which these tumours may demonstrate, and unfortunately their appearance is very variable. Partially cystic mass with an enhancing mural nodule is seen in 35-55% of cases. They may also simply present as a solid mass expanding the overlying gyrus. An infiltrating mass is uncommon and may reflect higher grade.
CT
Findings are of a mass which is often non specific. General features include:
iso- or hypodense
frequently calcified ~35%
bony remodeling or thinning can indicate the slow growing nature of the tumour
enhancement is seen in approximately 50% of cases (involving the solid non-calcified component)
MRI
Reported signal characteristics include:
T1: iso to hypo intense
C+ (Gd): variable contrast enhancement
T2: hyperintense solid component, with variable signal in the cystic component depending on amount of proteinaceous material or presence of blood products; peritumoral FLAIR/T2 oedema is distinctly uncommon
GE/SWI: calcified areas will show blooming
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