Learning objectives
-Illustrate the medulloblastoma lesions findings on MRI and differential diagnoses on the MRI in the 15 years of experience of the Neuroradiology service of the Hospital of Clínicas of Porto Alegre - Rio Grande do Sul - Brazil.
-Describe the most common and uncommon findings on CT and on MRI of medulloblastoma in the series of cases ( T1,
T2,
FLAIR,
DWI/ADC,
MRI spectroscopy ).
-Discuss the CT and MRI findings differential diagnosis in the case series of medulloblastoma lesions ( T1,
T2,
FLAIR,
DWI/ADC,...
Background
We report the magnetic resonance imaging findings of a series of cases from the experience of patients diagnosed with medulloblastoma in the 15 years experience of the Neuroradiology service at Hospital de Clínicas,
Porto Alegre,
RS,
Brazil.
The peak of occurrence is between 5-7 years of age,
with 70% of them occurring under 16 years.Neuroimaging studies play an important role in the diagnosis and staging of medulloblastoma,
in assessing the degree of resection,
follow-up,
and recurrence.
Magnetic resonance imaging (MRI) is more sensitive in the...
Findings and procedure details
The most common location of medulloblastoma is a dense,
round mass in the fourth ventricle.MB subgroups arise in distinct regions of cerebellum,associated with subgroup-specific genetic aberrations
and cells of origin :
Midline (4th ventricle) : predominantly (but not exclusively) groups 3 and 4
Cerebellar/peduncle /cerebellopontine angle cistern: WNT most common
Cerebellar hemispheres (lateral):SHH (slightly > 50%,
remainder mostly midline).
Imaging findings on non-contrast tomography:
Solid mass in the 4th ventricle : 90% hyperdense,
Ca ++ in up to 20%,
rare hemorrhage,
small intratumoral cysts /...
Conclusion
Medulloblastoma is rare brain tumor there are few studies that describe the atypical characteristics and key imaging findings of this tumor.
Radiologists play a central role in the diagnosis of major CNS.
In this experiment,
it was observed that magnetic MRI played an important role in the elucidation of differential diagnoses because it had sensitivity in the specific characterization of each lesion.
It is concluded that in some cases,
correlation with clinical data and biopsy is necessary for the final diagnosis.
Personal information
Thaylla Maybe Bedinot Da Conceição,MD,
Department of Radiology,
Hospital de Clínicas de Porto Alegre
E-mail:
[email protected]
Radiology Division.
Hospital de Clínicas de Porto Alegre,
Porto Alegre,
Rio Grande do Sul,
Brazil.
BRAIN - Basic Research and Advanced Investigations in Neurology – Division of Neurology,
Hospital de Clínicas de Porto Alegre,
Porto Alegre,
Rio Grande do Sul,
Brazil.
PPGCM: Graduate Program in Medical Science.
Hospital de Clínicas de Porto Alegre,
Porto Alegre,
Rio Grande do Sul,
Brazil.
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