Brain Stem Gliomas MRI: Difference between revisions
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'''Diffuse brainstem gliomas''' | '''Diffuse brainstem gliomas''' | ||
The pons is enlarged, with the basilar artery displaced anteriorly against the clivus and potentially engulfed. The floor of the fourth ventricle is flattened ("flat floor of fourth ventricle sign") and [[obstructive hydrocephalus]] may be present. Occasionally the tumor is exophytic, either outwards into the basal cisterns or centrally in the 4th ventricle. Usually the tumor is homogenous pre-treatment, however in a minority of patients areas of [[necrosis]] may be present. | The pons is enlarged, with the basilar artery displaced anteriorly against the clivus and potentially engulfed. The floor of the fourth ventricle is flattened ("flat floor of fourth ventricle sign") and [[obstructive hydrocephalus]] may be present. Occasionally the tumor is exophytic, either outwards into the basal cisterns or centrally in the 4th ventricle. Usually the tumor is homogenous pre-treatment, however in a minority of patients areas of [[necrosis]] may be present. | ||
:*'''T1''': Decreased intensity | :*'''T1''': Decreased intensity | ||
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'''Tectal glioma''' | '''Tectal glioma''' | ||
Typically the tumors demonstrate expansion of the tectal plate by a solid nodule of tissue. | Typically the tumors demonstrate expansion of the tectal plate by a solid nodule of tissue. | ||
:*'''T1''': Iso to slightly hypointense to grey matter 1-3 | :*'''T1''': Iso to slightly hypointense to grey matter 1-3 |
Revision as of 18:35, 28 August 2015
Brain Stem Gliomas Microchapters |
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Brain Stem Gliomas MRI On the Web |
American Roentgen Ray Society Images of Brain Stem Gliomas MRI |
Risk calculators and risk factors for Brain Stem Gliomas MRI |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]Associate Editor(s)-in-Chief: Sujit Routray, M.D. [2]
Overview
MRI
MRI is the imaging modality of choice for brainstem gliomas. The findings will vary with the tumor type.[1]
Diffuse brainstem gliomas
The pons is enlarged, with the basilar artery displaced anteriorly against the clivus and potentially engulfed. The floor of the fourth ventricle is flattened ("flat floor of fourth ventricle sign") and obstructive hydrocephalus may be present. Occasionally the tumor is exophytic, either outwards into the basal cisterns or centrally in the 4th ventricle. Usually the tumor is homogenous pre-treatment, however in a minority of patients areas of necrosis may be present.
- T1: Decreased intensity
- T2: Heterogeneously increased
- T1 C+ (Gd): Usually minimal (can enhance post radiotherapy)
- Diffusion weighted imaging (DWI): Usually normal, occasionally mildly restricted
Tectal glioma
Typically the tumors demonstrate expansion of the tectal plate by a solid nodule of tissue.
- T1: Iso to slightly hypointense to grey matter 1-3
- T2: Hyperintense to grey matter
- T1 C+ (Gd): usually no enhancement
With time the mass can develop small cystic spaces (sometimes associated with neurological deficits) or calcification. Higher grade tumors tend to be larger and tend to enhance more vividly.
References
- ↑ Imaging of Brainstem gliomas. Dr Yuranga Weerakkody and Dr Frank Gaillard et al. Radiopaedia 2015. http://radiopaedia.org/articles/brainstem-glioma