====== Brain tumor protocol ======

[[MRI]] [[protocol]] for [[brain tumor]] assessment is a group of MRI [[sequence]]s put together to best approach [[CNS]] [[tumor]]s in general.



===== Sequences =====

A good protocol for this purpose involves at least:

[[T1]] weighted

plane: [[axial]] and [[sagittal]] (or volumetric 3D)

[[sequence]]: [[fast spin echo]] (T1 FSE) or gradient (T1 MPRAGE)

purpose: anatomical overview, which includes the soft tissues below the base of the skull
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[[T2]] weighted

plane: axial

sequence: T2 FSE

purpose: evaluation of basal cisterns, ventricular system, and subdural spaces, evaluation of vasogenic edema, and good visualization of flow voids in vessels
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[[FLAIR]]

plane: axial

sequence: FLAIR

purpose: assessment of white-matter tumor involvement and related vasogenic edema
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[[Diffusion-weighted imaging]] (DWI)

plane: axial

sequence: DWI: B=0, B=1000 and ADC 

purpose: evaluation of the tumor cellularity 
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Postcontrast sequences

plane: axial and coronal (at least two different planes or volumetric 3D)

sequence: post-contrast fast-spin echo (T1 FSE) or gradient (T1 MPRAGE). A fat-saturated sequence is considered in at least one plane, especially when the tumor involves the skull's base

[[Gadolinium]]-based contrast agents (GBCAs) for CNS 

gadoterate meglumine (Dotarem®)

gadobutrol (Gadavist®)

gadopentetate dimeglumine (Magnevist®)

gadobenate dimeglumine (MultiHance®)

gadodiamide (Omniscan®)

gadoversetamide (OptiMARK®)

gadoteridol (ProHance®)

all these GBCAs are approved by FDA at identical administered total doses of 0.1mmol/kg body weight 

[[susceptibility weighted imaging]] (SWI)

plane: axial

sequence: susceptibility weighted imaging (ideal) or T2

purpose: identify blood products or calcification within the tumor
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When assessing gliomas it is relevant to include advanced MRI sequences, such as:

perfusion

sequence: MR perfusion

purpose: elevation in [[rCBV]] is generally related to a high-grade tumor. It also helps in the evaluation of pseudoprogression and pseudoresponse
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spectroscopy

sequence: single or multivoxel spectroscopy

purpose: metabolic peaks characterization