Table 1.

VASARI imaging features

Imaging Features	Scoring Value	Definition
Major axis	NA	The longest diameter of the tumor which is based upon measurement of the FLAIR abnormality on a single axial image that demonstrates the largest cross-sectional area.
Minor axis	NA	The diameter of the FLAIR abnormality which is perpendicular to the longest diameter. The measurement is performed on a single axial image that demonstrates the largest cross-sectional area.
Tumor location	Frontal lobe Temporal lobe Parietal lobe Occipital lobe Insular Basal ganglia Thalamus Brainstem Cerebellum Corpus callosum	Location of lesion geographic epicenter, the largest component of the tumor, either contrast-enhancing tumor (CET) or non-contrast-enhancing tumor (nCET). Nonenhancing tumor (nCET) is defined as regions of T2W hyperintensity (less than the intensity of cerebrospinal fluid, with corresponding T1W hypointensity) that are associated with mass effect and architectural distortion, including blurring of the gray-white interface.
Side of tumor epicenter	Right Center/Bilateral Left	Side of lesion epicenter irrespective of whether the lesion crosses into the contralateral hemisphere.
Eloquent brain	No eloquent brain Speech motor Speech receptive Motor Vision	Presence of tumor involvement of the eloquent cortex or immediate subcortical white matter of eloquent cortex.
Enhancement quality	No contrast enhancement Mild (when barely discernible but unequivocal degree of enhancement is present relative to precontrast images) Marked (obvious tissue enhancement).	Qualitative degree of contrast enhancement defined as having all or portions of the tumor that demonstrate significantly higher signal on the postcontrast T1W images compared with precontrast T1W images.
Proportion enhancing	<5%, 6%–33%, 34%–67%, 68%–95%, >95%	Visually estimated proportion of enhancing component to the entire tumor
Proportion nCET	<5%, 6%–33%, 34%–67%, 68%–95%, >95%	Visually estimated proportion of nonenhancing component to the entire tumor
Proportion necrosis	<5%, 6%–33%, 34%–67%, 68%–95%, >95%	Visually estimated proportion of necrosis to the entire tumor. Necrosis is defined as a region within the tumor that does not enhance, is high on T2W and proton density images, is low on T1W images, and has an irregular border.
Proportion of edema	<5%, 6%–33%, 34%–67%, 68%–95%, >95%	Visually estimated proportion of edema to the entire tumor. Edema is defined as a region which is greater in signal than nCET and somewhat lower in signal than CSF. Pseudopods are characteristic of edema.
Cyst(s)	Absent OR present	Well-defined, rounded, often eccentric regions of very bright T2W signal and low T1W signal essentially matching CSF signal intensity, with very thin, regular, smooth, nonenhancing or regularly enhancing walls, possibly with thin, regular, internal septations.
Multifocal or multicentric	Focal Multifocal or multicentric Gliomatosis	Multifocal is defined as having at least one region of tumor, either enhancing or nonenhancing, which is not contiguous with the dominant lesion and is outside the region of signal abnormality (edema) surrounding the dominant mass. This can be defined as those resulting from dissemination or growth by an established route, spread via commissural or other pathways, or via CSF channels or local metastases. Multicentric are widely separated lesions in different lobes or different hemispheres that cannot be attributed to one of the previously mentioned pathways. Gliomatosis refers to generalized neoplastic transformation of the white matter of most of a hemisphere.
T1/FLAIR ratio	Expansive (size of precontrast T1 abnormality approximates size of FLAIR abnormality) Mixed (size of T1 abnormality moderately less than FLAIR envelope) Infiltrative (size of precontrast T1 abnormality much smaller than size of FLAIR abnormality)	Gross comparison in the overall lesion size between precontrast T1 and FLAIR (in the same plane). Use T2 if FLAIR is not provided.
Thickness of enhancing margin	Thin (<3 mm) Thick/nodular (>3 mm) Solid (only solid enhancement, no rim)	The thickness of enhancing margin of the tumor. The scoring is not applicable if there is no contrast enhancement.
Definition of the enhancing margin	Well defined Poorly defined	The definition of the outside margin of the enhancement. The scoring is not applicable if there is no contrast enhancement.
Definition of the nonenhancing margin	Well defined Poorly defined	The definition of the outside margin of the nonenhancing margin of the tumor.
Hemorrhage	Yes OR No	Intrinsic hemorrhage anywhere in the tumor matrix. Any intrinsic foci of low signal on T2WI or high signal on T1WI.
Diffusion characteristics	Facilitated Restricted Mixed Indeterminate	Predominantly facilitated or restricted diffusion in the enhancing or nCET portion of the tumor. (Based on apparent diffusion coefficient [ADC] map) (Rate CET alone when present, otherwise use nCET) Indeterminate = unsure. Mixed = relatively equal proportion of facilitated and restricted. No ADC maps = use no images. Proportion of tissue not relevant.
Pial invasion	Yes OR No	Enhancement of the overlying pia in continuity with enhancing or nonenhancing tumor.
Ependymal extension	Yes OR No	Invasion of any adjacent ependymal surface in continuity with enhancing or nonenhancing tumor matrix.
Cortical involvement	Yes OR No	Nonenhancing or enhancing tumor extending to the cortical mantle or cortex is no longer distinguishable relative to subjacent tumor.
Deep white matter invasion	Yes OR No	Enhancing or nCET tumor extending into the internal capsule, corpus callosum, or brainstem.
nCET crosses midline	Yes OR No	nCET crosses into contralateral hemisphere through white matter commissures (exclusive of herniated ipsilateral tissue).
CET crosses midline	Yes OR No	Enhancing tissue crosses into contralateral hemisphere through white matter commissures (exclusive of herniated ipsilateral tissue).
Satellites	Yes OR No	An area of enhancement within the region of signal abnormality surrounding the dominant lesion but not contiguous in any part with the major tumor mass.
Calvarial remodeling	Yes OR No	Erosion of inner table of skull (possibly a secondary sign of slow growth).