Differences in low- and high-grade astrocytomas among various diagnostic MRI sequences that are currently utilized in astrocytoma diagnoses

Imaging modalityLow-grade astrocytomasHigh-grade astrocytomas
MRIWell-defined homogeneous masses with little or no mass effect, vasogenic edema, or enhancement after contrast administrationStrong contrast enhancement, peritumoral edema (evident on T2-FLAIR sequences), mass effects, heterogeneity, central necrosis, and intratumoral hemorrhage on conventional MRI
SWILow ITSS gradeHigh ITSS grade
DWIHigh ADCLow ADC
PWILow rCBVHigh rCBV
DCEHigh KtransLow Ktrans
MRSLow Lip-Lac/Cr, low Cho/CrHigh Lip-Lac/Cr, high Cho/Cr

SWI: susceptibility-weighted imaging; ITSS: intratumoral susceptibility score; DWI: diffusion-weighted imaging; ADC: apparent diffusion coefficient; PWI: perfusion-weighted imaging; rCBV: relative cerebral blood volume; DCE: dynamic contrast enhancement; Ktrans: volume transfer coefficient; MRS: magnetic resonance spectroscopy; Lip-Lac/Cr: lipid-lactate to creatine; Cho/Cr: choline to creatine