ADC-Based Stratification of Molecular Glioma Subtypes Using High b-Value Diffusion-Weighted Imaging

Area of Science:

• Neuroimaging
• Oncology
• Radiology

Background:

• Gliomas are primary brain tumors with distinct molecular subtypes.
• Accurate molecular subtyping is crucial for prognosis and treatment planning.
• Current methods for molecular subtyping can be invasive or time-consuming.

Purpose of the Study:

• To evaluate the diagnostic performance of in vivo apparent diffusion coefficient (ADC) measurements for stratifying integrated molecular glioma grades.
• To compare the efficacy of different b-values in diffusion-weighted imaging (DWI) for glioma subtyping.

Main Methods:

• Retrospective analysis of 97 patients with histopathologically confirmed gliomas.
• Pre-interventional MRI with diffusion-weighted imaging (DWI) at high b-values (up to 2500 s/mm²).
• Generation of ADC, Mean Kurtosis (MK), and Mean Diffusivity (MD) maps; statistical comparison of values between molecular subgroups (IDH-mutant, IDH-wildtype, 1p/19q-codeleted) using ANOVA and ROC analysis.

Main Results:

• Two b-value-dependent ADC evaluations showed statistically significant differences between the three molecular glioma subgroups (p < 0.001).
• ADC values varied significantly across different molecular glioma classifications.

Conclusions:

• High b-value ADC derived from preoperative DWI can stratify integrated molecular glioma subgroups.
• This approach may offer a time-saving alternative to diffusion kurtosis imaging.
• Utilizing higher b-values (up to 2500 s/mm²) enhances diagnostic accuracy compared to standard DWI protocols.