Differentiation between Nonenhancing Tumor in Glioblastoma and Vasogenic Edema Using Diffusion-Weighted and Dynamic...

Area of Science:

• Neuroimaging
• Radiology
• Oncology

Background:

• Differentiating nonenhancing glioblastoma from vasogenic edema is a significant challenge in neuroimaging.
• Accurate distinction is crucial for effective treatment planning and patient management.

Purpose of the Study:

• To evaluate the utility of diffusion-weighted imaging (DWI) and dynamic susceptibility contrast (DSC) MRI, specifically apparent diffusion coefficient (ADC) and relative cerebral blood volume (rCBV) values.
• To distinguish between nonenhancing glioblastoma and vasogenic edema using these quantitative MRI parameters.

Main Methods:

• Retrospective analysis of 111 patients with glioblastoma and available pretreatment MRIs.
• Comparison of ADC and rCBV values between solid nonenhancing glioblastomas, perilesional nonenhancing T2-FLAIR hyperintensity, and vasogenic edema.
• Receiver operating characteristic (ROC) analysis to determine optimal thresholds for classification.

Main Results:

• Solid nonenhancing glioblastomas showed significantly lower ADC and higher rCBV compared to vasogenic edema (P < .001).
• Optimal ADC and rCBV thresholds achieved excellent sensitivity and specificity for differentiating solid nonenhancing glioblastoma from vasogenic edema.
• Perilesional nonenhancing T2-FLAIR hyperintensity had ADC values similar to vasogenic edema but significantly higher rCBV (P = .03).

Conclusions:

• Diffusion- and perfusion-weighted MRI parameters (ADC and rCBV) are valuable biomarkers for differentiating nonenhancing glioblastoma from vasogenic edema.
• Identified threshold values can enhance glioblastoma characterization and preoperative differentiation from metastases.
• These findings support more precise, image-guided clinical management of brain tumors.