3D-ASL and TDD-MRI for True Progression and Pseudoprogression After Glioma Surgery

Background: Differentiating true progression (TP) from pseudoprogression (PsP) after glioma surgery remains a major clinical challenge because conventional magnetic resonance imaging (MRI) often cannot reliably distinguish these conditions. Objective: This prospective observational diagnostic accuracy study aims to evaluate the value of multiparametric imaging based on three-dimensional arterial spin labeling (3D-ASL) combined with time-dependent diffusion MRI (TDD-MRI) for differentiating TP from PsP in postoperative glioma patients. Methods: Consecutive adult patients with suspected tumor progression after glioma surgery will undergo routine MRI, 3D-ASL, and TDD-MRI examinations. Quantitative perfusion and diffusion parameters will be extracted, and a combined imaging model will be developed and evaluated. Final diagnosis will be established according to pathological findings when available or by longitudinal clinical and imaging follow-up based on the Response Assessment in Neuro-Oncology (RANO) criteria. Expected Outcomes: The primary outcome is the diagnostic performance of the combined imaging model, assessed by the area under the receiver operating characteristic curve (AUC). The study is expected to provide a noninvasive imaging strategy for distinguishing TP from PsP and to support clinical decision-making during postoperative follow-up.

Sex

All

Minimum age

18 Years

Inclusion Criteria:

* Age 18 years or older.
* Histopathologically confirmed glioma.
* Received standard postoperative treatment or routine clinical treatment.
* New or enlarged contrast-enhancing lesion on follow-up MRI suggestive of tumor progression.
* Able to undergo routine MRI, three-dimensional arterial spin labeling (3D-ASL), and time-dependent diffusion MRI (TDD-MRI).
* MRI image quality sufficient for image processing, registration, lesion segmentation, and quantitative parameter extraction.
* Written informed consent provided by the participant or legally authorized representative.

Exclusion Criteria:

* Incomplete clinical, pathological, or imaging follow-up data.
* MRI images with severe motion artifacts, susceptibility artifacts, or geometric distortion affecting image analysis.
* Failure to complete routine MRI, 3D-ASL, or TDD-MRI examinations according to the study protocol.
* Lesions too small or poorly defined for reliable three-dimensional volume-of-interest delineation and parameter extraction.
* Any other condition judged by the investigators to make participation inappropriate.