Fiber density mapping of gliomas: histopathologic evaluation of a diffusion-tensor imaging data processing method.

Area of Science:

• Neuroimaging
• Oncology
• Histopathology

Background:

• Gliomas extensively infiltrate and destroy brain white matter (WM).
• Accurate assessment of WM damage is crucial for effective glioma treatment planning.
• Current methods may not fully capture the extent of WM structural integrity loss.

Purpose of the Study:

• To evaluate fiber density mapping (FDM) for quantifying white matter (WM) destruction in gliomas.
• To assess WM structures in the center, transition zone, and border zone of tumors.
• To correlate FDM findings with histopathologic data.

Main Methods:

• Retrospective study of 20 glioma patients using diffusion-tensor imaging (DTI) and MR imaging-guided biopsies.
• Fiber density mapping (FDM) involved tensor diagonalization, whole-brain fiber reconstruction, and density calculation.
• Coregistration of FDM and MR imaging data allowed correlation with histopathology.

Main Results:

• Strong negative correlations found between FDM and tumor cell number (R = -0.825) and tumor infiltration (R = -0.909).
• Complete WM destruction observed with >=60% tumor infiltration or >=150 tumor cells.
• A fiber density value of 18 identified potentially functional, yet infiltrated, fiber structures.

Conclusions:

• Fiber density mapping (FDM) offers histological insights into white matter (WM) structure.
• FDM can aid in preventing post-treatment neurological deficits during glioma therapy planning.