Inverse Perfusion Requirements of Supra- and Infratentorial Brain Metastases Formation.

Area of Science:

• Neuro-oncology
• Radiology
• Medical imaging

Background:

• Brain metastases (BM) often develop at vascular border zones and the gray-white matter junction.
• Microvascular lesions are associated with a protective effect against BM development.

Purpose of the Study:

• To investigate the relationship between blood perfusion and the spatial distribution of brain metastases.
• To explore differing pathophysiological mechanisms for supratentorial and infratentorial BM.

Main Methods:

• Created an average CT perfusion atlas from 107 healthy individuals.
• Extracted voxel-wise perfusion values from BM-negative and BM-positive regions in 100 untreated patients with 809 BM (confirmed by MRI).
• Compared regional perfusion values using an independent t-test.

Main Results:

• Supratentorial BM were found in regions with lower cerebral blood volume/flow (CBV/CBF) and longer mean transit time/time to peak (MTT/TTP).
• Infratentorial BM were identified in regions with higher CBV/CBF and shorter MTT/TTP.
• Both findings were statistically significant (p < 0.001).

Conclusions:

• Distinct pathophysiological mechanisms likely underlie supratentorial and infratentorial BM development.
• Observed inverse perfusion patterns may relate to variations in vascular supply, hemodynamic needs, or angiogenic factor production.