Branching Pattern of the Cerebral Arterial Tree

Area of Science:

• Anatomy
• Biophysics
• Medical Imaging

Background:

• Quantitative data on human cerebral arterial branching is limited, especially in the 1.0-0.1 mm radius range.
• Understanding these patterns is vital for developing accurate mathematical blood flow models.

Purpose of the Study:

• To collect quantitative data on cerebral arterial branching patterns in the 1.0-0.1 mm radius range.
• To investigate if the human cerebral arterial tree follows the principle of minimal work (Murray's Law).

Main Methods:

• Utilized 7 Tesla MRI and 9.4 Tesla MRI on corrosion casts for detailed imaging of arterial segments and bifurcations.
• Employed semi-automatic and manual measurement techniques on MRI scans and a fresh dissected arterial tree.
• Quantified 1,294 bifurcations and 2,031 segments using 7T-MRI, and 1,147 bifurcations and 1,150 segments using 9.4T-MRI.

Main Results:

• Observed significant variation in branching pattern parameters, including asymmetry ratio, area ratio, length-radius ratio, and tapering.
• Measurement techniques, sample size, and location influenced observed variations.
• Confirmed that the human cerebral arterial tree complies with the principle of minimum work.

Conclusions:

• The study provides essential quantitative data on cerebral arterial branching in a previously under-characterized size range.
• The findings validate the application of the principle of minimum work to the human cerebral arterial system.
• These data are fundamental for advancing computational fluid dynamics models of cerebral blood flow.