An improved, computer-based method to automatically track internal and external diameter of isolated microvessels

Area of Science:

• Physiology
• Biomedical Engineering
• Microcirculation Research

Background:

• Accurate measurement of microvessel diameter is crucial for understanding vascular function.
• Existing methods for diameter tracking can be labor-intensive and prone to inaccuracies, especially under dynamic conditions.

Purpose of the Study:

• To develop and validate an automated diameter tracking method for isolated microvessels.
• The method, named Vessel Track, is designed for microvessels with internal diameters less than 100 micrometers.

Main Methods:

• Implemented an algorithm combining thresholding and iterative regression on a standard PC.
• The algorithm detects outer diameter and calculates inner diameter based on an incompressible vessel wall assumption.
• User defines a tracking window, and initial inner diameter is measured manually.

Main Results:

• Vessel Track accurately tracked arteriolar dimensions during significant vasodilation and vasoconstriction.
• The system provided more accurate, lower-noise recordings compared to manual video calipers and analog analyzers.
• Demonstrated accurate measurement of large-amplitude vasomotion in lymphatic vessels at ~30 Hz.

Conclusions:

• Vessel Track is a valuable tool for automated diameter tracking of isolated microvessels.
• The method offers fast, stable measurements of internal diameter, even with irregular lumen geometry.
• Suitable for studies involving arterioles, venules, and lymphatic vessels.