Convex Hull analysis

Use this analysis to measure the size of a microvascular network.

The program measures the size of the network by interpreting a branched structure as a solid object controlling a given amount of physical space. The amount of physical space is defined in terms of volume, surface area, area, and/or perimeter.

A convex polygon is generated by connecting the tips of the distal segments. The volume and surface area of the polygon are reported.

Another way to think about the analysis is to imagine a plastic sheet wrapped around the entire neuron, with the plastic stretched tightly between the most distal points of adjacent processes. The volume encased by this plastic sheet is the volume calculated by the 3D convex hull analysis, with the surface area reported as well.

Procedure

1. Open the data file.
2. Select the structures to analyze (see Selecting structures).
3. Select Analyze>Convex Hull to display the Convex Hull Analysis window.

 

To analyze individual vessels, select the vessels individually and perform a separate Convex Hull analysis for each vessel.

References

Rodieck, R. W. (1973). The vertebrate retina: Principles of structure and function. Oxford, England: W. H. Freeman.