Automated Segmentation and Connectivity Analysis for Normal Pressure Hydrocephalus

Table 1

Network coefficients used for NPH vs. non-NPH comparison. All coefficients included a weighted and a binary version, except for the network density.

Network coefficients

Brief description

Density

Fraction of present connections to possible connections

Clustering coeff. average

Fraction of triangles (node’s neighbors that are also neighbors of each other) around a node (vertex connected to other vertices)

Transitivity

Ratio of triangles to triplets (three nodes that are connected by either two or three ties) in the network

Network characteristic path length

Average shortest path length in the network

Small-worldness

Average path length of the network divided by the average path length of a random network with the same node and edge (connection between two nodes) count as the network being analyzed

Global efficiency

Average efficiency (1/distance) between all sets of nodes

Diameter of graph

Maximum eccentricity (maximal shortest path length between a node and any other node)

Radius of graph

Minimum eccentricity

Assortativity coefficient

Correlation of the degree (number of overall connections) of connected nodes

Rich club,

Fraction of edges that connect nodes of degree or higher out of the maximum number of edges that such nodes might share