The C1TreeView class is a StackPanel with two elements:

• A header that represents the actual node, with a button to collapse and expand the children.
• A body that is another StackPanel and contains other nodes.

You can add images to a node by grabbing its first child (the header), casting that to a StackPanel, and inserting an image element at whatever position you prefer. For example:

Dim nodeHeader As StackPanel = TryCast(TreeNode.Children(0), StackPanel)
nodeHeader.Children.Insert(0, myImage)

StackPanel nodeHeader = TreeNode.Children[0] as StackPanel;
nodeHeader.Children.Insert(0, myImage);