Obtaining if Text Style name exists

Running Select 10

How can I via VBA find out the name of the text file in a current .dgn

I do know how to do manually by Element>Text Styles and see them , but can you use VBA to know there are styles loaded ?

Example: I know if they are there is a Style name DFS_250x250UL  without manually looking is it possible to get VBA to check its existance

than if it was not the macro would import the .dgnlib  which is named "DupontFontStyles.dgnlib"