In order to run PeriopSim VR using a VIVE headset depends on SteamVR software to be running and configured.
Detailed information on VIVE setup can be found on VIVE's website here:
It is important to note that a Steam account will be required for setup. After setup and configuration is completed PeriopSim VR can be installed.
The latest version of PeriopSim VR can be downloaded from the PeriopSim Website. Once the installer is downloaded run the installer. It will provide a warning. Click on "More" then click on "Run Anyway". After the installation has completed it will run PeriopSim VR.
PeriopSim VR can be run from the desktop shortcut created during the installation. Running PeriopSim VR should automatically launch SteamVR.