VB.NET to Acrobat Communication

I have established communication from my vb.net application to acrobat using the following:

Dim AcroApp As Acrobat.CAcroApp
Dim theForm As Acrobat.CAcroPDDoc
Dim jso As Object

AcroApp = CreateObject("AcroExch.App")
theForm = CreateObject("AcroExch.PDDoc")

theForm.Open(filename)
jso = theForm.GetJSObject

Is it possible to communicate from acrobat to this vb.net application.

In other words, if something changes on my pdf i would like to do something on my vb.net application.

Any guidance would be helpful.