Use the built in Visual Basic
something like this: fix up the paths parts yourself.
Sub a()
Dim docs As New Collection
' add the paths of your documents here, use more script if you want wildcard etc
docs.Add ("C:\Users\[username]\Desktop\New folder (4)\drawing2.vsd")
docs.Add ("C:\Users\[username]\Desktop\New folder (4)\drawing3.vsd")
For Each d In docs
Dim doc As Document
Set doc = Documents.Add(d)
Dim p As Page
For Each p In doc.Pages
Dim n As String
' change this for the output path and format of your choice
n = "C:\Users\[username]\Desktop\New folder (4)\" & doc.Name & " " & p.Index & ".png"
p.Export (n)
Next
Next
End sub