Using back references to find data type naming standards violations

Hello,

Using Visual Studio 2015, the first following line RegEx finds the second following line Dim statement:
Dim L_V_Scalar_(Integer)_Item As \1
Dim L_V_Scalar_Integer_Item As Integer

Is there a way to write a back reference with a ^ not operator to find the following violations of my naming convention?
Dim L_V_Scalar_Integer_Item As String

I tried the following regular expressions, but they do not work:
Dim L_V_Scalar_(Integer)_Item As ^\1
Dim L_V_Scalar_(Integer)_Item As [^\1]

Many thanks.

Keith