Jak zjistit zda je vyplněn komentář v Excelu?

Sub Test()
   'Test zda bunka B3 ma komentar
   If IsNothing(Range("B3").Comment) Then
     'Nevyplnen
   Else
     'Vyplnen
   End If
End Sub

Public Function IsNothing _
                  (pvarToTest As Variant) _
                As Boolean
    On Error Resume Next
    IsNothing = (pvarToTest Is Nothing)
    Err.Clear
    On Error GoTo 0
End Function 'IsNothing