VB.NET modificare un file CSV

[carriban]

Grazie mille per la risposta, ma non riesco a capire cosa intendi per
Dim out As New List<String>()

ho provato a modificare il tuo codice in questo modo :

        Dim out As New DataGridViewRow
        Using fs As New StreamReader(ApriPath)
            While True
                Dim r1 As String = fs.ReadLine(2)
                Dim r2 As String = fs.ReadLine(3)
                If r2 Is Nothing Then Exit While
                Dim s1() As String = r1.Split(";"c)
                Dim s2() As String = r2.Split(";"c)
                If CInt(s1(12)) + CInt(s2(12)) < 121 Then
                    DataGridView2.Rows.Add(r1)
                    DataGridView2.Rows.Add(r2)
                End If
            End While
        End Using

VS genera un errore : indici oltre i limiti della matrice.