private void RotateImage(RotationOperation operation)
        {
            vtkImageReslice reslice   = vtkImageReslice.New();
            vtkTransform    transform = vtkTransform.New();

            transform.PostMultiply();

            double[] center = { 75, 100, 0 };
            transform.Translate(-center[0], -center[1], -center[2]);
            if (operation == RotationOperation.Forward)
            {
                transform.RotateZ(90);
            }
            else if (operation == RotationOperation.Back)
            {
                transform.RotateZ(-90);
            }
            transform.Translate(+center[0], +center[1], +center[2]);

            transform.Update();
            reslice.SetInput(_viewer.GetInput());
            reslice.SetResliceTransform(transform);
            reslice.Update();

            _viewer.SetInput(reslice.GetOutput());

            UpdateViewer();
        }