diff --git a/Modules/SegmentationUI/Qmitk/QmitkOtsuTool3DGUI.cpp b/Modules/SegmentationUI/Qmitk/QmitkOtsuTool3DGUI.cpp
index bfd9f3073a..069e878a19 100644
--- a/Modules/SegmentationUI/Qmitk/QmitkOtsuTool3DGUI.cpp
+++ b/Modules/SegmentationUI/Qmitk/QmitkOtsuTool3DGUI.cpp
@@ -1,154 +1,155 @@
 /*===================================================================
 
 The Medical Imaging Interaction Toolkit (MITK)
 
 Copyright (c) German Cancer Research Center,
 Division of Medical and Biological Informatics.
 All rights reserved.
 
 This software is distributed WITHOUT ANY WARRANTY; without
 even the implied warranty of MERCHANTABILITY or FITNESS FOR
 A PARTICULAR PURPOSE.
 
 See LICENSE.txt or http://www.mitk.org for details.
 
 ===================================================================*/
 
 #include "QmitkOtsuTool3DGUI.h"
 #include "QmitkConfirmSegmentationDialog.h"
 
 #include <qlabel.h>
 #include <qspinbox.h>
 #include <qpushbutton.h>
 #include <qlayout.h>
 #include <qlistwidget.h>
 #include <QMessageBox>
 
 MITK_TOOL_GUI_MACRO(SegmentationUI_EXPORT, QmitkOtsuTool3DGUI, "")
 
 QmitkOtsuTool3DGUI::QmitkOtsuTool3DGUI()
 :QmitkToolGUI(),
 m_NumberOfRegions(0)
 {
   m_Controls.setupUi(this);
 
   connect( m_Controls.previewButton, SIGNAL(clicked()), this, SLOT(OnSpinboxValueAccept()));
   connect(m_Controls.m_selectionListWidget, SIGNAL(itemClicked(QListWidgetItem*)),
           this, SLOT(OnItemSelectionChanged(QListWidgetItem*)));
   connect( m_Controls.m_ConfSegButton, SIGNAL(clicked()), this, SLOT(OnSegmentationRegionAccept()));
   connect( this, SIGNAL(NewToolAssociated(mitk::Tool*)), this, SLOT(OnNewToolAssociated(mitk::Tool*)) );
 }
 
 QmitkOtsuTool3DGUI::~QmitkOtsuTool3DGUI()
 {
 
 }
 
 void QmitkOtsuTool3DGUI::OnItemSelectionChanged(QListWidgetItem* item)
 {
   if (m_SelectedItem == item)
   {
     m_SelectedItem = 0;
     m_Controls.m_selectionListWidget->clearSelection();
+    m_Controls.m_ConfSegButton->setEnabled( false );
     m_OtsuTool3DTool->ShowMultiLabelResultNode(true);
     return;
   }
 
   m_SelectedItem = item;
 
   if (m_OtsuTool3DTool.IsNotNull())
   {
     // TODO update preview of region
     m_OtsuTool3DTool->UpdateBinaryPreview(m_SelectedItem->text().toInt());
     if ( !m_Controls.m_selectionListWidget->selectedItems().empty() )
     {
       m_Controls.m_ConfSegButton->setEnabled( true );
     }
     else
     {
       m_Controls.m_ConfSegButton->setEnabled( false );
     }
   }
 }
 
 void QmitkOtsuTool3DGUI::OnNewToolAssociated(mitk::Tool* tool)
 {
   m_OtsuTool3DTool = dynamic_cast<mitk::OtsuTool3D*>( tool );
 }
 
 void QmitkOtsuTool3DGUI::OnSegmentationRegionAccept()
 {
   QmitkConfirmSegmentationDialog dialog;
   QString segName = QString::fromStdString(m_OtsuTool3DTool->GetCurrentSegmentationName());
 
   dialog.SetSegmentationName(segName);
   int result = dialog.exec();
 
   switch(result)
   {
   case QmitkConfirmSegmentationDialog::CREATE_NEW_SEGMENTATION:
     m_OtsuTool3DTool->SetOverwriteExistingSegmentation(false);
     break;
   case QmitkConfirmSegmentationDialog::OVERWRITE_SEGMENTATION:
     m_OtsuTool3DTool->SetOverwriteExistingSegmentation(true);
     break;
   case QmitkConfirmSegmentationDialog::CANCEL_SEGMENTATION:
     return;
   }
 
   if (m_OtsuTool3DTool.IsNotNull() && m_Controls.m_selectionListWidget->currentItem() != NULL)
   {
     m_OtsuTool3DTool->ConfirmSegmentation();
     m_OtsuTool3DTool->Deactivated();
   }
 }
 
 void QmitkOtsuTool3DGUI::OnSpinboxValueAccept()
 {
   if( m_NumberOfRegions == m_Controls.m_Spinbox->value() )
     return;
 
   if (m_OtsuTool3DTool.IsNotNull())
   {
     try
     {
       m_NumberOfRegions = m_Controls.m_Spinbox->value();
       int proceed;
 
       QMessageBox* messageBox = new QMessageBox(QMessageBox::Question, NULL, "The otsu segmentation computation may take several minutes depending on the number of Regions you selected. Proceed anyway?", QMessageBox::Ok | QMessageBox::Cancel);
       if (m_NumberOfRegions >= 5)
       {
         proceed = messageBox->exec();
         if (proceed != QMessageBox::Ok) return;
       }
       this->setCursor(Qt::WaitCursor);
       m_OtsuTool3DTool->RunSegmentation( m_NumberOfRegions );
       this->setCursor(Qt::ArrowCursor);
     }
     catch( ... )
     {
       this->setCursor(Qt::ArrowCursor);
       QMessageBox* messageBox = new QMessageBox(QMessageBox::Critical, NULL, "itkOtsuFilter error: image dimension must be in {2, 3} and no RGB images can be handled.");
       messageBox->exec();
       delete messageBox;
       return;
     }
     //insert regions into widget
     QString itemName;
     QListWidgetItem* item;
     m_Controls.m_selectionListWidget->clear();
     for(int i=0; i<m_Controls.m_Spinbox->value(); ++i)
     {
       itemName = QString::number(i);
       item = new QListWidgetItem(itemName);
       m_Controls.m_selectionListWidget->addItem(item);
     }
   }
 }
 
 void QmitkOtsuTool3DGUI::OnVolumePreviewChecked(int state)
 {
   if (state == 1)
   {
   }
 }