Index: QmitkLevelWindowWidgetContextMenu.cpp
===================================================================
--- QmitkLevelWindowWidgetContextMenu.cpp	(revision 27702)
+++ QmitkLevelWindowWidgetContextMenu.cpp	(working copy)
@@ -203,7 +203,9 @@
         if (node->IsVisible(NULL) == false)
           continue;
         mitk::LevelWindowProperty::Pointer levelWindowProperty = dynamic_cast<mitk::LevelWindowProperty*>(node->GetProperty("levelwindow"));
-        if (levelWindowProperty.IsNotNull())
+        bool isHelperObject = false;
+        node->GetBoolProperty("helper object", isHelperObject);
+        if (levelWindowProperty.IsNotNull() && !isHelperObject)
         {
           std::string name;
           node->GetName(name);
@@ -281,7 +283,9 @@
       if (node)
       {
         mitk::LevelWindowProperty::Pointer levelWindowProperty = dynamic_cast<mitk::LevelWindowProperty*>(node->GetProperty("levelwindow"));
-        if (levelWindowProperty.IsNotNull())
+        bool isHelperObject = false;
+        node->GetBoolProperty("helper object", isHelperObject);
+        if (levelWindowProperty.IsNotNull() && !isHelperObject)
         {
           std::string name;
           node->GetName(name);