diff --git a/Modules/AlgorithmsExt/src/mitkSegmentationSink.cpp b/Modules/AlgorithmsExt/src/mitkSegmentationSink.cpp
index 004158e57e..aec4a69962 100644
--- a/Modules/AlgorithmsExt/src/mitkSegmentationSink.cpp
+++ b/Modules/AlgorithmsExt/src/mitkSegmentationSink.cpp
@@ -1,95 +1,95 @@
 /*===================================================================
 
 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 "mitkSegmentationSink.h"
 #include "mitkDataStorage.h"
 #include "mitkRenderingManager.h"
 
 namespace mitk
 {
   SegmentationSink::SegmentationSink() {}
   SegmentationSink::~SegmentationSink() {}
   void SegmentationSink::Initialize(const NonBlockingAlgorithm *other)
   {
     Superclass::Initialize(other);
     // sinks should be called explicitly from the tool, because otherwise the order of setting "Input" and "Group node"
     // would matter
     UnDefineTriggerParameter("Input");
 
     // some basedata output
     DataNode::Pointer groupNode;
     bool showResult(true);
 
     if (other)
     {
       other->GetPointerParameter("Group node", groupNode);
       other->GetParameter("Show result", showResult);
     }
 
     SetPointerParameter("Group node", groupNode);
     SetParameter("Show result", showResult);
   }
 
   bool SegmentationSink::ReadyToRun()
   {
     Image::Pointer image;
     GetPointerParameter("Input", image);
 
     DataNode::Pointer groupNode;
     GetPointerParameter("Group node", groupNode);
 
     return image.IsNotNull() && groupNode.IsNotNull();
   }
 
   bool SegmentationSink::ThreadedUpdateFunction() { return true; }
   /// to be called by subclasses when they want to insert some resulting object (binary image, surface, ...) into the
   /// data tree
   void SegmentationSink::InsertBelowGroupNode(mitk::DataNode *node)
   {
     DataNode *groupNode = GetGroupNode();
 
-    if (m_DataStorage.IsNotNull())
+    if (!m_DataStorage.IsExpired())
     {
       if (node)
         node->GetData()->DisconnectPipeline();
-      m_DataStorage->Add(node, groupNode);
+      m_DataStorage.Lock()->Add(node, groupNode);
     }
 
     RenderingManager::GetInstance()->RequestUpdateAll();
   }
 
   DataNode *SegmentationSink::GetGroupNode()
   {
     DataNode::Pointer groupNode;
     GetPointerParameter("Group node", groupNode);
 
     return groupNode.GetPointer();
   }
 
   DataNode *SegmentationSink::LookForPointerTargetBelowGroupNode(const char *name)
   {
     DataNode::Pointer groupNode;
     GetPointerParameter("Group node", groupNode);
 
-    if (groupNode.IsNotNull() && m_DataStorage.IsNotNull())
+    if (groupNode.IsNotNull() && !m_DataStorage.IsExpired())
     {
-      return m_DataStorage->GetNamedDerivedNode(name, groupNode, true);
+      return m_DataStorage.Lock()->GetNamedDerivedNode(name, groupNode, true);
     }
 
     return nullptr;
   }
 
 } // namespace