diff --git a/Modules/ImageStatisticsUI/Qmitk/QmitkHistogramVisualizationWidget.cpp b/Modules/ImageStatisticsUI/Qmitk/QmitkHistogramVisualizationWidget.cpp
index ec3d8612a6..b6d877b6b6 100644
--- a/Modules/ImageStatisticsUI/Qmitk/QmitkHistogramVisualizationWidget.cpp
+++ b/Modules/ImageStatisticsUI/Qmitk/QmitkHistogramVisualizationWidget.cpp
@@ -1,127 +1,127 @@
 /*===================================================================
 
 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 "QmitkHistogramVisualizationWidget.h"
 
 #include <qclipboard>
 
-HistogramVisualizationWidget::HistogramVisualizationWidget(QWidget* parent) : QWidget(parent)
+QmitkHistogramVisualizationWidget::QmitkHistogramVisualizationWidget(QWidget* parent) : QWidget(parent)
 {
 	m_Controls.setupUi(this);
 	CreateConnections();
 }
 
-void HistogramVisualizationWidget::setHistogram(itk::Statistics::Histogram<double>::ConstPointer histogram, std::string dataLabel)
+void QmitkHistogramVisualizationWidget::setHistogram(itk::Statistics::Histogram<double>::ConstPointer histogram, const std::string& dataLabel)
 {
 	if (histogram == nullptr)
 		return;
 
 	m_Histogram = histogram;
 	m_Controls.chartWidget->AddData2D(ConvertHistogramToMap(m_Histogram), dataLabel);
 	m_Controls.chartWidget->SetChartType(dataLabel, QmitkChartWidget::ChartType::bar);
 	m_Controls.chartWidget->SetXAxisLabel("Gray value");
 	m_Controls.chartWidget->SetYAxisLabel("Frequency");
 
 	m_Controls.chartWidget->Show(m_Controls.checkBoxShowSubchart->isChecked());
 	SetGUIElementsEnabled(true);
 }
 
-void HistogramVisualizationWidget::Reset()
+void QmitkHistogramVisualizationWidget::Reset()
 {
 	m_Controls.chartWidget->Clear();
 	SetGUIElementsEnabled(false);
 }
 
-void HistogramVisualizationWidget::CreateConnections()
+void QmitkHistogramVisualizationWidget::CreateConnections()
 {
-	connect(m_Controls.buttonCopyHistogramToClipboard, &QPushButton::clicked, this, &HistogramVisualizationWidget::OnClipboardButtonClicked);
-	connect(m_Controls.checkBoxUseDefaultNBins, &QCheckBox::clicked, this, &HistogramVisualizationWidget::OnDefaultNBinsCheckBoxChanged);
-	connect(m_Controls.spinBoxNBins, &QSpinBox::editingFinished, this, &HistogramVisualizationWidget::OnNBinsSpinBoxValueChanged);
-	connect(m_Controls.checkBoxShowSubchart, &QCheckBox::clicked, this, &HistogramVisualizationWidget::OnShowSubchartCheckBoxChanged);
+	connect(m_Controls.buttonCopyHistogramToClipboard, &QPushButton::clicked, this, &QmitkHistogramVisualizationWidget::OnClipboardButtonClicked);
+	connect(m_Controls.checkBoxUseDefaultNBins, &QCheckBox::clicked, this, &QmitkHistogramVisualizationWidget::OnDefaultNBinsCheckBoxChanged);
+	connect(m_Controls.spinBoxNBins, &QSpinBox::editingFinished, this, &QmitkHistogramVisualizationWidget::OnNBinsSpinBoxValueChanged);
+	connect(m_Controls.checkBoxShowSubchart, &QCheckBox::clicked, this, &QmitkHistogramVisualizationWidget::OnShowSubchartCheckBoxChanged);
 }
 
-void HistogramVisualizationWidget::SetGUIElementsEnabled(bool enabled)
+void QmitkHistogramVisualizationWidget::SetGUIElementsEnabled(bool enabled)
 {
 	this->setEnabled(enabled);
 	m_Controls.groupBoxHistogram->setEnabled(enabled);
 	m_Controls.groupBoxPlot->setEnabled(enabled);
 	m_Controls.checkBoxShowSubchart->setEnabled(enabled);
 	m_Controls.checkBoxUseDefaultNBins->setEnabled(enabled);
 	m_Controls.spinBoxNBins->setEnabled(!m_Controls.checkBoxUseDefaultNBins->isChecked());
 	m_Controls.buttonCopyHistogramToClipboard->setEnabled(enabled);
 }
 
-std::map<double, double> HistogramVisualizationWidget::ConvertHistogramToMap(itk::Statistics::Histogram<double>::ConstPointer histogram) const
+std::map<double, double> QmitkHistogramVisualizationWidget::ConvertHistogramToMap(itk::Statistics::Histogram<double>::ConstPointer histogram) const
 {
 	std::map<double, double> histogramMap;
 	if (histogram)
 	{
 		auto endIt = histogram->End();
 		auto it = histogram->Begin();
 
 		// generating Lists of measurement and frequencies
 		for (; it != endIt; ++it)
 		{
 			double frequency = it.GetFrequency();
 			double measurement = it.GetMeasurementVector()[0];
 			histogramMap.emplace(measurement, frequency);
 		}
 
 	}
 	return histogramMap;
 }
 
-void HistogramVisualizationWidget::OnClipboardButtonClicked()
+void QmitkHistogramVisualizationWidget::OnClipboardButtonClicked()
 {
 	if (m_Histogram)
 	{
 		QApplication::clipboard()->clear();
 		QString clipboard("Measurement \t Frequency\n");
 		auto iter = m_Histogram->Begin();
 		auto iterEnd = m_Histogram->End();
 		for (; iter != iterEnd; ++iter)
 		{
 			clipboard = clipboard.append("%L1 \t %L2\n")
 				.arg(iter.GetMeasurementVector()[0], 0, 'f', 2)
 				.arg(iter.GetFrequency());
 		}
 
 		QApplication::clipboard()->setText(clipboard, QClipboard::Clipboard);
 	}
 }
 
-void HistogramVisualizationWidget::OnDefaultNBinsCheckBoxChanged()
+void QmitkHistogramVisualizationWidget::OnDefaultNBinsCheckBoxChanged()
 {
 	if (m_Controls.checkBoxUseDefaultNBins->isChecked())
 	{
 		m_Controls.spinBoxNBins->setEnabled(false);
 		m_Controls.spinBoxNBins->setValue(100);
 	}
 	else
 	{
 		m_Controls.spinBoxNBins->setEnabled(true);
 	}
 }
 
-void HistogramVisualizationWidget::OnNBinsSpinBoxValueChanged()
+void QmitkHistogramVisualizationWidget::OnNBinsSpinBoxValueChanged()
 {
 	emit RequestHistogramUpdate(m_Controls.spinBoxNBins->value());
 }
 
-void HistogramVisualizationWidget::OnShowSubchartCheckBoxChanged()
+void QmitkHistogramVisualizationWidget::OnShowSubchartCheckBoxChanged()
 {
 	m_Controls.chartWidget->Show(m_Controls.checkBoxShowSubchart->isChecked());
 }
\ No newline at end of file
diff --git a/Modules/ImageStatisticsUI/Qmitk/QmitkHistogramVisualizationWidget.h b/Modules/ImageStatisticsUI/Qmitk/QmitkHistogramVisualizationWidget.h
index 8afedb4309..0266f964aa 100644
--- a/Modules/ImageStatisticsUI/Qmitk/QmitkHistogramVisualizationWidget.h
+++ b/Modules/ImageStatisticsUI/Qmitk/QmitkHistogramVisualizationWidget.h
@@ -1,66 +1,71 @@
 /*===================================================================
 
 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.
 
 ===================================================================*/
-#pragma once
+#ifndef QmitkHistogramVisualizationWidget_H__INCLUDED
+#define QmitkHistogramVisualizationWidget_H__INCLUDED
 
 //Qt
 #include <QWidget>
 
 #include <MitkImageStatisticsUIExports.h>
 #include <ui_QmitkHistogramVisualizationControls.h>
 
 //itk
 #include <itkHistogram.h>
 
-class MITKIMAGESTATISTICSUI_EXPORT HistogramVisualizationWidget : public QWidget
+/**
+* \brief Widget for displaying Histograms.
+*/
+
+class MITKIMAGESTATISTICSUI_EXPORT QmitkHistogramVisualizationWidget : public QWidget
 {
 	Q_OBJECT
 
 public:
-	HistogramVisualizationWidget(QWidget* parent = nullptr);
-	/** \brief Draws the histogram and enables the GUI elements */
-	void setHistogram(itk::Statistics::Histogram<double>::ConstPointer histogram, std::string dataLabel);
-	/** \brief Clears the histogram and disables all GUI elements */
+	QmitkHistogramVisualizationWidget(QWidget* parent = nullptr);
+	/** \brief Draws the histogram and enables the GUI elements. */
+	void setHistogram(itk::Statistics::Histogram<double>::ConstPointer histogram, const std::string& dataLabel);
+	/** \brief Clears the histogram and disables all GUI elements. */
 	void Reset();
 
 signals:
-	/**
-	* \brief Signal to be emitted when the number of bins is changed by the user. The HistogramCalculator should connect to this signal and recalculate the data accordingly.
-	*/
+	/** \brief Signal to be emitted when the number of bins is changed by the user. The HistogramCalculator should connect to this signal and recalculate the data accordingly. */
 	void RequestHistogramUpdate(unsigned int nBins);
 
 private:
 
 	void CreateConnections();
 
 	void SetGUIElementsEnabled(bool enabled);
-
+	/** \brief Helper function to convert the histogram in order to forward it to the ChartWidget. */
 	std::map<double, double> ConvertHistogramToMap(itk::Statistics::Histogram<double>::ConstPointer histogram) const;
 
 //slots
-	/** \brief  Saves the histogram to the clipboard */
+	/** \brief  Saves the histogram to the clipboard. */
 	void OnClipboardButtonClicked();
-	/** \brief Toogle GUI elements if histogram default bin size checkbox value changed. */
+	/** \brief Enables / Disables SpinBox to change the number of bins. */
 	void OnDefaultNBinsCheckBoxChanged();
-
+	/** \brief Emits the signal RequestHistogramUpdate(unsigned int nBins) with the updated value. */
 	void OnNBinsSpinBoxValueChanged();
-
+	/** \brief Shows / Hides the subchart. */
 	void OnShowSubchartCheckBoxChanged();
 
 private:
 	Ui::QmitkHistogramVisualizationControls m_Controls;
 
 	itk::Statistics::Histogram<double>::ConstPointer m_Histogram;
-};
\ No newline at end of file
+};
+
+#endif //QmitkHistogramVisualizationWidget_H__INCLUDED
\ No newline at end of file
diff --git a/Plugins/org.mitk.gui.qt.measurementtoolbox/src/internal/QmitkImageStatisticsReloadedViewControls.ui b/Plugins/org.mitk.gui.qt.measurementtoolbox/src/internal/QmitkImageStatisticsReloadedViewControls.ui
index c39c1edebd..afdc1af00c 100644
--- a/Plugins/org.mitk.gui.qt.measurementtoolbox/src/internal/QmitkImageStatisticsReloadedViewControls.ui
+++ b/Plugins/org.mitk.gui.qt.measurementtoolbox/src/internal/QmitkImageStatisticsReloadedViewControls.ui
@@ -1,225 +1,226 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <ui version="4.0">
  <class>QmitkImageStatisticsReloadedViewControls</class>
  <widget class="QWidget" name="QmitkImageStatisticsReloadedViewControls">
   <property name="enabled">
    <bool>true</bool>
   </property>
   <property name="geometry">
    <rect>
     <x>0</x>
     <y>0</y>
     <width>548</width>
     <height>853</height>
    </rect>
   </property>
   <property name="windowTitle">
    <string>Form</string>
   </property>
   <layout class="QVBoxLayout" name="verticalLayout_4">
    <item>
     <layout class="QGridLayout" name="gridLayout_4" columnstretch="0,0">
      <property name="sizeConstraint">
       <enum>QLayout::SetMinimumSize</enum>
      </property>
      <property name="spacing">
       <number>4</number>
      </property>
      <item row="0" column="1">
       <widget class="QmitkDataStorageComboBox" name="imageSelector">
        <property name="sizePolicy">
         <sizepolicy hsizetype="Minimum" vsizetype="Fixed">
          <horstretch>0</horstretch>
          <verstretch>0</verstretch>
         </sizepolicy>
        </property>
        <property name="autoFillBackground">
         <bool>false</bool>
        </property>
       </widget>
      </item>
      <item row="0" column="0">
       <widget class="QLabel" name="label_calibrationImage">
        <property name="sizePolicy">
         <sizepolicy hsizetype="Maximum" vsizetype="Preferred">
          <horstretch>0</horstretch>
          <verstretch>0</verstretch>
         </sizepolicy>
        </property>
        <property name="palette">
         <palette>
          <active>
           <colorrole role="WindowText">
            <brush brushstyle="SolidPattern">
             <color alpha="255">
              <red>0</red>
              <green>0</green>
              <blue>0</blue>
             </color>
            </brush>
           </colorrole>
          </active>
          <inactive>
           <colorrole role="WindowText">
            <brush brushstyle="SolidPattern">
             <color alpha="255">
              <red>0</red>
              <green>0</green>
              <blue>0</blue>
             </color>
            </brush>
           </colorrole>
          </inactive>
          <disabled>
           <colorrole role="WindowText">
            <brush brushstyle="SolidPattern">
             <color alpha="255">
              <red>120</red>
              <green>120</green>
              <blue>120</blue>
             </color>
            </brush>
           </colorrole>
          </disabled>
         </palette>
        </property>
        <property name="text">
         <string>Image:</string>
        </property>
       </widget>
      </item>
      <item row="1" column="0">
       <widget class="QLabel" name="label_maskImage">
        <property name="sizePolicy">
         <sizepolicy hsizetype="Maximum" vsizetype="Preferred">
          <horstretch>0</horstretch>
          <verstretch>0</verstretch>
         </sizepolicy>
        </property>
        <property name="palette">
         <palette>
          <active>
           <colorrole role="WindowText">
            <brush brushstyle="SolidPattern">
             <color alpha="255">
              <red>0</red>
              <green>0</green>
              <blue>0</blue>
             </color>
            </brush>
           </colorrole>
          </active>
          <inactive>
           <colorrole role="WindowText">
            <brush brushstyle="SolidPattern">
             <color alpha="255">
              <red>0</red>
              <green>0</green>
              <blue>0</blue>
             </color>
            </brush>
           </colorrole>
          </inactive>
          <disabled>
           <colorrole role="WindowText">
            <brush brushstyle="SolidPattern">
             <color alpha="255">
              <red>120</red>
              <green>120</green>
              <blue>120</blue>
             </color>
            </brush>
           </colorrole>
          </disabled>
         </palette>
        </property>
        <property name="text">
         <string>Mask image:</string>
        </property>
       </widget>
      </item>
      <item row="1" column="1">
       <widget class="QmitkDataStorageComboBox" name="maskImageSelector">
        <property name="sizePolicy">
         <sizepolicy hsizetype="Minimum" vsizetype="Fixed">
          <horstretch>0</horstretch>
          <verstretch>0</verstretch>
         </sizepolicy>
        </property>
        <property name="autoFillBackground">
         <bool>false</bool>
        </property>
       </widget>
      </item>
     </layout>
    </item>
    <item>
     <widget class="QGroupBox" name="groupBox_statistics">
      <property name="enabled">
       <bool>false</bool>
      </property>
      <property name="title">
       <string>Statistics</string>
      </property>
      <layout class="QVBoxLayout" name="verticalLayout">
       <property name="leftMargin">
        <number>9</number>
       </property>
       <property name="rightMargin">
        <number>9</number>
       </property>
       <property name="bottomMargin">
        <number>9</number>
       </property>
      </layout>
     </widget>
    </item>
    <item>
     <widget class="QGroupBox" name="groupBox_histogram">
      <property name="enabled">
       <bool>false</bool>
      </property>
      <property name="minimumSize">
       <size>
        <width>400</width>
        <height>450</height>
       </size>
      </property>
      <property name="title">
       <string>Histogram</string>
      </property>
      <property name="checkable">
       <bool>false</bool>
      </property>
      <layout class="QVBoxLayout" name="verticalLayout_3">
       <item>
-       <widget class="HistogramVisualizationWidget" name="widget" native="true"/>
+       <widget class="QmitkHistogramVisualizationWidget" name="widget" native="true"/>
       </item>
      </layout>
     </widget>
    </item>
    <item>
     <spacer name="verticalSpacer">
      <property name="orientation">
       <enum>Qt::Vertical</enum>
      </property>
      <property name="sizeHint" stdset="0">
       <size>
        <width>20</width>
        <height>40</height>
       </size>
      </property>
     </spacer>
    </item>
   </layout>
  </widget>
  <customwidgets>
   <customwidget>
-   <class>QmitkDataStorageComboBox</class>
-   <extends>QComboBox</extends>
-   <header location="global">QmitkDataStorageComboBox.h</header>
+   <class>QmitkHistogramVisualizationWidget</class>
+   <extends>QWidget</extends>
+   <header location="global">QmitkHistogramVisualizationWidget.h</header>
+   <container>1</container>
   </customwidget>
  </customwidgets>
  <resources/>
  <connections/>
 </ui>