diff --git a/extensions/dicom-rt/src/index.js b/extensions/dicom-rt/src/index.js
index f6a278007..ff308e133 100644
--- a/extensions/dicom-rt/src/index.js
+++ b/extensions/dicom-rt/src/index.js
@@ -1,11 +1,12 @@
 import React from 'react';
+import { utils } from '@ohif/core';
+
 import init from './init.js';
 import sopClassHandlerModule from './OHIFDicomRTStructSopClassHandler';
 import id from './id.js';
 import RTPanel from './components/RTPanel/RTPanel';
 import { version } from '../package.json';
 
-import { utils } from '@ohif/core';
 const { studyMetadataManager } = utils;
 
 export default {
@@ -42,12 +43,48 @@ export default {
       );
     };
 
+    const RTPanelTabChangedEvent = 'rt-panel-tab-updated';
+
+    /**
+     * Trigger's an event to update the state of the panel's RoundedButtonGroup.
+     *
+     * This is required to avoid extension state
+     * coupling with the viewer's ToolbarRow component.
+     *
+     * @param {object} data
+     */
+    const triggerRTPanelUpdatedEvent = data => {
+      const event = new CustomEvent(RTPanelTabChangedEvent, {
+        detail: data,
+      });
+      document.dispatchEvent(event);
+    };
+
+    const onRTStructsLoaded = ({ detail }) => {
+      const { rtStructDisplaySet, referencedDisplaySet } = detail;
+
+      const studyMetadata = studyMetadataManager.get(
+        rtStructDisplaySet.StudyInstanceUID
+      );
+      const referencedDisplaysets = studyMetadata.getDerivedDatasets({
+        referencedSeriesInstanceUID: referencedDisplaySet.SeriesInstanceUID,
+        Modality: 'RTSTRUCT',
+      });
+      triggerRTPanelUpdatedEvent({
+        badgeNumber: referencedDisplaysets.length,
+        target: 'rt-panel',
+      });
+    };
+
+    document.addEventListener('extensiondicomrtrtloaded', onRTStructsLoaded);
+
     return {
       menuOptions: [
         {
           icon: 'list',
           label: 'RTSTRUCT',
           target: 'rt-panel',
+          stateEvent: RTPanelTabChangedEvent,
           isDisabled: (studies, activeViewport) => {
             if (!studies) {
               return true;
diff --git a/extensions/dicom-rt/src/loadRTStruct.js b/extensions/dicom-rt/src/loadRTStruct.js
index a5323b7f2..d33492fcb 100644
--- a/extensions/dicom-rt/src/loadRTStruct.js
+++ b/extensions/dicom-rt/src/loadRTStruct.js
@@ -90,11 +90,11 @@ export default async function loadRTStruct(
       const sopInstanceUID = ContourImageSequence
         ? ContourImageSequence.ReferencedSOPInstanceUID
         : _getClosestSOPInstanceUID(
-          ContourData,
-          ContourGeometricType,
-          NumberOfContourPoints,
-          imageIdSopInstanceUidPairs
-        );
+            ContourData,
+            ContourGeometricType,
+            NumberOfContourPoints,
+            imageIdSopInstanceUidPairs
+          );
       const imageId = _getImageId(imageIdSopInstanceUidPairs, sopInstanceUID);
 
       if (!imageId) {
@@ -171,7 +171,13 @@ export default async function loadRTStruct(
    * allows us to easily watch the module or the rtstruct loading process in any other component
    * without subscribing to external events.
    */
-  const event = new CustomEvent('extensiondicomrtrtloaded');
+  const event = new CustomEvent('extensiondicomrtrtloaded', {
+    detail: {
+      rtStructDisplaySet,
+      referencedDisplaySet,
+      studies,
+    },
+  });
   document.dispatchEvent(event);
 }
 
@@ -299,7 +305,9 @@ const _getImageId = (imageIdSopInstanceUidPairs, sopInstanceUID) => {
       imageIdSopInstanceUidPairsEntry.sopInstanceUID === sopInstanceUID
   );
 
-  return imageIdSopInstanceUidPairsEntry ? imageIdSopInstanceUidPairsEntry.imageId : null;
+  return imageIdSopInstanceUidPairsEntry
+    ? imageIdSopInstanceUidPairsEntry.imageId
+    : null;
 };
 
 function _getImageIdSopInstanceUidPairsForDisplaySet(
diff --git a/extensions/dicom-segmentation/src/components/SegmentationPanel/SegmentationPanel.js b/extensions/dicom-segmentation/src/components/SegmentationPanel/SegmentationPanel.js
index 02ece632f..d143a3fdd 100644
--- a/extensions/dicom-segmentation/src/components/SegmentationPanel/SegmentationPanel.js
+++ b/extensions/dicom-segmentation/src/components/SegmentationPanel/SegmentationPanel.js
@@ -224,16 +224,20 @@ const SegmentationPanel = ({
         )
       );
     };
-  }, [activeIndex, viewports]);
+  }, [
+    activeIndex,
+    updateSegmentationComboBox,
+    viewports,
+  ]);
 
-  const updateSegmentationComboBox = (e) => {
+  const updateSegmentationComboBox = e => {
     const index = e.detail.activatedLabelmapIndex;
     if (index !== -1) {
       setState(state => ({ ...state, selectedSegmentation: index }));
     } else {
       cleanSegmentationComboBox();
     }
-  }
+  };
 
   const cleanSegmentationComboBox = () => {
     setState(state => ({
@@ -245,7 +249,7 @@ const SegmentationPanel = ({
       isDisabled: true,
       selectedSegmentation: -1,
     }));
-  }
+  };
 
   const refreshSegmentations = () => {
     const activeViewport = getActiveViewport();
@@ -309,7 +313,8 @@ const SegmentationPanel = ({
     );
 
     const filteredReferencedSegDisplaysets = referencedSegDisplaysets.filter(
-      (segDisplay => segDisplay.loadError !== true));
+      segDisplay => segDisplay.loadError !== true
+    );
 
     return filteredReferencedSegDisplaysets.map((displaySet, index) => {
       const {
diff --git a/extensions/dicom-segmentation/src/index.js b/extensions/dicom-segmentation/src/index.js
index 33123b23e..c36d3fab7 100644
--- a/extensions/dicom-segmentation/src/index.js
+++ b/extensions/dicom-segmentation/src/index.js
@@ -1,9 +1,12 @@
 import React from 'react';
+import OHIF from '@ohif/core';
+
 import init from './init.js';
 import toolbarModule from './toolbarModule.js';
 import getSopClassHandlerModule from './getOHIFDicomSegSopClassHandler.js';
 import SegmentationPanel from './components/SegmentationPanel/SegmentationPanel.js';
 import { version } from '../package.json';
+const { studyMetadataManager } = OHIF.utils;
 
 export default {
   /**
@@ -79,12 +82,50 @@ export default {
       );
     };
 
+    const SegmentationPanelTabUpdatedEvent = 'segmentation-panel-tab-updated';
+
+    /**
+     * Trigger's an event to update the state of the panel's RoundedButtonGroup.
+     *
+     * This is required to avoid extension state
+     * coupling with the viewer's ToolbarRow component.
+     *
+     * @param {object} data
+     */
+    const triggerSegmentationPanelTabUpdatedEvent = data => {
+      const event = new CustomEvent(SegmentationPanelTabUpdatedEvent, {
+        detail: data,
+      });
+      document.dispatchEvent(event);
+    };
+
+    const onSegmentationsLoaded = ({ detail }) => {
+      const { segDisplaySet, segMetadata } = detail;
+      const studyMetadata = studyMetadataManager.get(
+        segDisplaySet.StudyInstanceUID
+      );
+      const referencedDisplaysets = studyMetadata.getDerivedDatasets({
+        referencedSeriesInstanceUID: segMetadata.seriesInstanceUid,
+        Modality: 'SEG',
+      });
+      triggerSegmentationPanelTabUpdatedEvent({
+        badgeNumber: referencedDisplaysets.length,
+        target: 'segmentation-panel',
+      });
+    };
+
+    document.addEventListener(
+      'extensiondicomsegmentationsegloaded',
+      onSegmentationsLoaded
+    );
+
     return {
       menuOptions: [
         {
           icon: 'list',
           label: 'Segmentations',
           target: 'segmentation-panel',
+          stateEvent: SegmentationPanelTabUpdatedEvent,
           isDisabled: studies => {
             if (!studies) {
               return true;
diff --git a/extensions/dicom-segmentation/src/loadSegmentation.js b/extensions/dicom-segmentation/src/loadSegmentation.js
index a655c0687..e75ac1472 100644
--- a/extensions/dicom-segmentation/src/loadSegmentation.js
+++ b/extensions/dicom-segmentation/src/loadSegmentation.js
@@ -59,7 +59,16 @@ export default async function loadSegmentation(
    * without subscribing to external events.
    */
   console.log('Segmentation loaded.');
-  const event = new CustomEvent('extensiondicomsegmentationsegloaded');
+  const event = new CustomEvent('extensiondicomsegmentationsegloaded', {
+    detail: {
+      imageIds,
+      segDisplaySet,
+      labelmapBuffer,
+      segMetadata,
+      segmentsOnFrame,
+      labelmapSegments,
+    },
+  });
   document.dispatchEvent(event);
 
   return labelmapIndex;
diff --git a/platform/core/src/services/MeasurementService/MeasurementService.js b/platform/core/src/services/MeasurementService/MeasurementService.js
index a21ea8837..ce58cff9e 100644
--- a/platform/core/src/services/MeasurementService/MeasurementService.js
+++ b/platform/core/src/services/MeasurementService/MeasurementService.js
@@ -260,7 +260,6 @@ class MeasurementService {
     const sourceInfo = this._getSourceInfo(source);
 
     if (!definition) {
-      console.log('TEST');
       log.warn('No source definition provided. Exiting early.');
       return;
     }
diff --git a/platform/ui/src/components/roundedButtonGroup/RoundedButtonGroup.css b/platform/ui/src/components/roundedButtonGroup/RoundedButtonGroup.css
index 3bf03e5e0..f5d96fd97 100644
--- a/platform/ui/src/components/roundedButtonGroup/RoundedButtonGroup.css
+++ b/platform/ui/src/components/roundedButtonGroup/RoundedButtonGroup.css
@@ -4,6 +4,29 @@
   z-index: 0;
 }
 
+.RoundedButtonGroup .badgeNumber-container {
+  background-color: var(--ui-border-color-dark);
+  width: 21px;
+  height: 21px;
+  justify-content: center;
+  align-items: center;
+  display: flex;
+  border-radius: 50%;
+  font-size: 12px;
+  font-weight: bold;
+  bottom: 10px;
+  left: 5px;
+  color: white;
+  position: absolute;
+}
+
+.RoundedButtonGroup .badgeNumber {
+  font-size: 10px;
+  font-weight: bold;
+  display: block;
+  width: 25px;
+}
+
 .roundedButtonWrapper {
   cursor: pointer;
   display: inline-block;
@@ -36,7 +59,12 @@
   z-index: 1;
 }
 
-.roundedButtonWrapper .roundedButton svg .roundedButtonWrapper .roundedButton span {
+.roundedButtonWrapper
+  .roundedButton
+  svg
+  .roundedButtonWrapper
+  .roundedButton
+  span {
   margin: 0 2px;
 }
 
diff --git a/platform/ui/src/components/roundedButtonGroup/RoundedButtonGroup.js b/platform/ui/src/components/roundedButtonGroup/RoundedButtonGroup.js
index cd861f146..8c167df42 100644
--- a/platform/ui/src/components/roundedButtonGroup/RoundedButtonGroup.js
+++ b/platform/ui/src/components/roundedButtonGroup/RoundedButtonGroup.js
@@ -13,6 +13,7 @@ class RoundedButtonGroup extends Component {
       PropTypes.shape({
         value: PropTypes.any,
         label: PropTypes.string,
+        stateEvent: PropTypes.string,
         icon: PropTypes.oneOfType([
           PropTypes.string,
           PropTypes.shape({
@@ -30,6 +31,15 @@ class RoundedButtonGroup extends Component {
     value: null,
   };
 
+  state = {
+    badgeNumbers: [],
+  };
+
+  constructor() {
+    super();
+    this.onStateEvent = this.onStateEvent.bind(this);
+  }
+
   onClickOption = value => {
     let newValue = value;
     if (this.props.value === value) {
@@ -41,6 +51,48 @@ class RoundedButtonGroup extends Component {
     }
   };
 
+  onStateEvent(event) {
+    const optionIndex = this.props.options.findIndex(
+      o => o.value === event.detail.target
+    );
+    if (optionIndex > -1) {
+      const badgeNumbers = this.state.badgeNumbers;
+      badgeNumbers[optionIndex] = event.detail.badgeNumber;
+      this.setState({ badgeNumbers });
+    }
+  }
+
+  componentDidMount() {
+    this.props.options.forEach(option => {
+      if (option.stateEvent) {
+        document.addEventListener(option.stateEvent, this.onStateEvent);
+      }
+    });
+  }
+
+  componentDidUpdate(prevProps, prevState) {
+    this.props.options.forEach((option, index) => {
+      if (
+        option.stateEvent &&
+        option.stateEvent !==
+          (prevProps.options[index]
+            ? prevProps.options[index].stateEvent
+            : null)
+      ) {
+        document.removeEventListener(option.stateEvent, this.onStateEvent);
+        document.addEventListener(option.stateEvent, this.onStateEvent);
+      }
+    });
+  }
+
+  componentWillUnmount() {
+    this.props.options.forEach(option => {
+      if (option.stateEvent) {
+        document.removeEventListener(option.stateEvent, this.onStateEvent);
+      }
+    });
+  }
+
   render() {
     let className = classnames(
       RoundedButtonGroup.className,
@@ -62,6 +114,14 @@ class RoundedButtonGroup extends Component {
         <div className="bottomLabel">{option.bottomLabel}</div>
       );
 
+      let badgeNumber = this.state.badgeNumbers[index];
+      const badgeNumberOverflow = String(badgeNumber).length > 2;
+      badgeNumber = badgeNumber
+        ? badgeNumberOverflow
+          ? 99
+          : badgeNumber
+        : null;
+
       return (
         <div
           key={index}
@@ -70,6 +130,14 @@ class RoundedButtonGroup extends Component {
         >
           <div className="roundedButton">
             {optionText}
+            {badgeNumber && (
+              <div className="badgeNumber-container">
+                <span className="badgeNumber">
+                  {badgeNumber}
+                  {badgeNumberOverflow && '+'}
+                </span>
+              </div>
+            )}
             {iconProps && <Icon {...iconProps} />}
           </div>
           {bottomLabel}
diff --git a/platform/viewer/src/connectedComponents/ToolbarRow.js b/platform/viewer/src/connectedComponents/ToolbarRow.js
index 9d4745248..12acf31af 100644
--- a/platform/viewer/src/connectedComponents/ToolbarRow.js
+++ b/platform/viewer/src/connectedComponents/ToolbarRow.js
@@ -96,6 +96,8 @@ class ToolbarRow extends Component {
             value: menuOption.target,
             icon: menuOption.icon,
             bottomLabel: menuOption.label,
+            badgeNumber: menuOption.badgeNumber,
+            stateEvent: menuOption.stateEvent,
           };
           const from = menuOption.from || 'right';