feat(ecg): add DICOM ECG waveform extension (#5856)

* feat(ecg): add DICOM ECG waveform extension

Introduce @ohif/extension-dicom-ecg for rendering DICOM waveform (ECG)
data. Register the extension in the basic mode and pluginConfig.json,
and remove ECG from NON_IMAGE_MODALITIES so waveform display sets are
handled by the new viewport.

* refactor(ecg): move ECG support into cornerstone extension per review feedback

- Remove standalone dicom-ecg extension; fold all ECG functionality into
  the cornerstone extension as requested by reviewer
- Add ECG SOP class handler (DicomEcgSopClassHandler) to the cornerstone
  extension getSopClassHandlerModule, registering ECG waveform metadata
  via genericMetadataProvider on display set creation
- Move ECG helpers (buildEcgModule, decodeInt16Multiplex, base64ToArrayBuffer)
  into extensions/cornerstone/src/utils/ecgMetadata.ts
- Handle ECGViewport in CornerstoneViewportService._setDisplaySets by
  detecting ECGViewport instanceof and calling setEcg(imageId) directly,
  so OHIFCornerstoneViewport can be used without a custom ECG viewport component
- Add ECG support to getCornerstoneViewportType utility
- Update basic mode to reference the cornerstone extension's ECG SOP handler
  and use the base cornerstone viewport for ECG display sets
- Migrate ecgMetadata and getCornerstoneViewportType tests

* chore: revert bun.lock to upstream origin/master

---------

Co-authored-by: Bill Wallace <wayfarer3130@gmail.com>

README.md

@@ -49,6 +49,7 @@ provided by the <a href="https://ohif.org/">Open Health Imaging Foundation (OHIF
 | <img src="https://github.com/OHIF/Viewers/blob/master/platform/docs/docs/assets/img/demo-4d.webp?raw=true" alt="4D" width="350"/> | 4D  | [Demo](https://viewer.ohif.org/dynamic-volume?StudyInstanceUIDs=2.25.232704420736447710317909004159492840763) |
 | <img src="https://github.com/OHIF/Viewers/blob/master/platform/docs/docs/assets/img/demo-video.webp?raw=true" alt="VIDEO" width="350"/> | Video  | [Demo](https://viewer.ohif.org/viewer?StudyInstanceUIDs=2.25.96975534054447904995905761963464388233) |
 | <img src="https://github.com/OHIF/Viewers/blob/master/platform/docs/docs/assets/img/microscopy.webp?raw=true" alt="microscopy" width="350"/> | Slide Microscopy  | [Demo](https://viewer.ohif.org/microscopy?StudyInstanceUIDs=2.25.141277760791347900862109212450152067508) |
+| <img src="https://github.com/OHIF/Viewers/blob/master/platform/docs/docs/assets/img/demo-ecg.webp?raw=true" alt="ECG" width="350"/> | ECG Waveform  | [Demo](https://viewer-dev.ohif.org/viewer?StudyInstanceUIDs=2.25.209974489360710696739324151261716440238) |
 
 ## About
 

extensions/cornerstone/src/getSopClassHandlerModule.js

@@ -3,6 +3,7 @@ import i18n from '@ohif/i18n';
 import { utilities as csUtils, Enums as csEnums } from '@cornerstonejs/core';
 import dcmjs from 'dcmjs';
 import { dicomWebUtils } from '@ohif/extension-default';
+import { buildEcgModule } from './utils/ecgMetadata';
 
 const { MetadataModules } = csEnums;
 const { utils } = OHIF;
@@ -155,6 +156,84 @@ export function getDicomMicroscopySopClassHandler({ servicesManager, extensionMa
   };
 }
 
-export function getSopClassHandlerModule(params) {
+/**
-  return [getDicomMicroscopySopClassHandler(params)];
+ * DICOM Waveform SOP Class UIDs for ECG / cardiac electrophysiology.
+ * Reference: https://dicom.nema.org/medical/dicom/current/output/chtml/part04/sect_B.5.html
+ */
+const ECG_SOP_CLASS_UIDS = {
+  TWELVE_LEAD_ECG_WAVEFORM_STORAGE: '1.2.840.10008.5.1.4.1.1.9.1.1',
+  GENERAL_ECG_WAVEFORM_STORAGE: '1.2.840.10008.5.1.4.1.1.9.1.2',
+  AMBULATORY_ECG_WAVEFORM_STORAGE: '1.2.840.10008.5.1.4.1.1.9.1.3',
+  HEMODYNAMIC_WAVEFORM_STORAGE: '1.2.840.10008.5.1.4.1.1.9.2.1',
+  CARDIAC_ELECTROPHYSIOLOGY_WAVEFORM_STORAGE: '1.2.840.10008.5.1.4.1.1.9.3.1',
+};
+
+const ecgSopClassUids = Object.values(ECG_SOP_CLASS_UIDS);
+
+const DicomEcgSOPClassHandlerId =
+  '@ohif/extension-cornerstone.sopClassHandlerModule.DicomEcgSopClassHandler';
+
+function _getEcgDisplaySetsFromSeries(instances, servicesManager) {
+  const { userAuthenticationService } = servicesManager.services;
+
+  return instances.map(instance => {
+    const { Modality, SOPInstanceUID } = instance;
+    const { SeriesDescription, SeriesNumber, SeriesDate } = instance;
+    const { SeriesInstanceUID, StudyInstanceUID, SOPClassUID } = instance;
+    const imageId = instance.imageId;
+
+    // Register ECG metadata in the OHIF metadata provider so that
+    // Cornerstone's ECGViewport can retrieve it via metaData.get('ecgModule', imageId).
+    if (imageId) {
+      const ecgModule = buildEcgModule(instance, userAuthenticationService);
+      if (ecgModule) {
+        csUtils.genericMetadataProvider.addRaw(imageId, {
+          type: MetadataModules.ECG,
+          metadata: ecgModule,
+        });
+      }
+    }
+
+    return {
+      Modality,
+      displaySetInstanceUID: utils.guid(),
+      SeriesDescription,
+      SeriesNumber,
+      SeriesDate,
+      SOPInstanceUID,
+      SeriesInstanceUID,
+      StudyInstanceUID,
+      SOPClassHandlerId: DicomEcgSOPClassHandlerId,
+      SOPClassUID,
+      referencedImages: null,
+      measurements: null,
+      viewportType: csEnums.ViewportType.ECG,
+      instances: [instance],
+      instance,
+      thumbnailSrc: null,
+      isDerivedDisplaySet: false,
+      isLoaded: false,
+      sopClassUids: ecgSopClassUids,
+      numImageFrames: 0,
+      numInstances: 1,
+      imageIds: imageId ? [imageId] : [],
+      supportsWindowLevel: false,
+      label: SeriesDescription || 'ECG',
+    };
+  });
+}
+
+export function getDicomEcgSopClassHandler({ servicesManager }) {
+  const getDisplaySetsFromSeries = instances =>
+    _getEcgDisplaySetsFromSeries(instances, servicesManager);
+
+  return {
+    name: 'DicomEcgSopClassHandler',
+    sopClassUids: ecgSopClassUids,
+    getDisplaySetsFromSeries,
+  };
+}
+
+export function getSopClassHandlerModule(params) {
+  return [getDicomMicroscopySopClassHandler(params), getDicomEcgSopClassHandler(params)];
 }

extensions/cornerstone/src/services/ViewportService/CornerstoneViewportService.ts

@@ -9,6 +9,7 @@ import {
   utilities as csUtils,
   VolumeViewport,
   VolumeViewport3D,
+  ECGViewport,
   cache,
   Enums as csEnums,
   BaseVolumeViewport,
@@ -778,6 +779,19 @@ class CornerstoneViewportService extends PubSubService implements IViewportServi
   /**
    * Sets the image data for the given viewport.
    */
+  private async _setEcgViewport(
+    viewport: Types.IECGViewport,
+    viewportData: StackViewportData
+  ): Promise<void> {
+    const [displaySet] = viewportData.data;
+    const imageId = displaySet.imageIds?.[0];
+    if (!imageId) {
+      console.error('[CornerstoneViewportService] ECG display set has no imageId');
+      return;
+    }
+    return viewport.setEcg(imageId);
+  }
+
   private async _setOtherViewport(
     viewport: Types.IStackViewport,
     viewportData: StackViewportData,
@@ -1257,6 +1271,10 @@ class CornerstoneViewportService extends PubSubService implements IViewportServi
       );
     }
 
+    if (viewport instanceof ECGViewport) {
+      return this._setEcgViewport(viewport as unknown as Types.IECGViewport, viewportData as StackViewportData);
+    }
+
     return this._setOtherViewport(
       viewport,
       viewportData as StackViewportData,

extensions/cornerstone/src/utils/ecgMetadata.test.ts

@@ -0,0 +1,217 @@
+import { decodeInt16Multiplex, base64ToArrayBuffer, buildEcgModule } from './ecgMetadata';
+
+// ---------------------------------------------------------------------------
+// decodeInt16Multiplex
+// ---------------------------------------------------------------------------
+describe('decodeInt16Multiplex', () => {
+  it('demultiplexes 2 channels correctly', () => {
+    // Interleaved layout: [ch0_s0, ch1_s0, ch0_s1, ch1_s1, ch0_s2, ch1_s2]
+    const interleaved = new Int16Array([10, 20, 30, 40, 50, 60]);
+    const channels = decodeInt16Multiplex(interleaved.buffer, 2, 3);
+
+    expect(channels).toHaveLength(2);
+    expect(Array.from(channels[0])).toEqual([10, 30, 50]);
+    expect(Array.from(channels[1])).toEqual([20, 40, 60]);
+  });
+
+  it('handles a single channel', () => {
+    const data = new Int16Array([100, 200, 300]);
+    const channels = decodeInt16Multiplex(data.buffer, 1, 3);
+
+    expect(channels).toHaveLength(1);
+    expect(Array.from(channels[0])).toEqual([100, 200, 300]);
+  });
+
+  it('handles negative values (signed short)', () => {
+    const data = new Int16Array([-1000, -2000, -3000]);
+    const channels = decodeInt16Multiplex(data.buffer, 1, 3);
+
+    expect(Array.from(channels[0])).toEqual([-1000, -2000, -3000]);
+  });
+
+  it('returns empty arrays when numberOfChannels or numberOfSamples is 0', () => {
+    const emptyBuffer = new Int16Array([]).buffer;
+
+    expect(decodeInt16Multiplex(emptyBuffer, 0, 0)).toHaveLength(0);
+    expect(decodeInt16Multiplex(emptyBuffer, 0, 10)).toHaveLength(0);
+  });
+
+  it('produces Int16Array instances for each channel', () => {
+    const data = new Int16Array([1, 2]);
+    const channels = decodeInt16Multiplex(data.buffer, 2, 1);
+
+    expect(channels[0]).toBeInstanceOf(Int16Array);
+    expect(channels[1]).toBeInstanceOf(Int16Array);
+  });
+});
+
+// ---------------------------------------------------------------------------
+// base64ToArrayBuffer
+// ---------------------------------------------------------------------------
+describe('base64ToArrayBuffer', () => {
+  it('decodes a simple base64 string to the correct bytes', () => {
+    // "ABC" in ASCII = [65, 66, 67]; base64 of that is 'QUJD'
+    const buffer = base64ToArrayBuffer('QUJD');
+    const bytes = new Uint8Array(buffer);
+
+    expect(bytes).toHaveLength(3);
+    expect(Array.from(bytes)).toEqual([65, 66, 67]);
+  });
+
+  it('round-trips an Int16Array through base64', () => {
+    const original = new Int16Array([500, -300, 0, 32767]);
+    const base64 = btoa(String.fromCharCode(...new Uint8Array(original.buffer)));
+    const recovered = new Int16Array(base64ToArrayBuffer(base64));
+
+    expect(Array.from(recovered)).toEqual(Array.from(original));
+  });
+
+  it('returns an ArrayBuffer', () => {
+    const result = base64ToArrayBuffer('AA=='); // single zero byte
+    expect(result).toBeInstanceOf(ArrayBuffer);
+    expect(result.byteLength).toBe(1);
+  });
+});
+
+// ---------------------------------------------------------------------------
+// buildEcgModule
+// ---------------------------------------------------------------------------
+describe('buildEcgModule', () => {
+  const makeInstance = (overrides = {}) => ({
+    WaveformSequence: [
+      {
+        NumberOfWaveformChannels: 12,
+        NumberOfWaveformSamples: 5000,
+        SamplingFrequency: 500,
+        WaveformBitsAllocated: 16,
+        WaveformSampleInterpretation: 'SS',
+        MultiplexGroupLabel: '12 Lead ECG',
+        ChannelDefinitionSequence: [
+          { ChannelSourceSequence: [{ CodeMeaning: 'Lead I' }] },
+          { ChannelSourceSequence: [{ CodeMeaning: 'Lead II' }] },
+        ],
+        WaveformData: { InlineBinary: btoa('\x00\x01') },
+      },
+    ],
+    ...overrides,
+  });
+
+  it('returns null when WaveformSequence is absent', () => {
+    expect(buildEcgModule({})).toBeNull();
+    expect(buildEcgModule({ WaveformSequence: [] })).toBeNull();
+  });
+
+  it('returns a valid ecgModule for a complete instance', () => {
+    const module = buildEcgModule(makeInstance());
+
+    expect(module).not.toBeNull();
+    expect(module!.numberOfWaveformChannels).toBe(12);
+    expect(module!.numberOfWaveformSamples).toBe(5000);
+    expect(module!.samplingFrequency).toBe(500);
+    expect(module!.waveformBitsAllocated).toBe(16);
+    expect(module!.waveformSampleInterpretation).toBe('SS');
+    expect(module!.multiplexGroupLabel).toBe('12 Lead ECG');
+    expect(module!.channelDefinitionSequence).toHaveLength(2);
+    expect(module!.channelDefinitionSequence[0].channelSourceSequence.codeMeaning).toBe('Lead I');
+    expect(typeof module!.waveformData.retrieveBulkData).toBe('function');
+  });
+
+  it('applies defaults for missing optional fields', () => {
+    const instance = {
+      WaveformSequence: [
+        {
+          // No explicit values — all defaults
+          WaveformData: { InlineBinary: btoa('\x00\x00') },
+        },
+      ],
+    };
+    const module = buildEcgModule(instance);
+
+    expect(module!.numberOfWaveformChannels).toBe(0);
+    expect(module!.numberOfWaveformSamples).toBe(0);
+    expect(module!.samplingFrequency).toBe(1);
+    expect(module!.waveformBitsAllocated).toBe(16);
+    expect(module!.waveformSampleInterpretation).toBe('SS');
+    expect(module!.multiplexGroupLabel).toBe('');
+    expect(module!.channelDefinitionSequence).toHaveLength(0);
+  });
+
+  it('retrieveBulkData decodes InlineBinary data correctly', async () => {
+    const samples = new Int16Array([10, 20, 30]);
+    const base64 = btoa(String.fromCharCode(...new Uint8Array(samples.buffer)));
+
+    const instance = {
+      WaveformSequence: [
+        {
+          NumberOfWaveformChannels: 1,
+          NumberOfWaveformSamples: 3,
+          WaveformData: { InlineBinary: base64 },
+        },
+      ],
+    };
+
+    const module = buildEcgModule(instance);
+    const channels = await module!.waveformData.retrieveBulkData();
+
+    expect(channels).toHaveLength(1);
+    expect(Array.from(channels[0])).toEqual([10, 20, 30]);
+  });
+
+  it('retrieveBulkData returns [] when WaveformData is absent', async () => {
+    const instance = {
+      WaveformSequence: [
+        { NumberOfWaveformChannels: 1, NumberOfWaveformSamples: 1 },
+      ],
+    };
+    const module = buildEcgModule(instance);
+    const channels = await module!.waveformData.retrieveBulkData();
+
+    expect(channels).toEqual([]);
+  });
+
+  it('retrieveBulkData fetches BulkDataURI with auth header when provided', async () => {
+    const samples = new Int16Array([1, 2]);
+    global.fetch = jest.fn().mockResolvedValue({
+      ok: true,
+      arrayBuffer: () => Promise.resolve(samples.buffer),
+    });
+
+    const userAuthenticationService = {
+      getAuthorizationHeader: () => ({ Authorization: 'Bearer token123' }),
+    };
+    const instance = {
+      WaveformSequence: [
+        {
+          NumberOfWaveformChannels: 1,
+          NumberOfWaveformSamples: 2,
+          WaveformData: { BulkDataURI: 'http://example.com/waveform' },
+        },
+      ],
+    };
+
+    const module = buildEcgModule(instance, userAuthenticationService);
+    await module!.waveformData.retrieveBulkData();
+
+    expect(global.fetch).toHaveBeenCalledWith('http://example.com/waveform', {
+      headers: {
+        Accept: 'application/octet-stream',
+        Authorization: 'Bearer token123',
+      },
+    });
+  });
+
+  it('retrieveBulkData throws when BulkDataURI response is not ok', async () => {
+    global.fetch = jest.fn().mockResolvedValue({ ok: false, status: 403 });
+
+    const instance = {
+      WaveformSequence: [
+        {
+          WaveformData: { BulkDataURI: 'http://example.com/waveform' },
+        },
+      ],
+    };
+
+    const module = buildEcgModule(instance);
+    await expect(module!.waveformData.retrieveBulkData()).rejects.toThrow('403');
+  });
+});

extensions/cornerstone/src/utils/ecgMetadata.ts

@@ -0,0 +1,129 @@
+/**
+ * Decode a multiplexed Int16 buffer into per-channel arrays.
+ * Layout: sample0ch0, sample0ch1 ... sample0chN, sample1ch0, …
+ * Note: DICOM ECG data is canonically SS (signed short). The sampleInterpretation
+ * field is forwarded to ECGViewport for its own use; the raw buffer is always
+ * treated as Int16 because Cornerstone ECGViewport expects Int16Array[].
+ */
+export function decodeInt16Multiplex(
+  buffer: ArrayBuffer,
+  numberOfChannels: number,
+  numberOfSamples: number
+): Int16Array[] {
+  const src = new Int16Array(buffer);
+  const channels: Int16Array[] = [];
+  for (let ch = 0; ch < numberOfChannels; ch++) {
+    const out = new Int16Array(numberOfSamples);
+    for (let s = 0; s < numberOfSamples; s++) {
+      out[s] = src[s * numberOfChannels + ch];
+    }
+    channels.push(out);
+  }
+  return channels;
+}
+
+/**
+ * Decode a base64 InlineBinary string into a raw ArrayBuffer.
+ */
+export function base64ToArrayBuffer(base64: string): ArrayBuffer {
+  const binaryStr = atob(base64);
+  const bytes = new Uint8Array(binaryStr.length);
+  for (let i = 0; i < binaryStr.length; i++) {
+    bytes[i] = binaryStr.charCodeAt(i);
+  }
+  return bytes.buffer;
+}
+
+export type EcgModule = {
+  numberOfWaveformChannels: number;
+  numberOfWaveformSamples: number;
+  samplingFrequency: number;
+  waveformBitsAllocated: number;
+  waveformSampleInterpretation: string;
+  multiplexGroupLabel: string;
+  channelDefinitionSequence: Array<{ channelSourceSequence: { codeMeaning: string } }>;
+  waveformData: { retrieveBulkData: () => Promise<Int16Array[]> };
+};
+
+/**
+ * Parse the naturalized DICOM instance's WaveformSequence and build the ecgModule
+ * that Cornerstone's ECGViewport.setEcg() expects via
+ * metaData.get(MetadataModules.ECG, imageId).
+ *
+ * Returns null if the instance has no WaveformSequence.
+ */
+export function buildEcgModule(
+  instance: any,
+  userAuthenticationService?: any
+): EcgModule | null {
+  const waveformGroups = instance?.WaveformSequence;
+  if (!waveformGroups?.length) {
+    return null;
+  }
+
+  // Use the first (and typically only) multiplex group
+  const group = waveformGroups[0];
+
+  const numberOfChannels = group.NumberOfWaveformChannels ?? 0;
+  const numberOfSamples = group.NumberOfWaveformSamples ?? 0;
+  const samplingFrequency = group.SamplingFrequency ?? 1;
+  const bitsAllocated = group.WaveformBitsAllocated ?? 16;
+  const sampleInterpretation = group.WaveformSampleInterpretation ?? 'SS';
+  const multiplexGroupLabel = group.MultiplexGroupLabel ?? '';
+
+  const channelDefinitionSequence = (group.ChannelDefinitionSequence ?? []).map(ch => ({
+    channelSourceSequence: {
+      codeMeaning:
+        ch?.ChannelSourceSequence?.[0]?.CodeMeaning ??
+        ch?.ChannelSourceSequence?.[0]?.codeMeaning ??
+        '',
+    },
+  }));
+
+  const retrieveBulkData = async (): Promise<Int16Array[]> => {
+    const waveformData = group.WaveformData;
+
+    if (!waveformData) {
+      console.warn('[ECGViewport] No WaveformData found on instance');
+      return [];
+    }
+
+    let buffer: ArrayBuffer;
+
+    if (waveformData.InlineBinary) {
+      buffer = base64ToArrayBuffer(waveformData.InlineBinary);
+    } else if (waveformData.BulkDataURI) {
+      const headers: Record<string, string> = {
+        Accept: 'application/octet-stream',
+      };
+      const authHeader = userAuthenticationService?.getAuthorizationHeader?.();
+      if (authHeader) {
+        Object.assign(headers, authHeader);
+      }
+
+      const response = await fetch(waveformData.BulkDataURI, { headers });
+      if (!response.ok) {
+        throw new Error(
+          `[ECGViewport] Failed to fetch waveform BulkDataURI: ${response.status}`
+        );
+      }
+      buffer = await response.arrayBuffer();
+    } else {
+      console.warn('[ECGViewport] WaveformData has no InlineBinary or BulkDataURI');
+      return [];
+    }
+
+    return decodeInt16Multiplex(buffer, numberOfChannels, numberOfSamples);
+  };
+
+  return {
+    numberOfWaveformChannels: numberOfChannels,
+    numberOfWaveformSamples: numberOfSamples,
+    samplingFrequency,
+    waveformBitsAllocated: bitsAllocated,
+    waveformSampleInterpretation: sampleInterpretation,
+    multiplexGroupLabel,
+    channelDefinitionSequence,
+    waveformData: { retrieveBulkData },
+  };
+}

extensions/cornerstone/src/utils/getCornerstoneViewportType.test.ts

@@ -10,6 +10,7 @@ jest.mock('@cornerstonejs/core', () => ({
       WHOLE_SLIDE: 'wholeslide',
       ORTHOGRAPHIC: 'orthographic',
       VOLUME_3D: 'volume3d',
+      ECG: 'ecg',
     },
   },
 }));
@@ -50,9 +51,14 @@ describe('getCornerstoneViewportType', () => {
     expect(result).toBe(Enums.ViewportType.VOLUME_3D);
   });
 
+  it('should return ECG when viewportType is ecg', () => {
+    const result = getCornerstoneViewportType('ecg');
+    expect(result).toBe(Enums.ViewportType.ECG);
+  });
+
   it('should throw error for invalid viewport type', () => {
     expect(() => getCornerstoneViewportType('invalid')).toThrow(
-      'Invalid viewport type: invalid. Valid types are: stack, volume, video, wholeslide'
+      'Invalid viewport type: invalid. Valid types are: stack, volume, video, wholeslide, ecg'
     );
   });
 

extensions/cornerstone/src/utils/getCornerstoneViewportType.ts

@@ -7,6 +7,7 @@ const ORTHOGRAPHIC = 'orthographic';
 const VOLUME_3D = 'volume3d';
 const VIDEO = 'video';
 const WHOLESLIDE = 'wholeslide';
+const ECG = 'ecg';
 
 export default function getCornerstoneViewportType(
   viewportType: string,
@@ -25,6 +26,10 @@ export default function getCornerstoneViewportType(
     return Enums.ViewportType.WHOLE_SLIDE;
   }
 
+  if (lowerViewportType === ECG) {
+    return Enums.ViewportType.ECG;
+  }
+
   if (lowerViewportType === VOLUME || lowerViewportType === ORTHOGRAPHIC) {
     return Enums.ViewportType.ORTHOGRAPHIC;
   }
@@ -34,6 +39,6 @@ export default function getCornerstoneViewportType(
   }
 
   throw new Error(
-    `Invalid viewport type: ${viewportType}. Valid types are: stack, volume, video, wholeslide`
+    `Invalid viewport type: ${viewportType}. Valid types are: stack, volume, video, wholeslide, ecg`
   );
 }

modes/basic/src/index.tsx

@@ -15,7 +15,7 @@ const { structuredCloneWithFunctions } = utils;
  * This list used to include SM, for whole slide imaging, but this is now supported
  * by cornerstone.  Others of these may get added.
  */
-export const NON_IMAGE_MODALITIES = ['ECG', 'SEG', 'RTSTRUCT', 'RTPLAN', 'PR', 'SR'];
+export const NON_IMAGE_MODALITIES = ['SEG', 'RTSTRUCT', 'RTPLAN', 'PR', 'SR'];
 
 export const ohif = {
   layout: '@ohif/extension-default.layoutTemplateModule.viewerLayout',
@@ -47,6 +47,10 @@ export const dicomvideo = {
   viewport: '@ohif/extension-dicom-video.viewportModule.dicom-video',
 };
 
+export const dicomecg = {
+  sopClassHandler: '@ohif/extension-cornerstone.sopClassHandlerModule.DicomEcgSopClassHandler',
+};
+
 export const dicompdf = {
   sopClassHandler: '@ohif/extension-dicom-pdf.sopClassHandlerModule.dicom-pdf',
   viewport: '@ohif/extension-dicom-pdf.viewportModule.dicom-pdf',
@@ -86,6 +90,7 @@ export const extensionDependencies = {
 
 export const sopClassHandlers = [
   dicomvideo.sopClassHandler,
+  dicomecg.sopClassHandler,
   dicomSeg.sopClassHandler,
   dicomPmap.sopClassHandler,
   ohif.sopClassHandler,
@@ -291,6 +296,7 @@ export const basicLayout = {
           ohif.sopClassHandler,
           dicomvideo.sopClassHandler,
           ohif.wsiSopClassHandler,
+          dicomecg.sopClassHandler,
         ],
       },
       {