code: function _removeCornerstoneEventListeners() {
    const cornerstone = external.cornerstone;
    const elementEnabledEvent = cornerstone.EVENTS.ELEMENT_ENABLED;
    const elementDisabledEvent = cornerstone.EVENTS.ELEMENT_DISABLED;
  
    cornerstone.events.removeEventListener(
      elementEnabledEvent,
      addEnabledElement
    );
    cornerstone.events.removeEventListener(
      elementDisabledEvent,
      removeEnabledElement
    );
  }
docs: Removes event listeners for the Cornerstone#ElementDisabled and
  Cornerstone#ElementEnabled events.
  @private
  @method
  @returns {void}