IDC Viewer is based on the open-source Open Health Imaging Foundation (OHIF) Viewer, with some minor customizations that are implemented in the IDC fork of the OHIF Viewer in GitHub. IDC Viewer is opened every time you click the "eye" icon in the study or series table of the IDC Portal.
IDC Viewer is a "zero-footprint" client-side viewer. What this means is that before you can see the image in the viewer, it has to be downloaded to your browser from the IDC DICOM stores. IDC Viewer communicates the data it receives through a proxy via the DICOMweb interface implemented in GCP Cloud Healthcare API. The proxy is intended to throttle download of data.
Depending on a variety of factors (size of the image, your network connection, responsiveness of the proxy) the process of loading images into your browser can take some time before the entire image series is loaded. You will know the series is not loaded completely if you cannot scroll to the arbitrary location of the image volume. If you want to ensure the entire series is loaded before you start to explore the reconstructed volume, you can
toggle CINE mode and wait until the cine loop is proceeding smoothly through the entire set of slices, or
toggle 2D Multi-planar Reconstruction (MPR) and wait until reconstructed planes are fully populated.
CINE and 2D MPR modes are shown with red and yellow arrows in the image below, respectively.
Note that 2D MPR mode is only available for series that form a consistent volume (that is, all pixel spacings equal, slices equally spaced, and so on, which means you will not see the MPR button for such series as time-resolved MRI, as an example).
The main functions of the viewer are available via the toolbar controls shown below.
The functionality supported by those tools should be self-explanatory, or can be discovered via quick experimentation.
IDC Viewer supports visualization of DICOM Segmentation objects (SEG) and DICOM Radiotherapy Structure Sets (RTSTRUCT). When available in a given study, you will see those modalities labeled as such in the left-hand panel of the viewer, as shown below. To see a specific SEG or RTSTRUCT, drag the thumbnail to the viewer. After that you can open the RTSTRUCT/SEG panel in the upper right corner to jump to the locations of the specific structure sets or segments, and to control their individual visibility.
Below is an example of series objects that are not viewable at the series level.
You can use IDC Viewer to visualize any of the suitable data in IDC. To configure the IDC Viewer URL, simply append
StudyInstanceUID of a study available in IDC to the following prefix: https://viewer.imaging.datacommons.cancer.gov/viewer/. This will open the entire study in the viewer. You can also configure the URL to open specific series of the study, as defined by the list of
SeriesInstanceUID items. When you open the IDC Viewer from the IDC Portal, the URLs of the pages will be populated following those conventions.
Here are some specific examples, taken from the IDC Portal dashboard:
open entire study with the
open the specified subset of series from the study above: https://viewer.imaging.datacommons.cancer.gov/viewer/184.108.40.206.4.1.145220.127.116.11.6279.6001.224985459390356936417021464571?seriesInstanceUID=1.2.276.0.7230010.3.1.3.0.57823.1553343864.578877,18.104.22.168.4.1.14522.214.171.124.6279.6001.273525289046256012743471155680
You can share the viewer URLs if you want to refer to visualizations of the specific items from IDC. You can also use this functionality if you want to visualize specific items from your notebook or a custom dashboard (e.g., a Google DataStudio dashboard).