Configuring the Hanging List

A hanging list is used to structure all the different cases and images within a reader study. The list specifies which images group to create the cases, and in which order the cases are to be presented. The cases, which are essentially an ordered list of images, are then used to link each study answer to one or more images. A hanging list hence specifies which images are visible when the questions are answered. It also entails that if you substantially update the hanging list, the new cases and previously given answers might not match up as you'd expect.

The default hanging list that is created automatically for you will create a single-image case for each image, pinning each of the images to the main view port. This could be perfectly fine for your study, but if you want to add a multiple images, or a mask/overlay per page the hanging list needs to be updated.

The hanging list can be accessed through your reader study: Information → Update Settings. Here you see all the cases with the matching images.


If you change "Tree" to "Code" in the drop-down menu in the header, you can easily edit the hanging list to your liking. The schema is quite straight forward: a JSON formatted list, with objects that tell which view port should show which image. Some examples are given below. Note that the image IDs are added to the hanging list automatically when you upload images. These IDs are equal to the filenames when the images were uploaded.

Simple Hanging List

By default, the simplest hanging list is generated: one image per case. For two images and two cases the hanging list and resulting page:

[
  {
    "main": "image1.mha"
  },
  {
    "main": "image2.mha"
  }
]

Side-by-side hanging

You can also have two images for once case, resulting in two images being shown on one page. The following hanging shows two pages with two images side by side on each page:

[
  {
    "main": "image1.dcm",
    "secondary": "image2.dcm"
  },
  {
    "main": "image3.dcm",
    "secondary": "image4.dcm"
  }
]

Hanging Lists with overlays

You can designate an image as an overlay on any viewport. The following shows a single page which has three side by side, with the last one having an overlay:

[
  {
    "main": "image1.dcm",
    "secondary": "image2.dcm",
    "tertiary": "image3.dcm",
    "teriary-overlay": "image3_mask.dcm"     
 }
]

Hanging lists to page

A hanging lists will not always result in the exact same page being generated in the default CIRRUS viewer. The hanging list is only the seed for how the page is build up, other factors are taken into consideration as well that determine which page layout is chosen:

  • How many images are being shown? (Up to denary/10 view-ports are currently supported)
  • Are the images two, three or four dimensional? (Above examples were 3D)
  • What is the type of the image, how large is it? (Pathology TIFFS are differently layout)
  • What is the configured image logic. (This determines how above and other factors should weigh in-to the final layout)