These links help describe how to use the .XML annotation files which are packaged along with the images in the The Cancer Imaging Archive. The option to include annotation files in the download is enabled by default, so the XML described here will be included when downloading the LIDC-IDRI images unless you specifically uncheck this option. Please note that it is not currently possible to visualize this annotation and markup on top of the images themselves. The Cancer Imaging Program is exploring the possibility of converting this XML into AIM format so that it could be visualized in AIM compatible workstations, but no definite plans are in place at this time. If you are only interested in the XML files or you have already downloaded the images you can obtain them here:
The following documentation explains the format and other relevant information about the XML annotation and markup files:
- XML File Documentation
- XML Base Schema - This file is called "voi array.xsd", and is central in defining tumors greater than or equal 3 mm in the datasets as well as defining the loci of non-nodules.
- Annotated XML File
- LIDC Radiologist Instructions for Spatial Location and Extent Estimates
Annotation and Markup Issues/Comments
- Please note that it is not currently possible to visualize this annotation and markup on top of the images themselves. The Cancer Imaging Program is exploring the possibility of converting this XML into a standardized format so that it could be visualized in commonly available workstations, but no definite estimate of completion is available at this time.
- For a subset of approximately 100 cases from among the initial 399 cases released, inconsistent rating systems were used among the 5 sites with regard to the spiculation and lobulation characteristics of lesions identified as nodules > 3 mm. The XML nodule characteristics data as it exists for some cases will be impacted by this error. We apologize for any inconvenience.
- Also note that the XML files do not store radiologist annotations in a manner that allows for a comparison of individual radiologist reads across cases (i.e., the first reader recorded in the XML file of one CT scan will not necessarily be the same radiologist as the first reader recorded in the XML file of another CT scan).
- March 2010: Contrary to previous documentation, the correct ordering for the subjective nodule lobulation and nodule spiculation rating scales stored in the XML files is 1=none to 5=marked. The issue of consistency noted in issue 1 still remains to be corrected.
- Note: On 2012-03-21 the XML associated with patient LIDC-IDRI-0101 was updated with a corrected version of the file.
Nodule Size List
This link provides a list of available cases and the associated size of each identified nodule.