Low Dose CT Metastases Image and Projection Data

Lack of access to projection data from patient CT scans is a major limitation for development and validation of new reconstruction algorithms. To meet this critical need, we are building a library of CT patient projection data in an open and vendor-neutral format, DICOM-CT-PD, which is an extended DICOM format that contains sinogram data, acquisition geometry, patient information, and pathology identification. The library consists of scans of various types, including head scans, chest scans, abdomen scans, electrocardiogram (ECG)-gated scans, and dual-energy scans. For each scan, three types of data are provided, including DICOM-CT-PD projection data at various dose levels, reconstructed CT images, and a free-form text file. Several instructional documents are provided to help the users extract information from DICOM-CT-PD files, including a dictionary file for the DICOM-CT-PD format, a DICOM-CT-PD reader, and a user manual. Radiologist detection performance based on the reconstructed CT images is also provided. So far 328 head cases, 228 chest cases, and 228 abdomen cases have been collected for potential inclusion. The final library will include a selection of 50 head, chest, and abdomen scans each from at least two different manufacturers, and a few ECG-gated scans and dual-source, dual-energy scans. It will be freely available to academic researchers, and is expected to greatly facilitate the development and validation of CT reconstruction algorithms.

Projection data from patient CT scans, especially those with known pathology, are essential to the development and validation of new reconstruction algorithms. However, the patient projection data collected from commercial CT scanners are proprietary, which means researchers need research agreements with CT vendors to access the data; the projection data collected from commercial CT scanners are also vendor-specific, which means each CT vendor stores the projection data in its own format (the geometries used to store the projection images and the acquisition parameters, the unit used to store the acquisition parameters, and the precision and range of the numerical values might all differ from vendor to vendor).

To allow more researchers to access patient CT projection data with minimum efforts, a library of CT patient projection data is being built and will be freely available to academic researchers. The projection data in the library were decoded from commercial CT scans, and have been converted into an open and standard format.

Acknowledgements

We would like to acknowledge the individuals and institutions that have provided data for this collection:

• Hospital/Institution Name city, state, country - Special thanks to First Last Names, degree PhD, MD, etc from the Department of xxxxxx, Additional Names from same location.

• Continue with any names from additional submitting sites if collection consists of more that one.