Robert L. Duschka MD, Presenter: Nothing to Disclose

Peter Bischoff MD, Abstract Co-Author: Nothing to Disclose

Lüder C. Busch, Abstract Co-Author: Nothing to Disclose

Peter Hunold MD, Abstract Co-Author: Speaker, Bayer AG Speaker, General Electric Company Speaker, Siemens AG

Joerg Barkhausen MD, Abstract Co-Author: Research Consultant, Bayer AG

Florian M. Vogt, Abstract Co-Author: Nothing to Disclose

Digital x-ray tomosynthesis is a refinement of conventional geometric tomography delivering cross sectional images with high spatial resolution. Recently, the technique has successfully been established for breast imaging. Our study aimed to assess the potential of x-ray tomosynthesis for skeletal applications.

Five hands from donors who gave their bodies for medical education and research after death were examined. The specimens were placed on the detector in different positions ranging from 0° to 90° between the fingers and the direction of the x-ray tube movement. Thereafter the specimens were examined in the optimal orientation at 35 KV and a tube current ranging from 55 to 450 mAs, using an X-ray tube motion over an arc of up to ± 25°. Conventional two-dimensional hand-radiograph and high spatial resolution CT of the hands were performed to serve as standard of reference. Reconstructed images of the tomosynthesis studies were read by experienced radiologists to evaluate image quality and visibility of the joint margins, space and trabecular structure of the bone.

Up to 35 in-focus planes were generated during a single motion of the x-ray tube. All datasets could be acquired within 30s and images were reconstructed without loss of data. Each reconstructed image provided a matrix of 2500x1500 pixel requiring >7 MB disc space. The angle of hand-placement relating to the rotating x-ray tube significantly influences image quality. Images acquired parallel to the long axis delivered sharper borders of the bones and better visibility of the joint space. For the low dose scans image quality continuously improved with higher tube currents. However, for scans using >125 mAs there was no significant further improvement. Digital tomosynthesis provided better delineation of joint margin, space and trabecular structure compared to conventional radiographs and a higher spatial resolution compared to CT.

Digital tomosynthesis can obtain high quality cross sectional images of the hand within a very short acquisition time and with low radiation doses. Thus digital tomosynthesis seems to be an interesting and noteworthy imaging tool with the potential to assess different pathologies of the hands including trauma, arthritis and infections.

Tomosynthesis is a high-resolution image acquisition method may become an attractive and powerful alternative to CT for bone imaging.

Duschka, R, Bischoff, P, Busch, L, Hunold, P, Barkhausen, J, Vogt, F, Digital Tomosynthesis of the Hand: Old Wine in New Wineskins for Orthopaedic Applications?.  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9013808.html