James T. Dobbins III
Associate Professor (primary appt: Radiology, Medical Physics Graduate Program)
- Office Location: 2424 Erwin Road, Suite 302
- Email Address:
- Web Page:
|Ph.D.||University of Wisconsin at Madison||1985|
There are several research projects underway in my laboratory, focusing on the improvement of diagnostic accuracy in digital chest radiography and digital mammography. The first project uses a dual-energy digital radiography technique that forms images which have either the bones or soft-tissues canceled. By eliminating the ribs in the soft-tissue image, better accuracy in detecting nodules has been demonstrated in early clinical evaluations of the technique. The bone image is also useful in that it demonstrates whether a detected nodule is calcified, at a fraction of the cost and radiation exposure of sending the patient to CT. We have received six years of NIH grant funding to develop a practical screening method for nodular disease using the dual-energy technique. A second major area of research is digital tomosynthesis. This technique allows longitudinal slice images of a patient to be generated from a series of projection images taken at different angles. We are evaluating this technique for its potential to improve detection of pulmonary nodules. We have received seven years of NIH funding to develop and evaluate this technique. Preliminary evaluation in a pilot study using human subjects revealed that the detection rate for pulmonary nodules increased from about 22% to 70% in tomosynthesis slice images compared with conventional PA chest radiographs. Thus, the tomosynthesis technique would appear to hold promise as a method of improving both sensitivity and specificity of pulmonary nodule detection in vivo. We are also expanding this tomosynthesis work to evaluate its potential for improving detection of masses and calcifications in digital mammograms. Other projects include theoretical analysis of digital imaging performance and the measurement of image quality (DQE) in computed radiography and flat-panel systems.
- MEDPHY 731.01 - ADV MED IMAGING PHYSICS
Representative Publications: (More Publications)
- Dobbins, J.T. and Samei, E. and Ranger, N.T. and Ying Chen, Intercomparison of methods for image quality characterization. II. Noise power spectrum, Med. Phys. (USA), vol 33 no. 5 (2006), pp. 1466 - 75 [1.2188819] [abs].
- Godfrey, D.J. and McAdams, H.P. and Dobbins, J.T., III, Optimization of the matrix inversion tomosynthesis (MITS) impulse response and modulation transfer function characteristics for chest imaging, Med. Phys. (USA), vol 33 no. 3 (2006), pp. 655 - 67 [1.2170398] [abs].
- Dobbins, J.T., III and Godfrey, D.J., Digital x-ray tomosynthesis: current state of the art and clinical potential, Phys. Med. Biol. (UK), vol 48 no. 19 (2003), pp. 65 - 106 [R01] [abs].
- Warp, R.J. and Dobbins, J.T., III, Quantitative evaluation of noise reduction strategies in dual-energy imaging, Med. Phys. (USA), vol 30 no. 2 (2003), pp. 190 - 8 [1.1538232] [abs].
- Dobbins, J.T., III and Ergunb, D.L. and Rutz, L. and Hinshaw, D.A. and Blume, H. and Clark, D.C., DQE(f) of four generations of computed radiography acquisition devices, Med. Phys. (USA), vol 22 no. 10 (1995), pp. 1581 - 93 [1.597627] [abs].
Lectures and Invited Talks:
- Theoretical and practical elements of tomosynthesis imaging (invited workshop), SPIE Physics of Medical Imaging Conference,
- Imaging in Medicine: digital radiography (keynote address), SPIE Physics of Medical Imaging Conference,
- Digital radiography: technical foundations and contemporary research, Memphis BioImaging Symposium,
- Advances in digital radiography -- Digital radiographic advanced methods for depth discrimination: chest tomosynthesis, Radiological Society of North America 91st Scientific Assembly,
- Digital x-ray detectors for radiography: technical innovations (physics plenary talk), Radiological Society of North America 85th Scientific Assembly,
- Founder and Director, Duke Medical Physics Graduate Program,
- Co-founder and co-chair, Steering Committee for the Society of Directors of Academic Medical Physics Programs,
- Co-chair, SPIE Physics of Medical Imaging Conference,
- Chair, NIH Special Study Section 7,
- Associate Editor, Medical Physics journal,