1. Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
2. The Johns Hopkins University, Department of Mechanical Engineering, Whiting School of Engineering, Baltimore, MD 21218, USA
3. Laser Biomedical Research Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
4. Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
5. Department of Pathology, University Medical Center Utrecht Cancer Center, 3508 GA Utrecht, The Netherlands