Hypofractionated high dose radiation therapy is an increasingly important treatment approach. Image guidance is imperative to ensure accurate patient positioning and to allow the use of tight treatment margin for high dose delivery. At present, the prevailing guidance method employs x- ray imaging to provide 3D volumetric and/or 2D projection information. Unfortunately, the approach is found wanting for tumors at low radiographic contrast with the surrounding tissue. These include important abdominal sites such as prostate, pancreas and liver. Consequently, detection of implanted markers has been employed as an alternative. However, these surrogates are also less than ideal due to the lack of anatomic information and the invasive nature of the procedure. In response to PAR10-169, an academic-industrial partnership is formed between Johns Hopkins University (JHU), Elekta-Resonant and Cleveland Clinic (CC), to develop an integrated 3D x-ray/ultrasound imaging system to provide on-board guidance for hypofractionated radiation therapy. The partnership has significant expertise in x-ray and ultrasound imaging, robotic engineering and radiation therapy. We have 3 specific aims.
Specific Aim 1 is to design and construct the system. A 3D ultrasound imaging system will be docked onto a medical accelerator equipped with on-board x-ray cone-beam CT (CBCT) imaging. Ultrasound imaging overcomes the hurdle of detecting low contrast soft tissue target with x-ray imaging, while CBCT provides the anatomic information for setting up the patient in the machine frame of reference and for dose re-calculation if necessary. Robotic control with force sensors will be employed to automate the positioning of the ultrasound system which will remain on the patient throughout the treatment session to provide real-time monitoring. The procedure is non-invasive. The monitoring is non-ionizing and desirable for applications with pediatric patients.
Specific Aim 2 focuses on optimizing the IGRT workflow for planning, radiation delivery to avoid the interference of imaging and irradiation procedures with each other.
For Specific Aim 3, we will validate the performance of the integrated imaging system at JHU and CC. We will test the hypothesis that guidance using the integrated robotic system is superior to CBCT or ultrasound imaging alone by demonstrating that the target definition is more reproducible and less user-dependent. The expertise of partners is well suited to fulfill the expectations of PAR10-169. Two commercial grade systems will be constructed. JHU and CC represent the end-users to conduct in-field validation of these systems. Elekta-Resonant is also an ideal industrial partner to pursue commercialization for dissemination in the community.

Public Health Relevance

The novel integration of x-ray and ultrasound 3D imaging allows localization of targets that are difficult to detect radiographically while providing volumetric anatomic information. The implementation of the capability on-board a medical accelerator ensures accurate irradiation of tumors in the abdominal region, and is particularly vital for high dose short course radiation treatment. Our academic-industrial partnership is well suited for developing the system and promoting its dissemination in the community.

National Institute of Health (NIH)
National Cancer Institute (NCI)
Research Project (R01)
Project #
Application #
Study Section
Special Emphasis Panel (ZRG1-SBIB-U (55))
Program Officer
Deye, James
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Johns Hopkins University
Schools of Medicine
United States
Zip Code
Su, Lin; Iordachita, Iulian; Zhang, Yin et al. (2017) Feasibility study of ultrasound imaging for stereotactic body radiation therapy with active breathing coordinator in pancreatic cancer. J Appl Clin Med Phys 18:84-96
?en, H Tutkun; Lediju Bell, Muyinatu A; Zhang, Yin et al. (2015) System Integration and Preliminary In-Vivo Experiments of a Robot for Ultrasound Guidance and Monitoring during Radiotherapy. Proc Int Conf Adv Robot 2015:53-59
Zhong, Yahua; Stephans, Kevin; Qi, Peng et al. (2013) Assessing feasibility of real-time ultrasound monitoring in stereotactic body radiotherapy of liver tumors. Technol Cancer Res Treat 12:243-50
Tutkun ?en, H; Lediju Bell, Muyinatu A; Iordachita, Iulian et al. (2013) A Cooperatively Controlled Robot for Ultrasound Monitoring of Radiation Therapy. Rep U S 2013:3071-3076
Khashab, Mouen A; Kim, Katherine J; Tryggestad, Erik J et al. (2012) Comparative analysis of traditional and coiled fiducials implanted during EUS for pancreatic cancer patients receiving stereotactic body radiation therapy. Gastrointest Endosc 76:962-71