Real-time Tumor Localization and Guidance for Radiotherapy Using Ultrasound (US) and Magnetic Resonance (MR)

Real-time Tumor Localization and Guidance for Radiotherapy Using Ultrasound (US) and Magnetic Resonance (MR)

The primary objective of this protocol is to evaluate the feasibility of acquiring simultaneous 4D ultrasound and 4D MRI scans. The imaging performance of the US and MRI scans will be characterized. The secondary objective of this study is to determine if several salient features identified in the US scan can be used to predict target motion identified in the MR scan.

The goal of radiotherapy treatment of cancer is to cure or locally control the disease while minimizing complications to healthy tissue. Given the complexity of tumor and normal tissue response to radiation, precise and accurate delivery of absorbed dose distributions, within known tolerances, is necessary to achieve the maximum therapeutic ratio. The complex treatment process of radiotherapy introduces geometrical uncertainties including respiratory induced tumor motion. The goal of this research is to develop and validate a novel image-guidance technique to directly track tumor motion using a 4-dimensional (4D) planar ultrasound (US) transducer during radiation therapy that is coupled to a pre-treatment calibration training image set consisting of a simultaneous 4D ultrasound and 4D magnetic resonance imaging (MRI) acquisition. The image sets will be rapidly matched using advanced image and signal processing algorithms, allowing the display of virtual MR images of the tumor/organ motion in real-time from an ultrasound acquisition.

Inclusion Criteria (Healthy Volunteers):

• Must be eighteen (18) years of age or older.
• Must be able to provide informed consent.

Inclusion Criteria (Patients):

• Patients diagnosed with malignancies of the liver.

Exclusion Criteria (All):

• Under the age of eighteen (18) years.
• BMI exceeds the size of the bore of the MRI scanner.
• Unable or unwilling to provide informed consent.
• Contraindications, as described in the volunteer consent form, to MR or US scanning such as but not limited to accidental or implanted ferrous metal and/or implanted devices whose function can be disturbed by the main magnetic field, gradient magnetic fields, or radiofrequency energy.
• Women who are pregnant, suspect they might be pregnant or breastfeeding.