4DMRI-adaptive proton radiation therapy for abdominal cancers: A retrospective reconstruction review and conversion of 4DMRI to virtual 4DCT

The primary imaging modality for image-guided radiotherapy (IGRT) is computed tomography (CT), primarily because it directly provides a quantitative spatial representation of radiation attenuation in the patient. An initial CT, called the simulation CT, is acquired for every patient in order to design the treatment plan, and cone-beam CT (CBCT) is often acquired in the treatment room to verify patient positioning and for adaptive radiotherapy, meaning that the treatment plan is modified to account for anatomical changes that occur during the course of radiotherapy. One problem with CT is that it also gives the patient additional radiation dose, and when it is used for daily patient positioning or when four-dimensional CT (4DCT) is required to account for respiratory motion, this dose can be significant (1-9).

You may be eligible for this study if you meet the following criteria:

• Conditions: TBD, tbd, tbd
• Age: 99 years or below
• Gender: All