Technique for Respiratory Gated Radiotherapy using Low Frame Rate MRI and a Breathing Motion Model
SUMMARY
UCLA researchers in the Department of Radiation Oncology have developed a novel method to gate radiotherapy using low frame rate MRI sequences to reduce damage to adjacent tissues during radiotherapy.
BACKGROUND
Taking respiratory movements into account during radiotherapy has always been a major concern in radiotherapy treatments that are affected by lung movement (e.g. thoracic or abdominal cancer). Currently, a common method for gating radiotherapy to prevent healthy tissue damage is by using MRI sequences. While MRI can provide better visualization of the tumor, some MRI sequences (e.g. T2-weighted sequences) are too slow to account correctly for the human breathing cycle. A method to improve the accuracy of MRI-guided radiotherapy would greatly improve radiotherapy.
INNOVATION
Researchers at UCLA have developed a novel method to use low frame rate MRI sequences for radiotherapy gating. The technology enables accurate modeling of patient-specific respiratory motion from continuously acquired MRI images. The method is able to predict respiratory motions with high accuracy, enabling correct gating of radiotherapy for a more precise and safer treatment.
APPLICATIONS
- MRI–guided radiotherapy
- Assessment of tumor response to therapy over time
ADVANTAGES
- Can improve accuracy of MRI-guided radiotherapy
- Can be used to assess tumor response to therapy during treatment
- Can collect functional images during gated treatment
RELATED MATERIALS
- Ginn, John S., et al. "Characterization of spatial distortion in a 0.35 T MRI-guided radiotherapy system." Physics in Medicine and Biology 62.11 (2017): 4525.
- Lamb, James M., et al. "Dosimetric validation of a magnetic resonance image gated radiotherapy system using a motion phantom and radiochromic film." Journal of Applied Clinical Medical Physics 18.3 (2017): 163-169.
- Chow, Phillip E., et al. "Dosimetric effects of couch position variability on treatment plan quality with an MRI-guided Co-60 radiation therapy machine." Medical physics 43.8 (2016): 4514-4519.