Clinical Trial Details
— Status: Recruiting
Administrative data
NCT number |
NCT04657042 |
Other study ID # |
15547 |
Secondary ID |
|
Status |
Recruiting |
Phase |
|
First received |
|
Last updated |
|
Start date |
November 5, 2020 |
Est. completion date |
December 31, 2025 |
Study information
Verified date |
December 2020 |
Source |
University of Virginia |
Contact |
Roselove N Nunoo-Asare, MA |
Phone |
4342436074 |
Email |
RNN3B[@]VIRGINIA.EDU |
Is FDA regulated |
No |
Health authority |
|
Study type |
Observational
|
Clinical Trial Summary
The purpose of this study is to develop new ways to make medical images of the lungs and
liver of adults using a technique called four-dimensional magnetic resonance imaging
(4D-MRI). This technique produces three-dimensional movies of the inside of the chest and
abdomen while the patient is breathing. (The fourth dimension is time!)
This new way of medical imaging is being developed to help cancer patients undergoing
radiation therapy. Radiation therapy is used to treat cancerous tumors. For radiation therapy
to be effective, the precise size, shape, and location of the tumor within the body must be
known. A particular difficulty for radiation treatment of lung and liver cancer is that the
tumor moves during treatment because the patient is breathing. Therefore, tumor motion must
also be incorporated into the treatment plan. This study aims to improve radiation treatment
planning through better targeting and dose estimation based on 4D-MRI. Before this new
imaging method can be used for radiation treatment planning, it must be tested in living,
breathing volunteers.
Description:
Radiotherapy for cancer has been a forerunner of personalized medicine, developing
individualized treatments based on patient-specific anatomical information. Despite many
advances in radiotherapy over the past decade, which have effectively enhanced local or
loco-regional tumor control for many patients, there remains substantial room for
improvement. The challenges for radiotherapy to further widen the therapeutic window in the
era of precision medicine are mainly two-fold: (a) further improve radiation dose conformity
to the defined target volume, and (b) adapt novel biological strategies for personalized
treatment. Four-dimensional (4D) imaging and deformable image registration (DIR) are key
tools in modern radiotherapy, playing critical roles in many recent advances, including 4D
radiotherapy, adaptive radiotherapy, and treatment assessment. However, current 4D imaging
and DIR technologies are facing significant challenges as the requirement for precision
increases.
The current standard of 4D imaging in radiotherapy is 4D-CT. However, it has two major
limitations preventing it from precision radiotherapy applications: (a) low soft-tissue
contrast. 4D-CT is therefore not ideal for abdominal applications; (b) motion artifacts
caused by irregular breathing. 4D-CT motion artifacts have been shown to cause errors in
various radiotherapy applications, including motion measurement, target volume delineation,
dose calculation, DIR, and lung ventilation calculation. 4D-MRI is an emerging 4D imaging
technology for radiotherapy. It has superior soft-tissue contrast to 4D-CT and is therefore
superb for abdominal imaging. Despite many recent advances in 4D-MRI, current 4D-MRI
implementations have inadequate image quality for precision radiotherapy application due to
at least one of the following deficiencies: low temporal and/or spatial resolutions, long
image acquisition time, and suboptimal contrast in the lungs. Resulting 4D-MRI images lack
sufficient anatomical details for clinical applications, which can adversely affect the
performance of DIR. Current DIR techniques focus on morphological similarity but not on the
physiological plausibility of the deformation. Studies have shown that an increased
morphological similarity of the aligned data does not always imply increased registration
accuracy. Therefore, more sophisticated approaches are desirable.
The investigators will take a systematic approach to address the aforementioned limitations
of 4D imaging and deformable image registration (DIR) based on the development and
cross-fertilization of two major techniques: ultra-quality 4D-MRI and physiological-based
hybrid DIR. There are two parts of this research, comprising three main objectives:
Part 1. Technical development in healthy subjects: The investigators will extend their
existing pulse sequence strategy for ultra-quality 3D MRI to enable ultra-quality 4D-MRI.
Compared to 4D-CT and current 4D-MRI techniques, the proposed ultra-quality 4D-MRI technique
offers the following advantages: (a) high spatial resolution (1.5 mm isotropic) with rich
image features (e.g. vessel trees) in the whole torso; (b) high temporal pseudo-resolution
(>20 phases/cycle); and (c) (nearly) free of motion artifacts.
• Objective 1: Develop an MRI pulse sequence and image reconstruction pipeline that generates
images meeting these three design goals.
Part 2. Evaluation of 4D-MRI in a patient study: 4D-MRI will be compared with existing DIR
and 4D-CT methods. There will be two classes of comparisons, each formulated as a separate
objective:
- Objective 2: Compare motion modelling based on 4D-MRI with deformable image registration
(DIR) in healthy volunteers and cancer patients. An improved motion modeling method will
be developed that is tailored for the ultra-quality 4D-MRI applications. The
investigators hypothesize that a new motion modeling method based on 4D-MRI will
outperform current DIR algorithms for respiratory motion estimation. This hypothesis
will be tested by comparing the new method to five DIR algorithms which include a mix of
commercial software and publicly available algorithms.
- Objective 3: Compare 4D-MRI with 4D-CT in lung and liver cancer patients. The overall
hypothesis of this objective is that the ultra-quality 4D-MRI provides better image
quality than 4D-CT for motion management of radiotherapy in the lungs and the liver,
especially in patients with irregular breathing.