The four dimensional computed tomography scanner (4D CT Scanner), is the next generation in medical imaging. It is faster and more accurate than traditional CT. With the 4D CT Scanner, in addition to obtaining a 3D image of the body, also the movement is recorded. The movement is registered throughout the breathing cycle, capturing the location of the internal organs along this time.
The ability to monitor and time the movement of internal organs, throughout the breathing cycle, is especially important in treatment of cancers that are located near or on organs that move with breathing, as in the area of the chest and abdomen.
A complete scan of the body with the 4D CT Scanner takes about 30 seconds. The device spins in a corkscrew motion, taking images all the time. The output provides information on the body’s breathing, the corresponding tumor movement, and the effect of the surrounding organs on the position of the tumor.
New treatment capabilities due to the 4D CT Scanner
The new imaging capabilities, provided by the 4D CT Scanner, support development of more accurate treatments for tumors that move, such as what is called intensity-modulated radiation therapy (IMRT), which enable:
- Administrating the radiation treatment only when the tumor is in the correct position in the breathing cycle, and stopping when it is not.
- Targeting the tumor precisely in terms of both the timing and the angle.
- Avoiding the side effects of damage to surrounding organs and healthy tissue, such as radiation pneumonitis (damage to the lungs caused by radiation on healthy tissue just around the tumor).
- The use of higher levels of radiation, which are more effective than low levels, as the danger to surrounding healthy tissue is reduced or eliminated.
The fourth dimension in imaging has brought with it new capabilities for cancer treatment. It is enabling targeted radiation of the tumor with less damage to surrounding healthy organs and tissue. This brings new hope especially for patients suffering from the most common cause of death due to cancer in the world, lung cancer.