'The World'

By Art Gib

Radiation therapy takes on several forms. Beam application, which is the most common one, involves targeting and bombarding a tumor with subatomic particles. The particles will simply pass through the skin invisibly and into the tumor, disrupting and often destroying the malignant cells

The trick is to be as accurate and precise with the beam as possible, not only with where it's targeted, but by regulation the strength of the beam particles sent through. Radiation beam tools used by the radiation oncologist of yesteryear were unwieldy. They would often find success in controlling or stopping some cancer, but also they would discover destroyed surrounding tissue, which sometimes caused secondary cancer development created by the treatment.

With the culmination of targeting tools and software, as well and refining the actual beam application, radiation oncology has become more effective and more sought by future radiation oncologist MDs.

IMRT and IGRT Beam Technology

The intensity-modulated radiation treatment uses electron beam accelerators that regulate their strengths when passing through the patient's body, concentrating the power of the beam on the tumor while avoiding most healthy tissue surrounding. The
radiation oncologist will normally use a CT scanner to get a 3-D image of the tumor and
input that software so the machine can plan its road map.

Since the particle beams go through healthy tissue to get to the tumor normally, the healthy tissue it passes through has to be as unharmed as possible. To help avoid this, the IMRT machine will come at the tumor from multiple angles at once. Each beam is described as pencil-thin beams of light that converge on the tumor. They will converge as they meet the tumor which will concentrate the particle's power on the mass.

The Image Guided Radiation Therapy technique (IGRT) is basically a step up from the IMRT. It is currently filling many clinical offices and the popularity is gaining among the radiation oncology field. It's big right now because it has technology that can feed the computer real-time information gathered from the CT scanner, ultrasound machine or x-ray.

The reason real-time information is needed is because often, when a tumor is targeted and mapped in the doctor's office and sent to the IMRT machine to go to work, the organs and internals within the patient do shift a little. This can create some margin of error when the work is performed.

With IGRT the radiation oncologist or other clinician can run an imaging scan while having the particle accelerator follow that scan's live image. This leaves more healthy tissue that can stay unscathed in the process.