Cyberknife & Tomotherapy
Radiosurgery | Tomotherapy
Overview | Cyberknife Overview
What is the TomoTherapy Hi·Art
System® ?
The TomoTherapy Hi·Art SystemĘ is a new way to deliver radiation
treatment for cancer. It delivers a very sophisticated form of IMRT,
or intensity modulated radiotherapy, and integrates treatment planning, patient
positioning, and treatment delivery in one system.

In order to understand what all this means for cancer treatment,
it might be helpful first to get some background information on
radiotherapy.
Treating cancer with radiation
Radiation is one of the most effective cancer treatments available.
It works by damaging the cells it strikes: when the cancer cells
are damaged enough, they will die. But what happens to healthy
cells that are struck by the radiation beam? The key factor for radiotherapy
is that healthy cells can repair themselves better than cancer cells. That's
why radiotherapy treatments are divided into many treatments, or fractions,
over several weeks. Delivering a little radiation to the tumor
area every day gives healthy cells time to recover between each session,
while causing irreparable damage to more and more cancer cells.
Radiation treatment is also usually directed at the tumor
from several different directions, so that more radiation is targeted
on the tumor, but a lesser dose is spread over the surrounding
healthy tissue.
Even though normal tissue can recover from exposure to radiation,
there are often side effects, and of course too much radiation
can damage normal tissue beyond repair. Until recently, it was
very difficult for doctors to deliver enough radiation to kill a tumor
without causing painful or debilitating side effects. Some side effects
might go away once the treatment is complete, but others could continue
to affect quality of life for years.
Of course, one of the goals of any radiation therapy is
to avoid healthy tissue as much as possible, but some healthy cells
will be damaged by the radiation treatment. So doctors and scientists
have begun to look for better ways to deliver enough radiation
to the tumor, while sparing normal tissue as much as possible.
One of the most promising methods is IMRT, or intensity modulated radiotherapy.
How does the TomoTherapy Hi·Art
System® work ?
The TomoTherapy Hi·Art SystemĘ combines treatment planning, patient
positioning, and treatment delivery into one system, in order to deliver
precise treatment doses without increasing the radiation deposited
on healthy tissue.
Planning
Before beginning a TomoTherapy Hi·ArtĘ treatment, the doctor uses
3-D images (for example, from CT) and special software to establish the precise
contours for each region of interest (tumor) and any regions at risk (sensitive
organs or structures). The doctor decides how much radiation the tumor should
receive, as well as acceptable levels for surrounding structures. Then the
TomoTherapy Hi·Art SystemĘ calculates the appropriate pattern, position,
and intensity of the radiation beam to be delivered, to match the doctor's
prescription as closely as possible.
Patient Positioning
The TomoTherapy Hi·Art SystemĘ will allow doctors to take a special
CT scan just before each treatment, so they can verify the position
of the tumor, and adjust the patient's position if necessary to make sure
the radiation is directed right where it should be.
Helical Treatment Delivery
The TomoTherapy Hi·Art SystemĘ combines IMRT with a helical (or
spiral) delivery pattern to deliver the radiation treatment. Photon
radiation is produced by a linear accelerator (or linac for short), which travels
in multiple circles all the way around the gantry ring. The linac moves in
unison with a device called a multileaf collimator, or MLC. The computer-controlled
MLC has two sets of interlaced leaves that move in and out very quickly
to constantly modulate the radiation beam as it leaves the accelerator. Meanwhile,
the couch is also moving, guiding the patient slowly through the center
of the ring, so each time the linac comes around, it's directing the beam at
a slightly different plane.

TomoTherapy's Advantages
The TomoTherapy Hi·Art SystemĘ has been designed to advance the
goals of more accurate treatment with fewer side effects. How does
the Tomo(tm) Process help accomplish this?
Precise Planning
The TomoTherapy Hi·Art SystemĘ uses a treatment planning optimizer,
which is easier to use than conventional treatment planning systems.
Precise Positioning
The TomoTherapy Hi·Art SystemĘ uses special verification CT to confirm
the position of the patient's tumor before each treatment fraction,
so the clinician can adjust the plan on the spot to make sure the radiation
is directed right where it should be.
Precise Delivery
While conventional radiotherapy delivers a wide beam of radiation
from just two or three directions, the TomoTherapy Hi·Art SystemĘ combines
sophisticated IMRT with spiral delivery. So the desired radiation gets
concentrated on the tumor, and less radiation gets deposited on surrounding
healthy tissue.
System Integration
The TomoTherapy Hi·Art SystemĘ is an all-in-one system that eliminates
the need for a simulator, separate treatment planning computers, block
cutting and compensator molding facility, and portal imaging systems.
Cyberknife & Tomotherapy Radiosurgery | Tomotherapy
Overview | Cyberknife Overview
For consultation appointments with Dr. Duma or
for more information regarding his brain tumor, GammaKnife radiosurgery,
and Parkinson's Disease programs at Hoag Memorial Presbyterian
Hospital in Newport Beach, California (Orange County), please contact:
949-642-6787
Or E-mail Dr. Duma directly: drduma@cduma.com
Back to Top |