TOMOTHERAPY

A few weeks ago, our lecturer gave a task about ‘Tomotherapy’ to our group.We are supposed to explain what is tomotherapy, its function, advantages and disadvantages of tomotherapy compared to normal radiation therapy.

TOMOTHERAPY

What?

   -   Radiation treatment for cancer.

-             -   3-D Imaging of target tissue.

-             -  Helical delivary pattern.

-             -   Intensity Modulation Radiotherapy (IMRT)

  - Multileaf Collimator (MLC)

  -   Radiation concentrates on moving target tissue.

There are 2 type :-

     1)      Serial (NOMOS corp) : The delivary of multiple fan beams with discrete table increments between each axial gantry arc.

     2)      Helical (Tomotherapy Inc.) : Continous synchronized gantry and table motion. From the patient’s point of view, the source describes a helical trajectory.

This is the diagram that showing the component presence in the tomotherapy machine.

Source : google

How it works?

A short 6 MV linac is collimated by jaws and a binary multileaf collimator. The treatment head rotates on a gantry in the x/z plane while a patient is continuously translated through the bore of the machine in the y-direction – the therapy analogue of spiral CT.

Function

       1)      For cancer treatment – Since there are presence of linac. The treatment is given slice by slice while normal radiation therapy is not.

Linac?

A linear accelerator (LINAC) customizes high energy x-rays to conform to a tumor’s shape and destroy cancer cells while sparing surrounding normal tissue. It features several built-in safety measures to ensure that it will not deliver a higher dose than prescribed and is routinely checked by the medical physicist to ensure it is working properly.

        2)      By presence of CT Scan, it will :-

-          Take image to check the location of tomour before give treatment to the patient so that the tumour is not mislocated if there is weight loss of patient.

-          If there are high difference of patient’s weight, patient maybe need to another treatment planning.

-          CT will show the 3D image and showing slice by slice of body part.

Advantage & Disadvantage

Advantage	Disadvantage
1)    Delivers radiationfrom all 360◦of the axial plane.	1)      Delivary is exclusively coplanar, currently nonplanar fields cannot be deliver.
2)      3D imaging is integral to treatment alignment.	2)      Expensive
3)      Excellent image quality.
4)      Binary collimator and helical delivary to enable highly conformal and precise treatment.
5)      Fully integrated system- easy to use.