Radiological center of INR (Troitsk)

The primary goal:

  • irradiation of malignant tumors by protons only or in a combination with irradiation by photons. 

Basic facilities:

  • The proton linac (energy 74 –247 MeV),
  • The linear electron accelerator SL-75-5-МТ (energy up to 6 MeV). 

The Center also consists of:

  • The proton-beam transport channel,
  • 2 treatment rooms (protons and photons),
  • The ambulatory for 50 patients per day,
  • X-ray laboratory for topometry and therapy.

Advantages of protons for radiotherapy:

  • Due to the specific depth dose profile (red line in the picture), protons allow to destroy only tumors without damaging the surrounding healthy tissues.
  • Proton (hadron) therapy has no alternative when tumours are close to critical organs. 
  • Protons allow to decrease at least twice the dose delivered to neighbor healthy tissues.

The INR linear proton accelerator

Comparison with other accelerators, used in Russia for proton therapy, shows that only INR linac can provide the application of new methods of radiotherapy (beam scanning, beam rotation in Gantry, etc.). The future parallel beam of H- ions will allow to carry out proton therapy sessions simultaneously with other works on the proton beam.

The medical linear electron accelerator SL-75-5-МТ 
  • The maximal energy of photons–6 МV. 
  • The maximal doze in the isocenter–5 Gray/min.
  • Irradiation field in the isocenter–40x40 cm.
  • Capacity-up to 50 patients per day. 

The boost method (γ+p) will allow to increase the over all performance of the proton linac.

The proton-beam transport channel 

(from the accelerator to the treatment room):

  • Length of the channel–180 m,
  • Focusing lenses–24,
  • Bending magnets–11,
  • High-current beam scanners–14,
  • Low-current beam scanners (luminescent) –2, 
  • Ionization monitors on residual gas (transparent)–2,
  • Beam current monitors (beam current transformer)–4,
  • Vacuum – 10-5 Tor. 

The channel provides the simultaneous transport of beams of protons and H- ions.

 

Proton therapy treatment room 

(with horizontal fixed beam):

The basic equipment:
  • Entrance collimator (above in a picture),
  • The patient positioning system (in a picture: base module of this system with the position accuracy of up to 0.01 mm),
  • Systems of X-ray and laser centration,
  • Individual beam formation system,
  • Beam control and beam monitoring systems.

The tumor maximal size can be up to 10 cm. The treatment room is completed in 2007.

Ambulatory of INR radiological center:

Capacity --50 patients per day.

Personnel–15-20.

The indoor area–550 м2.

Supply systems:

  • System of independent power supply,
  • System of independent water purification,
  • Central air conditioning.

 

The x-ray laboratory for topometry and therapy is constructed.