2. • Cancer patients are treated by radiation,
surgery and chemotherapy
• The treatment method proving increasingly
effective is radiation, used by itself or ineffective is radiation, used by itself or in
combination with other modalities.
• The principal radiation modality for the
treatment of deep seated tumors is x-rays of
very high energy and penetrating power.
3. • Such x-rays are created when high energy
electrons are stopped in a target material such
as tungsten.
• Alternatively the electron themselves may be• Alternatively the electron themselves may be
used directly to treat more superficial tumors.
• The linear accelerator accelerates charged
particle in straight line.
5. • The electric field is the force that a unit positive
charge would feel if placed between the plate.
• The E filed strength one volt per cm (1 V/cm).
• If electrons denoted by “e” are released from• If electrons denoted by “e” are released from
negative plate (cathode) they will be accelerated
by the force of E field to the positive plate anode.
• An electron volt (eV) is the energy gained by the
electron accelerated across a potential difference
of one volt.
6.
7. • The energy gained by the electron depends on
the potential difference between the anode
and cathode
