Principles of radiation therapy, Physics

Principles of radiation therapy:


The basic principle of radiation therapy is to maximize damage to the tumor while minimizing damage to the normal tissue.Factors that determine how much radiation required are:


1.    The type of radiation
2.    The environment of the cell (for example its blood and oxygen supplies 
3.    The type of cell.
4.    The nucleus of the cell is more sensitive of radiation.

Some types  of radiation are more effective in killing cells or  have a higher relative biological effects(RBE)


RBE: The ratio of the number of grays of 250kVp  x- rays needed to produce a given biological effect to the number of grays of the test radiation needed to the same effect .

Lethal dose for 50%(LD50 ): the quantity of radiation that will kill half of the organisms in a population (cells ,mice, people ect)
 LD30: Theamount of radiation that will kill 50% of the organisms in 30 days ,its value for humans about 4.5 Gy.

Posted Date: 10/1/2012 7:43:54 AM | Location : United States







Related Discussions:- Principles of radiation therapy, Assignment Help, Ask Question on Principles of radiation therapy, Get Answer, Expert's Help, Principles of radiation therapy Discussions

Write discussion on Principles of radiation therapy
Your posts are moderated
Related Questions
Explain the Maxwell's equation in electromagnetism connecting magnetic field vector and electric displacement vector.

Unit vector which is perpendicular to the resultant of 2i+3j+5k and -i+2j+7k ; and passes by (1,2,4)

Michelson-Morley experiment (A.A. Michelson, E.W. Morley; 1887) Probably the most popular null-experiment of all time, designed to check the presence of the proposed "lumenife

The points of maximum amplitude are called as antinodes. At ends density and air pressure both are very low.

Q State Ohm's law. At a steady temperature that the steady current flowing through a conductor is directly proportional to the potential difference between the two ends of the

A seat of EMF is in sequence with a resistor R1 and with a parallel combination of two other resistors R2 and R3. R2 is a changeable resistor whose resistance can be changed just b

A transformer has 124 turns on the  primary coil and 18,600 turns on the  secondary coil. a. Is this a step-down or a step-up  transformer? step-up transformer

The forced harmonic oscillations have same displacement amplitude at frequencies ω 1 = 400 Hz and ω 2 = 800 Hz. Evaluate the resonance frequency at which the displacement is maxi

The waves which needs medium for their propagation are known as mechanical waves. Example : Waves on string and spring, waves on water surface, sound waves, seismic waves.

A jogger runs at a constant rate of 10.0 m every 2.0 s. The jogger starts at the origin, and runs in the positive direction for 3600.0 s.The figure below is a position-time graph s