What is MU in radiation therapy?
What is MU in radiation therapy?
From Wikipedia, the free encyclopedia. A monitor unit (MU) is a measure of machine output from a clinical accelerator for radiation therapy such as a linear accelerator or an orthovoltage unit.
What is DMAX radiotherapy?
Dmax. When a radiation beam interacts with tissue, a certain depth of tissue is required before we see the maximum amount of radiation (maximum dose or dmax). This region is called the build-up region and is responsible for the skin sparing effect.
What does SSD mean in radiation therapy?
Modern photon beam radiotherapy is carried out with a variety of beam energies and field sizes under one of two set-up conventions: a constant source to surface distance (SSD) for all beams or an isocentric set-up with a constant source to axis distance (SAD).
What are MU units?
The lowercase Greek letter mu (µ) is used to represent the prefix multiplier 0.000001 (10 -6 or one millionth). In some texts, the symbol µ is an abbreviation of micrometer(s) or micron(s). These two terms both refer to a unit of displacement equal to 0.000001 meter or 0.001 millimeter.
Why does PDD increase with SSD?
The percentage depth dose (PDD) increases with SSD due to the effects of inverse square law. NO dependance on the SAD or SSD. and hν constant TMR decreases with increasing z.
What is DMAX 10 MV?
For 10 MV d(max) is 2 cm for a field size of 5 x 5 cm2 and 2.5 cm for a 10 x 10 cm2 field.
What is inverse radiation?
An inverse radiation analysis is presented for determining optical thickness and single scattering albedo from the exit intensities for an isotropically scattering slab of finite thickness. The method involves solving the non-linear least square equations constructed from the measured data and the exact solutions.
What is field size in radiotherapy?
at the center of the front surface of the radiation source. The dosimetric, or the physical, field size is the distance. intercepted by a given isodose curve (usually 50% isodose) on a plane perpendicular to the beam axis at a stated. distance such as the SSD or the source‑axis distance.
What is the MU in physics?
coefficient of friction, ratio of the frictional force resisting the motion of two surfaces in contact to the normal force pressing the two surfaces together. It is usually symbolized by the Greek letter mu (μ). Mathematically, μ = F/N, where F is the frictional force and N is the normal force.
How is Mu calculated in external beam RT?
MU calculation • In external beam RT, monitor units (MU) or beam-on time for a given treatment plan allows the RT technologists to deliver the actual dose to a patient. • MU are calculated by the TPS by means of sophisticated algorithms from the calculated dose distribution and dose prescription.
What do you need to know about the MMU calculator?
Mmu Calculator is a compact tool that enables you to analyze the patient details and automatically calculate the MU value. You just need to enter the photon and electron field details in the main window in order to view the MU value in real time.
How to see the mu value in real time?
You just need to enter the photon and electron field details in the main window in order to view the MU value in real time. The program is also able to create PDD graphs for photons, electrons or mixed photon and electron fields.
Where to measure collimator scatter fractor in Mu?
Most commonly measured at isocenter. Key Point: In MU calculations, Collimator Scatter Fractor should always be taken as the field size at SAD. Accounts only for scatter arising from the phantom.