الفهرس 
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Abstract
The goal of this study was to compare the dosimetry results
that were obtained by using Convolution, Superposition and Fast
Superposition algorithms in Conventional Radiotherapy, ThreeDimensional Conformal Radiotherapy (3D-CRT), for different
sites, namely, Lung, breast, head and neck, prostate, rectum.
Treatment plans were created using 6 MV and 10MV Photon beam.
Statistical analysis was performed by comparing the maximum
dose and conformation number CN and PITV with convolution,
superposition, and fast superposition, algorithms.
The differences were statistically significant among the
three different techniques (P < 0.01) for PITV (defined as the ratio
of the prescription isodose volume (PI) and Target Volume (TV)
and Conformal Number (CN).
In this study we compared the Monitor Units (MUs) in
different algorithms we noted in most cases values highest with
convolution than others.
The volume of the body received 2Gy in most cases
convolution has the higher value than other algorithms. But in the
volume of the body received 5Gy in most cases the calculation with
fast superposition higher than other algorithms.
Results
This chapter shows the results of cancer cases of five groups
of plans including head and neck, breast, lung, rectum, and prostate
treated with the different algorithms superposition, convolution,
fast superposition using Xio treatment planning system.
4.1 Dose Volume Histogram
The dose-volume evaluation for the PTV and organ at risk
with the different algorithms was performed. All plans were
optimized such that 95% of the volume of the PTV received 95%
of the prescribed dose.
The solid line represents the dose in superposition while the
dashed line dose in convolution and the dotted line dose in the fast
superposition algorithm. Figure 4.1 describes a dose-volume
histogram for head and neck cases which contains the
measurements performed for PTV, parotid, and spinal cord with
three algorithms. The prescribed dose was 5000 cGy. For each
patient, Dose-Volume Histograms (DVHs) data revealed
dosimetric measurements including maximum dose, minimum
dose, and mean dose. The breast case DVH also recorded
measurements for PTV with three algorithms with prescribed dose
was 4500 cGy as shown in figure 4.2.