الفهرس 
Literature Review
History Of Total Body IrradiationOnly 14 pages are availabe for public view
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Abstract
Aim of the present study is devoted to evaluate the dose at different points
defined on the patient using semiconducting diodes and thermoluminescence
detectors to execute verification of the dose at these relevant points calculated by
means of movement couch and (Beam - Zones method) of the Total Body
Irradiation Technique.
In this technique; 11 patients using 6MV X-ray in (non-standard)
conditions lying on the couch (supine and prone positions) were treated. Barry
translation couch positioned in the extended SSD on the floor of the treatment
room of distance (200 cm) was used. The couch was moving (280 cm) with fixed
machine dose rate (50 cGy/min), and constant velocity which is been calculated
from the (beam- zone method) depending on the length, different separation in
different organs, thorax wall separation, and the lung density of each patient
individually.
Comparison between calculated dose values at (orbit, lung under the shield,
umbilicus, and knee) and the corresponding results measured by means of
semiconductor detectors proves that there is a quite agreement with deviation in the
range of (-17.18 ± 3.28) %, (-11.13 ± 3.72) %, (-13.8 ± 3.14) %, and (-6.65 ± 1.56)
%, at four different sites orbit, lung under the shield, umbilicus, and knee
respectively.
Additionally, further comparison between the calculated dose values and
the corresponding measured results performed using TLD dosimeters at the same
four sites proves that the deviation falls in the range of (-23.27 ± 11.77) % , (-14.18
± 10.28) % , (-16.52± 7.42) % , and (-17.27 ± 7.01) %, respectively.Finally; our results suggests that the semiconductor diodes and
thermoluminesence detectors must be used for TBI quality assurance monitoring,
although semiconducting diodes should remains the standard when critical dose
measurements are performed due to its high accuracy in dose detection plus that it
gives us an online dose verification in the same time of the session .
The semiconducting diodes, thermoluminesence detectors )TLD( results,
both of these different techniques of verification goes in the same direction of
under dose from the original dose calculation and beam zones method calculations
agreed within acceptable margins, more accurate and consistent results of dose
homogeneity in dose delivery is possible by using the variable speed translation
couch in addition of tissue compensators in extremities and neck sites, detectors
which have less uncertainty in measuring the delivered dose is recommended.