Radiotherapy

1. Radiotherapy
Physical fundamentals
Aliya Kadyrova
associate professor of radial diagnostic
and radiotherapy chair, PhD

3. remote gamma setting

4. simulation

6. Temporary tattoos

7. Aim of radiation therapy

9. Radiation effects on tumor
• Different tissues have unequal
radiosensitivity and the rate of
recovery of radiation damage. This is
due to the rate of cell division - a
process in malignant tumors occurs
rapidly at each stage obtained by
accumulating damage and finally
giving rise to non-viable cells
• In healthy tissue process is slower -
the cells have enough time to recover
(be repaired), unlike tumor
• For the success of this process
requires that the dose received by the
cells was not very high. Therefore,
radiotherapy is carried out daily
exposure in small doses.
• Fraction is a daily dose. There are
small and large fractions

10. Field exposure that created by the radiologist on the basis of the
projection image of the patient. Left is multileaf collimator

11. a- single field; b - multiple-field;
c - rotation; d - sector; e - tangent.

12. Map of a cross section of
the abdomen in patient
with metastasis of
testicular cancer in
retroperitoneal lymph
nodes
It was decided to
hold EBRT
The figure shows two
variants of fields of
radiation with the
corresponding
picture isodose.
Which option is
preferable?

13. Distribution of radiation energy absorbed in the tissues under
the influence of different types of radiation
Use physical characteristics of waves – 1. path length of the wave. 2. Ionization peak

14. Schematic illustration of the different volumes
• Gross tumor volume (GTV) is
defined as all known gross tumor
that is seen on imaging, palpable
or determined in any other way.
• Clinical target volume (CTV) is
defined as areas suspected of
harboring microscopic cancer
cells.
• Planning target volume (PTV) is
a margin of normal tissue
surrounding the previously
described volumes that is
included in the radiation volume
to account for organ movement
and inaccuracies of daily setup.
Inaccuracies in daily setup can
be minimized by using proper
immobilization technology.

16. • Radiation sickness is illness
and symptoms resulting from
excessive exposure to ionizing
radiation.

21. • Радиоэмболизация.
Введение радиоактивных
частиц в артерию, ответственной
за кровоснабжение опухоли.
Таким образом, частицы
поступают непосредственно в
опухоль и снижается токсичность
для окружающей печёночной
ткани и организма в целом. Для
этого проводится селективная
ангиография печёночной артерии
с последующим введением
заранее заказанного
радиопрепарата. Микрочастицы
застревают в микрососудах
опухоли и происходит местное
облучение опухоли, без лучевой
нагрузки на здоровую печень.