Oncology / / May 16, 2016
medical radiology techniques are very important in the diagnosis of cancer and are able to provide:a) early diagnosis of tumors;
b) the establishment of the localization process (the primary tumor or its metastases);
c) improving the accuracy of the clinical classification (for example, malignant lymphoma);
g) checking the effectiveness of treatment;
d) early detection of recurrence.
Nuclear Medicine - is an area of clinical medicine that studies and uses radioactive isotopes to diagnose and treat diseases.Thus radioisotopes used in nuclear medicine, are primarily artificial.
Isotopes - is different nuclides specific element, ie,they are characterized by the same serial number of the element (Z is the number of protons in the nucleus) and the same position in the periodic system of elements.They differ from each other in the mass number A.
A = Z + N
where N - number of neutrons in the nucleus.The chemical properties of radioactive isotopes are almost the same as that of the stable ele
Radioactive isotopes can be used for preparation of nuclear medicine used in labeled pharmacological compounds.
the decay to a stable nuclide radioactive isotopes emit different types of radiation (alpha, beta, gamma).Radioactive decay is accompanied by the emission of gamma rays of high energy, optimal for outdoor detection of radioisotopes location.Radiation penetrating from the body, can be determined externally by means of special devices.
scintillation counter device is presented to the account in which gamma rays are often absorbed in NaI crystal, and the photons of visible light are recorded on a photoelectron multiplier.After conversion into electrons, which subsequently flow increases, the output signal is obtained from the other anode.The output signals can be registered numerically in time (pulse counter) or determined as the average count rate for a short period of time (pulse integrator).Scintigram possible to observe the distribution of radioactive isotopes in the body.
addition stsintillografov (scintillation counters), in which over a given area detection continuously moving a scintillation counter, scintillation cameras are used, allowing direct capture the distribution of radioactive isotopes in the body or the whole body thanks to the large scintillation crystal and multiple photomultiplier.
labeled pharmacological drug used in the diagnosis of cancer, must meet the following criteria:
a) he must progressively accumulate in the tumor;
b) the accumulated amount should be kept for a long time required for outdoor activity measurement;
c) labeled pharmacological drug should not accumulate in the tissues around the tumor or can be stored in very low concentrations;
d) labeled pharmacological compounds have excreted the largest in a few days.
09 May, 2016
09 May, 2016