Radionuclide Imaging

Radionuclide Imaging

1. RadionuclideRadionuclide
ImagingImaging

2. Radionuclide diagnosis - a method of diagnosing a patient
based on the introduction of radiopharmaceutical (RPh) in
organіzm. Using the radionuclide diagnostic can investigate
virtually any organ or tissue in the body, as some of them in
several ways. With clearly defined goals and a continuously
feedback between a radiologist and doctors clinical
departments, the possibilities of radionuclide diagnostics are
almost limitless, especially in case of formulation particularly
difficult diagnoses
RPh consists :
1. molecule, isotropic (native) to the target organ or tissue
2. presence radiolabeling, allowing to determine the dynamics
and the amount of accumulated RPh via an external encoder
(
99m
Tc,
18
F,
123
I )

3. 3. must emit detectable rays or photons. Most frequently use 3. must emit detectable rays or photons. Most frequently use
-radiated RPh.
Ɣ
-radiated RPh.
Ɣ
4. RPh must be radiochemically pure. The purity is 4. RPh must be radiochemically pure. The purity is
determined by concentration of main radionuclide. determined by concentration of main radionuclide.
5. RPh must be apyrogenic. Apyrogenity is determined by 5. RPh must be apyrogenic. Apyrogenity is determined by
the use of reagents, solutions.the use of reagents, solutions.
RPH Safety Regulations
1.RPh must be physiologically determined, i.e. it must
selectively be absorbed by specific organ, inserted into
it’s metabolism and show the function of organ or
organism.
2. RPh must be low-radiotoxic, i.e. to give minimal radiation to
organism and critical organ.
The radiotoxicity of RPh is determined by T 1/2 /Тphys/.Time
of the half amount of radionuclide decay.

4. The widely used radionuclides are followingThe widely used radionuclides are following::
99мТС99мТС - Т1/2- 6 - Т1/2- 6 hours, for brain tumors, thyriod hours, for brain tumors, thyriod
gland, skeletal system, respiratory system gland, skeletal system, respiratory system
diagnosticsdiagnostics..
I131I131 – Т1/2 – 8,04 – Т1/2 – 8,04 days, for iodine metabolism, days, for iodine metabolism,
liver, kidneys functionliver, kidneys function..
51С51Сrr //27.7 days27.7 days/ - / - in hematologyin hematology..
198Au 198Au //2.697 days2.697 days/ / andand In111 – In111 – for liver, brain for liver, brain
diagnosticsdiagnostics..

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6. Target (critical) OrganTarget (critical) Organ
So, what is target organSo, what is target organ? ?
Target organ – is organ in which the RPh is maximally Target organ – is organ in which the RPh is maximally
accumulated and which is exposed by excessive accumulated and which is exposed by excessive
radiationradiation. . Mostly, it is the organ we want to examineMostly, it is the organ we want to examine..
By safety regulations By safety regulations there are 3 groups of target there are 3 groups of target
organs due to decreasing or radiosencitivityorgans due to decreasing or radiosencitivity::
1.1. groupgroup – – whole body, genitals, bone marrow, small whole body, genitals, bone marrow, small
intestine mucosaintestine mucosa..
2. 2. groupgroup – – muscles, thyroid, fat, liver, kidneys, muscles, thyroid, fat, liver, kidneys,
spleen GI tract, lungs, lensspleen GI tract, lungs, lens. .
3. 3. groupgroup – – skin,bonesskin,bones..

7. Radionuclide LaboratoryRadionuclide Laboratory

All the activity with RPH must undergo in specific offices. All All the activity with RPH must undergo in specific offices. All
equipment must be shielded and RPH should not waste the equipment must be shielded and RPH should not waste the
environment. The laboratory must include following rooms: environment. The laboratory must include following rooms:

Storage facility – 8-10м2 ventilation 5-10 times per hour.Storage facility – 8-10м2 ventilation 5-10 times per hour.

Preparation room - 8-20м2.Preparation room - 8-20м2.

Washing room – 10м2.Washing room – 10м2.

Procedural room - 16-20м2 . Procedural room - 16-20м2 .

Radiometry facility – 20-25м2.Radiometry facility – 20-25м2.

Radiography facility – 15-18м2.Radiography facility – 15-18м2.

Gamma – topography facility – 12-18м2.Gamma – topography facility – 12-18м2.

Room for detection of activity of biological substances – 12м2Room for detection of activity of biological substances – 12м2

Observation room (for outpatients).Observation room (for outpatients).

Sanitary rooms.Sanitary rooms.

8. Methods of radionuclide Methods of radionuclide
diagnosticsdiagnostics
1. 1. ііnn vivo vivo i/venously or per os i/venously or per os..
2. 2. In vitroIn vitro (blood, urina, other biological (blood, urina, other biological
fluids)fluids).. Radioimmunoassay in comparison with Radioimmunoassay in comparison with
biological and biochemical research methods biological and biochemical research methods
has several advantages: high sensitivity, which has several advantages: high sensitivity, which
allows to determine small amounts of the allows to determine small amounts of the
substance, specificity, due to the principle of substance, specificity, due to the principle of
immunological reactions, high accuracy and immunological reactions, high accuracy and
reproducibility of the method. The disadvantages reproducibility of the method. The disadvantages
include a relatively high cost of a standard set of include a relatively high cost of a standard set of
reagents for each blood component.reagents for each blood component.

9. Methods of radionuclide diagnostics (in vivo)Methods of radionuclide diagnostics (in vivo)
1. 1. RadiometryRadiometry – is method, which determines – is method, which determines
radioactivity of the body, organ. This method allows to radioactivity of the body, organ. This method allows to
detect amount of radionuclide in organ or organism.detect amount of radionuclide in organ or organism.
2. 2. RadiographyRadiography..
This method allows to detect distribution, This method allows to detect distribution,
accumulation and elimination of RPH. The result is a accumulation and elimination of RPH. The result is a
curve of the intensity of RPH in target organ during curve of the intensity of RPH in target organ during
period of time (blood circulation, liver, kidneys function). period of time (blood circulation, liver, kidneys function).
This method allows to estimate clearance of blood.This method allows to estimate clearance of blood.

10. Methods of radionuclide Methods of radionuclide
diagnosticsdiagnostics
Blood clearanceBlood clearance – the velocity of blood purification – the velocity of blood purification
from RPH per time. The faster is clearance - the better is from RPH per time. The faster is clearance - the better is
the organ function. A typical example is the radiographic the organ function. A typical example is the radiographic
study of the accumulation and excretion of the study of the accumulation and excretion of the
radiopharmaceutical from lungs, kidney, liver. radiopharmaceutical from lungs, kidney, liver.
Radiographic function in modern devices is combined in Radiographic function in modern devices is combined in
a gamma camera with visualization of organsa gamma camera with visualization of organs

11. Methods of radionuclide Methods of radionuclide
diagnosticsdiagnostics

12. 3. 3. Radionuclide imagingRadionuclide imaging. The technique of painting . The technique of painting
the spatial distribution in the organs of the the spatial distribution in the organs of the
radiopharmaceutical injected into the body. radiopharmaceutical injected into the body.
Radionuclide imaging currently includes the Radionuclide imaging currently includes the
following: following:
• a) scanning,
​​
• a) scanning,
​​
• b) scintigraphy with the use of gamma camera, • b) scintigraphy with the use of gamma camera,
• c) single-photon emission tomography and two-• c) single-photon emission tomography and two-
photon positron emission tomography (PET).photon positron emission tomography (PET).

13. Scanning - method visualization of organs and Scanning - method visualization of organs and
tissues by moving over the body of the scintillation tissues by moving over the body of the scintillation
detector. The device is conducting a study called detector. The device is conducting a study called
the scanner. The main drawback - the long the scanner. The main drawback - the long
duration of the study.duration of the study.

14. Scintigraphy. Method of imaging the spatial
distribution in organ of RFh and photon detection
with a scintillation detector or detectors. The method
makes it possible to evaluate the morphological and
functional state of the body. Scintigraphy - is
currently the main method of radionuclide imaging in
the clinic.

15. Gamma radiation from the body
of the patient is recorded by the
detector gamma camera and
computer after processing the
obtained information is
converted into a functional
image of the investigated body.

16. There are several types of scintigraphy.There are several types of scintigraphy.
Static planar scintigraphy Static planar scintigraphy. The simplest type of . The simplest type of
scintigraphy. After the introduction of RPh, registration its scintigraphy. After the introduction of RPh, registration its
distribution in the target organ by fixed detector. Determine distribution in the target organ by fixed detector. Determine
the shape, size and nature of the organ contours, and the shape, size and nature of the organ contours, and
most importantly, areas of abnormal accumulation indicator most importantly, areas of abnormal accumulation indicator
- high or low ("hot" or "cold" lesions). The method is - high or low ("hot" or "cold" lesions). The method is
applicable for the detection of tumor lesions in parenchymal applicable for the detection of tumor lesions in parenchymal
organs.organs.

17. Scintigraphy result of the
healthy liver thyrotoxic adenoma, hot node

18. Whole-body scintigraphyWhole-body scintigraphy. Variant static . Variant static
scintigraphy, however, here the table with the scintigraphy, however, here the table with the
patient or the detector are moved in a horizontal patient or the detector are moved in a horizontal
plane, which allows to detect of photons from all plane, which allows to detect of photons from all
Rph tracers of organism or a part of it. Widely used Rph tracers of organism or a part of it. Widely used
in the study of skeletal - in the study of skeletal - bone scintigraphy bone scintigraphy to to
identify multiple lesions pathological process, such identify multiple lesions pathological process, such
as searching for metastases.as searching for metastases.

19. metastases in bone

20. arthrosis

21. Dynamic scintigraphy. In contrast to the static, here, a series
of scintigrams with a certain time interval. This allows, in
addition to anatomical characteristics, to study organs
function ( eg. excretory function of the liver, the filtration and
excretory function of the kidneys, etc).

22. Immunoscintigraphy - imaging of tumors by
monoclonal antibodies with RPh are obtained by
immunization of animals extracts antigens from
remote malignant tumors. Sufficiently accurate
method for the diagnosis of malignancy.

23. Single photon emission computed tomography (SPECT
tomoscintigraphy) - registration of photons RPh of the
examined organ by using one, two or three detectors rotate
around the patient's body for some orbit (circular, elliptical, or
difficult-adaptive). The number of slices obtained from 32 to
128, slice thickness of 4 to 10 mm, reconstruction is possible
in different projections. This allows not only the anatomical
and topographical characteristics of the organ, but also
allows to study the biochemical, physiological, and transport
processes. Used for the diagnosis of volumetric formations
and vascular disorders of the brain, for the early detection of
pulmonary embolism, coronary artery disease.

24. Slice images
accumulation
Of RPh

25. Positron emission tomography (PET) - a method of nuclear medicine based
on the use of ultra-short-lived radiopharmaceuticals labeled with positron
emitters - 15O, 13N, 11C, 18F-FDG. T- aff. these drugs is 2, 10, 20.4 and
110 minutes. Sensitivity of the method is fantastic. PET allows us to
conclude the change rate of glucose labeled with C11 in the "eye center" of
the brain when you open the eyes, it is possible to detect changes at the
thinking process, and even to determine the so-called "Soul". PET enables
the study of functional changes and ability to live of tissue at the molecular
level, such as glucose metabolism, oxygen utilization, assessment of blood
flow and perfusion assessment . As well as functional changes precede
morphological, cellular metabolism study provides an opportunity to
diagnose a number of diseases earlier than with CT and MRI.

26. PET CT

27. Essentially this is the only method to evaluate the metabolic processes
in vivo. The method is used in cardiology for the study of perfusion and
blood flow in the myocardium with coronary artery disease, to determine
the viability of the myocardium after myocardial infarction; neurology for
the detection of epileptogenic foci in the diagnosis of various types of
dementia , in oncology for the diagnosis and staging of brain tumors,
lung, breast, colon, for evaluating chemotherapy for detecting tumor
recurrence. The disadvantage of this method is that its use is possible
only with the cyclotron, the radiochemical laboratory for short-lived
nuclides, positron tomography and computer information processing,
which is very expensive and cumbersome.

28. Thank you for attantion!