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Day 1
Dr. Zbigniew Serafin, MD, PhD
[email protected]
The coursework of Radiology and Diagnostic Imaging includes 90 hours of tutorials and seminars. Tutorials
and seminars are prepared in a week cycle. The course is divided into Core Radiology on 4 th year and OrganBased Radiology on 5th year. Core Radiology ends with a credit with grade. Organ-Based Radiology curriculum
ends with a final test exam. The final test will be timed in the schedule of the session.
Basic textbooks:

Gibson R: Essential Medical Imaging. Cambridge University Press, 2009.

Weissleder R: Primer of Diagnostic Imaging. 4th ed, Mosby Elsevier, 2007.

Moeller T.B., Reif E.: Pocket Atlas of Sectional Anatomy, Computed Tomography and Magnetic
Resonance Imaging, Vol. 1-3. Thieme Verlag, 2007.
Additional textbooks:

Daffner R: Clinical Radiology. Lippincott Williams & Wilkins, 2007.

Vilensky J: Medical Imaging of Normal and Pathologic Anatomy. WB Saunders Company, 2010.

Suetens P: Fundamentals of Medical Imaging, Cambridge University Press, 2009.
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Requirements and crediting
1.
The classes are obligatory. In the case of the illness a sick leave has to be delivered. Other absences due to
important reason must be documented. In the case of the absence the respective topics have to be credited.
Students presenting with unjustified and uncredited absences will not be credited and allowed for the final
exam.
2.
Each Student is obliged to come for the classes on time. Delayed Students can enter the class only if the
time of delaying does not exceed 15 minutes from the moment the classes have been started.
3.
Students are obliged to prepare the respective part of the material for each classes. Topics are listed in
Syllabus. The knowledge and the activity of each Student will be noted. In the case of a negative note the
Student has to pass the respective topics till the end of the course.
4.
Students are obligated to clean up after themselves. Eating, drinking, and using mobile phones during the
labs are prohibited. Any accidents, injuries and other emergencies must be immediately reported to the
Tutor.
5.
Students are obliged to follow ethical rules as well as the rules of deontology, especially when attending live
cases.
6.
Students are obliged to observe copyright and respect the right of intellectual property of electronic
publications as well as printed collections (published works, master’s and bachelor’s dissertations, course
books etc.)
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Interim test

The test consists of multiple choice questions (only
one answer correct).

Students who failed the test are obliged to retake
the test.

The final scores of are not changeable.

The scores of the retake will be confirmed by a
signature in the Student Book as positive score but
not as the mean of these two.


In the case of an absence at the test a sick leave has
to be submitted to the examiner within three days
after the test.
The test will be assessed according to the following
scores:
Note
Score
Unsatisfactory (2)
< 60%
Satisfactory (3)
60-64%
Fairly Good (3,5)
65-69
Good (4)
70-79
Very Good (4,5)
80-89
Excellent (5)
≥ 90%
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Plan of classes
seminars + exercises = 30 h
8:00 – 12:30
Monday – radiography.
2. Tuesday – computed tomography.
3. Wednesday – magnetic resonance imaging.
4. Thursday – ultrasonography.
5. Friday – management in radiology, TEST.
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Aims of classes
to provide basic knowledge on:

physical and technical principles of medical imaging,

cross-sectional anatomy,

indications and contraindications imaging,

radiation safety.
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Diagnostic imaging

radiography

fluoroscopy

invasive angiography

CT

MRI

ultrasound

nuclear imaging (scintigraphy, PET, SPECT)

coronarography, ventriculography, electrophysiology,

echocardiography

molecular imaging

optical iamging

interventional radiology
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organ-based
approach
modality-based
approach
neuroimaging
radiography
cardiovascular imaging
CT
MSK imaging
MRI
GI imaging
ultrasound
uroimaging
interventional
respiratory imaging
nuclear imaging
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1895 – invention of X-rays by W.K. Roentgen
1895 – first X-ray of the human
1896 – first radiation in juries
1896 – Becquerel discovers radioactivity
1905 – the first English book on Chest Radiography is published
1918 – Eastman introduces radiographic film
1934 – Joliot and Curie discover artificial radionuclides
1950's – development of the image intensifier and X-ray television
1956 – medical use of ultrasound starts in Poland.
1962 – emission reconstruction tomography (later SPECT and PET)
1972 – invention of CT by Hounsfield at EMI
1977 – first human MRI images.
1980's – Fuji develops CR technology.
1984 – MRI cleared for commercial use by FDA
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November 8, 1895
Roentgen’s experimental apparatus (Crookes tube)
that led to the discovery of the new radiation.
Roentgen demonstrated that the radiation was
not due to charged particles, but due to an as yet
unknown source, hence “x” radiation or “x-rays.”
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http://www.learningradiology.com
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Bertha Roentgen (1895)
„Über eine neue Art von Strahlen”
http://www.learningradiology.com
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Radiation
emission or emission and propagation
of energy in the form of particles or
waves.
Ionizing radiation
radiation having sufficient energy to
ionize an atom
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Interaction of X-rays with matter = sources of attenuation
The attenuation that results due to the interaction between penetrating
radiation and matter is not a simple process. A single interaction event
between a primary x-ray photon and a particle of matter does not usually
result in the photon changing to some other form of energy and effectively
disappearing. Several interaction events are usually involved and the total
attenuation is the sum of the attenuation due to different types of
interactions.
These interactions include
the photoelectric effect, scattering,
and pair production
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 Photoelectric absorption of x-rays occurs when the x-ray photon is
absorbed, resulting in the ejection of electrons from the outer shell of the
atom, and hence the ionization of the atom. Subsequently, the ionized
atom returns to the neutral state with the emission of an x-ray
characteristic of the atom. This subsequent emission of lower energy
photons is generally absorbed and does not contribute to (or hinder) the
image making process. Photoelectron absorption is the dominant process
for x-ray absorption up to energies of about 500 KeV. Photoelectron
absorption is also dominant for atoms of high atomic numbers.
Photoelectric effect is a lowenergy phenomenon and is the
most important for image
acquisition and radiation safety
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 Compton scattering occurs when the incident x-ray photon is deflected
from its original path by an interaction with an electron. The electron gains
energy and is ejected from its orbital position. The x-ray photon loses
energy due to the interaction but continues to travel through the material
along an altered path. Since the scattered x-ray photon has less energy, it,
therefore, has a longer wavelength than the incident photon. The event is
also known as incoherent scattering because the photon energy change
resulting from an interaction is not always orderly and consistent.
Compton scattering is the most
probable interaction of gamma
rays and high energy X-rays with
atoms in living beings. The
phenomenon responds for the
image noise and health hazard
related to imaging.
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 Thomson scattering (Rayleigh, coherent, or classical scattering), occurs
when the x-ray photon interacts with the whole atom so that the photon is
scattered with no change in internal energy to the scattering atom, nor to
the x-ray photon. Thomson scattering is never more than a minor
contributor to the absorption coefficient. The scattering occurs without the
loss of energy. Scattering is mainly in the forward direction.
Thomson scattering is related to 5-10%
of all tissue interactions with X-rays.
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 Pair production can occur when the x-ray photon energy is greater than
1.02 MeV, but really only becomes significant at energies around 10 MeV.
Pair production occurs when an electron and positron are created with the
annihilation of the x-ray photon. Positrons are very short lived and
disappear (positron annihilation) with the formation of two photons of 0.51
MeV energy. Pair production is of particular importance when high-energy
photons pass through materials of a high atomic number.
Pair production is used in PET
imaging.
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X-rays are produced when energetic electrons strike a metal target. The X-ray source
consists of an evacuated tube containing a cathode, from which the electrons are emitted,
and an anode, which supports the target material where the X-rays are produced. Only
about 1 per cent of the energy used is emitted as X-rays – the remainder is dissipated as
heat in the anode. In most systems the anode is rotated so that the electrons strike only a
small portion at any one time and the rest of the anode can cool. The X-rays are emitted
from the tube via a radio-translucent exit window.
Basic X-ray production
 electron source – cathode
 target – anode
 evacuated path for the e-s to
travel through – x-ray tube insert
 external energy source to
accelerate the e-s – generator
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Electron interactions with the anode produce:
1. Heat – the kinetic energy (KE) of the electron deposits its energy in the
form of heat (~99%)
2. X-rays production
 Bremsstrahlung
– continuous energy spectrum
 characteristic X-rays – discrete energies
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Each part of the X-ray tube is essential to create the environment
necessary to produce x-rays via:
 Bremsstrahlung
 Characteristic x-rays
The potential difference (kVp), tube current (mA), and exposure time (s)
are selectable parameters to determine the x-ray spectrum
characteristics (quality and quantity of x-ray photons
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X-ray tube filtration:
 absorbs low-energy x-rays
 inherent filtration - glass or metal insert at x-ray tube window
 added filtration (Al, Cu, plastic, Mo, Rh)
 reduces patient dose
 increases x-ray beam quality
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X-ray tube collimation:
 collimators adjust size and shape of
x-ray beam
 reduces patient dose
 improves image contrast
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Other elements of X-ray tube:
 HF generator – converts AC to DC and
increases the voltage
 operator console – exposure time settings
 phototimers – AEC system
 Bucky grid
 patient’s table
 detector
80 kW generator can produce 800 mA at 100 kVp
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Other elements of X-ray tube:
 HF generator – converts AC to DC and
increases the voltage
 operator console – exposure time settings
 phototimers – AEC system
 Bucky grid
 patient’s table
 detector
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Other elements of X-ray tube:
 HF generator – converts AC to DC and
increases the voltage
 operator console – exposure time settings
 phototimers – AEC system
 Bucky grid
 patient’s table
 detector (casette)
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Limitations of film-screen radiography:
 limited dynamic range (only about
two orders of magnitude)
 difficult multiplication of the image
 waiting time for the result
 limited processing capabilities
 need for additional personnel
 environmental pollution
 QA monitoring is time consuming
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Digital radiography:
Computed Radiography (CR)
 phosphor-based storage plate
 chemical storage (oxidation of Eu)
 laser scanning, light erasure
Digital Radiography (DR)
 flat-panel detectors
 Csl scintillator and photo-diodes
 better dynamic range, quantum efficiency
Charge Coupled Device (CCD)
 phosphor screen, fiberoptic cables, CCD sensor
 good sensitivity, low noise
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EXERCISE
What can we imagine on plain films?
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skeleton
high-density foreign bodies
calcifications
tubular structures
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What can we imagine on plain films?
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skeleton
high-density foreign bodies
calcifications
tubular structures
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What can we imagine on plain films?
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skeleton
high-density foreign bodies
calcifications
tubular structures
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What can we imagine on plain films?
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skeleton
high-density foreign bodies
calcifications
tubular structures
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What can we imagine on plain films?
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skeleton
high-density foreign bodies
calcifications
tubular structures
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congenital
trauma
inflammation
neoplasms
cardiovascular
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congenital
trauma
inflammation
neoplasms
cardiovascular
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congenital
trauma
inflammation
neoplasms
cardiovascular
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congenital
trauma
inflammation
neoplasms
cardiovascular
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congenital
trauma
inflammation
neoplasms
cardiovascular
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CNS
skeleton
cardiovascular
respiratory
GI
urinary
reproductive
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CNS
skeleton
cardiovascular
respiratory
GI
urinary
reproductive
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CNS
skeleton
cardiovascular
respiratory
GI
urinary
reproductive
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CNS
skeleton
cardiovascular
respiratory
GI
urinary
reproductive
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CNS
skeleton
cardiovascular
respiratory
GI
urinary
reproductive
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CNS
skeleton
cardiovascular
respiratory
GI
urinary
reproductive
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CNS
skeleton
cardiovascular
respiratory
GI
urinary
reproductive
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 ???
 infertility
 neoplasms
 cataracts (progressive lens opacity)
 heritable mutations
 marrow stimulation / depletion
 contrast media
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 ???
 pregnancy
 ataxia teleangiectasia
 Bloom syndrome
 clinically unstable patient
 obesity
 lacking indications!!!
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 ???
 infertility
 neoplasms
 cataracts (progressive lens opacity)
 heritable mutations
 marrow stimulation / depletion
 contrast media
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 ???
 infertility
 neoplasms
 cataracts (progressive lens opacity)
 heritable mutations
 marrow stimulation / depletion
 contrast media
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Any substance that renders an organ or structure more visible than is possible
without its addition. CM allows visualization of structures that can not be seen
well or at all under normal circumstances
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Contrast media is needed because:
 Soft tissue has a low absorption / interaction ratio
 Absorption is dependent on
• atomic number
• atomic density
• electron density
• part thickness
• K-shell binding energy (K-edge)
Negative CM
 air
 oxygen
 carbon dioxide
Positive CM
 barium
 iodine
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Non-water-soluble CM
 absorbed – oily &/or viscous (Lipiodol)
 not absorbed – inert (Barium)
Water-soluble
 non-injectible – oral
 injectible – intravenous
Direct application
 barium studies
 angiography
Water-soluble
 non-injectible – oral
 injectible – intravenous
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Adverse reactions:
 anaphylactoid
• urticaria
• facial / laryngeal edema
• bronchospasm
• circulatory collapse
 non-anaphylactoid
• nausea / vomiting
• cardiac arrhythmia
• pulmonary edema
• seizure
• renal failure
 delayed
• fever, chills, rush
• nausea, vomiting
• headache
DEATH:
1/40.000 – 1/200.000 patients
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Clinical applications:
 vascular imaging
 inflammation
 neoplasms
 GI tract imaging
 urinary tract imaging
 trauma
 „tissue differentiation”
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http://www.learningradiology.com
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Clinical applications:
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GI tract imaging
intraoperative image-guidance
evacuation of foreign bodies
differentiation of pulmonary nodules
ERCP
--------------------
Flat-panel detector
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Whose that hand? (1896)
lime / mercury / petroleum
http://www.learningradiology.com
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Digital Subtracted Angiography
(DSA)
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Digital Subtracted Angiography
(DSA)
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Digital Subtracted Angiography
(DSA)
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Additional processing features of DSA




last image hold
road mapping
pixel shifting
3D DSA
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Clinical applications:
 vascular imaging
• arteriography
• venography
• lymphography ?
 (endovascular procedures – interventional radiology)
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arteriography
 vascular malformations
 atherosclerosis
 embolism
 trauma
 neoplasms
 fistulae
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arteriography
 vascular malformations
 atherosclerosis
 embolism
 trauma
 neoplasms
 fistulae
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arteriography
 vascular malformations
 atherosclerosis
 embolism
 trauma
 neoplasms
 fistulae
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arteriography
 vascular malformations
 atherosclerosis
 embolism
 trauma
 neoplasms
 fistulae
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arteriography
 vascular malformations
 atherosclerosis
 embolism
 trauma
 neoplasms
 fistulae
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arteriography
 vascular malformations
 atherosclerosis
 embolism
 trauma
 neoplasms
 fistulae
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venography
 deep vein thrombosis
 pulmonary embolism
 vascular malformations
 vein insufficiency
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venography
 deep vein thrombosis
 pulmonary embolism
 vascular malformations
 vein insufficiency
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venography
 deep vein thrombosis
 pulmonary embolism
 vascular malformations
 vein insufficiency
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venography
 deep vein thrombosis
 pulmonary embolism
 vascular malformations
 vein insufficiency
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phlebography
 lymphatic edema
 metastases
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
previous severe reaction to contrast media

impaired blood clotting factors

inability to undergo surgical procedure

impaired renal function ?
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puncture site
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infection
hematoma
nerve injury (brachial plexus)
arteriography
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vasospasm
dissection, stenosis, occlusion
perforation, hemorrhage
release of atheroma, embolism
stroke, AKI, mesenteric ischemia, limb ischemia
DEATH
venography
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phlebitis, thrombophlebitis
dislodging a clot, embolism
contrast media
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