Lesson 1 and 2: Introduction to Interventional Radiology Flashcards
this involves the use of needles and contrast media to enter and highlight an artery
angiography
it was the first interventional radiology procedure performed in the 1930s
angiography
this involves entering select coronary arteries through an artery of the arms
transbrachial selective coronary angiography
in the 1960s, he pioneered transbrachial selective coronary angiography
Mason Jones
this involves entering an artery in the thigh
transfemoral angiography
it was developed in the 1960s to examine selective visceral, heart, and head arteries
transfemoral angiography
he introduced coronary angiography
Melvin Judkins
he introduced visceral angiography
Charles Dotter
he described a method of arterial access in which a catheter was used
1953 Sven Ivar Seldinger
an 18-gauge hollow needle with a stylet
seldinger needle
it is most often used for arterial access in angiography
common femoral artery
location of the common femoral artery
pulse in the groin below the inguinal ligament, which passes between the symphysis pubis and the anterior superior iliac spine (ASIS)
needle gauge size for olive
14
needle gauge size for orange
15
needle gauge size for purple
16
needle gauge size for pink
18
needle gauge size for brown
19
needle gauge size for yellow
20
needle gauge size for green
21
needle gauge size for black
22
needle gauge size for sky blue
23
needle gauge size for blue
25
needle gauge size for gray
27
needle gauge size for lavender
30
this allows the radiologist to position the catheter within the vascular network
guidewires
these are fabricated of stainless steel and contain an inner core wire that is tapered at the end to a soft, flexible tip
guidewires
it allows the safe introduction of the catheter into the vessels
guidewires
a variation of the tip configuration that was initially designed for use in atherosclerosis vessels filled with plaque
J-tip
similar to guidewires, these are designed in many different shapes and sizes
catheters
unit for catheter diameter
French (Fr) size
3 Fr is equivalent to _____ in diameter
1 mm
it catheter shape is used for the femoral approach to the brachiocephalic vessels
H1 or headhunter tip
he designed the H1 or headhunter tip
Vincent Hinck
it catheter shape is highly curved for approach to sharply angled vessels
simmons catheter
this catheter shape was also designed for cerebral angiography but was later adopted for visceral angiography
simmons catheter
it has an angled tip joined to a gentle curve and is used for introduction into celiac, renal, and mesenteric arteries
C2 or cobra catheter
these have side holes for ejecting contrast media into a compact bolus
pigtail catheter
purpose of catheters with side holes (pigtail catheter)
it help reduce a possible whiplash effect
it has low concentration of ions (low osmolality) which results to reduced physiologic problems and adverse reactions for patients undergoing angiographic injection
non-ionic contrast media
most common complication associated with catheter angiography
continued bleeding at the puncture site
other risk factors of angiography
related kidney failure
procedure room
size: not less than 20 ft. along any walls and not less than 500 ft^2
should be finished with consideration for maintaining a clean and sterile environment
importance of procedure room size
to accommodate the quantity of equipment required and the large number of people involved in most procedures
control room
size: large, perhaps 100 ft^2
this room should communicate directly with the viewing area
it should have positive air pressure and filtered incoming air
personnel
a radiographer who specializes in IR requires additional skills
two or three radiographers may be present in the IR suite, as well as the interventional radiologists and a radiology nurse, who carefully monitors the patient
during the procedure that require the patient to be highly medicated, an anesthesiologist also may be present
interventional radiology x-ray tube: focal spot size
1.0 mm or 0.3 mm
large for heat load, small for magnification radiography
interventional radiology x-ray tube: disc size
15 cm in diameter, 5 cm thick
to accommodate heat load
interventional radiology x-ray tube: power rating
80 kW
for rapid sequence, serial radiography
interventional radiology x-ray tube: anode heat capacity
1 MHU (mega heat unit)
to accommodate heat load
formula for magnetic factor
M = SID / SID - OID or
M= SID/SOD
formula for focal spot blur
focal spot blur = (effective focal spot) OID / SOD
this means blood vessel
angio
the radiological study of blood vessels in the body after the introduction of iodinated contrast media
angiography
it is simply a technique by which bone structures images are subtracted or canceled out from a film of bones plus opacified vessels, leaving an unobscured image of the vessels
subtraction
the acquisition of digital fluoroscopic images combined with injection of contrast material and real-time subtraction of pre- and post-contrast images to perform angiography
digital subtraction angiography
a Portuguese neurologists developed the technique of contrast x-ray cerebral angiography to diagnose diseases such as tumors and arteriovenous malformations
1927 Egas Moniz
the year Egas Moniz won the nobel prize
1949
a Dutch radiologist, he was the first to proposed the idea of subtraction images in 1935, when he was able to produce subtracted images using plain films
Ziedes des Plantes
with its introduction in the 1953, the procedure became safer as no sharp devices need to remain inside the vascular lumen
seldinger technique
photographic method used to eliminate unwanted images
no addition of information, only purpose is to make diagnostically important information to see
conventional subtraction technique
this was first described by a Dutch radiologist, Zeides des Plantes, in 1935
conventional subtraction technique
three conditions for conventional subtraction technique
scout film
angiogram film-contrast
no motion of head
principles of subtraction
scout film shows the structural details of the skill and the adjacent soft tissue
angiogram film shows exactly the same anatomic details, if the patient does not move, plus the opacified blood vessels
if all the information in the scout film could be subtracted from the angiogram, only the opacified vessel pattern would remain visible
it can change films – 6/s or 1/5s
two of these changers can be coupled electronically and mechanically and will operate out of phase or synchronously with each other
radiographs in two planes simultaneously-one mounted vertically and other horizontally
AOT changer
a large steel container, inside the container are arranged a number of strong wire separators
loading magzine
a shallow, polished metal container
lid is a sliding section in a side which can be pushed down by firm finger pressure and is retained by central spring located catch
receiving cassette
mechanically easier to wind roll films
roll film changer
this is a complex electronic device that receives the image-forming x-ray beam and converts it into a visible-light image of high intensity
image-intensifier tube
it converts the pattern of the x-ray beam into a bright visible-light image
image-intensifier tube
it contains the tube component
glass or metal envelope
this provides structural support but more importantly maintains vacuum
glass or metal envelope
it protects the tube from rough handling and breakage
glass ot metal envelope
when an x-ray interacts with this, its energy is converted into visible light; this is similar to the effect of radiographic intensifying screens
input phosphor
component of input phosphor
cesium iodide (CsI)
they are grown as tiny needles and are tightly packed in a layer of approximately 300 µm
each crystal is approximately 5 µm in diameter
this results in micro-light-pipes with little dispersion and improved spatial resolution
cesium iodide (CsI)
another active element of the image-intensifier tube, which is bonded directly to the input phosphor with a thin transparent adhesive layer
photocathode
it is a thin metal layer usually composed of cesium and antimony compound that responds to stimulation of input phosphor light by the emission of electrons
photocathode
this emits electrons when illuminated by the input phosphor
photocathode
this is similar to thermionic emission, which refers to electron emission that follows heat stimulation
photoemission
it is electron emission that follows light stimulation
photoemission
the site where accelerated electrons interact and produce light
output phosphor
it is located at the other side of the anode
output phosphor
component of output phosphor
zinc cadmium sulfide
a technique by which bone structure images are subtracted, or canceled out, from a film of bones and opacified vessels, leaving an unobscured image of the vessels
photographic subtraction technique
this technique can be applied in all forms of angiography, wherever the vessels are superimposed in bone structures
photographic subtraction technique
he introduced the photographic subtraction technique
Zeides des Plantes
year when angiography was first successively used for the human body
1923
a swedish doctor who pioneered the seldinger technique, which laid down the foundation of interventional radiology
1953 Sven Ivar Seldinger
he first proposed the idea of interventional radiology
1963 Charles Dotter
he opened a new era of percutaneous angioplasty through accidental operation, marking the formation of interventional radiology
1964 Chrales Dotter
importance of interventional radiology in medicine
diagnose and treat patients using the least invasive techniques currently available in order to minimize risk to the patient and improve health outcome
these procedures have less risk, less pain, and less recovery time in comparison to open surgery
it is now a therapeutic and diagnostic specialty that comprises a wide range of minimally invasive image-guided therapeutic procedures as well as invasive diagnostic imaging techniques
repair or unblocking of blood vessels
angioplasty
a small mesh tube that treat narrow or weak arteries
stenting
dissolving blood clots
thrombolysis
block blood flow to cancer cells
embolization
this is used to reduce nerve pain
radiofrequency ablation
biopsies
the studies of tissues
most common interventional radiology procedures
angiography
angioplasty/stent
chemoembolization
thrombolysis
biopsy
RF ablation
cryoablation
IVC filter
benefits of interventional radiology procedures
increased effectiveness
reduced complications
outpatient vs. inpatient stay
lower costs
less pain
quicker recovery time
risk of interventional radiology procedures
increased exposure to radiatiton
it is introduced by Ziedes des Plantes
photographic subtraction
this is a technique by which bone structure image is subtracted or cancelled out
from the film of bones and opacified vessels leaving an unobscured image of the vessels
photographic subtraction
purpose of subtraction in angiography and other specialized procedure
to fully define all vessels containing contrast material and at the same time eliminate the confusing overlying bone images
matching one image over another so that bony landmarks are precisely superimposed
registration
reverse tone duplicate of radiographic image, showing black changed to white and white to black
reversal film or mask film
film showing bone structures only, with no patient motion between it and subsequent contrast studies
zero film or scout film
radiographic image obtained with the contrast media induced in the patient
series film
the simplest method of photographic subtraction
first order subtraction
procedures of first order subtraction
take scout film
the scout film is reversed using contact printer to obtain the reversal mask film
take series film
finally register the reversal mask film and series film together with blank film to obtain the final film
the process cancel out bony structure and reveal the anatomy of interest which appears in black
the simplest zero film obtained in the first order subtraction is usually not the exact reversal of the density of the selected angiographic film
the imperfection can be corrected
second order subtraction
they developed the second order subtraction
Hanafee and Shinno
procedures of second order subtraction
take scout film
the scout film is reversed using contact printer to obtain the reversal mask film
take series film
the series film is reversed using contact printer to obtain the reversal film
register scout film and series reversal film together with a blank film to obtain the second mask film
finally register the mask film, series film, second mask film, and blank film to obtain the final film
based on digital fluoroscopy/fluorography systems, which are equipped with special software and display facilities
modern DSA system
this was developed to improved vessel contrast
digital subtraction angiography
it is a technique that uses a computer to subtract two images, obtained before and after contrast media is injected into the vessels of interest
digital subtraction angiography
the anatomical structures that are the same in the two images can be removed and the resulting image shows the vessels only
digital subtraction angiography
the image before the contrast agent is administered
mask film
it has two separate image memories, one for the mask and the other for the images with contrast medium
these two image memories are subtracted from one another arithmetically, and the result to an image processing and display unit
DSA processor
adjusts contrast and brightness
image processing
image processing parameters
remasking
pixel shifting
edge enhancement
landmarking
noise smoothing
correcting misregistered images
remasking
a process that is used to correct the inaccurate images during DSA
remasking
it diminishes what is blurry on the image in the monitor
pixel shifting
this enhances resolution of a certain display presented in the monitor
pixel shifting
edges of the vessels can be enhanced so that small details can be made more obvious
edge enhancement
it operates by reducing the statistical fluctuations in each pixel by averaging the pixel with its closest neighbor
noise smoothing
this help equalize image pixel
noise smoothing
the visual prominence of noise has been suppressed by averaging, but resolution is decreased
noise smoothing
this gives random variation of image brightness which causes the image to appear grainy
noise
noise =
decrease brightness
decreased resolution
this is useful for the placement of catheters and wires in complex and small vasculature
roadmapping
factors affecting image quality
resolution
contrast
brightness
image lag
distortion
the proves by which something is separated into its component part
resolution
this refers to the amount of detail which is observable
resolution
it may be formulated on the number of pairs of black and white lines on image forming or image recording device can demonstrate in a length of ___
resolutiion, 1 mm
it is determined by no. of vertical scan lines (e.g. 625)
vertical resolution
in recent years the manufacturers of radio diagnostic imaging equipment have developed this definition TV system which employ ___ or even more lines
1249
the ____ of the image on a TV screen clearly depends on the ____ of the original image focused onto the signal plate of the pick up tube
contrast
both ___ and ___ affects the contrast of a TV image
camera, monitor
this reduces contrast by a factor of approx. 0.8 and the monitor enhances by a factor of 2
vidicon camera
the term ___ and ___ are often used when describing the aspect of TV image
luminance, brightness
it can be defined as light emitted per unit area from a surface
luminance
unit for luminance
candela per square meter (cd/m^2)
this helps maintain the image intensifier exposure rate based on the subject’s thickness
automatic brightness control
it is critical to the patient dose and image quality
automatic brightness control
this monitors the light output from an area of the face of the image intensifier and it tries to maintain the signal travel within an approximate range of that output and adjust tube potential (kVP) and tube current (mA) according to predefined algorithm
automatic brightness control
it refers to control of x-ray exposure levels
automatic brightness control
if brightness is controlled by varying sensitivity the TV system, this terms is used
automatic gain control
it is fairly simple and inexpensive way to control image brightness
automatic gain control
the term used to describe inability of an imaging system to follow rapid changes in its input image
image lag
this occur in the image intensifier or in the optical coupling system which links its output phosphor to the signal plate of the TV pick up tube
distortion
indications for DSA
non traumatic subarachnoid hemorrhage (SAH)
arterial dissection or laceration
aneurysm
pseudoaneurysm
thrombosis
arterio-venous malformation (AVM)
arterio-venous fistula (AVF)
tumor vascularity
gastrointestinal bleed/uterine artery bleed
therapeutic
contraindications for DSA
poor renal reserve
allergic to contrast media
recent barium examination – abd. angio
a type of fluoroscopy technique used in interventional radiology to clearly visualize blood vessels in a bony or dense soft tissue environment
digital subtraction angiography
a fluoroscopic technique used extensively in interventional radiology for visualizing blood vessels
digital subtraction angiography
radiopaque structures such as bones are eliminated (subtracted) digitally from the image, thus allowing for an accurate depiction of the blood vessels
digital subtraction angiography
it is performed for diagnostic and therapeutic purposes of vessel visualization in the body
digital subtraction angiography
angiography is largely possible because of Seldinger technique for intravascular access
1953
digital subtraction angiography, whereby a pre-contrast image is acquired, then subtracted from subsequent post-contrast images, was made possible because of real-time refreshing of the resulting images
1970s
the development of DSA was a result of the research of medical physics groups at the University of Wisconsin, the University of Arizona and the Kinderklinik in Kiel, West Germany
early 1970s
the feasibility of DSA for human subjects was demonstrated
1978
prototype commercial DSA systems were introduced at the Universities of Arizona and Wisconsin, the Cleveland Clinic, and South Bay Hospital in Redondo Beach, California
1980
pre-procedural evaluation
presence of atherosclerotic disease (e.g. prior myocardial infarction)
diabetes
renal function status
medications
allergies and previous exposure to iodinated contrast media
prior surgical procedures, especially vascular
reports from previously performed angiograms, if any
review of any relevant vascular Imaging studies (e.g. pre-procedural CT)
angiogram
procedural technique
for every purpose, there is at least one technique, but common to them all is the application of DSA for visualization
this depends on the nature of the procedure and whether it was performed on an inpatient or outpatient basis
post procedural care
post procedural care:
patient should be immobilized for ___ to ___ hours and keep on ___ position, frequent observations should be done to look for ___, which is the commonest complications
4 to 6, puncture site hematoma
local complications (puncture site) of DSA
from the puncture site: commonest complication
thrombus formation: blood clot
local tissue damage
pseudoaneurysm: false aneurysm, pooling of blood at the artery walls
arteriovenous fistula: abnormal connection of arteries and veins
systemic complications of DSA
thromboembolism
air embolism
vessel dissection
contrast medicated nephrotoxicity
