Contrast media 1
Radiographic Contrast
Media
RAD TECH 255
SPECIAL PROCEDURES
MERRILLS VOL2
Subject Contrast
• Range of differences in
the intensity of the xray beam, after it has
been attenuated by
the subject (patient).
Low Subject Contrast
What can be done to attain medical information•
see the difference between muscle, organs or vessels
Define and outline –
organ structure and function
Contrast media
• Defines subtle differences in subject contrast
• Increases atomic number of area injected
• Results in a SHORTER scale of subject contrast
Purpose of Contrast Media
• To enhance subject contrast or
render high subject contrast in a
tissue that normally has low subject
contrast.
Atomic Number
• Fat = 6.46
• Water = 7.51
• Muscle = 7.64
• Bone = 12.31
Radiographic Contrast : Influenced by…
• Radiation
Quality (KVP)
• Film Contrast
• Radiographic
object (Patient)
KVP
• TYPE OF CONTRAST USED DETERMINES KVP RANGE
BARIUM
IODINES
90 – 120 kVp
70 – 80 kVp
(Ionic / Nonionic
Water or Oil)
INJECTABLE
CONTRAST MEDIA
for RT 255 procedures
INVASIVE PROCEDURES
The “o-grams”
ALWAYS TAKE
A “SCOUT”
BEFORE CONTRAST
INJECTION
√
PATHOLOGY
√ TECHNIQUE
√ PREP & PRIOR CONTRAST
√ POSITIONING
SPECIAL “o-grams”
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Venogram
Arthrogram
Sialogram
Myelogram
Arteriogram
Angiogram
Galactogram
Hystersalpingogram…….. etc
CONTRAST INJECTION
DOUBLE CONTRAST WITH IODINE HIP Arthorgram
To check fertility
LYMPHANGIOGRAM
Galactography - Breast Duct
Cerebral Angiogram
SPECIAL PROCEDURES
ARE INVASIVE
ALWAYS GET PATIENT’S HISTORY
AND CONSENT BEFORE
BEGINNING
OR GIVING ANY CONTRAST
MEDIA
CONSENTS
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SIGNED AND WITNESSED
AFTER PROCEDURE HAS BEEN EXPLAINED
CHECK DEPARTMENT PROTOCOL
WHO’S RESPONSIBLE ??????
CONSENTS
• ASSAULT
verbal threat of harm
• BATTERY
Unlawful touching - unauthorized treatment
“X-RAY” TAKEN ON WRONG PATIENT
• FALSE IMPRISONMENT
Restraints require permission
from patient or authorized person
BLOOD WORK
LAB TESTS to check function of kidneys prior to
injection of contrast
•
WATCH THE UPPER LIMITS
• BUN = BLOOD UREA NITROGEN
• Merrills pg 214 range is 8 to 25
pg 242 range is 10 - 20
always check with RAD when level above 20
• CREATININE levels range:
• pg 214 (0.6 - 1.5) pg 242 (0.05 - 1.2)
always check with RAD when level above 1.2
• Indicates function of kidneys
• Diseases / dehydration / kidney failure
EGFR (new test)
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Estimated
Glomerular
Filtration
Rate
• More advanced test for
• CREATININE levels
Review of Contrast Agents
Types of Contrast
Routes of Adminstration
Chemical Components
Contrast Media changes the density of
the organs
Therefore changing
the
Subject contrast
will change the
Radiographic
contrast and film
contrast
May need to
INCREASE
TECHNIQUE FROM
SCOUT IMAGE
Contrast Media (review)
• Negative contrast
• (AIR OR CO2)
• Positive contrast
• (all others)
• Radiolucent
• Radiopaque
• Low atomic # material
• High atomic # material
• Black on film
• White on film
Types of Contrast Media
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Radiolucentnegative contrast agent
x-rays easily penetrate
areas- appear dark on films
Negative Contrast Media
• Air and gas
• complications
• emboli-air pockets in
vessels
• lack of oxygen
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Radiopaquepositive contrast agentabsorbs x-rays
appears light
Positive Contrast Agents
• BARIUM
• IODINES
Both + & - can be used in
same study
2 BASIC TYPES
OF CONTRAST material
• BARUIM Z# 56
• NON WATER SOLUABLE
• GI TRACT ONLY
INGESTED OR RECTALLY
• KVP 90 – 120*
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IODINE Z# 53
WATER SOLUABLE
POWDER
LIQUID
INTRAVENOUS OR
Intrathecal
GI TRACT
Also OIL based
KVP BELOW 90*
Methods of Administration
of Contrast Material
• INGESTED
– (ORAL)
• RETROGRADE
– AGAINST NORMAL FLOW
• INTRATHECAL
– Spinal canal
• PARENTERAL (IV, Intrathecal)
– Injecting into bloodstream
– (anything other than oral)
Contrast media for
SPECIAL PROCEDURES
Diagnostic agents
that are injected into
• Circulatory System, Joint Spaces, Ducts
• Body orifices/organs: uterus, breast,
salivary & lymph glands
BARIUM – a review
BARUIM SULFATE
Not used in Special Procedures
Barium Sulfate
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High atomic number
Not soluble in water
Used to coat the lining of organs
Supplied in different thicknesses
Used
– Esophogram, UGI, Small Bowel,Lower GI or
BE
Ba ADVERSE REACTIONS
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BARIUM INERT
SUSPENSION MAY CAUSE ALLERGY
OCG TABLETS (IODINE) ALLERGY
AFTER EXAM – MAY SOLIDIFY DIFFICULT TO
EVACUATE
• INCREASE FLUIDS, MILD LAXATIVE
• EXTRAVASATION OF CONTRAST INTO
PERITONEUM
Extravasation of BA in abd
Ingested CONTRAST
Gastrografin or Hypaque
• High atomic #
– Close to iodine
• Water soluble
• Similar usage as Barium
GASTROGRAFIN
Adverse Reactions
• Water soluble, safe in the abdominal
cavity
–Safe to use if perforation is suspected
• Very harmful to the lung tissue
–Do not use if aspiration is possible
Gastro – Pathology present
• Bowel
• Obstruction
• Note contrast
• Seen in kidneys
as well
IODINE
IONIC OR NON IONIC
WATER OR OIL BASE
IODINATED CONTRAST
iodine z # 53
• WATER BASED
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INJECTED
VESSELLS/DUCTS
INGESTED
Organ function/flow
OPEN WOUNDS
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OIL BASED
INJECTED
NEVER VESSELLS
ONLY DUCTS
NOT INGESTED
OPEN WOUNDS
INJECTION OF IODINE
into Vessels
• ALWAYS A WATER
BASED IODINATED
COMPOUND
• IONIC VS
• NON IONIC
• CONTRAST
• BOLUS INJECTION
• INFUSION DRIP
• 50 -70 % CONCENTRATE
IODINE WATER BASED CONTRAST
• IONIC
• LESS $$$
• NON IONIC
• MORE $$$
• MORE REACTIONS
• LESS REACTIONS
CONTRAST MEDIA
IODINE
is either: IONIC or NON-IONIC
• Osmolarity
• # Of Particles (Cations + And Anions -)
– In Solution Per Kilogram Of Water
• High Osmolarity
– =more Cations And Anions
• Can Upset Homeostasis
• Nonionic Have No Charged Particles
Contrast Agents
IONIC
• High Osmolality
(Higher risk of
complications)
NON-IONIC
• Low Osmolality
(Lower risk of
complications)
• Gadodiamide
(Omniscan)
– Iodixanol (Visipaque)
– Diatrizoate sodium
(Hypaque)
– Iopamidol (Isovue)
– Iopromide (Ultravist)
– Iothalamate
– Ioversol (Optiray)
meglumine (Conray)
• Less money
• More reactions
• More money
• Less reactions
OIL – BASED
IODINE
CONTAST
Instilled in ORGAN
Oil Based Iodine
• Fatty Acids
• Insoluble in water
– White on the radiograph = Radiopaque
• Uses
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Broncography (lungs)
Tear ducts
Salivary glands
Lymphatic system
Hysterrosalpingogram
Galactography (breast ducts)
• FAT EMBOLUS IF IT GETS INTO
•
BLOOD VESSEL
Newer
Contrast Agents Balance
Safety and Visualization