Radiographic Contrast RTEC - A 2012 SUBJECT & FILM CONTRAST CONTRAST MEDIA

2 types of Radiographic “Contrast” Subject contrast patient Film contrast Inherent in equipment The BLACKS & WHITES ON THE FILM / IMAGE Two types of contrast Contrast defined as Range of density variations (differences from black to white) Subject And Film contrast

“Subject” Contrast

Subject Contrast Range of differences in the intensity of the x-ray beam After it has been attenuated by the subject.

SUBJECT CONTRAST Radiographic object - influenced by Atomic Number of object Density of object Thickness of object 5 materials seen on a radiograph, Gas/air, fat, soft tissue (muscle/organs), bone and metals Muscles is more dense that fat.

Atomic Number Fat = 6.46 Water = 7.51 Muscle = 7.64 Bone = 12.31 Basic estimate for atomic number of fat, water, muscle, and bone.

Tissue Subject Contrast Atomic # of object Density of object Thickness of object Higher atomic # = more attenuation Denser = more attenuation Thicker = more attenuation

PATHOLOGY Pleural Effusion Excessive fluid in lung More dense than air

Pneumothorax Lung collapses No tissue in space Easy to penetrate with x-ray photons The right lung is almost completely collapsed; vascular shadows can not be seen in this area (arrow).

Blunted angles on the chest xray indicating fluid.

Film Contrast AKA Radiographic Contrast

Radiographic Contrast influenced by: Radiation Quality (KVP) Film attributes Radiographic object (Patient) Radiation Quality (KVP)-lower range – more black to whites. Higher range there is a long scale of contrast Film Contrast Radiographic object (Patient)

What is good contrast ? High contrast (black and white) Low contrast (more shades of gray) Good contrast can not be defined because everyone’s eyes work differently. On left it is a narrow latititude Right has a wide latitude

RADIOGRAPHIC IMAGE Radiation Quality = kVp High kVp ↑ 80 Low contrast Lots shades of gray Long Scale Little differences in adjacent structures Low kVp ↓ 70 High contrast Black and White Short Scale Great differences in adjacent structures

Contrast changes with the use of a grid Less scatter radiation – shorter scale = “better contrast” With Grid No Grid

QUALITY – KVP A visible change in contrast will not be seen until kVp is changed 4-12 % kVp level change change in kVp 30-50 kVp 4-5 % 1-3 kVp 50-90 kVp 8-9 % 4-8 kVp 90-130 kVp 10-12 % 9-16 kVp

Scenario _____________________________________ Low subject contrast in the area of interest. You want to see the difference between muscle & fat & organs? What can be done to attain medical information and define organ structure and function? _____________________________________

Scenario USE CONTRAST MEDIA Low subject contrast in the area of interest. You want to see the difference between muscle & fat & organs? What can be done to attain medical information and define organ structure and function? USE CONTRAST MEDIA

Changing Subject Contrast with CONTRAST MEDIA

Barium has a higher z# more asorbtion of photons

INJECTING CONTRAST MEDIA INTO THE ARM SO THAT THE BODY PICKS UP THE CONTRAST WHEN IT IS FILTERED IN THE KIDNEYS.

Contrast Media changes the density of the organs 1) Use contrast media 2) Changes subject contrast 3) Changes radiographic (film contrast) Therefore changing the Subject contrast will change the Radiographic contrast and film contrast

Purpose of Contrast Media To enhance subject contrast or render high subject contrast In a tissue that normally has low subject contrast. Creates bigger differences in atomic number (z #’s) To enhance subject contrast or render high subject contrast in a tissue that normally has low subject contrast. (bigger differences in z#)

Categories of Contrast Media Negative contrast (AIR OR CO2) Radiolucent Low atomic # material Black on film Positive contrast (all others) Radiopaque High atomic # material White on film

AIR, CO2 BARIUM IODINE RADIOLUCENT - dark on image RADIOPAQUE - white on image BARIUM IODINE RADIOLUCENT IS ALWAYS AIR OR SOME TYPE OF AIR. It helps create air in the image Radiopaque- barium and iodine. Positive makes white on the image. Negative- makes black on the image

Negative Contrast AIR / CO2 LUNGS STOMACH (gas in intestines) Naturally seen in the LUNGS STOMACH (gas in intestines) Air trapped between the liver and the diaphragm on the right side of the body. This is not normal

ABNORMAL AIR IN SMALL BOWEL SIGN OF A BLOCKAGE IN THE SMALL INTESTINE

Solid barium without air

POSTIVE CONTRAST MEDIA IODINE OR BARIUM X-RAY “DYE” INCORRECT TERM COLORLESS OR WHITE

2 BASIC TYPES OF ‘”Positive” CONTRAST MEDIA BARIUM Z# 56 KVP 90 – 120* NON WATER SOLUABLE GI TRACT ONLY INGESTED OR RECTALLY IODINE Z# 53 KVP BELOW 90* USUALLY 70 – 80 KvP WATER SOLUABLE POWDER LIQUID INTRAVENOUS OR GI TRACT OIL BASED DUCTS /ORGANS

Positive Contrast Material INGESTED /INSTILLED (ORALLY OR RECTALLY) BARUIM IODINES GASTROGRAFIN HYPAQUE POWDER INJECTED IV – INTO BLOOD VESSELLS Organs and ducts IODINES IONIC OR NON-IONIC VESSELLS & ORGANS OIL BASED DUCTS /ORGANS ONLY

Methods of Administration of Contrast Material INGESTED / INSTILLED (ORALLY OR RECTALLY) INJECTED IV – INTO BLOOD VESSELLS RETROGRADE AGAINST NORMAL FLOW (Vessels & Organs) INTRATHECAL Spinal canal PARENTERAL (IV, Intrathecal) Injecting into bloodstream (anything other than oral) Retrograde- in bladder or rectum. Parenteral- anything injected or intrathecal

BARIUM BARIUM SULFATE

HISTORY OF BARIUM BaSo 4 LEAD SUBSTRATE – TOXIC BISMUTH SUBNITRATE – TOXIC THORIUM – RADIOACTIVE BARIUM SULFATE - INERT (goes in and comes out the same – not absorbed) NOTE SOME PATIENT MAY SHOW ALLERGY TO SUSPENSION SOL. Lead substrate-was first used and they found it was toxic Bismuth subnitrate- also found it was toxic Barium in inert it comes out the same way it goes out.

Barium Sulfate BaSO+ Esophogram, UGI, Small Bowel,Lower GI or BE 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

Barium Sulfate BaSO+ Because it is not water soluble – it must be mixed in a SUSPENSION with water FLOCCULATION – when barium clumps (separates from the water) Barium residue in the colon can dry and cause an obstruction Drink plenty of fluids after exam Flocculation is when the BA is in the system too long and the BA separates from the suspension it begins to get very hard and can cause a bowel obstruction.

BARIUM MIXED IN A SUSPENSION MUST BE SHAKEN CHECK THE CAP (LID) FIRST !!!!!!! SUSPENSION – sodium citrate, vegetal gums, flavoring and sweeteners to improve palatability

EXTRAVASATION OF CONTRAST INTO PERITONEUM ADVERSE REACTIONS SUSPENSION MAY CAUSE ALLERGY OCG TABLETS (IODINE) ALLERGY AFTER EXAM – MAY SOLIDIFY DIFFICULT TO EVACUATE INCREASE FLUIDS, MILD LAXATIVE EXTRAVASATION OF CONTRAST INTO PERITONEUM

BARIUM CONCENTRATION DIFFERENT FOR EXAMS W/W RATIO (weight/weight) Mixture of barium to water – 100 g suspension “THICK” VS “THIN” BARIUM

BARIUM “THICK & THIN” THICK – DOUBLE CONTRAST THIN – SINGLE CONTRAST

BARIUM ORAL OR RECTAL LABELS ARE DIFFERENT CHECK CAREFULLY BEFORE GIVING TO THE PATIENT BA for rectum has no flavoring so don’t use orally.

Palatability OF BARIUM Chalky taste with barium sulphate/water mixture Contain a flavoring agent, sweetners To disguise the unpleasant taste Thicker or thinner suspensions may be used Many commercial preparations contain carboxymethyl cellulose (Raybar, Barosperse) 1. Which retains fluid and prevents precipitation of the barium suspension in the normal small bowel chalky taste with barium sulphate/water mixture contain a flavoring agent, sweetners To disguise the unpleasant taste thicker or thinner suspensions may be used Many commercial preparations contain carboxymethyl cellulose (Raybar, Barosperse), which retains fluid and prevents precipitation of the barium suspension in the normal small bowel

GASTOINTESTINAL exams BARIUM COATS LINING OF INTESTINE SINGLE CONTRAST - BARIUM ONLY DOUBLE CONTRAST – WITH AIR CARBON DIOXIDE TABLETS – FIZZIES / CRYSTALS SODA ROOM AIR (LOWER GI)

EXTRAVASATION LEAKAGE THROUGH A DUCT OR VESSEL OR ORGAN INTO THE SURROUNDING TISSUE Barium should not be given in cases of suspected perforation

Extravasation Following a Colonoscopy with biopsy

Extravasation of BA in abd

GASTROINTENSTIAL CONTRAST MEDIA PROCEDURES ESOPHOGRAM / OPMS UPPER GI (UGI) SMALL BOWEL (SMBFT) BARIUM ENEMA (BE) GASTRO ENEMA

Drinking Ba for Esophogram

On the RT side there is some narrowing because of peristalsis.

Hiatal Hernia Reflux “heartburn” Hiatal hernia- part of the stomach is moving into the chest cavity. Relux- the food and drinks come back up out of the stomach after eating or driniking.

Supplies for BE

“DOUBLE CONTRAST” studies with Barium Air used with other contrast agents Better to see internal structures BE – room air mixed with Ba UGI – gas “fizzies” used

DOUBLE CONTRAST EXAMS To achieve double contrast examination of the stomach, air or carbon dioxide gas must be introduced Most radiologists use effervescent tablets (sodium bicarbonate , tartaric acid & calcium carbonate) To react with the gastric contents to produce carbon dioxide To achieve double contrast examination of the stomach, air or carbon dioxide gas must be introduced Most radiologists use effervescent tablets (sodium bicarbonate , tartaric acid & calcium carbonate) to react with the gastric contents to produce carbon dioxide

BE SINGLE DOUBLE (AC)

UGI double contrast single contrast

DOUBLE CONTRAST WITH IODINE Iodine mixed with air of a bladder (canine) This is double contrast with iodine of the bladder of a dog

IODINE CONTRAST

Iodine Water Soluble High atomic # 53 Radiopaque Used to radiograph Vessels Arteries Veins Function of internal organs Gastrointestinal system Ducts

IODINATED CONTRAST WATER BASED INJECTED VESSELLS/DUCTS Ionic Non-ionic INGESTED or instilled OPEN WOUNDS OIL BASED INJECTED NEVER VESSELLS ONLY DUCTS NOT INGESTED OPEN WOUNDS

Gastrointestinal studies: Gastrograffin or Hypaque (Iodine) High atomic # Close to iodine Water soluble Similar usage as Barium

Gastrograffin Water soluble iodine-containing contrast media are of value when there is a suspected perforation or leakage of an anastomosis after operation Oral or Rectal use

GASTROGRAFIN POWDERED FORM – MIXED WITH H20 LIQUID IN BOTTLE – MAY BE MIXED USED WHEN PATIENTS ARE ILL, SUSPECTED PERFORATIONS PRE-OPERATIVELY (BITTER TASTE) CAN INCREASE PERISTALSIS (SMB STUDY)

GASTROGRAFIN Bitter taste Better if chilled or mixed with ice Monitor patient closely

Gastrograffin via NG tube

Peptic ulcer Use Gastro Contrast may leak Into the peritoneum Causing peritonitis

Gastric neoplasm w/ perforation EXTRAVASATION OF CONTAST INTO THE PERITONEUM

Gastrografin enema

SINGLE CONTRAST ENEMA BARIUM (110 KVP) GASTROGRAFIN (90 KVP)

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

Never force contrast Patient might aspirate into the lungs! They can aspirate into the lungs if they have had strokes. This is BA into the lungs

INJECTABLE CONTRAST MEDIA INVASIVE PROCEDURES IVP / IVU

Intravenous injections are INVASIVE ALWAYS GET PATIENT’S HISTORY AND CONSENT BEFORE BEGINNING OR GIVING ANY CONTRAST MEDIA

Patient Assessment Check List Information update !!

INJECTED CONTRAST IODINE BASED IONIC NON IONIC

IODINATED Contrast Agents IONIC High Osmolality (Higher risk of complications) (Hypaque) (Conray) NON-IONIC Low Osmolality (Lower risk of complications) (Isovue)

Iodine Contrast Material Non-Ionic Contrast Less patient allergic reactions Ionic Contrast Anion - Cation + More patient allergic reactions Ionic contrast media dissociates into two molecular particles in blood plasma = Causing pt reactions

Newer Contrast Agents Balance Safety and Visualization

IODINE WATER BASED CONTRAST IONIC LESS $$$ $25 per bottle MORE REACTIONS NON IONIC MORE $$$ $200 per bottle LESS REACTIONS

CONTRAST REACTIONS > 10 million diagnostic procedures / year Conventional ionic contrast reactions - 10% 1 in 1000 severe

Allergic to Iodine May or may not react if previous iodine given General Rule: No Iodine Contrast will be given Pre – medication is available May or may not react if previous iodine given

REACTIONS & Treatment USUALLY** WITHIN FIRST 5 MINUTES Nausea & Vomiting & Urticaria Hypotension (bradycardia) Hypertension (tachycardia) Bronchospasm Anaphylactoid Seizures Extravasation

ALWAYS –know the location of drug trays and crash carts

INJECTED IODINE STUDIES GENITOURINARY Contrast injected into the VEIN IVP / IVU CYSTOGRAMS (Retrograde may use a foley catheter) 3. GASTROINTESTINAL 4. ERCP – (CBD)

15 MIN POST CONTRAST INJECTION - IVP CYSTOGRAM

Cholelithiasis GB STONES

Normal ERCP (checks for stones/blockage in bile duct)

GB STONES

Other Injected Contrast Studies

Cerebral Angiogram

Renal Arteriogram

MYELOGRAM (SPINAL CORD) INTRATHECAL INJECTION

Extravasation

“To BE or not to BE” Massive retroperitoneal air pneumomediastinum subcutaneous air secondary to bowel perforation after barium enema Diverticulitis- fecal matter gets stuck in these out pouchings and causes infection.

Extravasation of Contrast into soft tissue of arm

Contrast leaking from bladder

OIL – BASED IODINE CONTRAST

Oil Based Iodine Fatty Acids Insoluble in water Uses White on the radiograph = Radiopaque Uses Bronchography (lungs) Tear ducts Salivary glands Lymphatic system Hysterrosalpingogram Galactography (breast ducts)

To check fertility

LYMPHANGIOGRAM

Galactography - Breast Duct

Oral & IV contrast CT Scan

CT showing Abnormal GB

ORAL & IV CONTRAST (CT/ MRI)