Contrast media for radiology residents, radiographers and general practitioners.

1. Contrast
media
Mohamed M.A. Zaitoun, MD
Interventional Radiology Consultant, Zagazig University Hospitals, Egypt
FINR-Switzerland
zaitoun82@gmail.com

3. Dedication
To the memory of my late father, Prof Ashraf
Zaitoun Interventional
Radiology Unit,
Zagazig University,
Egypt

4. Knowing as much as possible
about your enemy precedes
successful battle and learning
about the disease process
precedes successful management.

5. -Ideal C.M. should be :
1-Non irritant
2-Non toxic
3-Palatable
4-Little or no side effects
5-Low osmolalty & viscosity
6-High water solubility
7-Heat & chemical stability
8-Cost effective

6. -Classification of C.M. :
Positive
Negative
*Positive (Radio-opaque) C.M.
1-Barium sulfate
2-Iodine preparation
3-Bromide preparation

7. 1-Barium sulfate :
-Ba sulfate is an inert , insoluble organic salt
-Supplied as powdered chalk-like substance
-Administered either orally or rectally
-Exclusively used for GIT
-It never dissolve in water , particles are suspended
in water& may tend to settle down when allowed
to stand for a period of time , so it will be well
stirred before use

8. -Side effects :
hygroscopic effect leading to Ba impaction in
bowel
-Concentration :
Ba swallow 1:1
Ba meal 4:1 or 2:1
Ba follow through 1:1

9. 2-Iodine preparation :
-Advantages >>
a)High contrast
b)Low toxicity
c)Stable binding to benzene ring

10. -Mechanism of development :
1-Tri-iodinated benzene
ring ( C.M. acid
molecule)
1
2
3
4
5
6
COOH
I
R1
I
R2
I
“1950”

11. 1
2
3
4
5
6
COO-
I
NHCOCH3
I
CH3COHN
I
“1955”
2-Removing the H+ from
acid group

12. 1
2
3
4
5
6
COO Na or COO Meg
I
NHCOCH3
I
CH3COHN
I
“1955”
3-Formation of C.M. salt
with sufficient solubility

13. Sodium VS Meglumine
Parameter Sodium Meglumine
Solubility Less Better
Tolerance Less Better
BBB effect Crosses Not
Vascular effects More Less
Viscosity Low High
Diuretic Less Strong
Opacification Better Less
Bronchospasm No Yes

14. -Disadvantage :
Is that it dissolves in the solution into 2 paticles ,
+ve cation ( Sodium or Meglumine ) and –ve
anion ( COO ) so it is called ionic C.M.
-They are 3 ways to reduce C.M. high osmolality
( dissociation ) :

15. 1-Forming ionic dimeric benzene molecule

16. 2-Forming non-ionic monomeric molecule :
By replacing salt group by a compound that
doesn’t dissociate

17. 3-Combination >> non-ionic dimeric molecule

18. 1-Ionic dimeric CM
Hexabrix 320 (sod-meg ioxaglate)
2-Nonionic monomeric CM
Amipaque (metrixamide)
Ultravist 370
Iopamiro 370
Omnipaque 350
3-Nonionic dimeric CM
Isovist 300

19. -Classification :
1-Organic iodine compunds
2-Inorganic iodine compounds
3-Iodized oil

20. I-Organic iodine compunds :
a)Ionic C.M. >> ( High osmolality )
*Ionic monomeric
-Oral cholecystographic agents :
Biloptin
Telepaque
-Urographic/Angiographic agents :
Urographin
Urovision
Urovest angiographin

21. *Ionic dimers :
-I.V. cholangiographic agents
Biligraphin
-Angiographic /Myelography agents
hexabrix

22. b)Non-ionic C.M. >> ( Low osmolality )
1-Monomeric :
*Myelographic
-Amipaque
-Metrizamide
*Uro/Angiographic
-Omnipaque
-Ultravist
2-Dimeric :
-Myelographic >> Irovist
Iotrodan

23. II-Inorganic iodine compunds :
Na iodide 5-7 % >> ascending cystography
III-Iodized oil :
Lipidol used in >>
HSG
Sialograohy
Fistulography
TOF
Lymphangiography
urethrography

24. 3-Boromide preparation :
-Given to patient who are allergic to iodine

25. *Negative ( Radiolucent ) C.M. :
-Air , O2 , Co2
-O2 & Co2 are preferred than air as they are absorbed
easier in blood >> less possibility of embolism
-Uses :
1-Gas myelography
2-Perianal air ( insufflation )
3-Arthrography
4-Double contrast Barium
5-Double contrast cystography

26. C.M. in U/S
-Gas microbubbles < 10 micron in diameter
-Advantages :
1-Too small to be arrested even in capillaries >>
no fear of embolism or infarction
2-Made of inert gas that dissolve rapidly

27. -Types :
1-Hevorisin >> air bubbles coated with galactose and
palmitic acid
2-Echovist >> coated with galactose
3-Echogen
4-Albumex >> coated with albumin
-Action :
-Provides a highly reflective interface that cause
delineation of vessels

28. -Uses :
1-Echocardiography
2-Visualization of lower limb vessels that can’t be
seen by Doppler due to sound attenuation
3-Characterization of hepatic metastases
4-Assessment of hepatic vasculature after
transplantation
5-Assessment of fallopian tubes patenccy at HSG

29. C.M. in C.T.
1-Oral CT CM :
-Used for bowel opacificcation
-High osmolar ( ionic ) iodine C.M.
( Gastrographin )
-Given 12 hrs , 5 hrs before the procedure then on table
2-Transrectal C.M. :
-For colon opacification
-150 ml

30. 3-I.V. C.M. :
-They are used for opacification of vascular tree depending on the
rate of injection & acquisition time
-Brain >> 50 ml
Abdomen >> 100 ml
-In triphasic CT >>
a)Arterial enhancement at 20 seconds
b)Venous enhancement at 60 seconds
c)Delayed at 5-10 min
Level of C.M. decreases due to shift towards tissues ( renal
excretion )

31. C.M. in MRI
Para magnetic agent ( Gadolinium )
Super magnetic agent ( Iron oxide )
1-Paramagnetic agent ( gadolinium ) :
-Action >>
a)Shortening of T1 relaxation time >> increases the signal intensity
b)Shortening of T2 relaxation time >> decreases the signal
intensity
-Best given in T1

32. -Chemistry :
Gd alone is toxic , so it is given bound to DTPA or DOTA
-Dose :
0.2 ml /kg slowly I.V.
-Indications :
1-Detect intracranial tumors
2-Differentiate between tumors & edema
3-Differentiate between disc prolapse & post-operative scar
4-Differentiate between tumor recurrence & post-operative fibrosis

33. -Complications :
1-Headache , nausea & dizziness
2-Seizures
3-Abnormal taste
4-Anaphylaxis
5-Pain & warmth at injection site

34. 2-Supermagnetic agent ( Iron oxide ) :
-Uptake by Kupffer cells in liver >> can
distinguish between normal liver & tumors
-Action >>
Shortening of T2 relaxation time
-Best given in T2
-Oral or I.V.
-GIT contrast agent

35. C.M. adverse reactions
a)Adverse systemic reaction
1-Clinically ( according to severity ) :
Minor , moderate & severe
2-Pathologically
Idiosynecratic non-idiosyncratic
b)Organ toxicity :
1-Kidney
2-Heart
3-Lung
4-CNS
5-Soft tissue

36. I)Adverse systemic reactions :
1-Clinically
i)Minor reactions >>
-Of limited duration & consequences
-Incidence is 10 % of all individuals
-Require no treatment
-e.g. >> nausea , vomiting , sensation of warmth
or mild skin rash

37. ii)Moderate reactions :
-Incidence more in young adults
-Require treatment
-e.g. >> Extensive urticaria , angioneurotic edema , bronchospasm ,
laryngospasm & hypotension
iii)Severe reactions :
-Life threatening
-Require intensive treatment
-Incidence in all age groups ( common in old )
-e.g >> severe bronchospasm , laryngospasm & hypotension

38. 2-Pathologically :
a)Non-Idiosyncratic reactions
-Limited & of minor importance
-Consequence of the physical & chemical
characteristics of C.M.
-e.g. >> hyperosmolarity , chemotoxicity of
iodinated benzoic acid derivatives
Clinically vasodilatation , tachycardia , bradycardia
, hypotension & flushing

39. b)Idiosyncratic or anaphylactic reactions :
-Include the intermediate & severe fatal reactions
-Pathogenesis of reations >>
1-Release of vaso-active substances e.g. histamine &
serotonin
2-Antigen-antibody reaction
3-Disturbance of activation systems , e.g. kinin ,
coagulation & fibrinolysin
4-Psychological reaction

40. -Prophylaxis :
1-Non-idiosyncratic reactions
a)Nausea & vomiting by prolonging the time of injection
b)Arm pain ( due to venous endothelial irritation )
-Selecting a large vein
-Flushing the vessel with saline
-Using a meglumine salt rather than Na salt (more irritant)

41. 2-Idiosyncratic reactions :
a)Screening patients for determined risk factors >>
-Risk factors : a patient with history of allergy is more
likely to develop a severe reaction more than another
without such history
-Risk group includes >> asthma , hay fever & eczema
-A prior sensitivity to urographic C.M. increases the risk
of severe reaction

42. b)I.V. injection of a test dose of C.M.
c)Hydro-cortisone 100 mg orally or parenterally at
least 12 hours prior to injection ( provide
protection for idiosyncratic reaction )
-An open I.V. line is maintained open during C.M.
for further injection of medication

43. c)A resuscitation team at the time of injection to
deal with any life threatening condition
d)Antihistaminics ( hasn’t been accepted as
effective preventive measure )
e)Rapid injection of C.M. is proved not to
precipitate an adverse systemic reaction than a
slow injection

44. -Treatment :
1-Minor reactions >> no traetment
2-Major reactions >>
-Antihistaminics has no role
-Hydrocortisone used in prophylaxis of the high
risk patients

45. 3-Fundamental therapeutic measures >>
a)Epinephrine for hypotension , bronchospasm ,
laryngospasm & angioneurotic edema
-Route of administration :
S.C. 1:1000 epinephrine 0.2-0.3 ml
I.V. 1:10000 epinephrine ( not used in old age or
CV diseases )

46. -Hypotension :
*With tachycardia >> give epinephrine
*With bradycardia (due to vagal stimulation ) >>
give atropine 0.5-2 mg I.V.
-Laryngeal edema :
Isn’t responding to traetment we do tracheostomy
& administer oxygen

47. b)Volume expansion
-For hypovolemic shock due to increased capillary
permeability
-Treated by saline or Ringer’s lactate solution

48. II)Organ toxicity :
1-Nephrotoxicity
-C/P >>
Oliguria or anuria
-Pathology >>
a)Acute tubular necrosis
b)Acute obstruction of tubular lumen by
precipitated solutes or proteins

49. -Incidence >>
a)Acute tubular necrosis occurs in patients with :
1-Low flow rate ( CHF & hypotension )
2-General vascular disease ( arteriosclerosis &
nephrosclerosis )
3-Pre-existing renal failure (diabetic nephropathy
& chronic glomerulonephritis)

50. b)Acute obstruction of tubular lumen by :
1-Abnormal urinary protein ( multiple myeloma )
2-Uric acid ( patient with very high serum uric acid
level ) C.M. has a uricosuric effect )

51. -Treatment >>
By large fluid intake , alkaline diuretic + allopurinol
-Protocol of protection against C.M. nephrotoxicity:
1-I.V. hydration 12 hours prior & during exam
2-Use a moderate amount of C.M.
3-Manitol infusion after C.M. administration
4-In renal failure : hemodialysis or peritoneal dialysis may
be needed due to slow removal of C.M. by kidney

52. 2-Cardio-toxicity :
a)Cardiac arrythmias
b)Ischemia ( increased HR leading to increased O2
demand )
c)Conduction abnormalities
d)Others >> chest pain , loss of consciousness , cardiac
arrest
-Precautions >> in high risk patients
a)Avoid bolus injection ( injection rate at 1 ml/sec or
injection over 10-16 minutes )
b)ECG monitoring during exam

53. 3-Pulmonary toxicity :
-Bronchospasm due to >>
a)Direct pulmonary toxicity
b)Idiosyncratic reaction
4-Neurotoxicity :
-Convulsions
-Cerebral hypoxia

54. 5-Soft tissue toxicity :
-Sloughing of skin and edema of soft tissue due to
extra-vasation of C.M.

55. C.M. in G.I.T.
1-Ba sulphate
-Used as :
Ba swallow , Ba meal , Ba follow through & Ba enema
-Character :
1-High density for GIT
2-Resistance to aggregation of particles
3-Resistance to flocculation

56. 2-Gastrographin
-Uses :
a)If there is suspected perforation ( contrast will
be seen in peritoneal cavity in plain film , then in
the bladder after 2 hours )
b)Post-operative due to possibility of leakage
c)In CT scanning of the abdomen for
opacification of the GIT

57. 3-Air & Co2
-For double contrast study ( Ba meal & enema )
for mucosal pattern
4-Urographin :
Used in sialography

58. C.M. in respiratory system
-Hytrast is used in bronchography
C.M. in myelography & CT myelography
-Omnipaque
-Amipaque
-Myodil ( not used )

59. C.M. in biliary system
-Oral cholecystogram : biloptin , solu-biloptin & telepaque
-T tube cholangiogram : diluted urographin
( as it is very irritant )
C.M. in female genital system
-Urographin 76 %
-Lipidol

60. C.M. in renal system
a)I.V.U.
-Urographin 76 %
-Urovision 58 %
-Non-ionic ( ultravist ) in patients with sensitivity towards
urographin (expensive)
b)Retrograde pyelogram
urographin 30 %
Hypaque 25 %
c)Cystogram & urethrogram
Urographin 30 % or ( 76 % diluted 1:4 )

61. C.M. in lymphangiography
-Lipidol in the dorsum of the foot ( films taken after 24 , 48 & 72
huors )
C.M. in angiography & venography
-Urographin ( high concentration )
-Angiographin
-Hypaque 85 %
C.M. in sinogram
-Urographin 76 %