Chapter 25 - Arteriography

Question 1

Difference between fixed-mount and portable fluoroscopy units

Answer 1

1) fix mount 10x more resolution 2) fix mount larger field of view 3) fix mount has tableside controls 4) portable can be moved from room to room 5) portable easier to operate 6) portable cheaper

Question 2

ionic contrast key points

Answer 2

Anion = benzene ring with 3 iodine atoms Iodine atom absorb x-ray photos Cation = sodium, methyglucamine or combination double in osmolarity when in blood = 1500-1700 mOsm

Question 3

Plasma osmolality

Answer 3

285 mOsm

Question 4

non-ionic contrast

Answer 4

No dissolution of benzene compound but with same number of iodine atom but less charge Dimeric contrast agent = two benzene rings together to reduce osmolality more Osmolality 320-880 mOsm

Question 5

CO2 angiography key points

Answer 5

1) space runs 3-5 min in between to allow complete dissolution 2) Trendelenburg position 20-30 degrees to slow distal blood flow and increase concentration 3) nitrogen gas is not soluble and must be expelled first

Question 6

Typical injection method, rate and volume of contrast to various vascular regions

Answer 6

TABLE 25.2

Question 7

Pixel shifting define

Answer 7

Digitally fix the shifting to account for the artifact generated by moving patient

Question 8

View tracing define

Answer 8

Opacification, consolidation, stacking images to one also superimposes motion artifacts can pixel shift first each of the images

Question 9

Single-injection multiple-linear field (bolus chase) techniques

Answer 9

Stage = image intensifier starts at feet then travel north to acquire mask Image chases the bolus Stepping technique = finer movements stepping down to chase contrast mask images acquired at the end by machine with same steps

Question 10

Limitations of single-injection multiple linear field arteriography

Answer 10

1) patient movement 2) non-symmetrical disease and flow of contrast down two limbs

Question 11

Rotational arteriography define

Answer 11

1) rotational image capture and incorporate software to print multiple planes 2) present algorithm 3) 3D images 4) rotates from 90 to 213 degrees

Question 12

3D fusion key points

Answer 12

1) pre-operative CT overlay intraop image as roadmap 2) wire presence 3) software might correct in advance

Question 13

Anxiolytic and narcotics to be used for arteriography

Answer 13

1) Midazolam (Versed) 1-2 mg IV 2) Fentanyl 25-50 mcg IV

Question 14

Recommended radiographic filming projection for various branch separations

Answer 14

TABLE 25.3

Question 15

Benefit of CTA/MRA over arteriography

Answer 15

1) diagnosis in question may avoid intervention 2) route of percutaneous access uncertain 3) need juxtaposition body image information in soft tissue/bone

Question 16

Benefit of arteriography over CTA/MRA

Answer 16

1) physiologic testing 2) vasodilator drug 3) blood sampling

Question 17

Allergic reaction to contrast treatment

Answer 17

1) Inhaled adrenergic medication (albuterol) 2) IV epinephrine 3) vasopressor 4) mechanical ventilation 5) atropine 0.5-1.0 mg

Question 18

Conditions that may be associated with severe contrast reaction

Answer 18

1) asthma 2) other allergies 3) anxiety

Question 19

Pre-dosing contrast allergy patients

Answer 19

1) 32 mg methylprednisolone 12hr and 2 hr before contrast 2) use ionic and higher osmolar contrast agents 3) 50 mg prednisone 13, 7 and 1 hr before contrast with diphenhydramine

Question 20

Cardiac toxicity of contrast agents

Answer 20

1) imbalance sodium and calcium 2) contrast binds calcium = arrhythmia 3) bradycardia and hypotension 4) low osmolality agent is better

Question 21

Hematologic toxicity

Answer 21

1) RBC aggregate in contact with contrast 2) anticoagulation considered

Question 22

Incidence of contrast-induced nephropathy as a function of Cr level

Answer 22

normal renal function 1-2% Cr 115-168 = 10% Cr > 177 = 62%

Question 23

Metformin regimen before contrast procedure

Answer 23

1) use low osmolality contrast agent 2) stop metformin 48 hr after procedure 3) stop metformin before procedure if impaired kidney function

Question 24

Lactic acidosis symptoms

Answer 24

1) n/v, somnolence 2) epigastric pain 3) anorexia 4) lethargy 5) diarrhea 6) thirst 7) pH < 7.25 8) lactate > 5 9) anion gap > 15 10) increase lacatate-pyruvate ratio

Question 25

Most common CO2 contrast adverse events

Answer 25

1) mesenteric ischemia secondary to gas trapping 2) neurotoxicity - avoid use above diaphragm