Nuclear Scintigraphy and contrast studies

Question 1

Compare transudates and exudates

Answer 1

Transudates:

• Pushed from capillaries to surrounded tissues (odema)
• Common with heart failure
• Low protein

Exudates:

• Leakage of fluids from vascular system
• Inflammatory response or infection
• Clear or pus-like

Question 2

What must be considered when using Nuclear Scintigraphy?

Answer 2

• Care with patient after radiation exposure as patient will be ‘radioactive’
• Camera must be temperature controlled (24-27 degrees celcius) and kept covered
• Machine must not be turned off and have power generator
• Must be calibrated remotely
• Use a geiger counter to assess if material that has been in contact with radioactive patients is safe enough to dispose of safely

Question 3

How does Nuclear Scintigraphy create an image?

Answer 3

1. Radioisotopes are administered to the body
2. Molecular activity attracts radiotrancer
3. It is highly sensitive to changes within the body
4. Gives off energy as Gamma rays from the patient
5. Creates 2D image

Question 4

Microaerophiles

Answer 4

Bacteria growth needs oxygen concentration to be less than atmospheric air (2-10%)

Question 5

Facultative anaerobes

Answer 5

Bacteria that can grow with or without oxygen

Question 6

Obligate anaerobes

Answer 6

Bacteria that needs absence of oxygen for growth

Question 7

Obligate aerobes

Answer 7

Bacteria that must have oxygen for growth

Question 8

What is done for a negative contrast study?

Answer 8

Gas administered which has a lower density compared to the surrounding tissue (eg CO2 or nitrous oxide)

Question 9

What is done for double contrast study?

Answer 9

Small amount of positive contrast medium followed by distension via air (more common for the bladder)

Question 10

What is myleography and when is it used?

Answer 10

Introduction of positive contrast medium into the subarachnoid space around the spinal cord. It is used in cases of spinal pain, ataxia, trauma, quadriplegia to show cord swelling or cord compression that is not evident on plain X-rays

Question 11

What are the considerations to be aware of with myelography?

Answer 11

• Must use non-ionic contrast medium
• Use either cisternal or lumbar puncture (clipped and aseptically prepped)
• Patient must be under GA

Question 12

What adverse reactions may be seen on the following contrast studies:

1. Barium
2. Ionic
3. Non-ionic

Answer 12

1. Barium peritonitis & allergic reaction symptoms
2. Renal and cardiac patients, Vomiting & nausea
3. Seizures if enter the brain

Question 13

What is the use/properties of positive contrast mediums?

Answer 13

• Absorb radiation as higher density
• Increases visibility of structures
• Can identify leakages
• Common in CT & MRI

Question 14

What is the use/properties of Barium Sulphate for contrast studies?

Answer 14

• White/chalky material
• Atomic number 56
• Not injected or inhaled
• Well tolerated
• Can be useful to diagnose obstructions via barium impregnated polythylene spheres
• Not used if possible foreign body

Question 15

What are the uses/properties of iodine (water soluble) for contrast studies?

Answer 15

• Iodinated contrast medium excreted via kidneys (IV admin)
• Atomic number 53
• Can be ionic (negatively charged) higher osmotic pressure or Non-ionic (organic) to reduce hypertonicity
• Can be used in GI tract
• Cannot be used during myelography (needs to be non-ionic)