Pulmonary

Question 1

Mostly used to detect

Answer 1

Pulmonary embolism

Question 2

Indications

Answer 2

Detection of PE, follow up after treatment, quantitative lung function before lung resection

evaluation of lung transplants, CF, cause of pulmonary hypertension, cardiac shunts

Question 3

Contraindications

Answer 3

Pregnant, breast feeding, recent NM

Active wheezing - can cause false positive

Question 4

Pt prep

Answer 4

No prep except focused Hx and recent chest x-ray or chest ct scan
- within 4 hours of scan and acceptable up to 24 hours before scan

Question 5

What blood work is important to include in Hx

Answer 5

Results of D-dimer test

Question 6

What is D-dimer

Answer 6

A test that measures protein fragments in the blood that release when a blood clot dissolves

Can indicate a blood clotting disorder

Question 7

perfusion RP

Answer 7

99mTc MAA

Question 8

Perfusion RP dose

Answer 8

MAA 1 mCi (1-4 mCi)

Question 9

Normal amount of particles for perfusion

Answer 9

200,000-700,000 particles

Question 10

Reduced particles amount

Answer 10

100,000-200,000 particles

Question 11

Who needs reduced particles

Answer 11

Peds, chronic severe pulmonary hypertension, right to left shunts, or pneumonectomy

Question 12

If aerosol is performed before perfusion study, the 2nd study must be _____ times the count rate of the 1st study

Answer 12

2nd study must be 3-4x count rate of the 1st study

Question 13

Injection to imaging time

Answer 13

Immediately

Question 14

Perfusion pt position during imaging

Answer 14

Upright for single head to increase the size of the chest cavity

Supine for dual head

Question 15

Perfusion views

Answer 15

All 8 - planar

Question 16

Perfusion matrix

Answer 16

256x256

Question 17

Planar counts per view

Answer 17

500k - 1 million

Question 18

Pt position for perfusion injection and why

Answer 18

Supine to allow for uniform distribution all the way to the apices (top) - if upright, the particles will settle at the bottom due to gravity

Question 19

Important things to remember when injecting MAA

Answer 19

Gentle agitate vial before injection
Have to cough and take deep breaths before injection
Inject MAA over 3-5 respiratory cycles
MAA adheres to plastic tubing
Do not draw back blood

Question 20

Lung quantification - place ROIs where

Answer 20

Place 3 equal ROIs top, middle, and bottom, of each lung

Determine total activity for each lung in addition to the activity in all 6 regions of interest

Question 21

Normal right to left lung ratio

Answer 21

55:45

Question 22

Pt with chronic obstructive lung disease or signs of reactive airways (wheezing) may use _____ before study

Answer 22

Bronchodilator

Question 23

Perfusion scan shows visualization of kidneys and brain means

Answer 23

Right to left shunt

Need to scan head

Question 24

Aerosol ventilation RP

Answer 24

99mTc DTPA

Or

99mTc Sulfur Colloid

Question 25

Aerosol ventilation RP dose

Answer 25

25 mCi (25-35)

For both DTPA and SC

Question 26

Aerosol ventilation administration to imaging time

Answer 26

Acquisition started on completion of inhalation

Question 27

Of the aerosol dose, only how much is actually delivered to the lungs?

Answer 27

0.5-1 mCi

Question 28

Aerosol ventilation projections and acquisition type

Answer 28

Planar for 8 views

Question 29

Pt position during ventilation

Answer 29

Upright is preferred

But supine if necessary

Question 30

Inhalation process of aerosol

Answer 30

Pt breathes through an oxygen-agitated nebulizer until approximately 100,000 counts into the lungs

Question 31

Gas ventilation RP

Answer 31

133 xenon

Question 32

Gas ventilation RP dose

Answer 32

Xenon 5 mCi

(5-30 mCi)

Question 33

Gas ventilation administration to imaging time

Answer 33

Acquisition started AT first breath

Question 34

Acquisition type and number of views for each phase in gas ventilation

Answer 34

Dynamic

First breath: 1
Equilibrium: 4
Washout: 5-20

Question 35

Time/view for each phase of gas ventilation

Answer 35

First breath: as long as patient can hold their initial breath
Equilibrium: 45 seconds
Washout: 15-60 seconds

Question 36

Pt position for gas ventilation

Answer 36

Erect is preferred

Question 37

Describe what happens during each phase of gas ventilation

Answer 37

First breath: pt takes a breath of xenon and holds it
Equilibrium: have pt rebreathe xenon+O2 and take 4 dynamic images 45 seconds each
Wash out: have pt breath air+O2 while exhaling in xe trap and take serial dynamics for 5 mins