Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Scintigraphy > Bone scan > Flashcards

Bone scan Flashcards

1
Q

What are the three phases of a bone scan and when do they happen?

A

1) Vasculature - Immediate
2) Soft Tissue - 5-10 min
3) Bone - 2-3 hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the activity of 99mTc MDP that is given to smal animals?

A

Small dogs and cats = 5mCi
Meduim dogs = 10-15mCi
Large dogs = 20-25mCi
Giant dogs = 30mCi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the two types of radiopharm used in bone scans?

A

99mTc-HDP (oxidronate)

99mTc - MDP (methylene diphosphonate)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the difference of the blood supply in large animals vs small to the long bones?

A

The bone vessels do NOT cross the physis to supply the epiphysis in dogs and cats but they do in large animals.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Articular cartilage is what type of cartilage?

A

Hyaline cart

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the main unit of bone and what is in the center?

A

A osteon is the main unit and the haversian canal is in the middle which allows blood flow through it and supplies surrounding osteocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is another name for the bone matrix?

A

Osteoid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the main inorganic component of osteoid?

A

Hydoxyapatitie crystal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is uptake of 99mTc MDP directly related to?

A

Osteoblastic activity

Blood supply

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Which is more rapidly cleared from the body…99mTc HDP or 99mTc MDP?

A

99mTc HDP - Therefore the bone phase is 1-2 hours rather than 2-3 hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the bone phase for HDP vs MDP?

A

HDP - 1-2 hours

MDP - 2-3 hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What happens if air is injected into a bottle of MDP? What will you see on a scan?

A

It will produce oxidative degradation which will produce 99mTc04 resulting in thyroid, salivary, gastric, liver or spleen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Perfusion of callcelous bone is how much higher than compact bone?

A

5-13x higher and therefore why you have it light up on bone scans

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

One of the most common artifacts in a bone scan is what?

A

perivascular injection…this will cause a hot spot where the injection site was and cause the lymph node to light up.

This is why they suggest to inject in another leg besides the one that is lame

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What type of collimator is used in bone scans?

A

Low-energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What type of scan is used for the vascular phase?

A

Dynamic - everything else is static

17
Q

Non-skeletal uptake of 99mTc-MDP happens with what?

A

Dystrophic or metastatic mineralization
Rhabdomyolysis
Thyroid if Tc is bad
Hepatic and spleen is Tc is oxidized

18
Q

What would there be a decrease in skeletal uptake or decrease in the target to background ratio?

A
  1. Decreased cardiac output
  2. Soft tissue mass overlying area of interest
  3. Generalized edema
  4. Renal failure
  5. Old age
19
Q

Bone scans tend to over or underestimate the extent of a primary bone tumor?

A

Over estimate (bloom)

20
Q

What neoplastic disease can have a normal bone scan?

A

Multiple myeloma

21
Q

What is the most affect skeletal region from mets?

A

Axial

22
Q

Septic arthritis and osteomyelitis are differentiated from other diseases due to what?

A

The marked increase in the vascular and soft tissue phases

23
Q

Can bone scans tell if an infection site is active or not?

A

NO.

24
Q

Uptake in the area of the medial coronoid has two differentials…

A

Medial coronoid disease

Proximal radial physis

25
Q

When should you do a bone scan after trauma to look for fractures?

A

3-7 days to allow the bone activity to spike

26
Q

What arteries supply the femoral heads?

A

70% from the medial femoral arteries (external iliac)

30% from the lateral circumflex artery (femoral)

27
Q

How long might it take to get a negative on bone scan from a previous fracture?

A

2 years

28
Q

Contaminated stall with 99mTc should not be cleaned until how many half lives have past? How many hours is that?

A

10 half lives or 60 hours

29
Q

What is the dose of 99mTcMDP that is needed for a horse

A

0.2-0.3mCi/kg

At auburn ~ 250mCi per horse

30
Q

What inorganic compound does 99mTc MDP attach to?

A

hydroxyapatite crystal

31
Q

What does the m mean in 99mTc?

A

meta stable — it already gave off a beta particle and is now waiting to give off a gamma ray

32
Q

What is the half-value layer for 99mTc?

A

5cm … so there is 50% attenuation at 5cm of soft tissue

33
Q

What ortho lesions do not cause increase in uptake?

A

OCD or osseous like cyst

34
Q

Acepromazine can be used in horse bone scans if what happens?

A

If you have cold legs because Acepromazine is a peripheral vessel dilator

35
Q

Why does rhabdomyolysis cause increase in ST uptake which 99mTcMDP?

A

They bind with calcium salts in the muscle

36
Q

DDx for photopenic area of bone?

A

Infarct
Avascular necrosis
Tumor necrosis

37
Q

What does lidocaine solution cause in a bone scan?

A

Increase in uptake at the injection site

38
Q

How long does increased uptake secondary to a lidocaine block last?

A

Up to 17 days

Scintigraphy (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions