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Human Loco-motor Systems > Medical Imaging > Flashcards

Flashcards in Medical Imaging Deck (32)
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1
Q

What is a Doppler test?

A

High freq ultrasound to measure the amount of blood flow through your arteries and veins

2
Q

2 types of interactions occur during X-rays, what are they?

A

Penetrate and Scatter

3
Q

How does an Ultrasound work?

A

Putting electric current through a piezoelectric crystal produces sound waves. When the sound waves return, you squeeze the crystal to convert sound to an electric current.

SONAR = Sound Navigation and Ranging

Ultrasonic devices are used to detect objects and measure distances.

4
Q

Faraday cage

A

MRI uses same bandwidth as ABC radio hence needs to be in a copper lined room to block it out (64 Hz)

5
Q

What can’t ultrasound penetrate through?

A

Bone, fat and gas

6
Q

Nuclear medicine uses a scintillation crystal - what is it?

A

Gamma camera

7
Q

What chemicals do we use for different areas?

A

Bone - phosphonate
Kidney - Mag3
Heart - Sestamibi

8
Q

Thecal sac

A

The thecal sac or dural sac is the membranous sheath of dura mater that surrounds the spinal cord and the cauda equina. The thecal sac contains the CSF in which the spinal cord ‘floats’.

9
Q

Where does pain from the lumbar spine get referred to?

A

Buttocks and legs -distributed along sciatic nerve

10
Q

Name 2 methods that are infeffecitive for imaging spinal injuries

A

US - sound doesn’t penetrate bone

NM - doesn’t give info about pathology

11
Q

LUMBAR VERTEBRA

  • Side profile
  • Anterior profile
A

square to rectangular

rectangular with “overhangs”

12
Q

Spondylolisthesis

A

It is the forward displacement of a vertebra, especially the fifth lumbar vertebra, most commonly occurring after a fracture. Backward displacement is referred to as retrolisthesis
-Facet joints fail & lead to excessive forward movement & compression of nerves

13
Q

Desiccation of nucleus pulposus

A

Process of extreme drying leads to proteoglycans of nucleus resembling coconut and no longer spongy.

14
Q

What happens due to desiccation of nucleus?

A

Leads to annular cracks, where defect in the annulus allowing nucleus to squeeze through, causing compression on the nerves.

15
Q

Disc bulge

A

“grand dad’s underpants” loss of elasticity & weakness of annulus fibrosis

16
Q

Herniation

A

Protrusion - Focal extension (neck breadth > depth)

Extrusion – more extreme extension (neck breadth

17
Q

Spondylitis (different to Spondylolisthesis)

A
  • Degenerative arthritis of the spine
  • Disc desiccation – loss of disc height, secondary arthritis
  • Compression of trefoil appearance due to osteophytes growing off vertebral bodies
18
Q

Spinal canal stenosis – What is it & treatment?

A

Laminectomy - a surgical operation to remove the back of one or more vertebrae, usually to give access to the spinal cord or to relieve pressure on nerves.

-Epidural steroid – cortisone anti-inflammatory drug inserted into epidural space (between bone & thecal sac

19
Q

Knee is 2 shallow symmetrical sockets that are highly constrained

A

Knee is 2 shallow symmetrical sockets that are highly constrained

20
Q

Radiographic anatomy : ball and socket (concentric rings x 2)
•rings to maintain stability
–similar to shoulder
What are the 5 layers?
Which layers are most prone to wear and tear?

A
  • bones – layer 1
  • meniscus – layer 2
  • ligaments – layer 3 (most important)
  • capsule – layer 4
  • tendons – layer 5

Layer 1 and 2 are most prone to wear and tear

21
Q

Segond fracture

A

Segond fracture is an avulsion fracture of the knee that involves the lateral aspect of the tibial plateau and associated with ACL tear.

22
Q

Would you use X-ray or CT for patients with plasters around their leg? Why?

A

CT - it is cross sectional where X-ray would make it 3D to 2D

23
Q

Diaphyseal aclasis

A

An inherited autosomal dominant disorder in which multiple osteochondromas are seen throughout the skeleton - sprouting bits of bone coming off all bones of the body

24
Q

Degenerative osteoarthritis

A

Wearing away of articular cartilage - leading to bone spurs

25
Q

How to fix articular surface that has worn out?

A

Knee Arthroplasty - Replacing bone of femoral condyle and tibial plateau with metal that will articulate smoothly. Polyethylene in between the metal (allows for articulation). Lasts 10 to 20 years.

26
Q

What colour are menisci, tendons and lig. in MRI? Water is white on T_

A

Black - anything without water is black

Water is white on T2

27
Q

IN MRI - What colour is cortical bone? Trabecular bone? Cartilage?

A

Cortical - black
Trabecular - white (contains bone marrow that is fatty)
Cartilage is grey

28
Q

ACL and PCL do not heal like other ligs. in the knee, hence how do you treat it?

A

Take a part of the patella or semitendinousus tendon and reconstruct it where the ACL used to be

29
Q

Where does joint effusion occur? How do we look at the joint?

A

Suprapatellar pouch using an arthogram

An arthrogram is a test using X-rays to obtain a series of pictures of a joint after a contrast material (such as a dye, water, air, or a combination of these) has been injected into the joint

30
Q

Role of patella in relation to patellar tendon

A

Protects the tendon as it passe over bone and increases its strength.

31
Q

Patellar tendinopathy

A

Overuse injury affecting your knee. It is the result of your patella tendon being overstressed aka jumper’s knee

32
Q

What happens to patella bone in patellar tendon rupture?

A

The bone goes up into the thigh