Extras

Question 1

Define an X-ray.

Answer 1

An electromagnetic packet of energy (photons) with extremely short wave-length between 0.1 and 10 nanometers.

Question 2

What does the X-ray tube contain?

Answer 2

vacuum, anode, cathode, tungsten target, rotor, oil

Question 3

What are the three types of interactions between X-rays and matter?

Answer 3

1. Scatter
2. Transmission (e.g air)
3. Absorption (e.g tooth)

Question 4

Define attenuation.

Answer 4

Process by which radiation loses power as it travels through matter, increases with density and thickness and increases with atomic number.

Question 5

Relate colour of tissue with attenuation factor.

Answer 5

Whiter tissue = higher attenuation factor.

Question 6

What is a digital radiography?

Answer 6

Digital acquisition of images onto a network of images.

Question 7

What is ultrasound?

Answer 7

Transmit high frequency sound pulses.

Question 8

Describe how ultrasound works.

Answer 8

Sound waves travel into body and hit a boundary between tissues, some waves reflect back to the probe while some travel further to another boundary. Reflected waves are picked up by the probe and relayed to machine which calculates distances using speed of sound in tissue and time of echo’s return to form 2D image.

Question 9

What are the advantages of using ultrasound?

Answer 9

Cheap, portable, no radiation, great for soft tissue.

Question 10

What are barium studies?

Answer 10

A radio-opaque contrast agent is used to outline GI tract. The high atomic number of barium absorbs more X-ray photons than surrounding tissues.

Question 11

What re complications of barium studies?

Answer 11

Bowel disturbances and colonic perforation.

Question 12

Describe CT.

Answer 12

Rotating X-ray tube with multipole beams and a single six of rotation.
often used with iodinates contrast.

Question 13

What is a disadvantage of using CT?

Answer 13

Ionising radiation which can lead to disruption of chemical bonds within living tissue.

Question 14

What measurement is used to describe the absorption of radiation by the human body?

Answer 14

Sievert

Question 15

Describe transformation of cells from ionising radiation.

Answer 15

Leads to altered cell metabolism and function and to cancer development (i.e worse than cell death).

Question 16

How can healthcare professionals minimise exposure to ionising radiation?

Answer 16

Use shield, minimise time exposed, distance.

Question 17

Discuss distance in relation to ionising radiation.

Answer 17

As distance from source doubles, exposure rate decrease by a factor of four.

Question 18

What are the main functions of the lymphatic system?

Answer 18

• tissue drainage
• return of plasma proteins
• absorbed fat transport in gut
• tissue fluid has osmotic pressure
• immunity
• drains escaped cell-free plasma from the extracellular spaces back to the venous system.

Question 19

Discuss the route of the lymphatic system.

Answer 19

One-way from periphery back to centre (due to valves).

Question 20

What is the lymphatic vessels permeable to?

Answer 20

Fluid, lymphocytes, fats (in small intestine) and small proteins only.

Question 21

Where in the body is there no lymphatic drainage?

Answer 21

Epidermis, cartilage, bone, CNS.

Question 22

What controls flow of lymph?

Answer 22

Muscle contraction, valves, pressure changes and gravity

Question 23

What causes tissue drainage in lymphatic system?

Answer 23

Increased hydrostatic pressure forcing plasma proteins out of blood of tissues.

Question 24

What is the function of lymph nodes?

Answer 24

• Acquired immunity

- Reabsorption of lymph (about 8L/day)

Question 25

What is the function of the germinal centres (secondary lymphoid follicles) in lymph nodes?

Answer 25

Maturation, isolation, localisation and activity sites of B and T cells.

Question 26

Where are deep lymph nodes found?

Answer 26

Accumulate at base of limb and within trunk.

Question 27

What causes enlargement of superficial lymph nodes?

Answer 27

Infection (e.g TB and glandular fever), inflammatory hyperplasia and tumour growth (primary tumour = Hodgkin’s lymphoma and secondary as a result of metastasis)

Question 28

What are the drainage routes of lymph?

Answer 28

• Initial drainage = symmetrical from limbs, head, neck and trunk.
• Deep lymphatic drainage follows routes of arterial blood supply
• Ultimately all congregate into 2 large ducts

Question 29

what are the two main lymphatic ducts?

Answer 29

1. Thoracic duct

2. Right lymphatic duct

Question 30

How does a global health perspective enhance patient care?

Answer 30

Goes back to root cause of poor health and disparities e.g social, political, cultural etc.

Question 31

What are the benefits of global health?

Answer 31

• achieves equity in health

- population-based prevention and individual care

Question 32

What has happened to non-communicable diseases in recent years?

Answer 32

Non-commincable diseases (cardiovascular, cancer, chronic diseases and diabetes) have increased

Question 33

Compare health and illness in relation to social gradient.

Answer 33

The lower the socio-economic position, the worse the health.

Question 34

What are the social determinants of health?

Answer 34

• income related to life expectancy
• socioeconomic class and environment
• unsafe water and sanitation
• malnutrition

Question 35

What are disease related to and give examples.

Answer 35

1. Waterborne (e.g cholera, typhoid and dysentery)
2. Water-washed (e.g scabies. lice, tick-borne)
3. Water-based (e.g schistosomiasis and other helminth infections)
4. Water-related (e.g dengue, yellow fever, malaria)

Question 36

What are the three main types of diarrhoea disease?

Answer 36

Bloody, watery, epidemic

Question 37

What interventions can improve global health?

Answer 37

• improved water supply
• water quality interventions
• personal hygiene
• sanitation

Question 38

Name an example of a global health burden.

Answer 38

Access to surgery

Question 39

Name a global health issue.

Answer 39

Maternal mortality.