Cancer imaging

Question 1

Medical imaging

Answer 1

process of creating and interpreting images of body morphology and fx for the explicit purposes of pateint examination and intervention

Question 2

types medical imaging

Answer 2

1. structural/ morphological
2. Funcitonal
3. Molecular imaging

Question 3

Structural imaging

Answer 3

aka morphological imaging
this is 99% of imaging done in vet med
- look for changes in size, shape, opacity
- look to see if tissue normal or if it has changed
- best for diagnosing dx that produces morphological changes (developmental abnormalities, neoplasia, infection, trauma)
- also used to observe functional disturbances (joint laxity or stiffness, difficulty swallowing, inability to urinate)

Question 4

Structural imaging is not helpful when disease

Answer 4

1. does not produce morphologic change (might still be worth imagine to rule out other dxs like neoplasm that do though)
2. does not produce changes at a time that is clinically relevant (early diagnosis = key so if see it in later stage this isn’t helpful to improving prognosis)
3. does not produce morphologic changes that are specific for a case (organs can often have same response regardless of insult so for example increased liver can be caused by MANY things so we know its enlarged but that doesn’t tell us what specifically is causing it)

Question 5

Functional imaging

Answer 5

• provides image that display info about physiologic activities or organ regardless of morphologic changes
• best for answering how well is an organ fxing (ex renal excretion, neuronal activity, lung ventilation and perfusion)

Question 6

how does functional imaging work

Answer 6

physiologic activities measured directly or indirectly by detecting secondary changes in metabolic activity, hemodynamic responses, and chemical composition
- ex. look at neuronal activity not by looking at nerve activity but by looking at blood flow to brain which we know is associated

Question 7

renal syntigraphy

Answer 7

get radioactive isotope that binds to radiopharmaceutical that goes to kidney and can quantify how fast kidney excretes isotope from body; use this to determine how much fx we are getting from 2 different kidneys; tells us if we can take a kidney out if mass on it if other one fxing enough to avoid renal failure ect.

Question 8

how did they image cat brain for blood flow related to blindness / deafness post sx

Answer 8

functional imagine

Question 9

image non-random moving water using diffusion tensor imaging

Answer 9

functional image

Question 10

molecular imaging

Answer 10

• production of images that depict biological processes, especially molecular pathways that take place at cellular and sub cellular level like angiogenesis and apoptosis or the expression and activity of specific molecules like proteases and protein kinases
• structural and functional imaging often show the end results of these molecular alterations

Question 11

how does molecular imaging work

Answer 11

• uses endogenous molecules or exogenous agents to visualize, characterize, and measure biological processes

Question 12

pet scans

Answer 12

functional imaging

Question 13

molecular imaging benefits

Answer 13

• early detection of dx (often before gross morphologic or functional changes)
• differentiating between benign and malignant neoplasms
• predicting tumor response to specific chemotherapies
• monitoring cell growth and death as a means to follow treatment response
• more specific diagnoses
• better delineation of dx extent
• • these are all potentials right now**

Question 14

limitations of molecular imaging

Answer 14

lack of specific targeting agents that are effective; these are becoming more popular and will become imaging of the future

Question 15

hybrid imaging

Answer 15

combine images of two different imaging modalities (ex pet scan = functional combine with MRI= structural)

Question 16

imaging technology used for vet cancer pateints

Answer 16

• radiography
• U/S
• Scintigraphy
• MRI
• CT
• PET

Question 17

goals of cancer imaging

Answer 17

1. monitor treatment response or dx progression
2. determine extent of dx (figure out boundaries of mass so can spare as much healthy tissue as possible)
3. Establish prognosis (is there metastasis?)
4. Make a diagnosis (is problem traumatic, inflammatory, neoplastic ect.)
5. Guide intervention (catheter/ needle to tumor)

Question 18

screening test

Answer 18

early detection: test performed in healthy patient with no sign of dx to look for dx in case it is there (ex hip or elbow dysplasia); mammography in humans

Question 19

Diagnostic test

Answer 19

clinically affected: test preferomed on affect individual

Question 20

extend of dx

Answer 20

1. primary cancer
2. staging
3. secondary effects

extend is important bc need to avoid as much healthy tissue as possible when making treatment plan to maintain best QOL; looks to see if there is distant spread tumors

Question 21

metastasis

Answer 21

invasion
survive circulation
evade immune system
arrest in target tissue (size dependent trapping, specific adhesion molecules)
adhesion and early survival at distant sites
modulation of novel environment
angiogenesis

Question 22

ossifying pulmonary metaplasia

Answer 22

VERY opaque for v small noodles (less than 5mm); these can’t be cancer be soft tissue bc mineral opacity so they are either end on blood vessel or they are mineral opacity (which s going to be due to calcification due to degenerative change)

Question 23

Secondary effects

Answer 23

• obstruction
• functional tummors
• paraneoplastic tumors

Question 24

functional tumors

Answer 24

producing things, can lead to further issues in the body ex. tumor secreting ACTH won’t respond to negative feed back loop so will just overproduce ACTH

Question 25

paraneoplastic syndrom

Answer 25

neoplasm associated alteration in body structure or function that occurs distant to the tumor (tumors can have different chemical affects on body and effect it in a lot of different ways; animals may come in with signs of dx but that dx may be caused for cancer so need to know which dxs can have paraneoplastic syndromes so know what to look for)

ex. hypertrophic osteopathy