imaging of the lung

Question 1

what is in the lung field

Answer 1

diaphragm and recesses
fissures
hilar region
thoracic cage

Question 2

what is in the mediastinum

Answer 2

heart
great vessels
trachea
soft tissues

Question 3

commonly used medical techniques

Answer 3

radiography - plane and special
CT
MRI 
ultrasonography 
nuclear medicine imaging

Question 4

what is the principle of imaging

Answer 4

body tissues selectively limit the passage of radiation

Question 5

order of tissues from radiolucent to radioopaque

Answer 5

air/gas
fat 
water/fluid 
bone 
metal

Question 6

order of PA components

Answer 6

posterior - x-ray tube
person
anterior - detector

Question 7

what position do you take PA from

Answer 7

erect

Question 8

what position do you take AP from

Answer 8

erect or supine

Question 9

PA view

Answer 9

normal
heart close to film so undistorted
scapular rotated away from the heart
clavicle cross lung field

Question 10

AP view

Answer 10

supine
heart magnified
scapula overlaps
clavicles projected above apex

Question 11

what do you check when you get an x ray

Answer 11

patient details
rotation
inspiration - diaphragm low enough so can see top 9 ribs
AP/PA/lateral/supine
exposure - should be able to see the intravertebral disks behind the cardiac shadow

Question 12

anatomical things to check on an x ray

Answer 12

airways 
bones 
distance of the clavical from the midline is symmetrical
fractures 
circulation 
diaphragm 
effusion - check lung edges are sharp - if not fluid
angle obtuse if atria are enlarged? 
lung fields
gas bubble in stomach 
mediastinal shadow 
aortic knuckle/aorta 
cardiac silhouette 
transverse diameter of heart should exceed 50% of thorax 
any other

Question 13

pneumothorax

Answer 13

no vascular markings 
hyperlucent R lung field
eg clavicle fracture
no lung sounds 
cause tachycardia

Question 14

treatment for pneumothorax

Answer 14

chest drain

Question 15

pleural effusion

Answer 15

fluid in pleural cavity
fluid level in relation to R lobe
right costo-diaphragmatic recess obliterated

Question 16

lung hilar lymphadenopathy

Answer 16

lymph node masses because of sarcoid or lymphoma

Question 17

lung spread from carcinoma of uterine cervix

Answer 17

mass in r middle lobe and hilar nodes

Question 18

pulmonary artery angiogram

Answer 18

special contrast imaging

radio opaque contrast contrast material injected into the pulmonary artery and imaged as pass through arterial tree

Question 19

oesophagus barium swallow

Answer 19

can see the aortic arch impression
Lt main bronchus impression
left arterial impression

Question 20

Tomos (CT)

Answer 20

slice

Question 21

Graphein (CT)

Answer 21

to draw

Question 22

what does a CT do

Answer 22

x ray tube moves in arc around body 
image detectors moves in opposite dirn in same arc 
only axial point in surface 
signal put into a computer 
image reconstructed and displayed 
image viewed from inferior side 
can see the heart chambers

Question 23

choices for CT

Answer 23

standard CT, Ct angiography, contrast, windowing, reconstructions

Question 24

what is a window setting

Answer 24

after scan obtained data is digitally manipulated to reveal different structures in great detail

Question 25

MR imaging

Answer 25

more details and differentiation is seen
uses magnetic field
depends on alignment of protons of H atoms in magnetic field
radio waves excite protons which flip over
they give measurable energy when they flip back when pulsing is removed
more protons (ie more water) emit larger signal
signals processed by a computer and images are formed

Question 26

what planes can you do MRI in

Answer 26

sagittal
coronal
axial

Question 27

T1 weighting

Answer 27

show soft tissues

ventricles of lungs

Question 28

T2 weighting

Answer 28

fluid filled areas more clearly

Question 29

ventricular depolarisation

Answer 29

defect in septum

Question 30

mitral regurgitation

Answer 30

reflux into L atrium

Question 31

how much radiation does an x ray give

Answer 31

equal to 10 days of background radiation

Question 32

what causes an expression in the oesophagus

Answer 32

aortic arch, L main bronchus, l atrium

if heart bigger they block the atrium

Question 33

effect of digital subtraction angiography

Answer 33

make black`

Question 34

what are the surface markings for the heart

Answer 34

3rd CC 1cm from sternal border
6th cc 1cm from sternal border
2nd ICS/CC 2.5cm from sternal border
5th ICS to apex beat and the midclavicular line

Question 35

what is cardiac dullness

Answer 35

when palpate where the heart is you cant hear the resonance that you would be able to hear from the lungs