Applied Anatomy/Radiology Flashcards
Where does arch of aorta begin and end?
T4/T5
What accessory muscles of respiration are used when pt leans forward and fixes their arms e.g. onto back of chair?
Serratus anterior
What is a flail segment?
Three or more contiguous ribs are fractured in two or more places
That bit of ribcage moves on its own
Eyebrow sign on CXR
Free gas under diaphragm - pneumoperitoneum
AXR signs of pneumoperitoneum
Inner and outer bowel edges
Outline of falciform ligament
Umbilical ligament outlines
Triangular pockets of gas
What does splenic laceration look like on CT?
High attenuation/dense fluid around spleen - blood
Darkening of patch on spleen - laceration
Dual blood supply to artery
Portal vein
Hepatic artery
Loss of blood flow to kidney looks like?
Kidney looks darker/less white on CT
Def of comminuted fracture
Fracture of more than 2 parts
Cause of avulsion fracture
Detachment of ligament from bone
Signs indicating elbow fracture on XR (radial head)
Anterior sail sign
Posterior fat pad
Colles vs Smith fracture angulation
Colles - dorsal, dinnerfork
Smith - volar
Type of scaphoid fracture causing AVN
Waist fracture
- causes AVN of proximal scaphoid
Where do lateral and medial circumflex arteries supplying neck of femur branch from?
Fermoral and profunda femoris arteries
Twisting ankle can result in what type of fracture?
Malleolar spiral fracture
Features of lower left lobar collapse
Volume loss on the left with elevation of the hemidiaphragm, left hemithorax looks small
Increased density in left retrocardiac region
Loss of clarity medial aspect left hemidiaphragm
Left hilum displaced downwards
Features of upper let lobar collapse
Volume loss on the left, elevation of the left hemidiaphragm
Loss of clarity of the heart shadow
‘veil like opacity’ diffuse opacification of the left hemithorax
Features of upper right lobar collapse
Volume loss on the right
Loss of clarity of the upper right mediastinum
Density in the right upper zone, elevation of the horizontal fissure
Features of middle right lobar collapse
Loss of clarity of the right heart border
Density in the right lower zone,
Right hemidiaphragm preserved
Features of lower right lobar collapse
Volume loss on the right
Loss of clarity of the right hemidiaphragm
Density in the right lower zone, depression of the horizontal fissure
Review areas on CXR
Apices - pancoast, pneumothorax
Behind heart - consolidation, hiatus hernia
Below diaphragm - free gas, lines/tubes, bowel obs
Bones/soft tissue - fractures, subcut emphysema
What is an air bronchogram?
- The bronchus must contain air.
- The surrounding lung must not
Unilateral pleural effusion?
Prob cancer unless proven otherwise
Signs of HF on CXR
A - alveolar oedema (bat wing opacities)
B - Kerley B lines
C - cardiomegaly
D - dilated upper lobe vessels
E - pleural effusion
Normal position of ET tube
normal
tip 5 cm above carina
width 2/3 tracheal diameter
cuff should not expand the trachea
Malposition features of ET tube
tip may extend past the carina
malposition most commonly seen is the tip in the right main bronchus
May have entered the oesophagus
Normal position of NG tube
subdiaphragmatic position in the stomach
- identified on a plain chest radiograph as overlying the gastric bubble
- at least 10 cm beyond the gastro-oesophageal junction.
Where do you insert central lines or PICC lines?
Central lines
- via right and left internal jugular or subclavian veins (CVC)
Peripherally inserted central catheters (PICC)
- via cephalic, basilic or brachial veins
Why is it important that central lines are placed in central vein?
To ensure adequate blood flow for proper dilution of meds
Where does appendix originate from?
Midgut
US findings in appendicits
Aperistaltic, non-compressible, dilated appendix
Round when compressed
Periappendiceal collection of fluid
Target sign/donut appearance
CT findings in appendicitis
Appendiceal dilatation and inflammation
Wall thickening and enhancement
Thickening of caecal apex
Focal wall nonenhancement = necrosis
Gold standard imaging for ureteric stones
CT KUB
Inv for acute diverticulitis
CT with IV contrast to confirm presence of diverticula
- might see perforation on CXR
US findings in acute cholecystitis
Gallbladder wall thickening
Pericholecystic fluid
CT findings in acute cholecystitis
Distension/wall thickening
[finish card]
Why is US used in pancreatitis?
To assess if gallstones is the cause
CT findings in pancreatitis
Diffuse parenchymal enlargement
Indistinct margins = inflammation
Surrounding retroperitoneal fat stranding
Vasc complications (SMV filling defect)
Infected necrosis/abscess formation
Huge volume of gas under diaphragm on CXR?
Perforation
CT findings in perforation
Free fluid
Distribution gas (shows up black)
Defect in wall
Localised inflam change
AXR findings in small bowel obs
Valvulae conniventes are visible (basically small bowel haustra, looks like stack of coins)
Loops of bowel are central
Dilatation >2.5 - 3 cm
Distal pauctiy of gas
CT findings in small bowel os
Dilated small bowel lops >2.5cm from outer wall to outer wall
Normal calibre or collapsed loops distally
Small bowel faeces sign
Sometimes rare causes e.g. gallstone ileus
XR findings in large bowel obs
Peripheral >5cm Haustra
Colonic distension
Collapsed distal colon
Small bowel dilatation if incompetent IC valve
CT findings in large bowel obs
To confirm diag/cause and localise lesion
Non-dependent gas = dying bowel
What is non dependent gas?
Gas sitting underneath fluid in bowel
Means gas is building up in bowel wall as it dies
V bad sign
ABG findings in bowel ischaemia
Metabolic acidosis
High lactate
CT findings in bowel ischaemia
Lack of enhancement of lumen of vessel
Mucosal/serosal enhancement is reduced or incr
Altered wall thickness
Dilated loops of bowel
Pneumatosis intestinalis
Mesenteric oedema/free fluid
CT findings in ruptured AAA
Retroperitoneal haemorrhage adjacent to the aneurysm
- presents w pain, hypotension, pulsatile/expansile abdo mass
Which pts have dilated bile ducts?
Older pts
Pts who have had gallbladder removed
Why does a clot show up hyperattenuated on CT?
Stagnant collection of blood/clot
- full of iron (metal) which shows up dense on CT
Define gliosis in brain
Scarring of brain parenchyma adjacent to lesion/infarct
- hypoattenuated on CT
3 main causes of subdural haemorrhage
Infants - NAI
YAs - RTA
Elderly - falls
Shape differeneces between subdural and extradural haemorrhage
Subdural - semilunar
Extradural - biconvex
When’s the only time you do an emergency MRI?
Spinal emergency e.g. cord compression
Visual pathway for superior and inferior visual fields?
PITS
Parietal - inferior
Temporal - superior
