Midterm Flashcards
What is one extra feature of IR pulse sequence?
TI
What is the TI range for suppressing fat?
80 - 175 (depending on the anatomy)
- 2D VS. 3D :
2D is a slice
3D is a slab (MRA head because arteries are curvy and thinner)
What protocol is used for carotids ?
2D or 3D
Sat pulse for arteries —-
superior
What comes off subclavian arteries?
Vertebral arteries
Internal VS. External carotid arteries:
Internal - supplies blood to the brain; lateral (on coronal view)
External - supplies blood to the face; medial (on coronal view)
What comes off carotid siphon?
Ophthalmic artery
What pulse sequence is used for the venous system?
2D (coronal and axial)
Condition where in the connection between veins and arteries are dilated?
AVM (Arterial Venous Malformation)
What sequence is used for AVM?
Tricks (contrast enhanced)
Sat pulse for veins —-
inferior
What sequence allows you to see the direction of flow?
Phase contrast
What pathology is T2 flair good for?
MS
Diffusion is good for what pathologies?
Stroke, infection, dermoid cyst
What does active/acute stroke look like on diffusion?
Bright (old stroke will be dark; REALLY old stroke will be black because tissue is dead and replaced with CSF)
What sequence confirms if something is a stroke or T2* artifact?
ADC
What does acute stroke look like on ADC?
Dark (old stroke will be bright)
What pathology is GRE good for?
Bleed (also concussion, mv accident, TIA, cavernous malformation)
Multiple dark spots on a GRE is what kind of pathology?
Microbleed
What kind of bleed is on the side of the head and displaces brain tissue?
Subdural hemorrhage (bright on T1)
What is good sequence for the brain post contrast?
T1
What sequence is used post contrast for other parts of the body?
T1 fat sat
What sequence shows lesion as if double dose contrast was given?
MTSE (suppresses background)
What exam will you run for glioblastoma and astrocytoma?
Perfusion (for surgical and treatment prep)
What exam will you run for mets in lung (and primary is in brain)?
Routine brain w/ and w/o contrast
What exam will you run for facial numbness?
High IAC (CN V aka trigeminal nerve)
What exam will you run for h/o meningioma?
Routine brain w/ 1/2 dose contrast
What exam will you run for someone with abnormal blood work (prolactin)?
Pituitary
What exam will you run for optic neuritis?
MS (T2 flair)
What exam will you run for someone who has numbing and tingling on one side of their body?
MS
What exam will you run for someone who has olfactory nerve issue?
Coronal sinus (FSE fat sat)
What scan will substitute if fat sat fails?
STIR
What do you do for metal artifact post contrast?
Turn off the fat sat
How can you reduce metal artifact in terms of adjusting the protocol?
Increase the bandwidth
Best planes for IAC?
Axial and coronal
Best planes for pituitary?
Sagittal and coronal
Best planes for orbits?
Axial and coronal
What is used to calculate GFR?
Creatinine
What is the name of the pathology wherein ventricles are dilated due to excessive CSF?
Hydrocephalus
What pathology can hydrocephalus cause on the spine?
Syrinx
Syrinx is the dilation of what anatomy?
Central canal
What is a good view and sequence to diagnose syrinx?
Sagittal T2
What is chiari malformation?
Herniation of cerebellar tonsils into the neck (cranio-cervical junction). It also leads to syrinx.
When is it not safe to scan a pregnant lady?
During the 1st trimester
What instructions will you give a breast feeding lady who needs contrast?
Pump and dump (48hrs)
What is the main concern for a pregnant technologist?
RF
What is the main concern for the developing fetus exposed to RF?
SAR
What does SAR stand for?
Specific Absorption Rate
What is the SAR limit for normal mode?
2w/kg
Rise in core body temperature should not exceed ________.
(1 degree Celsius)
Which government agency regulates these policies?
FDA
What causes peripheral nerve stimulation?
Gradient magnetic factor
What causes missile trajectory?
Translation traction
What is explosive boil off of helium called?
Quench
What are the risks of a quench?
Frostbite, asphyxiation, ruptured eardrum
Why do patients need to uncross their arms during scan?
To avoid contact burn
What is happening when patients feel a slight electrocution?
Peripheral nerve stimulation
How many salivary glands do we have?
3 pairs (parotid, submandibular, sublingual)
Why do we need to include C-spine on a T-spine localizer?
To be able to count from C2
What artifact commonly shows up around the spine area?
Flow artifact (looks dark)
What sequence is used for MS in spine?
IR
What sequence is used for fracture in the spine?
IR
What procedure is done on spinal fracture?
Kyphoplasty
How can you differentiate C,T and L spine?
C-spine - has bifid spinous process (C3-C6) ; Vertebral prominens, single spinous process
(C7) ; has transverse/vertebral foramen (passage of vertebra arteries)
T-spine - has facets joints as attachment for the ribs ; cord ends around T12 - L2 (conus
medullaris)
L-spine - sits next to psoas muscles; contains cauda equina part of the cord
What artifact makes bleed on GRE look dark?
Susceptibility
What pulse sequence causes chemical shift?
In/out phase sequence
How do can you resolve aliasing?
Increase FOV, use NPW
What artifact does a flickering light bulb cause?
Zipper artifact
What causes corduroy artifact?
Two metals rubbing together
What artifact is produced if a wrong coil is used for a certain body part?
Annefact artifact
What sequence will you run for hydrocephalus?
Midline SPGR (thinner slices, covers the whole head)
What sequence will you run for MS brain?
Sagittal T2 flair
When you’re doing FLAIR you’re trying to suppress
Fluid - Fluid Attenuated Inversion Recovery
When you’re trying to suppress Fat -
80-175 TR
2D TOF -
Slice
3D TOF -
Slab - smaller survey use 3D
For Carotids you can use:
3D and 2D
Sat Pulse direction on arteries of Brain -
Superior
Carotids - Internal and external carotids
external goes to face, internal goes into the brain
Internal carotid curves =
carotid siphon
external carotids -
medial
internal carotids
lateral
Name of artery that connects anterior and posterior circulation
posterior communicating artery
off of basilar another branch -
anterior inferior cerebellar artery
branches off of vertebral -
PICA
Venous Brain -
Superior Sagittal sinus, to straight sinus, transverse sinus goes off to the side, where the connection is confluence of sinus, curving down Sigmoid sinus, down to neck with internal jugular vein, to superior vena cava
Venous Brain -
Superior Sagittal sinus, to straight sinus, transverse sinus goes off to the side, where the connection is confluence of sinus, curving down Sigmoid sinus, down to neck with internal jugular vein, to superior vena cava
what pulse sequence do you scan for venous Brain -
2D coronal and axial
AVM -
(malformation) TRICKS (contrast enhancement) sat pulse INFERIOR
MRA - to see direction of the flow =
Phase Contrast
Pulse Sequences:
T2 FLAIR -
good for MS
Pulse Sequences:
Stroke or infection =
Diffusion
Diffusion is good for -
infection, stroke, dermoid cyst
Acute stroke looks ______ on diffusion
Bright
Old stroke looks ______ on diffusion
Dark or black
ADC - acute stroke is _____
old stroke is _____
Dark
Bright
Gradient Echo GRE - good for ______.
Bleeds
Dark dots on GRE is ______.
micro bleed - subdural bleed is on the outside bleeding in (pushing in on the brain)
Scan GRE for patients with ____________________.
concussion, car accident, cavernous malformation
Once you give someone an injection for brain - good scan is __.
T1
If you’re doing a scan Post gad - use ________.
T1 with Fat Sat
Someone comes in with glioblastoma (cancerous tumor) - important sequence scan _________.
Perfusion (for surgical planning)
Someone with a history of metastatic disease scan ________.
routine brain w w/o contrast
Someone with facial numbness - scan
High IAC for Trigeminal nerve
Someone with history of meningioma (benign tumor of meninges(surrounds brain)) - scan
routine brain and half a dose of contrast
Someone comes in with abnormal blood work - scan
pituitary (prolactin levels)
Someone comes in with optic neuritis - scan
MS T2 FLAIR
Someone has numbing or tingling on one side of the body - scan
MS
Someone has an Olfactory nerve issue - scan
Coronal Sinus —– (if you can’t get Fat Sat to work scan STIR))
Someone has metal you’re giving them contrast for cervical spine -
turn off Fat Sat - or increase Bandwidth
Best plane to see IACs on -
Axial and Coronal
ituitary - best planes
Sagittal and Coronal
Orbits - best planes
axial and coronal
What do you use to calculate GFR -
Creatinine
Looking at CSF moving in the brain - what pulse sequence =
phase contrast with venc
Phase contrast to look at ___.
CSF
Too much CSF in Brain:
hydrocephalus - could lead to syrinx (dilation of central canal)
Good view of pulse sequence to diagnose syrinx:
Sagittal T2
Chiari - could have:
syrinx, CSF everywhere
If RF is on - the patient or baby concern is:
heating
SAR stands for:
Specific absorption rate
GE machine normal mode SAR limit -
2 is normal —- 4 is for research
core temperature is
1 degree Celsius - regulated by FDA
When you talk about RF - peripheral nerve stimulation is
gradient magnetic factor
Magnetic force:
translational attraction
Torque
aneurism clips
Quench:
explosive - frost bite, ruptured eardrums, asphyxiation
When you’re positioning patients you uncross hands - because of
contact burns
When a patient feels like they’re being electrocuted:
peripheral nerve stimulation
What artifact do you see on a spine -
pulsing artifact CSF - flow artifact is CSF - syrinx is in spiel cord not CSF
f you’re looking for spinal plaque -
Inversion Recovery —- IR
If you’re looking for fracture on spine - best sequence
IR Inversion Recovery
Procedure on spine when they put cement in:
kyphoplasty
T1 spine - dark is _________, fracture not as dark
kyphoplasty
How would you now between cervical, thoracic, or lumbar spine?
Cervical - has transverse foramen (vertebral arteries) other two don’t have
Thoracic - facets and ribs, Spinal cord ends around conus medullaris
Lumbar - has cauda equina, psoas muscle
On a GRE a dark hemorrhage is caused by:
susceptibility artifact
Chemical shift artifact cause by:
In and out of phase
Scanning pituitary (Small FOV) and nose/back of head show up:
wrapping or aliasing
2 ways you can solve phase wrap:
swap phase and freq, or larger FOV, turn on no phase wrap
Light bulb goes out in the room, filament:
zipper artifact
Corduroy artifact caused by:
RF leak, or two rubbing metals
When you chose a wrong coil for wrong area on spine:
Annefact - looks like bright line
Someone has hydrocephalus - scan
midline SPGR (anything in the middle of the head when you want a thin slice)
Someone has MS - scan:
Sagittal T2 FLAIR
Optic neuritis scan:
MS Brain = Sag T2 FLAIR
Pituitary Tumors are the only tumor that appears ____.
Dark
Best views of Pituitary:
Coronal and Sagital
Orbits views
Axial and Coronal
Sinuses are the best way to find ________.
contrast
For Stroke - scan:
routine brain and Diffusion and gradient echo
Dermoid cyst is proven by scanning:
Diffusion DWI
Perfusion is for detecting:
tumors for surgery
Diffusion - New strokes _____ old strokes _____.
Bright, Dark
Brain MRA - have to do _______.
3D TOF
Anytime you’re looking for a bleed/stroke - use
gradient echo pulse sequence — GRE
lateral fissure angle to for:
seizure brain
cavernoma
(little berries blood clusters in the brain)
Diffusion 4 - Tensor is
20-60
Main reason for ADC
eliminate T2 Shine through
Pituitary and IAC use
Half dose and Dynamic injection
Pituitary Dx -
Growth Hormone or abnormal bloodwork
*don’t do IR_____ GAD - or it will suppress the legion - do it ___ gad
POST – PRE
ANYTIME you have phase wrap -
swap phase and frequency (it becomes a to p A-P)
MRI Neck - Sagital Sat Pulse -
Anterior Inferior
MS patient - use
STIR IR
to see BLEEDS - use
GRE
MRA neck sat pulse =
Superior
To visualize MS plaque - use
STIR
Brachial nerve passes through ________ muscle
scalene
Subclavian Steal - because of severe
stenosis or occlusion
stenosis - start seeing collections of __________.
collaterals
2D TOF shows _______ vessels
3D is good for smaller vessels (brain)
straight
MRA Above Heart _______ Sat Pulse
Below Heart ________
Superior
Inferior
MRV Above Heart ______ Sat Pulse
Below Heart _______
Inferior
Superior
Pathway of blood through heart:
Superior vena cava, Right atrium to right ventricle to lungs (pulmonary artery de-oxygenated blood), pulmonary artery, left atrium, left ventricle to aortic arch
Phase Contrast PC - done on
subclavian and carotids - shows you the direction of the flow (artery vs veins)
When we give contrastive scar tissue will _______.
light up
STIR and T1 fat sat- makes fat _____.
Dark
lumbar localizer to sacrum -
350 or 400
In TOF sequence flowing blood - doesn’t become saturated by RF pulse because it’s _______.
moving
Motion Artifact - always shows in the ___________.
background
Soft tissue neck
scan after post contrast -
T1 fat sat —— (if there’s metal take fat sat away)
do not use _____ post gad - it will suppress the lesion
STIR
use STIR for___ - bright lesions
MS
Anterior and Middle Scalene muscles =
brachial plexus nerve
___ lymph nods in the neck
300
best way to suppress soft tissue neck -
Shim
SNR increases if you increase ___.
FOV
f slice thickness increases SNR __________.
Increases
If looking for dissection -
Black Blood (pulse ox) or Spin-Echo
If you decrease NEX - SNR __________.
decreases
If you want to see Vertebral arteries -_________ sat pulse
Superior
use if you’re trying to get subclavian
Tricks
Phase Contrast sequence -
shows direction of the flow
vertebral are off the
subclavian
internal carotids go to _____.
brain
decrease bandwidth - SNR __________.
increases
if you increase FOV it will not increase __________.
scan time
f you increase matrix it will increase _________.
scan time
