Final exams Flashcards
Which of the following studies may be ordered for uncontrollable hypertension?
MRA abdomen (renals)
A double IR is a T1 blood-suppressed image resulting in black blood appearance
True
Blood flow velocities are greater at the ____ of the vessel:
Center
Contrast enhanced MRAs can be acquired with all of the following EXCEPT:
VENC
______________ occurs after the R wave is detected.
Trigger Delay
Which indicates a contraindication for contrast injection during a renal MRA
- Brest feeding
- renal failure
- GFR below 30
- All of the above
All of the above
Phase contrast techniques produce images in which the signal intensity within the vessel is dependent on which of the following factors
- T1 of tissue
- Velocity of blood flow
- FOV
- matrix
velocity of blood flow
At standard does, gad has the most apparent effect on__relaxation time and is therefore used as an enhancement agent on ___
T1/T1
Which sequence is appropriate for bright blood imaging
- spin echo
- balanced gradient echo
- FLAIR
- STIR
balanced gradient echo
Typical spin echo sequences produce images known as ___in cardiac imaging
black(dark) blood imaging
What is the minimum TR that would be required for a gated cardiac MRI procedure for a patient that has a heart rate of 80 bpm?
750ms
What is the extrinsic parameter that controls the amount of diffusion seen in an image?
B-value
a GE-EPI in perfusion imaging is used for?
for speed and to accentuate the T2* effects with a gradient echo
What imaging technique uses strong multi-directional gradients, provide models of brain connectivity, and is a standard for white matter disorders?
DTI
Due to its sensitivity to venous blood DWI is commonly used in traumatic brain injuries and for high resolution brain venography?
T/F?
False
Motion is the number one hurdle technologists face when scanning pediatric patients
T/F?
True
When scanning a pt fro seizures the coronal image should be angled with the hypocampus
T/F?
True
The Rt and Lt renal arteries lie inferior to the…
Superior mesenteric artery
Inferior mesenteric vein empties into the splenic vein
T/F?
True
What technique uses a short echo time and flow compensation to make flowing blood much brighter than stationary tissue?
TOF
Which plane should be acquired for a MRA runoff study?
Coronal
An advantage of non-contrast MRA is the ability to image slow flow often found in pts with vascular diseases?
T/F?
True
___is controlled by using a fast breath-hold or respiratory triggered acquisitions
Respiratory motion
Typically how many leads are used for gating?
4
The mapping of white matter tracts can be accomplished by using strong multi-directional gradients in a technique called?
DTI
You should always allow a parent to go into the scan room with the pt.
T/F?
False
Peripheral pulse gating can be used for heart imaging?
T/F?
False
What imaging technique is used to eliminate signal from water?
FLAIR
The signal emitted by the voxel of interest in a scan utilizing PRESS is a?
Spin Echo
For a MRA runoff study that contrast is being administered what gauge needle should be used?
20-22
TOF MRA exams use what parameters to suppress signal in stationary tissue?
- TR
- Flip angle
Identify which of the following are a characteristic of any MRA procedure.
- Acquire a setoff flow-sensitive base images
- suppress the signal from stationary background tissue
- generate projection images
- enhance the signal from stationary background tissue
- Acquire a setoff flow-sensitive base images
- suppress the signal from stationary background tissue
- generate projection images
A 2C TOF MRA is ordered on a pt with a suspected occluded carotid artery. To reduce the risk of saturating the signal from blood, which is the best slice orientation for the 2D slice?
Axial
What pulse sequence is used to detect strokes?
DWI
Phase contrast angiography depends on___to generate the base images
- inflow enhancement
- flow voids
- none of the above
- phase effects of flow
Phase effects of flow
Peristalsis can cause artifacts in the pelvis?
T/F?
True
What sequence should be used in perfusion imaging when the transient change in T2* is measured?
GE-EPI perhaps with echo shifting where the TE is longer than the TR
The parameter b factor is measured how?
s/mm^2
A TOF MRA sequence uses a short echo time
T/F?
True
In the pelvis the descending aorta branches into the common iliac arteries?
T/F?
True
Which artifact is caused by the underestimation of maximum blood velocity in the image?
- Maxwell
- turbulent flow
- acceleration
- phase wrap
Phase wrap
What is the best plane to use to visualize the aortic arch?
sagittal
A tear or rip in the vessel is known as:
Dissection
A MRV of the extremities would be appropriate to diagnose:
- AVM
- Necrosis
- Thrombosis
- severity of osteomylitis
Thrombosis
