Exam (elaborations)
MRSO IMPLANTS AND DEVICES MODULE 5 QUESTIONS AND ANSWERS
- Course
- Institution
MRSO IMPLANTS AND DEVICES MODULE 5 QUESTIONS AND ANSWERS
[Show more]
Content preview
Name: Score:90 Multiple choice questions
Term 1 of 90
According to ASTM, MR Unsafe is applied to items that:
in writing (faxed reports are acceptable)
Item that poses unacceptable risk in MR environment
tested and labeled for use in your particular MR environment
patient's medical record
Term 2 of 90
When evaluating conditions of an implant regarding spatial gradient, the SYSTEM'S maximum
spatial field gradient is irrelevant. The spatial field gradient amount that should be considered
is
region where the dB/dx is stronger
field strength (due to heating from varying wave length)
The maximum at which the object will be EXPOSED
-torque and force
-vibration
-device interactions
Term 3 of 90
B1+rms expresses
Average of the RF power over time
an item's tendency to align along the direction (axis) of B0 as it is magnetized
at given field strength, items are as magnetically saturated as they will become
homogenous and at maximum
,Term 4 of 90
RF Frequency is determined by
displacement force exerted on an object in a spatial field gradient
-Torque/rotation (B0)
-Translation/displacement (B0)
-RF Frequency/Wavelength (B1)
-verbal and interactive
-performed by Level 2 MR Personnel
Larmor equation
Resonant frequency = static field x gyromagnetic ratio
Term 5 of 90
Heating and SAR:
homogenous and at maximum
are UNRELATED
Average of the RF power over time
simplified
Term 6 of 90
Maximum torque is at
micro-Tesla
isocenter
B0(dB/dx)
simplified
,Term 7 of 90
Slew rate decreases with
the torque force exerted on an item by B0 should be less than the force of gravity
-thicker slices
-larger fov
-reduced receiver bandwidth
-normal mode
-acoustic reduction vendor options
-current in conductive leads
-vibration
-new devices introduced
-most new devices are mr conditional
-labeling changes: design / models / test data / adverse events
Term 8 of 90
International standards for testing were developed by
6 weeks although not necessary unless specifically required by labeling
radiologist
ASTM task group
device manufacturer
Term 9 of 90
Conditions regarding safety and compatibility applies only to
patient's medical record
specifically tested conditions
Item that poses unacceptable risk in MR environment
off-label (device was not tested)
, Term 10 of 90
All testing is designed for
radiologist
increasing frequency of RF
cylindrical bore MR systems only
are NOT all the same
Term 11 of 90
Martensitic
device manufacturer
things designed to hold and edge. Highly ferromagnetic. (surgical stainless)
radiologist
the device manufacturer
Term 12 of 90
Deflection angle is measured by the ASTM using
protractor placed at entrance of the bore near the bore wall. If the deflection angle
measures less than 45 degrees, the magnetically induced force is less than the force of
gravity
patient's medical record
-thicker slices
-larger fov
-reduced receiver bandwidth
-normal mode
-acoustic reduction vendor options
deflection angle is determined then extrapolated to a theoretical "fail point"
-measured angle was likely very small, meaning there should be no concerns regarding
spatial gradients
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller selftest. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $9.00. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
82871 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now