Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

MRI > Compre reviewer > Flashcards

Compre reviewer Flashcards

1
Q

a continuously changing flow of electrons that alternates its polarity at a periodic rate.

A

AC ( alternating current)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

the total number of independent data samples in the frequency (f) and phase (f) directions.

A

ACQUISITION MATRIX

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

the process of measuring and storing image data.

A

Acquisition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

the period of time required to collect the image data. This time does not include the time necessary to reconstruct the image.

A

ACQUISITION TIME

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

large network of interconnecting blood vessels at the base of the brain that when visualized resembles a circle.

A

CIRCLE OF WILLIS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

the act of maintaining a constant phase relationship between oscillating waves or rotating objects.

A

COHERENCE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

a variation in the nominal Larmor frequency for a particular isotope within the imaging volume. The amount of shift introduced is directly proportional to the strength of the magnetic field, and is specified in parts per million (ppm) of the resonant frequency.

A

CHEMICAL SHIFT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

an artifact introduced into images by interference between adjacent slices of a scan. This artifact can be eliminated by limiting the minimum spacing between slices.

A

CROSSTALK

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

a type of magnet that utilizes coils of wire, typically wound on an iron core, so that as current flows through the coil it becomes magnetized.

A

ELECTROMAGNET

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

an induced spurious electrical current produced by time-varying magnetic fields. Eddy currents can cause artifacts in images and may seriously degrade overall magnet performance.

A

EDDY CURRENT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

a fast spin echo pulse sequence characterized by a series of rapidly applied 180° rephasing pulses and multiple echoes, changing the phase encoding gradient for each echo.

A

FAST SPIN ECHO (FSE)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

This was a fundamental discovery in physics.

A

Rotating Magnetic field

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Who discovered rotating magnetic field

A

Nikola Tesla

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what year tesla discovered rotating magnetic field

A

1882

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

best known for many revolutionary contributions in the field of electricity and magnetism in the late 19th and early 20th centuries.

A

Nikola Tesla

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Recommended limit for constant human exposure

A

2mG

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

The CGS unit for magnetic induction was named gauss in his honour

A

Carl Friedrich Gauss

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

centimeter gram second system of units

A

CGS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

best known for initiating the investigation of Fourier series and their application to problems of heat flow.

A

Jean Baptiste Joseph Fourier

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

s a mathematical procedure to separate out the frequency components of a signal from its amplitudes as a function of time

A

Fourier Transform

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

developed the equation that the angular frequency of precession of the nuclear spins being proportional to the strength of the magnetic field.

A

Sir Joseph Larmor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what year he proposed a quantum spin number for electrons

A

1924

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

proposed a quantum spin number for electrons

A

Wolfgang Ernst Pauli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

proposed the Pauli exclusion principle, for which he received the Nobel Prize for Physics in 1945.

A

Wolfgang Ernst Pauli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What year he proposed the Pauli exclusion principle, for which he received the Nobel Prize for Physics in 1945.

A

1925

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

First to recognize the existence of the neutrino

A

wolgang

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

fermions are particles which obey Fermi-Dirac statistics; they are named after

A

Enrico Fermi.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

states that no two identical fermions may occupy the same quantum state simultaneously.

A

Pauli exclusion principle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

introduced the concept of a spinning electron, with resultant angular momentum and a magnetic dipole moment arising from the spinning electrical charge

A

George Eugene Uhlenbeck

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

succeeded in detecting and measuring single states of rotation of atoms and molecules, and in determining the mechanical and magnetic moments of the nuclei.

A

Isidor Isaac Rabi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Published “A New Method of Measuring Nuclear Magnetic Moment” in 1938, where the first MR signal from LiCl was reported.

A

Isidor Isaac Rabi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

First to demonstrate the phenomenon of paramagnetic relaxation.

A

Cornelius Jacobus Gorter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

discovered electron paramagnetic resonance in 1944.

A

Yevgeny Konstantinovich Zavoisky

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

In September 1937, he and his co-worker Broer, reported unsuccessful attempts to observe nuclear magnetic resonance in pure crystalline materials.

A

Cornelius Jacobus Gorter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

In 1937, He observed the quantum phenomenon dubbed nuclear magnetic resonance (NMR). He recognized that the atomic nuclei show their presence by absorbing or emitting radio waves when exposed to a sufficiently strong magnetic field.

A

Isidor I. Rabi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

In 1946 , They discover magnetic resonance phenomenon.

A

Felix Bloch and Edward Purcell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

In 1946 , They discover magnetic resonance phenomenon.

A

Felix Bloch and Edward Purcell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

developed instruments, which could measure the magnetic resonance in bulk material such as liquids and solids.

A

Felix Bloch and Edward Purcell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Together with his colleagues Torrey and Pound, prepared a resonant cavity to study the absorption of RF energy in paraffin.

A

Edward Mills Purcell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Nuclear induction.
Together with his colleagues, did an experiment measuring an electromotive force resulting form the forced precession of the nuclear magnetization in the applied RF field.

A

Felix Bloch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

The year often regarded to as the birth of MR

A

1952

42
Q

Some book puts the year commonly regarded as the year in which MR was discovered as

A

1946

43
Q

creates a one-dimensional MR image.

A

Herman Carr

44
Q

The strength of a magnetic field is measured in

A

Tesla or Gauss Units

45
Q

The stronger the magnetic field, the stronger the amount of radio signals which can be elicited from the body’s atoms and therefore the _______.

A

higher the quality of MRI images

46
Q

further developed the utilization of gradients in the magnetic field and the mathematically analysis of these signals for a more useful imaging technique.

A

Peter Mansfield

47
Q

First to demonstrate clinical MR images of a human finger using his technique.

A

Peter Mansfield

48
Q

was the first ultra high-speed imaging technique.

A

EPI (echo-planar imaging)

49
Q

Showed how signals can be mathematically analyzed which later gave way to EPI technique in 1977

A

Peter Mansfield

50
Q

development of radionuclide imaging, magnetic resonance imaging (MRI) and, in particular, positron emission tomography (PET).

A

John Mallard, James Hutchinson and the Aberdeen Prototype

51
Q

Originated the “spin-warp” method of spatial localization for MRI

A

John Mallard, James Hutchinson

52
Q

demonstrated with his NMR device, that there are different T1 relaxation times between normal and abnormal tissues of the same type, as well as between different types of normal tissues

A

Raymond Vahan Damadian

53
Q

discovered that hydrogen signal in cancerous tissue is different from that of healthy tissue because tumors contain more water.

A

Raymond Vahan Damadian

54
Q

first MR scanner called

A

Indomitable

55
Q

which manufactured the first commercial MRI scanner in 1980.

A

FONAR Corporation,

56
Q

Fonar went public in

A

1981

57
Q

Raymond Damadian applies for a patent, which describes the concept of NMR being used for above purpose. He illustrates major parts of MRI machine in his patent application i_____________.

A

1972

58
Q

produced the first NMR image. It was of a test tube.

A

Paul Lauterbur

59
Q

described a new imaging technique that he termed Zeugmatography

A

Paul Lauterbur

60
Q

referred to the joining together of a weak gradient magnetic field with the stronger main magnetic field, allowing the spatial localization of 2 tubes of water.

A

Zeugmatography

61
Q

Introduced the use of gradients in the magnetic field.

A

Paul Lauterbur

62
Q

Raymond Damadian receives his patent in ______.

A

1974

63
Q

proposes using phase and frequency encoding and Fourier transform for acquisition of MR images.

A

Richard Ernst 1975

64
Q

introduced 2D NMR using phase and frequency encoding, and the Fourier Transform.

A

Richard Ernst

65
Q

nearly five hours after the start of the first MRI test, the first human scan was made as the first MRI prototype.

A

July 3, 1977

66
Q

demonstrated imaging of the body using Ernst’s technique in 1980. A single image could be acquired in approximately five minutes by this technique

A

Edelstein and coworkers

67
Q

FONAR Corporation receives FDA approval for its first MRI scanner.

A

1984

68
Q

the first commercial MRI system.

A

Toshiba

69
Q

publishes an article in Radiology, which describes diffusion weighted imaging (DWI)

A

Le Bihan in 1986

70
Q

Real time MR imaging of the heart is developed___

A

1987

71
Q

developed the first truly portable MRI technology and made MRI technology available in the office of the clinician

A

1999, MagneVu

72
Q

a computer-based cross- sectional imaging
modality.

A

MRI

73
Q

MRI was originally called

A

nuclear magnetic resonance (NMR).

74
Q

creates images of structure through the interaction of magnetic fields and radio waves with tissue .

A

MRI

75
Q

Small magnet created by the electron spin.

A

MAGNETIC DIPOLE

76
Q

Accumulation of many dipoles.

A

Magnetic Domain

77
Q

artificially produced by charging it in the field of a electromagnet.

A

Permanent Magnet

78
Q

consist of wire wrapped around an iron core.

A

Electromagnet

79
Q

Materials that are unaffected when brought into a magnetic
field

A

Diamagnet

80
Q

Strongly attracted by a magnet.

A

Ferromagnetic

81
Q

(most useful
magnets produced by ferromagnetic material)

A

Alnico – an alloy of aluminum, nickel and cobalt

82
Q

Slightly attracted to a magnet and loosely influenced by an
external magnetic field

A

PARAMAGNETIC

83
Q

CONTRAST AGENTS USED IN MRI

A

Paramagnetic

84
Q

earth’s magnetic field at the equator

A

50 µT

85
Q

earth’s magnetic field at the poles

A

100 µT

86
Q

Typically coils of wire through which a magnetic field is induced

A

RESISTIVE MAGNETS

87
Q

less than 0.3T due to its excessive power requirements.

A

Resistive Magnets

88
Q

The most commonly used magnet.
* Alnico alloy that is used to make permanent magnets.

A

Permanent Magnet

89
Q

only low fixed field-strengths (0.2– 0.3
T) can be achieved

A

Permanent Magnet

90
Q

consist of a coil made of a niobium-titanium (Nb-Ti) alloy

A

SUPERCONDUCTING MAGNETS

91
Q

high magnetic field strengths (0.5–3 T) with low power requirements.

A

SUPERCONDUCTING MAGNETS

92
Q

Special cooling agents are use
to produce low temperature (4 K) is called .

A

liquid cryogens

93
Q

electromagnetic coils are placed in an insulated
chamber called

A

dewar or cryostat

94
Q

process of bringing the superconducting magnets
to the necessary temperature is

A

ramping

95
Q

refers to a magnet’s sudden loss of
superconductivity with subsequent breakdown of the magnetic field

A

quenching

96
Q

contain liquid Nitrogen

A

Outer Chamber of Dewar

97
Q

contains liquid Helium

A

Inner Chamber Of Dewar

98
Q

The precession in MRI is due

A

angular momentum.

99
Q

portion of the magnetic field
extending away from the confines of the
magnet that cannot be used for imaging but
can affect nearby equipment or personnel

A

Fringe field

100
Q

the rate at
which spins wobble when placed in a magnetic field. – DIRECTLY PROPORTIONAL TO THE STRENGHT
OF THE APPLIED MAGNETIC FIELD (B0
)

A

Larmor or precession frequency

101
Q

The component of the net magnetization vector
parallel to the magnetic field is called

A

longitudinal magnetization.

102
Q

The component perpendicular to the magnetic
field is called

A

transverse magnetization

MRI (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions