Part V

Question 1

phase encoding main gradient coil [..]

Answer 1

y-axis

Question 2

phase encoding [purpose]

Answer 2

support flipping M to x and y plane, give pulse/extra energy to enhance gradient coil @ left and right side

Question 3

[RF ENRGY?] Phase Encoding

Answer 3

NONE, during PE if RF is introduced, it will not follow Bo

Question 4

frequency encoding main gradient coil [..]

Answer 4

x-axis

Question 5

frequency encoding [purpose]

Answer 5

SPATIAL DOMAIN -initial appearance and readable app. is in TRAPEZOIDAL

Question 6

[component] convert signal to readable signal [process]

Answer 6

Fourier Transformer
Twisting of Form

Question 7

[RF ENERGY?] Frequency Encoding

Answer 7

YES, include FID -energy transmitted from H atoms

Question 8

time to give another sequence from first to second

Answer 8

TR repetition time

Question 9

time b/w application of the RF excitation pulse and the peak of the signal induced in the coil

Answer 9

TE echo time

Question 10

most impo plane in spin echo

Answer 10

TRANSVERSE - where most energy comes from

Question 11

Spin echo with multiple 180 deg corresponding pulses

Answer 11

Fast Spin Echo

Question 12

Fast Spin Echo [purpose]

Answer 12

lengthen exposure H to RF

Question 13

Refocusing Pulse [purpose]

Answer 13

Give 180 degrees pulse to refocus H, make sure precession is same for increase FID

command it to go back - Rabbit and Turtle Principle

Question 14

time you suppress signal of a certain poi

Answer 14

TI - Inversion time

Question 15

[reason] signal starts after 90 degrees in inversion recovery sequence

Answer 15

only used to remove any signal coming from POI

Question 16

[characteristics] T1-W Imaging

Answer 16

short TR and short TE
(less signal - increase intensity b/w x and y)

Question 17

[dark-hypointense T1-W Imaging (E.T.H.I.C)

Answer 17

Edema
Tumor
Hemorrhage (hyperacute, chronic)
Infection/Inflamm
Calcifications

Question 18

[bright-hyperintense] T1-W Imaging (F.F.S.M.P.P)

Answer 18

Fat
Flowing blood (slow)
Subacute Hemorrhage, Melanin
Protein-rich fluid
Paramagnetic substances (Ga, Cu, Manganese)

Question 19

[characteristic] T2-W Imaging

Answer 19

long TR ang long TE

prolong relaxation = higher signal=brighter

Question 20

[dark-hypointense] T2-W Imaging (Ca.Fi.P.-PV)

Answer 20

Calcification
Fibrous Tissue
Paramagnetic Substances (Deoxyhemoglobin, Ferritin, Melanin)
Protein-rich fluid
Flow Void

Question 21

[bright-hyperintense] T2-W Imaging [E.T.I.W.S]

Answer 21

Edema
Tumor
Infection/Inflamm
Subdural Collection
Water

Question 22

STIR

Answer 22

Short TI Inversion Time

Question 23

[purpose] STIR

Answer 23

used to null/suppress signal from fat
180 deg first - sppress signal from fat

Question 24

STIR is good for [..]

Answer 24

bone marrow edema

Question 25

FLAIR

Answer 25

Fluid Attenuated Inversion Recovery

Question 26

IR sequence of FLAIR

Answer 26

long TR and TE

Question 27

FLAIR [purpose]

Answer 27

nulls/suppress signal from CSF or fluid from poi, heavily T2- W

Question 28

FLAIR is good for [..]

Answer 28

detection of hyperintense lesion (adjacent/ near CSF space)

Question 29

FLAIR Structures [Di.N.G.E.M.Fo.T.E.Ch.S]

Answer 29

1. D. affecting brain parenchyma (demyelinating and atherosclerosis) 2. Neonates w/ perinatal Hypoxic Ischemic Encephalopathy 3. Gliomatous cerebri 4. Extra-axial masses 5. Mesial Temporal Sclerosis 6. Focal Cortical Dysplasia 7. Tuberous Sclerosis 8. Embolic Infarcts 9. Chronic Infarcts 10. Subarachnoid hemorrhage

Question 30

DWI

Answer 30

Diffusion Weighted MRI

Question 31

[characteristics] DWI

Answer 31

-takes adv of protons' MOTION to produce signal changes; water=bright -Stationary water molecules unaffected -T2 -compare images where there is movement

Question 32

[evaluate] DWI

Answer 32

STROKE (cerebrovascular accident) OLD and NEW Stroke

Question 33

MRS

Answer 33

Magnetic Resonance Spectroscpy

Question 34

MRS [purpose]

Answer 34

-non-invasive physiologic imaging of the brain -measures levels of various tissue metabolites

Question 35

MRS [techniques]

Answer 35

single -large poi to analyze multivolume- thinner volume/layer

Question 36

look into indiv H atoms and visualize activity w/in poi

Answer 36

MRS

Question 37

MRS [clinical applications classifications]

Answer 37

class a class b class c

Question 38

MRS- Class A [Bra.D. Tu.Mo.R]

Answer 38

1. Brain masses 2. Distinguish neoplastic and non neoplastic masses 3. Tumor Recurrence vs rad'n necrosis 4. Monitoring responses to treatment 5. Research tool

Question 39

MRS-Class B [I.H.E]

Answer 39

1. Ischemia 2. Hypoxia and related b injuries 3. Epilepsy

Question 40

MRS- Class C [Hi.N.A.M.P]

Answer 40

1. HIV d and brain 2. Neurodegenerative disorders 3. Amyotropic lateral sclerosis 4. Multiple Sclerosis 5. Psychiatric Disorders

Question 41

MT MRI

Answer 41

Magnetization Transfer MRI

Question 42

macromole involved in MT MRI

Answer 42

protein, lipid, nucleic acid, carbohydrates

Question 43

alters contrast of tissue on the basis of macromolecular environment

Answer 43

MT MRI

Question 44

MT MRI [Clinical Application]

Answer 44

Tuberculoma and Brain Abscess

Question 45

Qualitative Application

Answer 45

1. MR Angio (except cerebral aneurysm) 2. Post contrast Studies 3. Spine Imaginh

Question 46

Quantitative Application

Answer 46

1. Multiple Sclerosis 2. Multiple System Atrophy 3. Amyotrophic Sclerosis 4. Schizophrenia 5. Alzheimer's D.

Question 47

MRA is used when [..]

Answer 47

if BV is tortous

Question 48

MRA Techniques

Answer 48

TOF (Time of Flight) PC (Phase Contrast) CE (Contrast Enhanced)

Question 49

[MRA technique] no CM is used, detects area where blood flow is present/stenosed

Answer 49

Time of Flight (TOF)

Question 50

[MRA technique] measures moving spins; quantification of blood flow and velocity

Answer 50

Phase Contrast (PC)

Question 51

[MRA technique] used Gd (reduces T1 relaxation time)

Answer 51

Contrast Enhanced (CE)

Question 52

[MRV] used to eval: [..]

Answer 52

thrombosis compression by tumour of the cerebral venous otitis media meningitis sinusitis confusion w/ headache seizures drowsiness