MR
IMAGING OF BRAIN
Muhammad Bin Zulfiqar
PGR II SIMS/SHL
New Radiology Department
Basics of MR
• MR sequences
• MR signal characteristic
MRI----conventional sequences
• SE sequence ( spin echo )
– T1-weighted,T1-WI
TR: 200-800ms TE:15-30ms
– T2-weighted,T2-WI...
MR signal characteristics
• SE sequences :
– T1-WI: highest signal on fat tissue ,better for showing
anatomical structures...
MR signal characteristics

T2WI

T1WI
MR signal characteristics

Fat supression

Liquid supression
THREE DIMENSIONAL
BRAIN ANATOMY
5

3

Post Contrast sagittal T1 Weighted
M.R.I.

2

Section at the level of Foramen
Magnum

1

Answers
4

1. Cisterna Magn...
Post Contrast sagittal T1 Wtd
M.R.I.
Section at the level of medulla
6

Answers
7

Fig. 1.2 Post Contrast Axial MR Image o...
14
13
12
Post Contrast sagittal T1 Wtd
M.R.I.

11
17

10
16

15

Section at the level of Pons

Answers

9

13. Internal Ca...
20

22

19
18
21

Post Contrast sagittal T1 Wtd
M.R.I.
Section at the level of Mid Brain

Answers
18. Aqueduct of Sylvius
...
27
25

24
Post Contrast sagittal T1 Wtd
M.R.I.
Section at the level of the
III Ventricle

Answers
23
26

23. Occipital Lob...
38
37
32
36

31

35

Post Contrast sagittal T1 Wtd
M.R.I.

30

Section at the level of Thalamus
29

Answers

34

28. Super...
41

40
Post Contrast sagittal T1 Wtd
M.R.I.

39

Section at the level of Corpus
Callosum

Answers
39. Splenium of corpus c...
44

43
Post Contrast sagittal T1 Wtd
M.R.I.

42

Section at the level of Body of
Corpus Callosum

Answers
42. Parietal Lob...
46

Post Contrast sagittal T1 Wtd
M.R.I.
Section above the Corpus Callosum
45

Answers
45. Parietal Lobe
46. Frontal Lobe
...
Normal anatomical structure of
head on MRI
T2WI
T1WI
Flair sequence
T2WI(coronal section )
T1WI ( sagittal section )

Corpus callosum; optic chiasm; pituitary gland; medulla oblongata
MRI diagnosis of brain vascular
diseases
• Intra cerebral Hemorrhage
• Cerebral Infarction
• Intracranial Aneurysm
Brain bleed (hemorrhage)
• Causes : high blood pressure,
vascular malformation and tumor
• Stage : acute, sub acute, chron...
MRI appearances of hemorrhage at
different stage
• Acute hemorrhage

MRI - iso-intensity on T1WI, slightly low or low
inte...
acute/subacute hemorrhage
acute

subacute

T2WI

T1WI
Chronic intracranial hemorrhage
MRI diagnosis of cerebral infarction
MR appearances of cerebral
infarction
• High signal intensity at Acute , subacute and
chronic stage on T2WI because of inc...
MR&CT appearances of acute
cerebral infarction
T2WI

MR:44396

T1WI

Flair
MR&CT appearances of acute cerebral
infarction

MR:44396

T2WI

T1WI

Flair
Acute infarction
Acute
infarction
Acute infarction
DWI
Subacute/chronic infarction—T2WI
T2WI--Coronal
Chronic infarction at brain stem and
cerebellum—T2WI
Chronic infarction at brain stem and
cerebellum—T1WI
MRI diagnosis of head
trauma
The types of head trauma





Skull fracture
traumatic cerebral swelling
brain contusions
Intracranial bleed of trauma...
MR diagnosis of cranial trauma
Epidural hematoma :

‫ ٭‬direct

violence on skull

‫٭‬skull fracture and deformation
‫٭‬di...
MR FEATURES
‫ ٭‬shape of hematoma is biconvex
‫ ٭‬signal intensity of hematoma varies greatly depending
on times.
‫ ٭‬at a...
Subacute hematoma at
left frontal lobe
Subacute hematoma at
left frontal lobe
Subdural hematoma
‫٭‬Location: supratentorial convexity.
‫ ٭‬Caused by stretching and tearing of bridging veins.
‫ ٭‬Hemat...
Subacute Subdural Hematoma

Axial T1-weighted magnetic resonance imaging
demonstrates bilateral subacute subdural hematoma...
Subacute subdural hematoma at left
frontal-temporal area
Subacute subdural hematoma at left
frontal-temporal area
MR Features of brain contusion
‫ ٭‬Often

involve the temporal and frontal lobe.
• Temporal lobe lesions tend to lie just ...
MR appearances
‫ ٭‬MR is more sensitive than CT to find small contusion
because of easy to find edema caused by contusion....
Contusion and epidural hemorrhage at
both temporal lobe and frontal lobe
Contusion and epidural hemorrhage at
both temporal lobe and frontal lobe
Multiple contusions at both sides of
frontal and temporal lobes
Multiple contusions at both sides of
frontal and temporal lobes
INTRACRANIAL TUMORS
‫ ٭‬primary (80%) :originating

from cranial bone,

cranial meninges, brain tissues,
vessels, cranial ...
The types of intracranial tumors
• Intraaxial brain tumors :
1.glioma( astrocytoma and oligodendroglioma)
2.ependymoma
3.m...
The types of intracranial tumors
• Extraaxial brain tumors
1.meningioma
2.craniopharyngioma
3.pituitary tumor
4.nerve shea...
CT and MRI Signs for diagnosis
of intracranial tumors
Direct signs

、
1. tumor or occupying lesion.
2. abnormal density or...
Indirect signs
1. shift of near structures
2. edema in brain tissue near tumor
3. Intratumoral bleed
4. Intratumoral calci...
Astrocytoma
lower grading of astrocytoma , grading
I or II .
• Often in adult (20~40
years ) -- more occult in
cerebral
he...
Astrocytoma
MR :
Isointensity on T1WI , unclear border ,
high or slightly high signal intensity on T2WI
no or slight occup...
Grade I Astrocytoma

T1WI

T2WI
Grade II astrocytoma

T2W
MR:39547

Gd+

Gd+
Astrocytoma

high grading ( grading III or IV)
• Fast growing
• Occur in any age
Imaging appearances of high
grading astrocytoma
• Obvious occupying effects ,infiltrating growing
with unclear margin , gr...
Grade IV astrocytoma

T2W

MR:39985

T1W

Gd+
Grade IV

astrocytoma

T2W

MR:39985

Gd+

T2W

Gd+
Grading IV astrocytoma

MR : 53847
Brain metastasis
• Old age
• Single or multiple
• Multiple appearances on CT or MR, but
often shown in nodule
• Heterogene...
Multiple
metastases
Metastasis from lung cancer
uncontrast

contrast
Metastasis from lung cancer
uncontrast

contrast
Imaging of meningioma
• Round or hemishere mass occur mostly in convexity of
brain , especially sagittal sinus.
• Mass wit...
Right parietal meningioma

Contrast T1WI

Plain T1WI
T2WI AND
contrast T1WI
Meningioma

T2WI
T1WI
Gd-T1W
Acoustic schwannoma
• Benign tumor, occur mostly at middle age people,
approximately 7﹪~8﹪ of all primary intracranial neo...
Left acoustic
schwannoma
Left acoustic schwannoma

T2WI

T1WI

Contrast T1WI
Left acoustic
schwannoma
Mr imaging of brain
Upcoming SlideShare
Loading in...5
×

Mr imaging of brain

3,689

Published on

Published in: Health & Medicine, Technology
1 Comment
9 Likes
Statistics
Notes
No Downloads
Views
Total Views
3,689
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
503
Comments
1
Likes
9
Embeds 0
No embeds

No notes for slide

Mr imaging of brain

  1. 1. MR IMAGING OF BRAIN Muhammad Bin Zulfiqar PGR II SIMS/SHL New Radiology Department
  2. 2. Basics of MR • MR sequences • MR signal characteristic
  3. 3. MRI----conventional sequences • SE sequence ( spin echo ) – T1-weighted,T1-WI TR: 200-800ms TE:15-30ms – T2-weighted,T2-WI TR:1500-2000ms TE:60-150ms – Proton Density,N(H) ) TR:1500-2500ms TE:15-30ms • IR sequence ( inversion recovery sequence ) TR ( short ) TE ( short ) TI ( short )
  4. 4. MR signal characteristics • SE sequences : – T1-WI: highest signal on fat tissue ,better for showing anatomical structures – T2-WI: highest signal in liquid, better for detecting lesions – N ( H ) Density(H): for characteristics of lesions • GRE sequence : flip angle , fast scan • IR sequence : separation between of fat and liquid
  5. 5. MR signal characteristics T2WI T1WI
  6. 6. MR signal characteristics Fat supression Liquid supression
  7. 7. THREE DIMENSIONAL BRAIN ANATOMY
  8. 8. 5 3 Post Contrast sagittal T1 Weighted M.R.I. 2 Section at the level of Foramen Magnum 1 Answers 4 1. Cisterna Magna 2. Cervical Cord 3. Nasopharynx Fig. 1.1 Post Contrast Axial MR Image of the brain 4. Mandible 5. Maxillary Sinus
  9. 9. Post Contrast sagittal T1 Wtd M.R.I. Section at the level of medulla 6 Answers 7 Fig. 1.2 Post Contrast Axial MR Image of the brain 6. Medulla 7. Sigmoid Sinus
  10. 10. 14 13 12 Post Contrast sagittal T1 Wtd M.R.I. 11 17 10 16 15 Section at the level of Pons Answers 9 13. Internal Carotid Artery 14. Cavernous Sinus 10. IV Ventricle Fig. 1.3 Post Contrast Axial MR Image of the brain 8. Cerebellar Hemisphere 9. Vermis 8 15. Middle Cerebellar Peduncle 11. Pons 12. Basilar Artery 16. Internal Auditory Canal 17. Temporal Lobe
  11. 11. 20 22 19 18 21 Post Contrast sagittal T1 Wtd M.R.I. Section at the level of Mid Brain Answers 18. Aqueduct of Sylvius 19. Midbrain 20. Orbits Fig. 1.4 Post Contrast Axial MR Image of the brain 21. Posterior Cerebral Artery 22. Middle Cerebral Artery
  12. 12. 27 25 24 Post Contrast sagittal T1 Wtd M.R.I. Section at the level of the III Ventricle Answers 23 26 23. Occipital Lobe 24. III Ventricle 25. Frontal Lobe Fig. 1.5 Post Contrast Axial MR Image of the brain 26. Temporal Lobe 27. Sylvian Fissure
  13. 13. 38 37 32 36 31 35 Post Contrast sagittal T1 Wtd M.R.I. 30 Section at the level of Thalamus 29 Answers 34 28. Superior Sagittal Sinus 29. Occipital Lobe 33 28 33. Thalamus 34. Temporal Lobe 30. Choroid Plexus within the 35. Internal Capsule occipital horn Fig. 1.6 Post Contrast Axial MR Image of the brain 36. Putamen 31. Internal Cerebral Vein 37. Caudate Nucleus 32. Frontal Horn 38. Frontal Lobe
  14. 14. 41 40 Post Contrast sagittal T1 Wtd M.R.I. 39 Section at the level of Corpus Callosum Answers 39. Splenium of corpus callosum 40. Choroid plexus within the Fig. 1.7 Post Contrast Axial MR Image of the brain body of lateral ventricle 41. Genu of corpus callosum
  15. 15. 44 43 Post Contrast sagittal T1 Wtd M.R.I. 42 Section at the level of Body of Corpus Callosum Answers 42. Parietal Lobe Fig. 1.8 Post Contrast Axial MR Image of the brain 43. Body of the Corpus Callosum 44. Frontal Lobe
  16. 16. 46 Post Contrast sagittal T1 Wtd M.R.I. Section above the Corpus Callosum 45 Answers 45. Parietal Lobe 46. Frontal Lobe Fig. 1.9 Post Contrast Axial MR Image of the brain
  17. 17. Normal anatomical structure of head on MRI
  18. 18. T2WI
  19. 19. T1WI
  20. 20. Flair sequence
  21. 21. T2WI(coronal section )
  22. 22. T1WI ( sagittal section ) Corpus callosum; optic chiasm; pituitary gland; medulla oblongata
  23. 23. MRI diagnosis of brain vascular diseases • Intra cerebral Hemorrhage • Cerebral Infarction • Intracranial Aneurysm
  24. 24. Brain bleed (hemorrhage) • Causes : high blood pressure, vascular malformation and tumor • Stage : acute, sub acute, chronic
  25. 25. MRI appearances of hemorrhage at different stage • Acute hemorrhage MRI - iso-intensity on T1WI, slightly low or low intensity on T2WI( ideally MR was poor than CT for Acute hemorrhage ). • Sub acute hemorrhage MRI - iso- or high signal intensity on T1WI, iso- or slightly high signal intensity on T2WI. • Chronic hemorrhage MRI - high signal intensity both on T1WI/T2WI.
  26. 26. acute/subacute hemorrhage acute subacute T2WI T1WI
  27. 27. Chronic intracranial hemorrhage
  28. 28. MRI diagnosis of cerebral infarction
  29. 29. MR appearances of cerebral infarction • High signal intensity at Acute , subacute and chronic stage on T2WI because of increment of fluid at infarction. • Iso-intensity at acute stage , iso- or slightly low intensity at subacute stage, low intensity at chronic stage on T1WI. • Flair and DWI sequences are more sensitive for detecting acute infarction.
  30. 30. MR&CT appearances of acute cerebral infarction T2WI MR:44396 T1WI Flair
  31. 31. MR&CT appearances of acute cerebral infarction MR:44396 T2WI T1WI Flair
  32. 32. Acute infarction
  33. 33. Acute infarction
  34. 34. Acute infarction DWI
  35. 35. Subacute/chronic infarction—T2WI
  36. 36. T2WI--Coronal
  37. 37. Chronic infarction at brain stem and cerebellum—T2WI
  38. 38. Chronic infarction at brain stem and cerebellum—T1WI
  39. 39. MRI diagnosis of head trauma
  40. 40. The types of head trauma     Skull fracture traumatic cerebral swelling brain contusions Intracranial bleed of trauma – – – – Epidural hematoma Subdural hematoma Subarachnoid hemorrhage Intracerebral hematoma
  41. 41. MR diagnosis of cranial trauma Epidural hematoma : ‫ ٭‬direct violence on skull ‫٭‬skull fracture and deformation ‫٭‬direct laceration or tearing of meningeal arteries ‫ ٭‬local hematoma ,not across cranial suture ‫٭‬shape of duple convex mirror
  42. 42. MR FEATURES ‫ ٭‬shape of hematoma is biconvex ‫ ٭‬signal intensity of hematoma varies greatly depending on times. ‫ ٭‬at acute stage ( 0~2 days ), iso-intensity on T1WI , low intensity on T2WI. ‫٭‬at subacute stage ( 3~14 days ), becoming high signal intensity from rim to center on T1WI, still low signal intensity at 6~8 days and high signal intensity after 8 day on T2WI. ‫ ٭‬at chronic stage (14 days later) , high signal intensity on both T1WI and T2WI for quite long times (may be several months)
  43. 43. Subacute hematoma at left frontal lobe
  44. 44. Subacute hematoma at left frontal lobe
  45. 45. Subdural hematoma ‫٭‬Location: supratentorial convexity. ‫ ٭‬Caused by stretching and tearing of bridging veins. ‫ ٭‬Hematoma is located between dura mater and arachnoid. Often quite large extent , across cranial suture. ‫ ٭‬MR appearances : shape of hematoma semilunar , signal changes of hematoma similar to epidural hematoma at different stages.
  46. 46. Subacute Subdural Hematoma Axial T1-weighted magnetic resonance imaging demonstrates bilateral subacute subdural hematomas with T2-weighted magnetic resonance imaging in a increased signal intensity. Areas of intermediate intensity patient with subdural hematoma shows blood products of differing ages. represent more acute hemorrhage into the subacute collections.
  47. 47. Subacute subdural hematoma at left frontal-temporal area
  48. 48. Subacute subdural hematoma at left frontal-temporal area
  49. 49. MR Features of brain contusion ‫ ٭‬Often involve the temporal and frontal lobe. • Temporal lobe lesions tend to lie just above the petrous bone or posterior to the greater sphenoid wing. • Frontal lobe lesions occur just above the cribriform plate, orbit, planum sphnoidale, and lesser sphenoid wing.
  50. 50. MR appearances ‫ ٭‬MR is more sensitive than CT to find small contusion because of easy to find edema caused by contusion. ‫٭‬hemorrhagic foci appear petechia or multiple confluent regions with high signal intensity. ‫ ٭‬easy to find contusion at brain stem.
  51. 51. Contusion and epidural hemorrhage at both temporal lobe and frontal lobe
  52. 52. Contusion and epidural hemorrhage at both temporal lobe and frontal lobe
  53. 53. Multiple contusions at both sides of frontal and temporal lobes
  54. 54. Multiple contusions at both sides of frontal and temporal lobes
  55. 55. INTRACRANIAL TUMORS ‫ ٭‬primary (80%) :originating from cranial bone, cranial meninges, brain tissues, vessels, cranial nerves, pituitary gland, etc. glioma(50%) , meningioma(14%) , pituitary tumor (11%) , acoustic neuroma(7%) ‫٭‬secondary (20%) : metastasis , involved by from near structures. tumor
  56. 56. The types of intracranial tumors • Intraaxial brain tumors : 1.glioma( astrocytoma and oligodendroglioma) 2.ependymoma 3.medulloblastoma 4.hemangioblastoma 5.papilloma choroideum 6.metastases
  57. 57. The types of intracranial tumors • Extraaxial brain tumors 1.meningioma 2.craniopharyngioma 3.pituitary tumor 4.nerve sheath tumors-acoustic schwannoma 5.epidermorid cyst, dermoid cyst and hamartomas
  58. 58. CT and MRI Signs for diagnosis of intracranial tumors Direct signs 、 1. tumor or occupying lesion. 2. abnormal density or signal. 3. enhancement in different degree on enhanced scan.
  59. 59. Indirect signs 1. shift of near structures 2. edema in brain tissue near tumor 3. Intratumoral bleed 4. Intratumoral calcification 5. bone changes
  60. 60. Astrocytoma lower grading of astrocytoma , grading I or II . • Often in adult (20~40 years ) -- more occult in cerebral hemisphere , grading II , solid • child– less seen , more in cerebellum , grading I, cyst
  61. 61. Astrocytoma MR : Isointensity on T1WI , unclear border , high or slightly high signal intensity on T2WI no or slight occupying effect , no or slight enhancement.
  62. 62. Grade I Astrocytoma T1WI T2WI
  63. 63. Grade II astrocytoma T2W MR:39547 Gd+ Gd+
  64. 64. Astrocytoma high grading ( grading III or IV) • Fast growing • Occur in any age
  65. 65. Imaging appearances of high grading astrocytoma • Obvious occupying effects ,infiltrating growing with unclear margin , growing across lobe and hemisphere. • Necrosis, cyst , bleed. • Obvious brain edema around tumor. • Obvious uneven or ring-like enhancement.
  66. 66. Grade IV astrocytoma T2W MR:39985 T1W Gd+
  67. 67. Grade IV astrocytoma T2W MR:39985 Gd+ T2W Gd+
  68. 68. Grading IV astrocytoma MR : 53847
  69. 69. Brain metastasis • Old age • Single or multiple • Multiple appearances on CT or MR, but often shown in nodule • Heterogeneous density or signal, central necrosis with lower density or signal on T1WI. • Ring-like or even enhancement • Obviously finger-like peritumoral edema
  70. 70. Multiple metastases
  71. 71. Metastasis from lung cancer uncontrast contrast
  72. 72. Metastasis from lung cancer uncontrast contrast
  73. 73. Imaging of meningioma • Round or hemishere mass occur mostly in convexity of brain , especially sagittal sinus. • Mass with clear margin which was encysted with cerebral spinal fluid and/or vessels. • Iso- or slightly high density on plain CT and low signal on T1WI, iso- or slightly high signal on T2WI, which was enhanced obviously and evenly. • A broad thickened dural-based margin which was called “tail sign” . • Edema may be not or obvious. • Local bone changes including destruction, thin or thickness.
  74. 74. Right parietal meningioma Contrast T1WI Plain T1WI
  75. 75. T2WI AND contrast T1WI
  76. 76. Meningioma T2WI T1WI Gd-T1W
  77. 77. Acoustic schwannoma • Benign tumor, occur mostly at middle age people, approximately 7﹪~8﹪ of all primary intracranial neoplasms. • Ovoid or tubular tumors may occur in the internal auditory canal and cerebellopontine angle cistern . • Tumor may be part of solid and cystic . • On Plain CT, solid part of tumor was iso-density ,and cystic part was low density. • Iso-intensity or low signal intensity were seen in solid or cystic part of tumor on T1WI, but high or very high signal intensity on T2WI,. • Obvious enhancement was seen on solid tumor. • Enlargement of internal auditory canal.
  78. 78. Left acoustic schwannoma
  79. 79. Left acoustic schwannoma T2WI T1WI Contrast T1WI
  80. 80. Left acoustic schwannoma
  1. A particular slide catching your eye?

    Clipping is a handy way to collect important slides you want to go back to later.

×