1. The document discusses imaging approaches for evaluating intramedullary spinal cord lesions. It outlines a systematic approach including assessing the lesion length, extent of cord involvement, location within the cord, cord swelling, and enhancement characteristics. 2. Differential diagnoses discussed include demyelinating diseases, tumors, vascular causes, and infections. Specific conditions like multiple sclerosis, neuromyelitis optica, transverse myelitis, and various tumor types are described. 3. Imaging features of different pathologies are provided to help differentiate between conditions like ependymoma, astrocytoma, ganglioglioma, and hemangioblastoma.

1. IMAGING IN SPINAL CORD
LESIONS
DR. NAVNEET RANJAN LAL

3. CROSS-SECTIONAL
ANATOMY

8. APPROACH TO INTRA-MEDULLARY
SPINAL CORD LESIONS

9. SYSTEMATIC APPROACH
On MR look for the following:
1. Short or Long segment ?
 Short segment involved (less than 2 segments) - MS
 Long segment involved - Transverse Myelitis, NMO and
ischemia
2. How much of the cord is involved on
transverse images ?
 Partial involvement - MS.
 Complete involvement (includes both halves of the
cord) - TM and NMO.

10. 3. Location of the involvement on transverse images ?
High resolution transverse images used to detect the
location within the cord.
 Posterior - MS, vitamin B12 deficiency,
 Lateral - in MS or
 Anterior - Arterial infarction.
4. Is the cord swollen ?
In TM and tumor the cord is swollen.
5. Is there enhancement ?
Many diseases show some enhancement, but the most
important thing is that astrocytoma has to be included in
the differential diagnosis.

11. DIFFERENTIAL DIAGNOSIS
1. Demyelinating diseases
 MS vs TM vs NMO
2. Tumor
 Demyelinating diseases vs. Astrocytoma.
 The other common spinal cord tumors do not cause
differential diagnostic problems
 Metastases to the cord are very uncommon.

12. 3. Vascular
Acute ischemia is typically seen as a complication of
aortic aneurysm surgery or catheterization.
Cause- venous hypertension or arterial steal (AV-
fistula).
4. Inflammatory
Vasculitis
5. Infection
Infection rarely involves the spinal cord.

15. TRANSVERSE INVOLVEMENT

16. MULTIPLE SCLEROSIS
• Etiology.
• Pathology.
• Clinical presentation.
• Revised McDonald's criteria.
• CSF finding.

17. ETIOLOGY
 Autoimmune Inflammation
 Environmental factor
 Genetic factors Demyelination
PATHOLOGY
 T-17 helper involved
 Triad - IDG
Remyelination Gliosis
(Oligodendrocyte) (Astrocyte)
Fibrosis so damage

18. TYPES
1. Radiologically isolated syndrome
2. Clinically isolated syndrome
3. Relapsing – remitting MS (85%)
4. Relapsing progressive MS (Secondary progressive)
5. Primary progressive MS
Secondary progressive Primary progressive
RRMS

22. NEUROMYELITIS OPTICA (DEVIC DISEASE)
 Etiology.
 Demographics.
 Spinal cord + optic nerve. (Relative sparing of the
brain)
 Diagnostic criteria.

23. NEUROMYELITIS OPTICA (DEVIC DISEASE)
 Autoimmune demyelinating disease induced by a
specific auto-antibody, the NMO-IgG.
 NMO preferentially affects the optic nerve and spinal
cord.
 Demyelination of the spinal cord looks like transverse
myelitis, i.e. often extensive over 4 -7 vertebral segments
and the full transverse diameter.
 Female: male = 9:1

26. BRAIN LESIONS IN NMO

27. ACUTE DISSEMINATED ENCEPHALOMYELITIS
 Etiology.
 Demographics.
 Anti-MOG IgG test- positive
 Clinical presentation.
 Imaging characterstics.

28. .
THE IMAGING FINDINGS IN THIS CASE ARE ALSO TYPICAL.
THERE IS SWELLING AND CORD INVOLVEMENT LIKE IN TM AND NO ENHANCEMENT

30. THE FOLLOW UP MR SHOWS THAT THE CORD HAS RETURNED TO
NORMAL AGAIN

31. TRANSVERSE MYELITIS
 Focal inflammatory disorder of the spinal cord resulting in
motor, sensory and autonomic dysfunction.
 Imaging findings:
 More than 2/3 of the cross sectional area is involved.
 Focal enlargement.
 T2WI hyperintensity.
 Enhancement + / -.
 Two forms of TM:
1. Acute partial transverse myelitis
2. Acute complete transverse myelitis

34. TUMORS OF THE SPINE

35. CLASSIFICATION
 Primary lesions are relatively infrequent compared
to metastatic disease
 MR is the primary imaging modality
Spinal tumors are subdivided according to their
point of origin:
 Intramedullary,
 Extramedullary – Intradural,
 Extradural.

36. Intramedullary Extramedullary Intradural, Extradural

37. I N T R A M E D U L L A RY T U M O R S
Single: Multiple:
 Ependymoma Hemangioblastomas,
 Myxopapillary ependymoma, Metastases
 Astrocytoma, Lymphoma
 Ganglioglioma,
 Hemangioblastoma,
 Paraganglioma

38. INTRADURAL-EXTRAMEDULLARY TUMORS
Single Multiple
 Meningiomas, All except Paraganglioma
 Nerve sheath tumors,
 Intradural metastases,
 Lymphoma/leukemia,
 Paraganglioma

39. EPIDURAL LESIONS:
 Angiolipoma
 Angiomyolipoma,
 Epidural lipomatosis,
 Lymphoma

40. EXTRADURAL TUMORS
Single: Multiple:
 Aneurysmal bone cyst, Metastatic disease
 Giant cell tumor, Hemangiomas
 Osteoblastoma, Multiple myeloma
 Osteochondromas, Lymphoma.
 Chordoma,
 Chondrosarcoma,
 Chondroblastoma,
 Metastasis,
 Hemangioma,
 Solitary Plasmacytoma,
 Lymphoma.

41. INTRAMEDULLARY TUMORS
 Rare, accounting for about 4-10 percent of all central
nervous system tumors.
 Intramedullary tumors include
1.Gliomas (ependymomas, astrocytomas and
gangliogliomas) and
2.Nonglial tumors (such as hemangioblastomas,
lymphoma and metastases).

42. SPINAL EPENDYMOMA
 MC spinal cord tumor seen in adult.
 Comprising 60% of all glial spinal cord tumors
 Peak incidence is in the fourth decade
 Increased incidence with NF-2

43. PATHOLOGY
 Arise from ependymal cells lining the central canal or cell
rests along the filum
 Six histological subtypes are recognized:
 cellular (MC)
 papillary
 clear cell
 tanycytic
 Myxopapillary
 melanotic (the least common type)

44. IMAGING FINDINGS
Plain radiograph
 scoliosis
 spinal canal widening
 vertebral body scalloping
 pedicle erosion
 laminar thinning
CT
 iso to slightly hyper-attenuating compared with normal
spinal cord
 intense enhancement with iodinated contrast
 large lesions cause scalloping of the posterior vertebral
bodies and neural exit foraminal enlargement

45. MRI
 Widened spinal cord
 Although unencapsulated, they are well-circumscribed
 Tumoral cysts are present in 22%. Non-tumoral cysts
are present in 62%
 Syringohydromyelia occurs in 9-50% of cases
 In contrast to intracranial ependymomas, calcification is
uncommon
 Average length of four vertebral body segments

46. Typical signal characteristics:
 T1: most are isointense to hypointense; mixed signal
lesions are seen if cyst formation, tumor necrosis or
hemorrhage has occurred
 T2: hyperintense
 peritumoural edema is seen in 60% of cases
 associated hemorrhage leads to the “cap sign”
 T1 C+ (Gd): virtually all enhance strongly, somewhat
inhomogeneously

48. • Cysts are a common associated finding
in the setting of an intramedullary spinal
tumour.
Non tumoral cyst Tumoral cyst
Location- poles of solid portion Within the solid component
Non enhancing Peripheral enhancing
Reactive dilatation of central canal -

49. MYXOPAPILLARY EPENDYMOMA
 Variant type
 Occurs predominantly in the filum terminale and/or
conus medullaris
 MC tumors of the cauda equina region.
 These are WHO grade I ependymal tumors
Signal characteristics
 T1
 usually isointense
 prominent mucinous component occasionally results in T1
hyperintensity
 T2
 Overall high intensity
 T1 C+ (Gd)
 enhancement is virtually always seen

52. SPINAL ASTROCYTOMA
 MC spinal cord tumor in children. 60% of pediatric
intramedullary tumors
 Associations with NF 1
 Characterized by hypercellularity and absence of a
surrounding capsule

53. Location
 Usually span multiple segments in craniocaudal extent,
with an average length of involvement of 4-7 vertebral
body segments
 Thoracic cord (67%), followed by cervical cord (49%),
are most common
 Involvement of entire spinal cord (holocord presentation)
- more common in children than in adults
 Isolated conus medullaris and filum terminale

54. Radiographic features
 Plain radiograph/CT
 posterior vertebral body scalloping or thinning of the pedicle
or laminae
 MRI
 arise from cord parenchyma they typically have an
eccentric location within the spinal cord.
 have poorly defined margins
 T1: isointense to hypointense
 T2: hyperintense
 T1 C+ (Gd)
 vast majority enhance (previously thought to be universally
enhancing )
 usually patchy enhancement pattern

56. 1. MC in adults
2. Central location in spinal canal
3. well-circumscribed
4. hemorrhage is common
 may rarely present as
a subarachnoid
hemorrhage
 Hemosiderin capping is
common
5. Scoliosis and bony
remodelling more common
6. Focal, intense homogeneous
contrast enhancement
7. More frequent and more
prominent cysts (intratumoral
and polar)
1. MC in children
2. Eccentric location in the
spinal canal
3. Ill-defined
4. hemorrhage is uncommon
5. bone changes are
infrequent
6. patchy irregular contrast
enhancement
7. involvement of the entire
cord diameter and longer
cord segments favors an
astrocytoma (i.e., if an
intramedullary neoplasm
involves the total spinal
cord, it is more likely to be
an astrocytoma )
Ependymoma Astrocytoma

57. Ependymoma Astrocytoma

58. GANGLIOGLIOMAS
 Composed of a mixture of ganglion cells and
neoplastic glial elements
 Majority of neoplastic glial cell types are of astrocytic
subtype.
 Second MC intramedullary tumor in the pediatric age group
 Mostly affect children between 1 and 5 years of age,
as do pilocytic astrocytomas.
 Cervical spine > thoracic region.

59.  Have a low malignant potential, slow growth, but they
have a significant propensity for local recurrence.
 Gangliogliomas tend to be extensive on presentation
 Occupy an average length of 8 vertebral segments,
compared with ependymomas and astrocytomas, which
average 4 vertebral segments in length.

60. Imaging
 Calcification most suggestive feature of gangliogliomas.
 Like astrocytomas, gangliogliomas tend to be
eccentrically located within the spinal cord.
 Tumoral cysts are more common in gangliogliomas
than in either astrocytomas or ependymomas
 Chronic bony changes, including scoliosis and erosions,
are often seen with gangliogliomas due to their relatively
slow growth

61.  T1:
 mixed signal intensity (due to the dual cellular elements of
the tumor and is a unique finding among spinal cord tumors)
 T2
 high intensity
 surrounding edema is uncommon
 T1 C+ (Gd): most demonstrate patchy enhancement,
 Gradient echo: calcification is common, and will appear
as areas of low signal with blooming

63. HEMANGIOBLASTOMAS
 Nonglial, highly vascular neoplasms of unknown cell
origin.
 Most of these tumors (75%) are intramedullary, they may
involve the intradural space or even be extradural.
 Thoracic spinal cord > cervical spinal cord.
 Mostly sporadic
 Approximately one-third of cases occur in association
with Von Hippel-Lindau disease.

64. IMAGING.
MR features depend on the size of the tumor.
 Small (<10 mm)-
 isointense on T1WI
 hyperintense on T2WI
 homogeneous enhancement,
 Large (>10mm) –
 hypo or mixed onT1WI
 heterogeneous on T2WI
 heterogeneous enhancement

65.  Hemangioblastoma larger than 24 mm is usually
accompanied by vascular flow-voids.
 Tumor is not likely to be a hemangioblastoma if it is 25 mm
or larger and is not associated with vascular flow voids on
MR images.
 Associated with syrinx that are usually more extensive than
those seen with ependymomas or astrocytomas.
 Hemangioblastomas are often multiple in Von Hippel-
Lindau disease

67. SPINAL PARAGANGLIOMA
 Tumors of neuroendocrine origin
 Third MC primary tumor to arise in the filum terminale (after
ependymoma and astrocytoma).
 WHO grade I tumors
 highly vascular masses, the majority (75%) of
paragangliomas are encapsulated
 Hemorrhage is common (third most common after
ependymoma and hemangioblastoma) and a low signal-
intensity rim (cap sign) may be seen on T2WI.

68. MRI
 T1: isointense
 T2
 hyperintense
 flow voids are typically seen along the surface of and
within the tumor nodule
 hemorrhage is common, leading to a hemosiderin cap
sign
 T1 C+ (Gd): intense enhancement is virtually
always seen

70. INTRAMEDULLARY LYMPHOMA
 Primary intramedullary spinal lymphomas are extremely
rare.
 These tumors are of the non-Hodgkin variety and can occur
in both the immunocompromised and immunocompetent
patients.
 The majority of these tumors occur in the cervical or
thoracic regions of the spinal cord

71.  They are solid tumors without necrosis.
 Marked T2 hyperintensity and enhance following
gadolinium administration.
 There is no associated syringomyelia.
 Clinically, these patients initially respond to steroid
treatment for a short time but usually recur after
treatment.

73. INTRAMEDULLARY METASTASES
 Intramedullary spinal cord metastases are rare.
 Usually involve the cervical cord.
 MC primary tumors that metastasize to the spinal cord
include lung, breast, colon, lymphoma and kidney.
 On MRI,
 T1- hypointense,
 T2-hyperintense and
 demonstrate homogeneous enhancement.
 The amount of surrounding edema is out of proportion to the
size of the lesion.

74. ARACHNOIDITIS
 Inflammation of the meninges and subarachnoid space.
Etiology
 infectious
 meningitis
 inflammatory
 intrathecal hemorrhage
 iatrogenic
 intrathecal drugs
 contrast media, e.g. Lipiodol, Pantopaque/Myodil -
controversial 3
 anesthetics
 steroids (accidental intrathecal injection)
 surgery

75. MRI
 As a result of inflammation, the nerve roots become adherent to
each other and to the theca.
 Three resultant morphological patterns have been described on
the basis of imaging
 type I: nerve roots are clumped together and distorted
 type II: nerve roots are adherent to the theca resulting in
an empty thecal sac sign
 type III: nerve roots and theca are clumped together into a
single soft tissue mass centrally within the spinal canal
(Pseudo cord sign)

77. INTRADURAL EXTRAMEDULLARY TUMORS

78. MENINGIOMA
 Female predominance with a peak occurrence in the fifth
and sixth decades.
 Multiple spinal meningiomas are seen in patients with NF-2.
 MC in the thoracic spine > craniocervical junction > lumbar
region.
 Although most thoracic and lumbar meningiomas are based
on the posterior dura, craniocervical ones may be anterior
or posterior in location.

79. MRI
 Well-circumscribed
 Broad-based dural attachment
 dural tail sign (60-70%)
 ginkgo leaf sign in meningiomas arising lateral or
ventrolateral to the spinal cord
 T1: isointense to slightly hypointense, possibly
heterogeneous
 T2: isointense to slightly hyperintense
 T1 C+ (Gd): moderate homogeneous enhancement
 Occasionally, densely calcified meningiomas are
hypointense on T1 and T2 and show only minimal
contrast enhancement.

81. SPINAL NERVE SHEATH TUMORS
 MC intradural extramedullary mass (58%)
 Spinal nerve sheath tumors include, in order of decreasing
frequency:
1. spinal schwannoma (30% of all intradural extramedullary
lesions and 65% of intradural extramedullary nerve sheath
tumors )
2. spinal neurofibroma
3. spinal ganglioneuroma
 Extradural (27%)
 Extradural & intradural component (15%) – dumbell
shaped
 Intramedullary (1%)

82. Radiographic features
 Schwannomas and neurofibromas are often
indistinguishable radiographically.
Plain radiograph
bony changes can be common on plain film and can include
 enlarged neural foramina.
 pedicle erosion
CT
 density varies from hypodense to slightly hyperdense
 vertebral body scalloping
 paraspinous soft tissue mass: (“dumbbell” and extradural
lesions)
 calcification and hemorrhage are rare

83. SPINAL SCHWANNOMAS
 Benign nerve sheath tumors
 typically arising from spinal nerve roots
 Generally solitary and round
 NF2 association
 Associated with hemorrhage, intrinsic vascular changes
(thrombosis, sinusoidal dilatation), cyst formation and fatty
degeneration
 Do not encase the adjacent nerve root.
 Displace the nerve root due to their asymmetric growth.

84. MRI
 T1: 75% are isointense, 25% are hypointense.
 T2: more than 95% are hyperintense (due to water
content), often with mixed signal
 T1 C+: virtually 100% enhance

86. SPINAL NEUROFIBROMA
 Benign peripheral nerve sheath tumors
 Multiple
 Association with neurofibromatosis even when single
 NF 1 association
 Not associated with hemorrhage and intrinsic vascular
changes
 Encase the dorsal nerve root
 Fusiform appearence

87. MRI
 T1: hypointense
 T2: hyperintense
 a hyperintense rim and central area of low signal (“target sign”) may
be seen; this is thought to be due to a dense central area of
collagenous stroma.
 although this sign is highly suggestive of neurofibroma, it is
occasionally also seen in schwannomas and malignant peripheral
nerve sheath tumors
 T1 C+ (Gd): heterogenous enhancement

90. INTRADURAL METASTASES
 Metastasis to the dura most commonly arise from breast
cancer, lung cancer and melanoma.
 Tumors of the central nervous system (glioblastoma
multiforme and posterior fossa ependymomas) may
produce “drop metastases.”
 Metastatic lesions appear as small, round, multifocal
lesions that enhance and stud the surface of the cord.

91. EPIDURAL LESIONS:
 Angiolipoma
 Epidural lipomatosis,
 Lymphoma
 Epidural hematoma
 Hirayama’s disease
 Benign cyst
 Extramedullary hematopoiesis

92. PATHOLOGIES AFFECTING POSTERIOR SPINAL EPIDURAL SPACE
 Degenerative:
• Herniated disc,
• Hypertrophied ligamentum flavum and facetal arthropathy,
Synovial cyst
 Infective:
• Pyogenic abscess, tuberculous abscess, fungal infection.
 Neoplastic:
 i) Benign
• Lipoma/lipomatosis, angiolipoma, hemangioma,
• paraspinal arteriovenous malformation/fistula, arachnoid cyst,
dermoid, epidermoid cyst
 ii) Malignant
• Lymphoma, metastases.
 Miscellaneous:
• Epidural hematoma (spontaneous or post traumatic),
• Dilated venous plexus in collateral pathway in IVC
• obstruction,
• Hirayama’s disease

93. EPIDURAL LIPOMATOSIS
 Refers to an excessive accumulation of fat within
the spinal epidural space resulting in compression of the
thecal sac.
 Lumber region most frequently affected
The underlying causes:
 Glucocorticoid excess
 long term steroid administration (e.g. for asthma): 55% - most
common
 endogenous Cushing syndrome: 3%
 Obesity: 25%
 Idiopathic: 17%

94. IMAGING FINDINGS
MRI
 Excess of fat seen in the extradural space.
 Dural sac can appear narrowed or even resemble
a "Y" shaped configuration.
 Signal characteristics follow fat on all sequences:
 T1: high signal
 T1 (FS): shows fat suppression
 T2: high signal
 Epidural fat thickness > 7mm is diagnostic

96. DISC HERNIATION
 Refers to the displacement of intervertebral disc material
beyond the normal confines of the disc but involving less than
25% of the circumference (to distinguish it from a disc bulge).
 Commonly they are divided into protrusion vs. extrusion:
 protrusion
 base wider than herniation
 confined to disc level
 outer annular fibers intact
 extrusion
 base (a.k.a. neck) narrower than herniation 'dome'
 may extend above or below endplates or adjacent vertebrae
 complete annular tear with passage of nuclear material beyond disc
annulus
 disc material can then migrate away from annulus or
become sequestered

98. SPINAL EPIDURAL ABSCESS
 Represents infection of the epidural space.
 Risk factors include
 Comorbidities: diabetes mellitus, alcohol abuse, HIV infection
 Spinal abnormality or intervention: degenerative joint
disease, trauma, surgery or procedure
 potential local or systemic source of infection: IVDU
 Classical symptoms include:
 spinal pain
 fever
 neurological deficit

99. RADIOGRAPHIC FEATURES
MRI
 There are two main patterns, with distinct imaging
appearances
 Phlegmonous Stage of infection results in
homogeneous enhancement of the abnormal area
 Liquid Abscess surrounded by inflammatory tissue
which shows varying degree of peripheral enhancement
with gadolinium

101. SPINAL EPIDURAL HEMATOMA
 Most common in the cervicothoracic region,
 Usually posterior to the thecal sac over 2-4 vertebral
levels
 Most commonly spontaneous venous bleeds, often in
the setting of coagulopathy or over-anticoagulation
 Located between the dura propria (visceral layer) and
periosteum

102. Etiology
 spontaneous (most common)
 especially in the context of a bleeding disorder or over-
anticoagulation
 trauma, e.g. vertebral fracture
 iatrogenic, e.g. lumbar puncture, epidural anesthesia
 spinal arteriovenous malformations or other vascular
anomalies
 spinal tumors
 pregnancy

103. CT
 non-contrast: hyperdense (50-70 HU) extradural mass
MRI
 Signal characteristics will vary on the age of the blood. Signal
characteristics of acute spinal EDH
 T1: isointense or hyperintense to spinal cord
 T2: heterogeneously hyperintense to spinal cord with
hypointense foci
 T2*: blooming artifact

105. EPIDURAL ANGIOLIPOMA
 Rare, benign lesion that contains mature adipose and vascular
elements
 Usually noninfiltrating
 Occurs in the posterior epidural space
 Spinal angiolipoma divided into two types based on the ratio of
fat to vessels On MRI
 Type 1: These lesions are predominantly fatty, and hence appear
hyperintense on T1W and T2W images
 Type 2: Vascular component forms more than 50% of the lesion and is
surrounded by fat. These may appear heterogenous on T1W and T2W
images and most of the lesion shows intense enhancement.

106.  Imaging findings:
 More than 2/3 of the cross sectional area is involved.
 Focal enlargement.
 T1: isointense or hypointense
 T2WI hyperintensity
 Enhancement + / -.

108. SPINAL ARACHNOID CYST
 These are CSF-filled sacs contained by the arachnoid
mater.
 may be congenital or acquired.
 Secondary arachnoid cysts are usually due to trauma,
hemorrhage, inflammation, surgery or lumbar puncture
 MRI
 T1: CSF intensity
 T2: CSF intensity, may even be brighter than CSF, since there is
no signal loss from pulsation/flow
 T1 C+ (Gd): no contrast enhancement
 phase-contrast imaging: decreased CSF flow within the cyst
 DWI: no evidence of restricted diffusion

111. EXTRAMEDULLARY HEMATOPOIESIS
 Is a response to the failure of erythropoiesis in the bone
marrow
Etiology
 Myeloproliferative disorders
 chronic myelogenous leukemia
 polycythemia vera
 essential thrombocytosis
 Myelofibrosis with myeloid metaplasia
 Hodgkin disease
 Hemoglobinopathies
 sickle cell disease
 thalassemia
 hereditary spherocytosis

112.  Extramedullary hematopoiesis commonly involves liver,
spleen, kidneys, and paraspinal location in posterior
mediastinum.
 Rarely, it may occur in the epidural space resulting in
cord compression.
 MRI –
 appears as well-defined lobulated masses embedded in the
epidural space. These
 T1W - isointense to cord ,
 T2W - variable signal on
 none-to-minimal post-contrast enhancement.
 Vertebrae may show diffuse marrow abnormality

114. HIRAYAMA’S DISEASE
 It is a flexion-induced myelopathy predominantly affecting C8–T1 in an
asymmetric manner
 The ventral displacement of taut dura during flexion causes cord
compression and microcirculatory changes
 MRI is the imaging modality of choice
 Imaging features in a neutral position include loss of attachment of dura
to lamina
 Asymmetric lower cervical cord atrophy with increase in T2 signal, and
loss of cervical lordosis.
 Loss of dural attachment has been ranked with 100% specificity
 Flexion MRI reveals forward migration of dura with enlargement of
posterior epidural space seen as a crescentic region of high signal both
on T1 and T2