Infectious/inflammatory/wm Dz Neuroradiology

Front 1

NeuroSarcoid
1. Typical symptoms
2. Imaging appearance
3. Distinction from infectious meningitis?

Back 1

1. cranial nerve palsies, chronic meningitis, hypothalamic-pituitary dysfunction
2. nodular leptomeningeal infiltration, hypophysitis, centered around skull base, cerebellum, sellar/parasellar region
3. More nodular – though both may have diffuse basilar cistern enhancement

Front 2

Basal meningitis a/w lacunar infarcts – think?

Back 2

Tuberculous meningitis

Front 3

Intracranial Extension of Sphenoid Sinus Infection
1. Agents
2. Route
3. Sequelae

Back 3

1. Mucor, Aspergillosus, Bacterial
2. Through thin sphenoid sinus wall, epidural abscess
3. Cavernous sinus thrombosis, cranial nerve palsy, carotid artery occlusion, infarcts

Front 4

Tolosa-Hunt Syndrome
1. What is it?
2. symptoms
3. Complications

Back 4

1. Pseudotumor from orbital apex to cavernous sinus
2. Painful ophthalmoplegia, visual deficits
3. avernous sinus thrombosis, carotid arteritis

Front 5

Temporal Lobe “Edema” – DDx

Back 5

1. HSV Encephalitis
2. Viral Meningitis
3. Acute/subacute infarct
4. Gliomatosis/Infiltrative Astroctyoma
5. Limbic Encephalitis
6. Cysticercosis
7. SLE
8. PML
9. Transverse Sinus Thrombosis
10. Primary angiitis of CNS

Front 6

Confluent Zones of White Matter Abnormality – DDx

Back 6

1. PML
2. HIV Encephalitis
3. Radiation Change
4. Chemotherapy toxicity
5. Territorial Infarct
6. Aging/chronic microangiopathic change
7. Leukodystrophy
8. MS/ADEM
9. Vasculitis
10. Venous Hypertension
11. Encephalitis
12. PRES
13. Unilateral Megalencephaly
14. Band heterotopia

Front 7

Multifocal Pathcy Lesions Involving White Matter – DDx

Back 7

1. MS/ADEM
2. PML
3. Microangiopathic Disease
4. Sjogren’s syndrome
5. SLE
6. Hypertensive encephalopathy
7. Primary CNS angiitis
8. Dural Venous Thrombosis
9. Tuberous Sclerosis

Front 8

Multiple Punctate Lesions in White Matter

Back 8

1. Microangiopathic Disease
2. VR spaces
3. MS/ADEM
4. Mets
5. Lyme Disease
6. Sarcoidosis
7. Border Zone infarcts
8. Small artery infarcts
9. Vasculitis
10. Diffuse Axonal Injury

Front 9

Symmetric Lesions within Deep Nuclei - DDx

Back 9

1. Age-related calcifications
2. Liver/Renal Disease
3. Fahr’s Disease
4. CO poisoning/ other toxicity
5. Mets
6. MS
7. Vasculitis
8. Bithalamic astroctyoma
9. SLE
10. Leigh Disease
11. Maple Syrup Urine Disease
12. Adrenoleukodystrophy
13. Old Hypoxic/Ischemic Injury
14. Hallervorden-Spatz Disease
15. Hepatocerebral degeneration
16. Amyotrophic Lateral Sclerosis
17. Extrapontine Myelinolysis
18. Parkinson Disease
19. Deep Venous Thrombosis
20. Basilar artery ischemia/Thalamoperforator/Percheron
21. Viral Encephalitis
22. Anoxia
23. NF spots

Front 10

Leptomeningeal Enhancement – DDx

Back 10

1. Chemical meningitis
2. Bacterial/mycobacterial/viral meningitis
3. Sarcoidosis
4. Meningeal Carcinomatosis
5. CSF tumor seeding
6. Moya-Moya
7. Leukemia
8. Sturge-Weber syndrome
9. Acute infarct

Front 11

Thickened Dural Enhancement – DDx

Back 11

1. CSF Hypotension
2. Dural metastasis
3. Post-operative change
4. Idiopathic pachymeningitis
5. Meningioma
6. Subdural empyema
7. Sarcoidosis
8. Systemic Lymphoma

Front 12

Ventricular Enlargement – DDx

Back 12

1. Obstructive hydrocephalus – mass
2. Aqueductal stenosis
3. NPH
4. Decreased resorption s/p hemorrhage, infection, tumor
5. CSF overproduction due to CPP
6. Ventricular trapping due to herniation/shift
7. Ex Vacuo dilatation – infarct
8. Ex Vacuo dilatation – PVL
9. Colpocephaly due to CC dysgenesis
10. Huntington’s disease
11. Hydranencephaly
12. Holoprosencephaly
13. Porencephaly
14. Septo-Optic Dysplasia

Front 13

Intracranial Pneumocephalus – DDx

Back 13

1. Post-surgical – hypophysectomy, sinus surgery
2. Trauma/fracture
3. Sinus Osteoma
4. Neoplasm invading sinus (Pituitary adenoma, epidermoid, paranasal sinus malignancy)
5. Mucocele
6. Sinus/mastoid infection (gas forming organism)

Front 14

Complications of Intracranial Pneumocephalus – DDX

Back 14

1. Tension
2. CSF rhinorrhea
3. Meningitis, epidural or brain abscess
4. Extracranial pneumocephalus (collection in subaponeurotic space

Front 15

Cerebral Atrophy – Types and DDx

Back 15

1. Diffuse
2. Focal
3. Reversible Process simulating atrophy

Front 16

Diffuse Cerebral Atrophy – DDX

Back 16

1. Trauma
2. RTX
3. Drugs – dilantin, steroids, MTX, marijuana, hard drugs, chemotx
4. Demyelinating disease – MS, encephalitis
5. Degenerative Disease – Alz, Picks, Jakob-Creutzfeld
6. Cerebrovascdular disease – SVID, multiple infarcts
7. Advancing age, anorexia, renal failure

Front 17

Focal Brain Atrophy – DDX

Back 17

1. Vascular
2. chemical
3. metabolic
4. traumatic
5. idiopathic (Dyke-Davidoff-Mason syndrome)

Front 18

Reversible Process Simulating Atrophy (in younger people) – DDx

Back 18

1. Anorexia Nervosa
2. alcoholism
3. catabolic steroid tx
4. pediatric malignancy

Front 19

Cerebellar Atrophy – DDx

Back 19

1. Generalized atrophy (cerebral + cerebellar)
2. Cerebellar atrophy without cerebral atrophy
a. Olivopontocerebellar degeneration/Marie ataxia/Friedreich ataxia – young adult onset ataxia
b. Ataxia-telangiectasia
c. Ethanol toxicity – predominantly vermis/midline
d. Phenytoin-toxicity – predominantly cerebellar hemispheres
e. Idiopathic degen 2º carcinoma (paraneoplastic) – usually oat cell carcinoma of lung
f. RTX
g. Focal cerebellar atrophy – infarction, traumatic injuery

Front 20

What malignancy most common to cause cerebellar degeneration (paraneoplastic)?

Back 20

1. Oat cell Ca of lung (small cell)

Front 21

Ventriculomegaly – 3 categories DDx

Back 21

1. Macrocephaly
2. Microcephaly
3. Normocephaly

Front 22

Ventriculomegaly with Macrocephaly – DDx

Back 22

(Increased IVP)
1. CSF flow obstruction
a. Communicating hydrocephalus
b. Non-communicating hydrocephalus
2. Overproduction of CSF
3. Neoplasm

Front 23

Ventriculomegaly with Microcephaly – DDx

Back 23

(Normal IVP)
1. Primary failure of brain growth
a. Dysgenesis
i. Holoprosencephaly
ii. Aneuploid syndromes (trisomies)
iii. Migrational (<6 layers)
b. Environment – alcohol, drugs, toxins
c. Infection – TORCH
2. Loss of brain mantle
d. Infection: Torch
e. Vascular accident:
i. Hydranencephaly
ii. Schizencephaly
iii. Porencephaly
f. Hemorrhage
i. Porencephaly
ii. Leukomalacia

Front 24

Colpocephaly – DDx

Back 24

1. Callosal dysgenesis/agenesis
2. Arnold-chiari Malformation
3. Holoprosencephaly

Front 25

Midline Cystic Structures - DDx

Back 25

1. Cavum septi pellucidi – anterosuperior to anterior ipllar of fornix
2. Cavum vergae – posterior to columns of fornix
3. Cavum Veli Interpositi – extension of quad plate cistern above third ventricle
4. Colloid cyst
5. arachnoid cyst

Front 26

Posterior Fossa Cystic Malformation - DDx

Back 26

1. Dandy-Walker Variant
2. Arachnoid Cyst
3. Megacisterna Magna
4. Epidermoid

Front 27

Diffusely swollen Hemispheres – DDx

Back 27

1. Metabolic
a. Metabolic encephalopathy – uremia, reye syndrome, ketoacidosis
b. Anoxia: cardiopulmonary arrest, near drowning, smoke inhalation, ARDS
2. Neurovascular
c. Hypertensive encephalopathy
d. Superior sagittal sinus thrombosis
e. Head trauma
f. Pseudotumor cerebri
3. Inflammation
g. Herpes encephalitis, CMV, toxoplasmosis

Front 28

Edema of Brain – three types and scenarios – DDX

Back 28

1. Vasogenic edema – inflammation, neoplasm, mets, hemorrhage, infarction
2. Cytotoxic edema – ischemic, anoxia
3. Interstitial Edema – increase in IVP with transependymal flow of CSF à increase in periventricular interstitial spaces à blurring of GM/WM, compressed slitlike lateral ventricles, compression of sulci/cisterns i.e. diffuse cerebral edema)

Front 29

Cholesterol-Containing CNS Lesions – DDX

Back 29

1. Epidermoid Inclusion Cyst
2. Cholesterol Granuloma
3. Aquired epidermoid of middle ear
4. Congenital cholesteatoma of middle ear
5. Craniopharyngioma

Front 30

Periventricular Hypodensity – DDx

Back 30

1. Encephalomalacia
2. Porencephaly
3. Resolving hematoma
4. Cystic Tumor

Front 31

Suprasellar Low-density Lesion with Hydrocephalus – DDx

Back 31

1. Cyst
a. Arachnoid cyst
b. Ependymal cyst of 3rd ventricle
c. Parasitic cyst of 3rd venticle (cysticercosis)
d. Dilated 3rd ventricle (aqueductal stenosis)
2. Cystic Mass
e. Epidermoid
f. Hypothalamic pilocystic astrocytoma
g. Cystic craniopharyngioma

Front 32

Mesencephalic Low-density Lesion

Back 32

1. Normal – decussation of superior cerebellar peduncles at level of inferior colliculi
2. Syringobulbia – Arnold-chiari, trauma, synringomyelia exension
3. Brainstem infarction
4. Central pontine myelinolysis
5. Brainstem glioma
6. Mets
7. Graunoma in TB/Sarcoid

Front 33

Intracranial Hemorrhage

Back 33

ITHACANS
1. Infarction – hemorrhagic
2. Trauma
3. Hypertension
4. AVM
5. Coagulopathy
6. Aneurysm
7. Neoplasm
8. Sinus thrombosis

Front 34

Increased Density of Falx

Back 34

1. SAH
2. Interhemispheric Subdural hemorrhage
3. Diffuse cerebral edema (relative)
4. Dural calcifications (CRF hypercalcemia, basal cell nevus syndrome, hyperPTH)
5. Normal falx (can be normal dense in peds)

Front 35

Dense Cerebral Mass – DDX

Back 35

1. Tumor
a. Meningioma
b. Lymphoma
c. Hemorrhagic or calcified/mucinous met
d. Medulloblastoma
2. Vessel
e. Aneurysm
f. Hematoma
g. AVM

Front 36

Dense Lesion Near Foramen of Monro

Back 36

1. Intraventricular Lesion
a. Colloid cyst
b. CPP/granuloma
c. Meningioma
d. AVM of septal, thalamostriate, internal cerebral veins
2. Periventricular Mass
e. Lymphoma
f. TS tuber/SEGA
g. Met (mucinous adenoca, hemorrhagic met)
h. GBM of septum pellucidum
3. Masses projecting superiorly from base of skull
i. Pituitary adenoma
j. Craniopharyngioma
k. Aneurysm
l. Doliectatic basilar artery

Front 37

Intracranial Calcifications

Back 37

PINEEAL
1. Physiologic
2. Infection – TORCH, healed abscess, hydatic cyst, tuberculoma, cysticercosis
3. Neoplasm –
4. Endocrine – HyperPTH, hypervitaminosis D, hypoPTH, pseudohypoPTH, CO poisoning, lead poisoning
5. Embryologic – Neurocutaneous syndromes (TS, Struge-Weber, NF), Fahr dz, Cockayne syndrome, Basac cell nevus syndrome
6. Arteriovenous – AVM, aneurysm, hemangioma, subdural hematoma
7. Leftover Ls – lipoma, lipoid proteinosis, lissencephaly

Front 38

CMV vs Toxo calcifications -

Back 38

1. CMV – CircuMVentricular
2. Toxo - inTraparenchymal

Front 39

Neoplasms with Calcification

Back 39

Ca+ Come
1. Craniopharyngioma
2. Astrocytoma, aneurysm
3. CPP
4. Oligodendroglioma
5. Meningioma, medulloblastoma
6. Ependymoma

Front 40

Parasellar mesial-temporal/hippocampal calcification – bilaterally symmetric, bean-shaped, think ___ ?

Back 40

Lipoid proteinosis

Front 41

Physiologic Intracranial Calcification

Back 41

1. Pineal calcification (pineal calc <6yo or >10mm suggests pineal neoplasm (teratoma/pineoloma)
2. Habenula
3. Choroid plexus
4. Dura, falx, tentorium
5. Petroclinoid ligament – b/w tip of dorsum sella and apex of petrous bone
6. Interclinoid Ligament
7. ateriosclerosis of ICA
8. Basal ganglia

Front 42

Periventricular Calcification – Peds

Back 42

1. Congenital Infection: CMV, toxo
2. TS

Front 43

Gyral Enhancement

Back 43

1. Meningeal Tumor
a. meningeal carcinomaotosis from systemic tumor (breast, SCLCA, malignant melanoma, lymphoma, leukemia
b. Primary CNS tumor seeding – GBM, Ependymoma, JPA, Pineoblastoma, medulloblastoma
2. Meningitis – pyogenic, Tb, fungal, cysticercosis, sarcoidosis
3. Sequela of SAH – fibroblastic proliferation
4. Subacute Infarct

Front 44

Gyral Enhancement – DDx

Back 44

CAL MICE
1. Cerebritis
2. AVM (bleed)
3. Lymphoma
4. Meningitis
5. Infarct
6. Carcinomatosis
7. Encephalitis

Front 45

Enhancing Ventricular Margins – DDx

Back 45

1. Subependymal spread of Metastatic Tumor
a. Bronchogenic Ca (esp SCLCA)
b. Melanoma
c. Breast Ca
2. Subependymal seeding of CNS primary
d. Glioma
e. Ependymoma
3. Ependymal seeding of CNS primary
f. Medulloblastoma
g. Germinoma
4. Lymphoma
5. Inflammatory Ventriculitis

Front 46

Ring-enhancing Lesion of Brain

Back 46

1. Neoplasm
a. Primary – high grade glioma, meningioma, lymphoma, leukemia, pituitary macroadenoma, acoustic neuroma, craniopharyngioma
b. Mets
c. Sarcoma
2. Infection
d. Abscess: pyogenic, fungal, parasitic
e. Empyema (epidural, subdural, intraventricular)
3. Hemorrhagic-ischemic
f. Resolving infarction
g. Aging hematoma
h. Operative bed following resection
i. Thrombosed aneurysm
4. Demyelinating Disorder
j. Radiation necrosis
k. Necrotizing leukoencephalopathy after MTX

Front 47

Ring-Enhancing Lesion Crossing Corpus Callosum

Back 47

GAL
1. Glioma
2. Astroctyoma
3. Lymphoma
4. GAL
1. Glioma
2. Astroctyoma
3. Lymphoma
4.

Front 48

Dense and Enhancing Lesions – DDx

Back 48

1. Aneurysm
2. Meningioma
3. Lymphoma
4. Medulloblastoma
5. Mets

Front 49

Multifocal enhancing Lesions

Back 49

1. Multiple infarcts
2. Mets
3. Lymphoma
4. Multifocal GBM
5. MS/ADEM
6. Septic emboli
7. AVMs

Front 50

Innumerable Small Enhancing Cerebral Nodules

Back 50

1. Mets
2. Primary CNS lymphoma
3. Disseminated infection
a. Cysticercosis
b. Histoplasmosis
c. Tb
4. Inflammation
d. Sarcoidosis
e. MS
5. Subacute Multifocal Infarction
f. Hypoperfusion, mulitiple emboli, cerebral vasculaitis (SLE), meningitis, cortical vein thrombosis

Front 51

Periventricular T2-bright Lesion – Young Pt

Back 51

1. MS
2. Migraine
3. Vasculitic-disorder (SLE, Behcets, SCD)
4. ADEM (post-viral leukoencephalopathy)
5. VR space
6. Leukodystrophy – symmetric diffuse confluent involvement
7. Ependymitis granularis

Front 52

Periventricular T2-bright Lesions – Elderly

Back 52

1. Etate Crible (sieve-like)/gliosis
2. Lacunar infarcts

Front 53

What is the triad of a CNS vasculitis disorder

Back 53

1. Cortical infarcts
2. deep WM lesions
3. hemorrhage

Front 54

Periventricular T2-bright Lesions in PTs with AIDS

Back 54

1. Toxoplasmosis
2. HIV encephalitis – dirty white matter (well defined patchy)
3. Lymphoma
4. PML

Front 55

Periventricular T2-bright Lesions in Pts with Trauma

Back 55

1. DAI
2. Diffuse necrotizing leukoencephalopathy (intrathecal MTX + whole brain RTX

Front 56

Acute Bilateral BG Lesions – Peds

Back 56

1. Vascular compromise
a. Hemolytic-uremic syndrome (microthrombosis of BD, thalami, hippocampi, cortex)
b. Encephalitis (viral)
2. Nutrient Compromise
c. Hypoxia: respiratory arrest, near drowning, strangling, barbituate intoxication
d. Hypoglycemia – hemorrhage rare
e. Osmotic myelinolysis
3. Acute poisoning
f. CO – globus pallidus
g. Hydrogen Sulfide
h. Cyanide
i. Methanol

Front 57

Chronic Bilateral BG Lesions – Peds

Back 57

1. Inborn errors of Metabolism
a. Leigh Disease (SANEM – subacute necrotizing encephalomyelopathy), get lactic acidosis, putamenal involvement)
b. Wilson Disease – hepatolenticular degeneration – lenticular nucleus=
c. Mitochondrial encephalomyelopathies
i. Lactic academia 2º to abnormal mitochondria, RRF on bx
d. Maple syrup urine disease (leu, iso val, inability to catabolize branched-chain amino acids)
2. Degenerative Disease
e. Huntington’s disease
f. Dystrophic calcifications
3. Dysmyelinating disease (BG are part WM)
g. Canavan Disease
h. Metachromatic Leukodystrophy
4. NF – NF spots

Front 58

Low-attenuation Lesion in BG

Back 58

1. Poisoning: CO, Barbiturates, hydrogen sulfide, cyanide, methanol
2. Hypoxemia
3. Hypoglycemia
4. Hypertension (lacunar infarcts)
5. Wilson idsease

Front 59

BG Calcification

Back 59

1. Physiologic with aging
2. Endocrine
a. HypoPTH, pseudohypoPTH,
b. Hypoerparathyroidism
c. Hypothyroidism
3. Metabolic
d. Leigh disease
e. Mitochondrial cytopathy
f. Fahr disease – familial cerebrovascular ferrocalcinosis
4. Congenital/Developmental
g. Familial idiopathic symmetric BG calcification, Hastings-James syndrome, Cockayne syndrome, Lipoid proteinosis (hyalinosis cutis), NF, TS, Oculocraniosomatic disease, Methemoglobinopathy, Down Syndrome
5. Inflammation
h. Toxoplasmosis, congenital rubella, CMV
i. Measles, chicken pox
j. Pertussis, coxsackie B virus
k. Cystercircosis
l. SLE
m. AIDS
6. Trauma
n. Childhood leukemia following MTX Tx
o. RTX
p. Birth anoxia, hypoxia
q. Cardiovascular event
7. Toxic
r. CO poisoning
s. Lead intoxication
t. Nephrotic syndrome

Front 60

Basal Ganglia Calcifications

Back 60

BIRTH
1. Birth Anoxia
2. Idiopathic (most common), Infarct
3. RTx
4. Toxoplasmosis, CMV
5. hypoparathyroidism/pseudoHPT

Front 61

Linear echogenic foci in thalamus and BG

Back 61

1. in utero infection
a. TORCH
b. Syphilis
c. HIV
2. Chromosomal abnormality
d. DOWN
e. Trisomy 13
3. Others (anoxic injury)
f. Perinatal asphyxia, RDS, cyanotic congenital heart disease, necrotizing enterocolitis
g. Fetal Alcohol syndrome
h. Nonimmune hydrops

Front 62

Classification of CNS anomalies
1. Dorsal Induction Anomalies
2. Ventral Induction Anomalies
3. Neuronal Proliferation & Histogenesis
4. Neuronal Migration anomaly
5. Destructive Lesions

Back 62

1. Defects of Neural Tube Closure: Chiari malformation, encephalocele, anencephaly, spinal dysraphism, hydromyelia
2. holoprosencephaly, SOD, Dandy-Walker malformation , agenesis of septum pellucidum
3. NF, TS, primary hydranencephaly, neoplasia, vascular malformation
4. Due to infection, ischemia, metabolic disorders: schizencephaly, agyria, pachygyria, gray matter heterotopia, dysgenesis of corpus callosum, lissencephaly, polymicrogyria, unilateral megalencephaly
5. Hydranencephaly, porencephaly, hypoxia, toxicoses, inflammaty disease (TORCH)

Front 63

Absence of septum pellucidum

Back 63

1. Septo-optic dysplasia
2. Holoprosencephaly
3. callosal agenesis
4. schizencephaly
5. severe chronic hydrocephalus
6. destructive porencephaly

Front 64

Phakomatoses

Back 64

1. NF
2. TS
3. Sturge-Weber
4. VHL
5. Ataxia-telangiectasia

Front 65

Demyelinating Disease (normal myelin destroyed by disease)

Back 65

1. MS
2. Alzheimer Disease
3. Parkinson disease
4. CJD
5. Menkes disease (sexlinked recessive disorder of copper metabolism)
6. PML
7. Disseminated Necrotizing Leukoencephalopathy
8. Globoid Cell Leukodystrophy
9. Spongiform degeneration

Front 66

Dysmyelinating Disease

Back 66

1. Macrocephalic
a. Alexander disease (frontal first)
b. Canavan Disease (white matter diffusely affected)
2. Hyperdense thalami, caudate, corona radiata – Krabbe disease
3. family hx (x-linked recessive)
c. XLA
d. Pelizaeus-Merzbacher disease
4. Others
e. Metachromatic LD – most common hereditary leukodystrophy
f. Binswanger disease
g. Multi-infarct dementia
h. Pick disease
i. Huntington disease
j. Wilson Disease
k. Reye Syndrome
l. Mineralizing microangopathy
m. Diffuse sclerosis

Front 67

Hypertensive Sequelae

Back 67

1. Hypertensive encephalopathy
2. Hypertensive hemorrhage
3. Lacunar infarcts
4. SVID

Front 68

Causes of Immunocompromise

Back 68

1. AIDS
2. Malignancy
3. Cancer Therapy
4. Transplant/Inflammatory disease Immunosuppressive treatment
5. Collagen Vascular Disease

Front 69

AIDS-related pathologies

Back 69

1. Lymphoma
2. thrombocytopenia
3. plasmacytoma
4. Kaposi’s Sarcoma
5. PML

Front 70

Prolactin Elevation
1. Normal = __
2. Causes

Back 70

1. up to 25 ng/ml
2. Interference with hypothalamic-pituitary axis
a. Hypothalamic tumor
b. Parasellar tumor
c. Pituitary adenoma
d. Sarcoidosis
e. Histiocytosis
f. Traumatic infundibular transection
3. Pharmacologic agents
g. Alpha-methyldopa, reserpine, phenothiazine, tricyclics, ocp’s
4. Hypothyroidism (TRH also stimulates prolactin)
5. Renal Failure
6. Cirrhosis
7. Stress/recent surgery
8. Breast examination
9. Pregnancy
10. Lactation

Front 71

HYDROCEPHALUS vs. ATROPHY (CT)

Back 71

1. Hydrocephalus (ventricles >> sulci)
a. Ballooned and tight frontal horns –
b. Dilated temporal horns
c. - Dilated 3rd (hourglass shape) with flow void on MR
d. - decreased mammillopontine measurement (expanded 3rd pushes mammillary bodies post./inf.
e. Dilated 4th ventricle
f. Periventricular abnormal signal/density

2. Atrophy (sulci and ventricles dilate proportionately)
g. - Large cortical sulci
h. - Less 3rd ventricular dilatation (with parallel sides NOT hourglass shape)
i. - Increased with age
COMMENT: Normal pressure hydrocephalus evaluated by nuclear cisternogram.  No migration of activity over convexities/persistent intraventricular activity ... 50% aided by shunt ("shunt responsive NPH")