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Differential Diagnosis of Nervous System Disorders

Periventricular Calcifications in Childhood!!navigator!!

  1. Tuberous sclerosis
  2. Congenital infection: CMV, toxoplasmosis

Periventricular Hypodensity!!navigator!!

  1. Encephalomalacia
    • slightly denser than CSF
  2. Porencephaly
    = cavity communicating with ventricle / cistern from intracerebral hemorrhage
    Associated with: dilated ventricle, sulci, fissures
    • CSF density
  3. Resolving hematoma
    • history of previously demonstrated hematoma
    • may show ring enhancement + compression of adjacent structures
  4. Cystic tumor
    • mass effect + contrast enhancement

Periventricular T2-hyperintense Lesions!!navigator!!

Leukoencephalopathy = disease of white matter

Leukodystrophy = degenerative diffuse sclerosis with symmetrical bilateral white matter lesions

Histo: reduced myelin, axonal loss, astrocytic gliosis

Associated with: dementia, gait abnormalities, late-onset depression

  1. NORMAL (increasing with age)
    Frequency: 22% between 0 and 20 years; 22% between 21 and 40 years; 51% between 41 and 60 years; 92% over 60 years
    1. Enlarged perivascular spaces
    2. Ependymitis granularis
    3. Neuroepithelial cyst
  2. DEMYELINATING DISEASE
    1. Multiple sclerosis
    2. Acute disseminated encephalomyelitis (ADEM) = postviral leukoencephalopathy
    3. Progressive multifocal leukoencephalopathy
    4. Lymphomatoid granulomatosis
  3. VASCULAR DISEASE
    1. Arteriolosclerosis
    2. Lacunar infarcts
    3. Migraine: in 41% with classic migraine, in 57% with complicated migraine; presumed to represent vasculitis-induced small infarcts
    4. Vasculitis: Primary angiitis of CNS (PACNS), polyarteritis nodosa, Wegener granulomatosis, SLE, Behçet disease, syphilis, Sjögren syndrome, sickle cell disease
    5. Sarcoidosis
    6. Antiphospholipid antibodies (non-SLE)
    7. Susac syndrome
    8. Periventricular leukoencephalopathy / leukomalacia (= white matter injury of prematurity)
    9. Posterior reversible leukoencephalopathy syndrome (PRES) = hypertensive encephalopathy
  4. INFECTION / INFLAMMATION
    1. HIV encephalitis:
      • well-defined “patchy” / ill-defined “dirty white matter”
      • central atrophy
    2. Lyme encephalopathy
    3. Neurocysticercosis
    4. Fungal disease: cryptococcosis
    5. Congenital CMV infection of CNS
  5. TUMOR
    1. Subependymal tumor
    2. Multiple parenchymal metastases
    3. Intravascular (angiocentric) lymphoma
  6. TRAUMA
    1. Diffuse axonal / shearing injury
    2. Diffuse white matter injury = radiation-induced (mineralizing microangiopathy)
    3. Diffuse necrotizing leukoencephalopathy = intrathecal methotrexate ± whole brain irradiation
  7. METABOLIC
    1. Vitamin B12 deficiency
    2. Hydrocephalus = transependymal CSF flow
    3. smooth halo of even thickness
    4. Pseudotumor cerebri
    5. Mucopolysaccharidosis
  8. GENETIC
    1. Neurofibromatosis 1
    2. CADASIL (= cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy)
    3. Fabry disease
    4. Globoid cell leukodystrophy = Krabbe disease
    5. Metachromatic leukodystrophy
    6. Spongiform leukoencephalopathy
    7. Adrenoleukodystrophy
    8. Fibrinoid leukodystrophy = Alexander disease

Multifocal Black Dots on T2 + T2* GRE!!navigator!!

= “blooming” susceptibility artifacts on T2* GRE

  1. Cerebral amyloid disease
  2. Hypertensive microhemorrhages
  3. Hemorrhagic lacunar infarcts
  4. Multiple vascular malformations (capillary telangiectasia, cavernous malformation)
  5. Traumatic diffuse axonal injury
  6. Embolic microhemorrhages:
    1. Hemorrhagic micrometastases
    2. Metallic microemboli from artificial heart valves
    3. Microhemorrhages from fat emboli
  7. CADASIL (= cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy)

Corpus Callosum Lesion!!navigator!!

  1. TUMOR
    1. GBM
    2. Lymphoma
    3. Metastasis
  2. TRAUMA
    1. Shearing injury
  3. WHITE MATTER DISEASE
    1. Multiple sclerosis
    2. Progressive multifocal leukoencephalopathy
    3. Adrenoleukodystrophy
    4. Marchiafava-Bignami disease (often related to chronic alcoholism)
  4. INFECTION
    1. Toxoplasmosis

Ring-enhancing Lesion Crossing Corpus Callosum

mnemonic: GAL

  • Glioblastoma multiforme (butterfly glioma)
  • Astrocytoma
  • Lymphoma

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