December 2010
Clinical Neuroradiology–
Neuropathology Conference
Patrick Farley, MD (Neuroradiology Fellow) and
Thomas Bouldin, MD (Neuropathologist)
Case #1
CLINICAL HISTORY: 59-year-old man with history
of altered mental status and hearing loss.
Differential diagnosis

Infectious Meningitis

Neoplastic Meningitis


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Breast, lung most common extracranial sources
Most common primary brain tumors are GBM, medulloblastoma,
pineal tumors, and choroid plexus tumors
Neurosarcoidosis
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Lacy leptomeningeal enhancement
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May have ventricular or dural-based enhancing masses
Brain biopsy revealed a poorly differentiated neoplasm within the leptomeninges and
around several intracortical blood vessels. The immunophenotype of the neoplastic cells
was consistent with a melanoma. The histologic features do not permit distinction between
metastatic melanoma (common) and primary leptomeningeal melanoma (rare).
Case #2
CLINICAL HISTORY: 21-year-old postpartum
woman with a sellar mass.
Differential Diagnosis

Adenoma
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Pituitary hyperplasia
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25–50% of females 18–35 years old have upwardly convex pituitary
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Usually < 10 mm unless pregnant, lactating
Aneurysm
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Usually eccentric, not directly suprasellar
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Pituitary gland visible and identified as separate from mass
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Flow-related artifacts on MRI are common
Meningioma
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Pituitary gland may be visible and identified as SEPARATE from mass
Differential Diagnosis (continued)
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Metastasis
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Lymphocytic hypophysitis
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Can mimic adenoma clinically and on imaging studies
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May show zones of very low T2 signal peripherally
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Most common in peripartum female
Craniopharyngioma
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Ca++, cysts more common, Children > adults
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Rim/nodular > solid enhancement
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May be indistinguishable from Rathke cleft cyst
Biopsy revealed a dense lymphoplasmacytic infiltrate within the anterior pituitary. The
gland also showed interstitial fibrosis and a loss of secretory cells. The remaining
secretory cells form the clusters of larger, more eosinophilic cells in the photomicrograph.
Lymphocytic hypophysitis
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Females > males, with a ratio of approximately 5:1
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Often during last months of pregnancy or first few months postpartum

Often have family history of autoimmune disease
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Sometimes associated with Hashimoto’s thyroiditis or Graves’ disease
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No adverse effect on fetus

Presents as hypopituitarism and/or mass effect—headache or visual field cuts

If unrecognized, may cause death from panhypopituitarism
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Treatment includes hormonal replacement and surgery to reduce mass effect.
Lymphocytic hypophysitis


Diagnostic signs:
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Thick non-tapered stalk, with or without pituitary mass

Supra, intrasellar mass

Areas of low T2 signal peripherally or/and in cavernous sinuses

Usually < 10 mm but may be up to 2-3 cm
Rounded pituitary gland with infundibulum that appears thickened,
nontapering, or bulbous
CASE #3
CLINICAL HISTORY: 73-year-old female with
acute headache and right-sided weakness.
Differential Diagnosis

Hypertensive hemorrhage

Deep structures (basal ganglia, thalami, cerebellum) but may also occur in
cortex and subcortical white matter
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Hemorrhagic infarct
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Hemorrhagic metastases
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Cerebral amyloid angiopathy
Beta Amyloid IHC
Postmortem examination of the brain in this case revealed numerous cortical and
leptomeningeal vessels infiltrated by amorphous, eosinophilic amyloid. Inset shows the
immunohistochemical staining of the amorphous material for beta amyloid.
Cerebral amyloid angiopathy (CAA)
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Deposition of beta amyloid in cortical and leptomeningeal vessels

Common in older patients

Often associated with Alzheimer’s disease

Complications of CAA include intracerebral lobar hemorrhage, microbleeds,
subarachnoid hemorrhage, cerebral infarcts, inflammatory CAA, and whitematter abnormalities.
CAA Imaging

Look for:


Lobar hemorrhage(s) of different ages
Multifocal areas of susceptibility artifacts corresponding to chronic
microbleeds, particularly in cortex
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Hemorrhage may extend to subarachnoid space or into ventricles
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Acute lobar hemorrhage tends to be large
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Protocol advice:

Recommend T2*-weighted sequence in all patients > 60 years of age
Case #4
CLINICAL HISTORY: 65-year-old man with
history of renal cell carcinoma first diagnosed
in 1994. He has since had numerous surgeries
for metastases to the brain. He also had
stereotactic radiosurgery for an olfactory
groove-based lesion, which was presumed to
be a meningioma.
Case #4
CLINICAL HISTORY (continued): A few months
later the presumed meningioma developed
surrounding edema, became larger, and
demonstrated areas of different enhancement
intensity and T2 signal.
Biopsy of the olfactory-groove lesion revealed a meningioma (right half of
photomicrograph). Also present within the meningioma was a focus of metastatic renal
cell carcinoma (left half of photomicrograph).
Tumor-to-tumor metastasis
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
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Metastasis of a systemic cancer to an intracranial tumor is rare.
Most often, the CNS tumor is a meningioma. Other reported types of
intracranial tumors harboring a metastasis include 8th-nerve schwannoma,
glioma, hemangioblastoma, and pituitary adenoma.
Breast and lung are the most common primary sites, with breast being the
most common site.
Renal cell carcinoma metastatic to a meningioma has been reported only
rarely. Renal cell carcinoma may also metastasize to a hemangioblastoma in
the context of the von Hippel-Lindau syndrome.
Lanotte M, et al. Systemic cancer metastasis in a meningioma: Report
of two cases and review of the literature. Clinical Neurology and
Neurosurgery 111 (2009) 87–93.
Case #5
CLINICAL HISTORY: 2-year-old AfricanAmerican girl with left eye strabismus for 9
months.
Differential Diagnosis

Retinoblastoma

Calcifications, enhancement, mass of low T2 signal intensity

Persistent hyperplastic primary vitreous
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Coat’s disease
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Retinal astrocytoma
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
Rare; isolated or in association with tuberous sclerosis (TSC)
Ocular toxocariasis
PHPV
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Congenital


Imaging


Due to incomplete regression of embryonic ocular blood supply
Best diagnostic clue: Hyperdense or hyperintense small globe, retrolental
soft tissue, no Ca++

Retinal detachment common

Central linear structure: Cloquet’s canal

Layering blood or debris may be present
PHPV is the most common intraocular abnormality to be confused with
retinoblastoma
The intraocular lesion is a small blue cell tumor with neuroblastic (Homer Wright) rosettes
(arrows). The histological features of the tumor are typical of a retinoblastoma.
Retinoblastoma
CT:

Calcified intraocular mass

Unilateral in 70-75%
MR:

T2 Hypointense relative to vitreous

Moderate to marked heterogeneous enhancement

Best for assessing extraocular and intracranial disease