Transcript neurad-neuropath-feb-2011

Case 1

History
 48-year-old woman with history of end-stage
renal disease secondary to lupus, on
hemodialysis, who presented with new acute
onset of left lower extremity weakness and
difficulty walking after dialysis.

Imaging
 MRI of the thoracic spine
○ Hyperintense signal within the spinal cord
extending from T3–T6. This could possibly
relate to vasculitis from patient’s lupus.
○ T2 hypointense/T1 iso- to hyper-intense mass
within the spinal canal of the upper thoracic
spine with associated cord displacement.
This is concerning for an epidural hematoma.
○ Bilateral pleural effusions.

Surgery
 T2 through T5 laminectomy for
the evacuation of an
intradural hematoma.
 Preoperative Diagnosis:
T3–T5 extramedullary hematoma.
 Postoperative Diagnosis:
T3–T5 subdural hematoma.
 Pathology: acute blood clot.
Review of spinal lesions

Location is key
 Intramedullary
 Extramedullary, intradural
 Extradural

Identifying the CSF containing space,
the dura and the epidural fat help to
localize the abnormality.
Case 2

History
 30-year-old previously healthy man with
three weeks of episodic right-sided
numbness and tingling along with a
complete right homonymous hemianopsia
and difficulty naming objects.

Additional history
 In 2009 intermittent tinnitus had become a loud
humming that would sometimes become so loud that
he could not understand what was said to him.
 In early 2010, was seen by an ophthalmologist, who
noted retinal vasculitis.
 In the interval between visits he underwent a
cochlear implant without a magnet in order to
facilitate continued MRI screening. The implant
improved his hearing significantly in his right ear; he
remains essentially deaf in his left ear.

Surgery
 Image-guided left occipital craniotomy for
open biopsy of enhancing left occipital lobe
lesion.

Biopsy of occipital lesion revealed nonspecific brain necrosis () and reactive
gliosis in surrounding brain. The histologic changes are compatible with an infarct.
Biopsy also revealed atypical lymphoid infiltrates around blood vessels in area of
brain necrosis. The significance of these lymphoid infiltrates is not known.
Name that Eponym?

Consisting of classic clinical triad of
 subacute encephalopathy
 visual loss secondary to branch retinal artery occlusion
 sensorineural hearing loss

Answer: Susac’s Syndrome
 Caused by microangiopathy involving the brain, cochlea,
and retina
Susac’s Syndrome

Headache, often severe and sometimes migrainous, is
an almost constant complaint
 may be the major presenting feature of the
encephalopathy
 cognitive changes, confusion, and memory and psychiatric
disturbances

MR often interpreted as "typical" for MS or ADEM

In unexplained encephalopathy, a neuroophthalmologist or retinal specialist should perform a
dilated funduscopic examination…

Susac’s Syndrome


John O. Susac, Guest Editorialist, Winter Haven, FL
http://www.ajnr.org/cgi/content/full/25/3/351
Susac’s syndrome (continued)

Clinical course is usually self-limited, variable.
 2–4 years
○ as short as 6 months or as long as 5 years
 Some patients recover with little residual disease;
others are profoundly impaired.
○ cognitive deficits
○ gait disturbance
○ hearing loss
 Vision is not usually seriously impaired.

Susac’s Syndrome


John O. Susac, Guest Editorialist, Winter Haven, FL
http://www.ajnr.org/cgi/content/full/25/3/351
Susac’s syndrome (continued)

Pathogenesis is unknown.

Difficult to evaluate the results of treatment:
 IV methylprednisolone followed by oral steroids
○ in conjunction with cyclophosphamide or
immunoglobulin
 Some respond to monotherapy with steroids,
cyclophosphamide, or immunoglobulin.

Anticoagulation has no role.

Susac’s Syndrome


John O. Susac, Guest Editorialist, Winter Haven, FL
http://www.ajnr.org/cgi/content/full/25/3/351
Case 3

History
 20-year-old woman with 2–3 year history of
complex partial seizures.
Biopsy of cortical lesion revealed a proliferation of oligodendrocyte-like cells in a
myxoid background. A neuron (arrow) appears to “float” within the myxoid matrix.
DNET (DNT)

Dysembryoplastic neuroepithelial tumor, WHO grade I

Cortical location; temporal, frontal lobe

Commonly present with complex partial seizures

Slow growing—may remodel/scallop inner table of skull

Variable enhancement

May have microcystic appearance
Case 4

History
 40-year-old woman with hypertension was
transferred from an outside hospital ED
because of cerebellar infarcts.

Surgery
 Suboccipital/posterior fossa craniectomy for excision
of left cerebellar infarct and duraplasty.
 Placement of a right frontal external ventricular drain.

Pathology
 Purkinje cells (arrow) with
eosinophilic cytoplasm and
pyknotic nuclei (red neurons)
 Widespread nuclear pyknosis
in neurons of the internal
granular layer
 Only a few inflammatory cells
 The histologic changes are
consistent with an
acute cerebellar infarct.
Cerebellar Infarction

PICA > superior cerebellar > AICA

Etiology often:
 dissection of the vertebral arteries (particularly in younger patients)
 basilar artery disease (in older patients).

Cerebellar infarcts may lead rapidly to death
 caused by compression of the brain stem
 acute obstructive hydrocephalus from compression of 4th ventricle

Herniations
 Upward cerebellar herniation (seen as effacement of quadrigeminal plate cistern)
 Downward herniation of cerebellar tonsils may also occur.

Emergency resection of involved cerebellum and/or a ventriculostomy
may be required as a life-saving measure.
Case 5

History
 20-year-old man who began to notice
significant dysequilibrium on movement,
which interfered with his playing of baseball.
He noticed that he was not able to track a
baseball while moving nor to swing a bat
and hit the ball. He had previously been very
good at this.

Surgery
 Large vestibular schwannoma with multiple large
vessels contained within it was densely adherent
along the brainstem to blood vessels.
 Facial nerve was dissected in its entirety and
stimulated at 0.1 milliamps at the completion of the
case.
 There is a small residual pancake-like tumor along
brainstem, densely adherent to several large
vessels.

Pathology
 Spindle cell tumor with
some nuclear palisading
(Verocay bodies).
 Compact Antoni type A
tissue (upper left of photo)
and loose Antoni type B
tissue (lower right of photo)
are present.
 The histologic features are
consistent with a
schwannoma.
Vestibular schwannoma

AKA, “acoustic” schwannoma
 Benign tumor arising from Schwann cells of the vestibulocochlear nerve

Large tumors
 Avidly enhancing mass, with expansion of the porus acusticus, and an "ice
cream on cone“ appearance when the mass is both within the CPA and IAC

Small tumors
 High-resolution T2 MR: small low signal “filling defect" in high signal CSF

Most common presentation is an adult with unilateral sensorineural
hearing loss

If bilateral, consider NF-2 as underlying diagnosis

Important to comment on involvement of cochlear aperture
DDx of cerebellopontine angle mass
 Vestibular schwannoma
○ Most common CPA mass
 Epidermoid cyst
○ mimic rare cystic schwannoma, no enhancement
○ FLAIR/CISS/DWI to differentiate from arachnoid cyst
 Arachnoid cyst
○ follows CSF on all MR sequences; no enhancement
 Meningioma
○ dural tail; eccentric to porus acusticus without widening it
 Facial nerve schwannoma
○ Look for labyrinthine segment "tail" to differentiate
 Metastasis
 Lymphoma
 Aneurysm