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100 BIOMEDICAL FACTOIDS
This page contains 100 factoids from the field of
biomedicine. There are about 180 additional pages in this
series.
This page has no value as a treatment guide or as a diagnostic
guide. It is merely a collection of interesting pieces of
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© 2007 Jules J. Berman
301
GENDER INCIDENCE OF BRAIN CANCER.
Males are twice as likely as females to have intracranial gliomas
(this generalization even extends to the incidence of cerebellar
astrocytomas and medulloblastomas of children).
Intracranial schwannomas are more frequent in females, and females
are twice as likely to develop intracranial meningiomas as males.
Spinal meningiomas involve females with 4 times the frequency of males.
Interestingly, nonclinical small meningiomas found incidentally
at autopsy, seem to have no sex predilection.
--------------------
Rubinstein LJ. Tumors of the nervous system. Armed Forces Institute
of Pathology, Washington, D.C. p. 3, 1972.
key words: brain, CNS, epidemiology, JB
302
INCIDENCE OF BRAIN TUMORS.
"Primary tumors of the central nervous system and its coverings account
for about 1.2% of all autopsied deaths and for approximately 9%
of all primary neoplasms."
--------------------
Rubinstein LJ. Tumors of the nervous system. Armed Forces Institute
of Pathology, Washington, D.C. p. 1, 1972.
key words: brain, CNS, epidemiology, JB
303
AREAS OF THE BRAIN THAT LACK A BLOOD-BRAIN BARRIER.
Choroid plexus.
Area postrema.
Infundibulum.
Pineal body.
key words: brain, cns, histology, JB
304
GEMISTOCYTE.
A swollen astrocyte with granular cytoplasm and an eccentric nucleus.
A variant of astrocytoma (gemistocytic astrocytoma) contains such cells.
key words: brain, cns, histology, JB
305
HYPOXIC BRAIN LESIONS OF THE NEWBORN.
Matrix zone intraventricular hemorrhages.
Cerebellar, subpial, and subarachnoid hemorrhages.
Periventricular leukomalacia.
White matter gliosis.
Brain stem necrosis (3 types are ponto-subicular necrosis,
hypotensive brain stem necrosis and Mobius syndrome).
Status marmoratus (thalamus and deep grey matter injury).
Infarction.
key words: brain, CNS, ischemia, pediatric neonatal, JB
306
LESIONS OF THE INTERNAL CAPSULE.
Look for the 3 H's:
Hemiplegia.
Hemianesthesia.
Homonymous hemianopsia.
key words: brain, cns, JB
307
NORMAL PRESSURE HYDROCEPHALUS.
Also known as Hakim's syndrome.
Clinically, look for:
Dementia.
Incontinence.
Gait apraxia.
key words: brain, cns, JB
308
SUBEPENDYMOMA.
Also called subependymal astrocytoma and subependymal glomerate astrocytoma.
Most are found incidentally at autopsy as small polyps
from the wall of the fourth ventricle.
On histology, look for small nests of small blue cells in a dense matrix
of eosinophlic fibrillar material.
key words: brain, CNS, JB
309
SUBEPENDYMAL GIANT CELL ASTROCYTOMA.
Needs to be distinguished from subependymoma.
This tumor is most often seen as part of tuberous sclerosis,
but may occur sporadically.
Arises from the wall of the lateral ventricle.
Presents as an intraventricular mass.
Can obstruct the foramen of Monro.
May produce hydrocephalus.
The tumor may have a variety of histologic morphologic features.
These are slowly growing neoplasms that are most often composed
of very large cells with abundant hyaline, eosinophlic cytoplasm.
--------------------
Rubinstein LJ. Tumors of the nervous system. Armed Forces Institute
of Pathology, Washington, D.C. pp. 40-41, 1972.
key words: brain, CNS , JB
310
ACOUSTIC SCHWANNOMA TERMINOLOGY.
The terms acoustic neuroma and acoustic neurofibroma and acoustic schwannoma
and acoustic neurinoma are used synonymously for the tumor that envelops
the axons of the peripheral nerve (8th cranial nerve) root,
as it leaves the CNS.
key words: brain, CNS, JB
311
NEUROFIBROMAS OF SPINAL CORD VERSUS SCHWANNOMAS OF SPINAL CORD.
Neurofibromas, like schwannomas, are composed principally
of neoplastic Schwann cells.
However, the two tumors are usually morphologically and clinically distinct.
Neurofibromas arising from spinal nerve roots tend to occur as areas
of increased thickness of the nerve, often growing as dumbbell-shaped
lumps flanking the intervertebral foramina.
Microscopically, they are loose textured, without Antoni type A areas.
Unlike schwannomas, neurofibromas may undergo malignant change.
Schwannomas grow as well-demarcated, encapsulated and typically
round masses attached to the nerve roots.
key words: brain, CNS, JB
312
HEMANGIOBLASTOMAS.
Account for 1 to 2.5% of intracranial tumors.
The most common site of occurrence is the cerebellum.
The average age of onset of symptoms from this tumor is 33.
--------------------
Rubinstein LJ. Tumors of the nervous system. Armed Forces Institute
of Pathology, Washington, D.C. p. 235, 1972.
key words: brain, CNS, JB
313
CHRONIC PREGANGLIONIC AUTONOMIC INSUFFICIENCY.
Seen in 3 disorders:
Shy-Drager syndrome.
Progressive cerebellar degeneration.
Striato-nigral degeneration.
key words: brain, cns, JB
314
BRAIN HERNIATIONS.
Cingulate gyrus (under the falx).
Uncal (herniation of the parahippocampal gyrus).
Central, a transtentorial herniation from the supratentorial area
to the posterior fossa area through the tentorial hiatus).
Cerebellar (tonsillar) herniation from the posterior fossa
through the foramen magnum into the spinal canal.
Transcalvarial (through an opening in the skull).
key words: brain, cns, JB
315
RATHKE CLEFT CYST
Usually encountered only as an incidental finding at autopsy.
May become a clinical problem when large (> 1 cm), causing visual disturbances
or causing hypothalamic or pituitary dysfunction.
Often lined by tall columnar epithelium that may be ciliated.
These cells can help in the cytologic diagnosis of aspirated cyst fluid.
--------------------
Burger PC, Scheithauer BW. Atlas of Tumor Pathology (Third Series,
Fascicle 10) Tumors of the Central Nervous System. Armed Forces Institute
of Pathology, Washington, D.C., p. 358, 1994.
key words: brain, cns, JB
316
EOSINOPHILIC GRANULAR BODIES.
Seen in cells of 3 brain tumors:
Pleomorphic xanthoastrocytoma.
Pilocytic astrocytoma.
Ganglion cell tumors.
key words: brain, cns, JB
317
REFSUM'S SYNDROME.
Phytanic acid storage disease (phytanic acid stored in tissues and blood).
Clinically, look for:
Peripheral neuropathy.
Ataxia.
Retinitis pigmentosa.
key words: brain, CNS, metabolic, JB
318
STRIATONIGRAL DEGENERATION.
Rare.
Symptoms similar to Parkinson's disease.
Corpus striatum (putamen and caudate) suffers cell loss and gliosis.
Some of these patients also have Shy-Drager syndrome
or have olivo-pontocerebellar atrophy.
key words: brain, CNS, neurology, JB
319
PATHOLOGY OF PROGRESSIVE SUPRANUCLEAR PALSY.
Neuronal loss and gliosis of:
Dentate nucleus.
Globus pallidus.
Periaquaductal gray matter.
Red nucleus.
Substantia nigra.
Subthalamic nucleus.
Tectum.
key words: brain, cns, neurology, JB
320
WERDNIG-HOFFMAN DISEASE.
Also called infantile spinal muscular atrophy.
Clinically characterized:
Infantile onset of progressive weakness and atrophy.
Absent deep tendon reflexes.
Tongue fasciculations.
Ocular muscles are not involved.
There is degeneration of lower motor neurons.
Death usually occurs in the first year of life,
but the later the onset of the disease, the longer the survival.
Late-onset Werdnig-Hoffman is difficult to distinguish
from Kugelberg-Welander syndrome.
key words: brain, cns, neurology, JB
321
PATHOLOGY OF WERDNIG-HOFFMAN DISEASE.
denervation atrophy of skeletal muscle all over the body
with some sparing of the diaphragm and neck muscles.
key words: brain, cns, neurology, JB
322
KUGELBERG-WELANDER SYNDROME.
Can be thought of as a late onset Werdnig-Hoffman disease.
The later the onset, the better the prognosis,
and some patients attain a normal life span.
key words: brain, cns, neurology, JB
323
PLEOMORPHIC XANTHOASTROCYTOMA.
Rare.
Seen in children and young adults.
Involves meninges and cerebral cortex (temporal lobe).
In differential diagnosis:
Desmoplastic cerebral astrocytoma of infancy.
Desmoplastic infantile gangliogliomas.
Fibrosarcoma.
High grade glioma.
Intracranial localized MFH.
Meningioma.
key words: brain, cns, pediatric, astrocytoma, JB
324
GLIOMATOSIS CEREBRI.
Seen most often in patients between 10 and 30.
There is widespread glial tumor involving cerebrum, cerebellum and brainstem.
Tumor spreads along the molecular layer and beneath the ependyma.
--------------------
Rubinstein LJ. Tumors of the nervous system. Armed Forces Institute
of Pathology, Washington, D.C. pp. 12-28, 1972.
key words: brain, CNS, pediatric, childhood, JB
325
INCIDENCE OF INTRACRANIAL GLIOMAS IN CHILDREN.
Astrocytomas ................... 48%.
Medulloblastomas ............... 44%.
Ependymomas .................... 8%.
--------------------
Rubinstein LJ. Tumors of the nervous system. Armed Forces Institute
of Pathology, Washington, D.C. p. 2, 1972.
key words: brain, CNS, pediatric, epidemiology, JB
326
STATUS MARMORATUS.
Translated, means a marbled state.
Pattern of thalamus and deep grey matter injury resulting from in utero
or perinatal hypoxia.
The marbled state occurs when surviving neurons become myelinated
in a haphazard fashion (however, the common situation is that there
are not enough surviving nuclei for myelinization to occur).
A curious clinical consequence of thalamic injury in the neonate
is that the infant loses the ability to suck (due to loss
of thalamic pathway of lip sensation).
key words: brain, CNS, pediatric, ischemia, JB
327
JACKSONIAN SEIZURE.
A seizure that spreads down the motor cortex.
Begins with twitching of a group of muscles,
and progresses episodically ipsilaterally.
Consciousness is usually retained.
Usually secondary to focal motor cortex lesion.
key words: brain, cns, seizure, clinical, JB
328
INCIDENCE OF CRANIOPHARYNGIOMA.
Craniopharyngioma accounts for 3% of all intracranial tumors.
More than half are seen in the first and second decades.
When they compress the optic chiasm, they produce hemianopsia.
--------------------
Rubinstein LJ. Tumors of the nervous system. Armed Forces Institute
of Pathology, Washington, D.C. p. 292, 1972.
key words: brain, CNS, sella turcica, ameloblastoma, adamantinoma, JB
329
CLINICAL SIGNS OF CEREBELLAR HEMORRHAGE.
Repeated vomiting.
Almost never associated with loss of consciousness.
In the acute phase, there are surprisingly few localizing
signs of cerebellar disease.
key words: brain, cns, stroke, JB
330
VERTEBRAL-BASILAR ARTERY SYNDROMES.
Include:
Visual disorders due to lack of perfusion of the occipital lobes.
Brain-stem disorders (basilar arteries).
Sometimes cerebellar disorders.
key words: brain, cns, stroke, JB
331
BRAIN INFARCTS.
Infarcts in the brain are not surrounded by a wall.
Old infarcts are typically simple cavities.
Abscesses are surrounded by a wall.
The progression of gross morphologic events in brain infarcts usually is:
No morphologic change in the first 6 hours.
Then blurring of grey-white margin.
Then small hemorrhages.
Softening after 48 hours.
Cystic degeneration after 10 days.
key words: brain, cns, stroke, JB
332
MILD SPONTANEOUS SUBARACHNOID HEMORRHAGE.
A frequently missed diagnosis.
Failure to make the diagnosis can be disastrous for the patient.
Usually due to a burst cerebral aneurysm.
Look for: a severe headache that occurs essentially instantaneously.
May occur in the absence of any other neurologic findings.
Diagnosis can often be made on CT scan and, in the absence
of a positive CT scan, can often be made by lumbar puncture.
Any headache that is severe and that occurs rapidly should be considered
a subarachnoid hemorrhage until tests exclude this diagnosis
(CT scan and lumbar puncture).
key words: brain, cns, stroke, JB
333
THE MIDDLE CEREBRAL ARTERY AND APHASIA.
The middle cerebral artery feeds virtually all the areas
of the brain concerned with speech.
So when a speech disorder has a vascular origin, it is almost
certainly due to a lesion in the middle cerebral artery or its branches.
key words: brain, cns, stroke, JB
334
VIRCHOW-ROBIN SPACES.
Perivascular spaces in the brain.
key words: brain, cns, terminology, JB
335
MENINGIOMAS
Angioblastic meningioma, Angiomatous meningioma
Diffuse meningiomatosis, Endotheliomatous meningioma
Fibroblastic meningioma, Fibrous meningioma
Hemangioblastic meningioma, Hemangiopericytic meningioma
Leptomeningeal sarcoma, Meningeal sarcoma
Meningeal sarcomatosis, Meningioma, Meningioma malignant
Meningiomatosis, Meningothelial sarcoma
Meningotheliomatous meningioma, Mixed meningioma
Multiple meningiomas, Papillary meningioma
Psammoma, Psammomatous meningioma
Syncytial meningioma, Transitional meningioma
key words: brain, cns, terminology, JB
336
SUBEPENDYMOMA.
Definition: ``A highly differentiated, slow-growing glioma,
composed of ependymal and astrocyte-like cells, arising in the walls
of the ventricular system or, rarely, the parenchyma of the spinal cord.''
--------------------
Burger PC, Scheithauer BW. Atlas of Tumor Pathology (Third Series,
Fascicle 10) Tumors of the Central Nervous System. Armed Forces Institute
Pathology, Washington, D.C., p. 133, 1994
key words: brain, cns, tumor, neuropathology, JB
337
CHOROID PLEXUS TUMORS.
Choroid plexus papilloma and carcinoma occur in the ventricles,
except for some 4th ventricle tumors, that traverse
the foramen of Luschka and form a mass in the cerebellopontine angle.
--------------------
Burger PC, Scheithauer BW. Atlas of Tumor Pathology (Third Series,
Fascicle 10) Tumors of the Central Nervous System. Armed Forces Institute
of Pathology, Washington, D.C., p. 136, 1994.
key words: brain, cns, tumor, neuropathology, JB
338
CENTRAL NEUROCYTOMA.
An intraventricular tumor of small, mitotocially inactive cells.
Also known as:
Central neuroblastoma.
Differentiated neuroblastoma.
Can occur at any age, but most occur in young adults.
Often calcified.
Perinuclear halos may confuse morphology with that of oligodendrogliomas.
Ependymomas may also be confused with neurocytomas.
``Most ependymoma, however, intrude unilaterally into a ventricle,
and also involve paraventricular tissue, whereas neurocytomas lie
in the midline involving the septum pellucidum,
and are exclusively intraventricular.''
--------------------
Burger PC, Scheithauer BW. Atlas of Tumor Pathology (Third Series,
Fascicle 10) Tumors of the Central Nervous System. Armed Forces Institute
of Pathology, Washington, D.C., p. 133, 1994
key words: brain, cns, tumor, neuropathology, JB
339
CNS HEMANGIOPERICYTOMAS ARE NOT A TYPE OF MENINGIOMA.
According to the authors of the AFIP CNS tumor fascicle, hemangiopericytomas
are not a morphologic variant of meningioma. Rather, they are a distinct
neoplasm unrelated to meningioma.
Interestingly, unlike meningiomas, they have no sex predilection
(meningiomas preferentially occur in women).
Hyperostosis of the bone (in bone invading meningiomas) is not seen
with bone-invading hemangiopericytomas.
--------------------
Burger PC, Scheithauer BW. Atlas of Tumor Pathology (Third Series,
Fascicle 10) Tumors of the Central Nervous System. Armed Forces Institute
of Pathology, Washington, D.C., p. 293, 1994.
key words: brain, cns, tumor, neuropathology, JB
340
SV40 IN CHOROID PLEXUS TUMORS.
SV40 virus is an oncogenic polyoma virus.
Choroid plexus tumors appear in transgenic mice carrying SV40 sequences.
DNA sequences similar to those found in SV40 have been found
in human choroid plexus tumors and ependymomas.
--------------------
Bergsagel DJ, Finegold MJ, Butel JS, Kupsky WJ, Garcea RL. DNA sequences
similar to those of simian virus 40 in ependymomas and choroid plexus tumors
of childhood. New Engl J Med 326:988-993, 1992.
key words: brain, cns, tumor, neuropathology, oncovirus, svv, JB
341
SECONDARY STRUCTURES OF SCHERER.
Consist of:
Subpial aggregates of tumor cells beneath the superficial part
of the molecular layer and beneath the ependyma.
Perivascular tumor cells in the brain parenchyma outside
the Virchow-Robin spaces or around the neurons.
TERTIARY STRUCTURES OF SCHERER.
Changes in malignant gliomas due to extensive necrosis and hemorrhage.
Characterized by:
Gliosis.
Scar formation.
Vessel proliferation.
--------------------
Rubinstein LJ. Tumors of the nervous system. Armed Forces Institute
of Pathology, Washington, D.C. pp. 12-28, 1972.
key words: brain, CNS, tumor biology, JB
342
CYSTS IN BRAIN TUMORS.
84% of craniopharyngiomas have cysts.
83% of hemangioblastomas have cysts.
77% of astrocytomas in the cerebellum have cysts.
29% of astrocytomas in the cerebral hemispheres have cysts.
39% of glioblastomas have cysts.
21% of oligodendrogliomas have cysts.
Cysts are unusual in meningiomas and rare in schwannomas.
--------------------
Hardman JM, Yang H. The central nervous system. In: Silverberg SG, ed.,
Principles and Practice of Surgical Pathology, Wiley, New York,
pp. 1579-1656, 1983.
key words: brain, CNS, tumor biology, JB
343
CALCIFICATION IN BRAIN TUMORS.
75% of craniopharyngiomas have calcifications.
70% of oligodendrogliomas have calcifications.
28% of oligodendrogliomas have calcifications.
25% of ependymomas have calcifications.
--------------------
Hardman JM, Yang H. The central nervous system. In: Silverberg SG, ed.,
Principles and Practice of Surgical Pathology, Wiley, New York,
pp. 1579-1656, 1983.
key words: brain, CNS, tumor biology, JB
344
LOCATION OF BRAIN TUMORS.
In children, about 70% of all brain tumors are infratentorial,
while in adults 70% are supratentorial.
The tentorium is the dura mater that separates the occipital lobes
from the cerebellum. The name derives from the Latin word "tent."
key words: brain, CNS, tumor biology, pediatric, JB
345
ARTERIOVENOUS MALFORMATIONS.
Also known as arteriovenous angioma.
Account for 0.5% to 3.7% of neurosurgical procedures.
Seen twice as often in males as in females.
These malformations may result in intracerebral or subarachnoid hemorrhage.
Unlike hemorrhage from a ruptured berry aneurysm, they are seldom fatal.
Large AVM's can prduce gliosis and atrophy and result in epilepsy
or paralysis or headaches.
Rarely, the AVM may lead to cardiac hypertrophy and CHF.
--------------------
Rubinstein LJ. Tumors of the nervous system. Armed Forces Institute
of Pathology, Washington, D.C. p. 246-247, 1972.
key words: brain, CNS, vascular, JB
346
CIRCLE OF WILLIS HEMORRHAGE.
The circle of Willis lies in the subarachnoid space,
so that blood from a ruptured saccular aneurysm escapes into the CSF.
If the hemorrhage of a ruptured saccular aneurysm is confined
to the subarachnoid space, there are usually no lateralizing signs.
key words: brain, cns, vascular, JB
347
STURGE-WEBER DISEASE.
Rare syndrome:
Capillary-venous malformation of one cerebral hemisphere.
Port-wine stain of face on homolateral side,
in the region of the trigeminal nerve.
Contralateral hemiparesis.
Jacksonian epilepsy.
Sometimes glaucoma on the affected side.
--------------------
Rubinstein LJ. Tumors of the nervous system. Armed Forces Institute
of Pathology, Washington, D.C. p. 255, 1972.
key words: brain, CNS, vascular, JB
348
XANTHOGRANULOMA OF THE CHOROID PLEXUS.
Frequently as incidental finding.
Yellow rubbery mass in the choroid plexus, often bilateral, measuring 1-2 cm.
Can be thought of as a degenerative cholesterol-laden focus,
within the choroid plexus (cholesterol granuloma).
--------------------
Rubinstein LJ. Tumors of the nervous system. Armed Forces Institute
of Pathology, Washington, D.C. p. 262, 1972.
key words: brain, CNS, ventricle, JB
349
HERPES ENCEPHALITIS.
Seems to particularly involve the temporal lobes.
You see a lot of RBC's in the CSF, because it is a hemorrhagic process.
key words: brain, cns, virus, microbiology, JB
350
SUBACUTE SCLEROSING PANENCEPHALITIS (SSPE).
Often fatal.
Occur months after a measles infection.
Look for:
Mental deterioraton.
Myoclonic jerks.
Seizures.
key words: brain, cns, virus, microbiology, JB
351
CREUTZFELDT-JAKOB DISEASE (SUBACUTE SPONGIFORM ENCEPHALOPATHY).
This disease was formerly called a slow virus disease.
This `slow virus' is now considered most likely to be a prion disease.
It is clinically characterized by:
Presenile dementia (in virtually all cases).
Motor disturbances.
Tremors.
Spasticity.
Amyotrophy.
The infectious agent is resistant to boiling water, formalin and alcohol,
but is inactivated by bleach.
Histologically, in brain sections, look for spongiform change
characterized by vacuoles in the neuropil.
key words: brain, cns, virus, slow, prion, JB
352
BATTLE'S SIGN.
Bogginess of the temporal or post-auricular area seen in skull fracture.
key words: brain, cranium, JB
353
WERNICKE-KORSAKOFF SYNDROME.
Combination of Wernicke's encephalopathy and Korsakoff's dementia.
In Western countries, this syndrome is seen almost exclusively
in chronic alcoholics.
It is produced by thiamine deficiency (vitamin deficit).
key words: brain, degeneration, JB
354
KORSAKOFF'S PSYCHOSIS.
Clinical condition characterized by inability to form long-term memories
For example, when a patient forgets who you are,
as soon as you leave the room.
key words: brain, degeneration, JB
355
MYELINATION.
Oligodendrocytes myelinate neuronal axons in the CNS,
and one oligodendrocyte may send processes that wrap many neurons.
Schwann cells myelinate neuronal axons in the PNS (peripheral nervous system)
and one Schwann cell myelinates only one axon.
key words: brain, development, JB
356
PORENCEPHALY.
A type of CNS malformation associated with usually severe neurologic problems
and characterized by holes in the brain (missing areas of the brain).
2 types:
1. The brain develops normally but is secondarily destroyed.
2. Schizencephaly. The brain develops with distorted growth
(no scarring and necrosis is tissues).
key words: brain, development, pediatric, JB
357
GENERAL MICROSCOPIC FINDINGS IN CNS INFECTION WITH VIRUS.
Neuronophagia.
Perivascular lymphocytic cuffing.
Microgliosis.
key words: brain, encephalitis, JB
358
CANDIDA AND MENINGITIS.
Candida can produce abscesses in the brain, but it has virtually
no chance of producing meningitis, and you should not expect
to see it in CSF fluid.
key words: brain, encephalitis, JB
359
PAPILLEDEMA.
Also called choked disk.
It is a swelling of the optic nerve head due to an increase
in intracranial pressure.
Usually bilateral.
key words: brain, eye, fundus, JB
360
CYTOGENETIC ABNORMALITY OF ACOUSTIC NEUROMA.
All cases of vestibular schwannomas (sporadic or familial) are thought
to result from the functional loss of a tumor-suppressor gene
that has been localized to the long arm of chromosome 22.
key words: brain, genetic, JB
361
HYPERTENSIVE INTRACEREBRAL HEMORRHAGE.
Results from rupture of arteries inside the brain tissue,
not from rupture of subarachnoid vessels.
Once it has occurred, rebleeding from the same site is unlikely,
whereas saccular aneurysms causing subarachnoid
have a high chance of recurrence.
Hypertensive hemorrhage almost always occurs in awake patients.
Transient ischemic attacks are not associated with hypertensive
intracerebral hemorrhage (they are associated with infarction,
a different disease process).
key words: brain, hemorrhage, stroke, vascular, cns, JB
362
COMMON SITES OF HYPERTENSIVE HEMORRHAGE.
Putamen and internal capsule.
Deep white matter of the cerebral cortex (e.g., corona radiata).
Thalamus.
Cerebellum.
Pons (in contrast, embolic infarcts rarely involve the pons).
key words: brain, hemorrhage, stroke, vascular, JB
363
CNS CHANGES IN TUBEROUS SCLEROSIS.
Localized pachygyria.
Cortical tubers.
Periventricular masses including a lesion composed of a mixture
of heterotopic brain tissue, hamartomatous overgrowth and astrocytoma;
Also a subependymal giant cell astrocytoma.
Enlarged ventricles (secondary to tumor growth or unexplained).
Ocular phakomas.
Mental deficiency (<40%) and seizures (often first sign of disease).
key words: brain, hereditary, JB
364
TSH ADENOMAS.
Thyrotrophin pituitary adenomas are rare.
Thyrotrophic cells are few in the normal pituitary.
They are normally basophilic and (like all basophilic pituitary cells)
PAS-positive.
Most of these tumors are chromophobe adenomas.
About half of these tumors are functional.
TSH cell hyperplasia (not to be confused with TSH adenoma)
sometimes occurs as a result of primary hypothyroidism.
The thyrotrophs appear as tiny islands of cells.
key words: brain, hypophysis, JB
365
NULL CELL ADENOMAS.
About one out of 5 pituitary adenomas show no clinical
or immunohistochemical evidence of hormone production.
These tumors are sometimes divided into oncocytic
and non-oncocytic types depending on the concentration
of mitochondria in their cytoplasm.
These tumors are diagnosed based on their size, so virtually
all of them are macroadenomas (greater than 1 cm).
Almost half show some extrasellar extension.
key words: brain, hypophysis, JB
366
CALCOSPHERITES IN PITUITARY PROLACTINOMAS.
Psammoma bodies occur frequently in pituitary prolactinomas.
The authors suggest that these concretions first begin
as foci of calcification arising in the area of organelle degeneration
in the neoplastic pituicytes.
--------------------
Lipper S, Isenberg HD, Kahn LBB, Calcospherites in pituitary prolactinomas:
a hypothesis for their formation. Arch Pathol Lab Med 108:31-34, 1984.
key words: brain, hypophysis, JB
367
LOCATIONS OF LEWY BODIES.
Found in Parkinson's disease in the following sites:
Dorsal motor vagal nucleus.
Intermedio-lateral cell column.
Locus ceruleus.
Numerous brainstem nuclei.
Substantia innominata.
Substantia nigra.
Sympathetic ganglia.
key words: brain, inclusion, JB
368
CEREBRAL INFARCT AND BLOODY CSF.
Cerebral infarcts, even when hemorrhagic, seldom produce blood in the CSF,
although it may result in a xanthochromic tinge to the CSF.
key words: brain, infarct, stroke, JB
369
TUBEROUS SCLEROSIS.
Hypopigmented papules (vitiligo) frequent at birth (inactive melanocytes
with abnormal melanosomes).
White streak of hair is common.
Infantile spasms, epilepsy, mental retardation common.
Nodules in the brain are usually periventricular and gliotic.
Adenoma sebaceum of face may appear (actually fibroangiomatous papules).
White, nodular retinal colobomata may be present.
Also seen:
Shagreen patches (dense collagen plaques).
Intracranial calcification.
Subungual fibroma.
Angiomyolipoma of kidney (adults).
Pseudocysts of hands and feet.
Pitted tooth enamel.
key words: brain, inherited, syndrome, CNS, JB
370
SHOCK LESIONS OF THE BRAIN.
In clinical shock, lesions of other organs, including the lungs, liver,
heart and kidneys are much more common than lesions of the brain.
The low rate of shock associated CNS pathology may be due to the effective
autoregulation of blood perfusion in the brain.
The first areas to suffer shock injury in the brain are the hippocampus,
the basal ganglia and the cerebellum.
Besides frank infarcts, the pathologists can see a lesser but distinctive
injury characterized by a loss of neurons,
without areas of obvious necrosis.
Cell populations undergoing hypoperfusion related cell drop-out
are Sommer's sector of the hippocampus and the Purkinje cells
of the cerebellum.
key words: brain, ischemia, infarct, JB
371
DO YOU HAVE A HEADACHE?
Most headaches are medically trivial, but when does a headache
need medical attention?
When it is accompanied by fever, stiff neck and chills.
When it is unresponsive to the remedies that usually work.
When the temporal artery(ies) are tender.
When you have blurred vision or slurred speech or numbness or memory loss.
When it wakes you up from your sleep.
When there is a new pattern headache with onset in middle age.
When there is a change in your usual headache pattern.
When it gets worse when you stand up.
--------------------
Malakoff G. When should you worry about your headache? Could it be
a migraine-or something worse? The George Washington University Personal
Health Letter 1:1-3, 1991.
key words: brain, JB
372
WERNICKE ENCEPHALOPATHY.
Clinically:
Nystagmus.
Ataxia.
Lethargy.
In CNS, look for necrosis, hemorrhage, or other degenerative changes in:
Mamillary bodies (most cases)
Less frequently in:
Thalamus.
Hypothalamus.
Periaqueduct in midbrain.
Floor of 4th ventricle.
Anterior cerebellum.
key words: brain, JB
373
BASSEN-KORNZWEIG SYNDROME.
Clinically is very similar to Friedreich's ataxia.
Look for:
Celiac syndrome.
Pigmentary retinal degeneration.
Acanthocytosis.
Abetalipoproteinemia.
key words: brain, JB
374
SCHWANN CELL.
Cell that wrap around axons to form the onion-skinned myelin sheath
of peripheral nerves.
The neoplastic variant of these cells populate schwannomas,
and form a large part of the cell population of neurofibromas.
key words: brain, JB
375
NERVE CELL CHROMATOLYSIS.
After amputation of a substantial part of the axon,
the chromophilic substance in the nerve cell body is altered.
The nucleus becomes eccentrically located (it is normally centrally located)
and the basophilic material in the cytoplasm is concentrated
in the cell periphery.
key words: brain, JB
376
MARINESCO BODIES.
Small round eosinophilic inclusions in the neurons
(particularly the neurons of the substantia nigra).
No pathological significance but seen more often in the elderly.
key words: brain, JB
377
BUNINA BODY.
Eosinophilic inclusions in the cytoplasm of anterior horn cells
(spinal cord) seen in amyotrophic lateral sclerosis.
key words: brain, JB
378
BRAIN AREAS MOST EASILY (AND QUICKLY) DAMAGED BY HYPOXIA.
Look for:
Ammon's horn (of hippocampus) necrosis.
Cerebellar cortex necrosis.
Laminar or focal damage of cerebral cortex.
Necrosis of globus pallidus.
When performing the autopsy, if there is no gross evidence of hypoxia,
take blocks from areas suspected clinically to be sites
of cerebral ischemia, as well as the cornu ammonis and the cerebellum.
key words: brain, JB
379
HEAT STROKE.
Can be associated with:
Rhabdomyolysis.
Disseminated intravascular coagulopathy (DIC).
key words: brain, JB
380
DERMOID VERSUS EPIDERMOID CYSTS OF THE CNS.
Epidermoid cysts are lined exclusively by stratified squamous epithelium.
Dermoid cysts are lined by stratified squamous epithelium,
plus other elements of skin appendage, such as hair follicles,
sebaceous glands, and sweat glands.
In the spinal cord, most dermoid cysts occur in the lumbosacral region.
Symptoms resulting from these cysts usually occur in patients
under 20 years for the intraspinal lesions and in the 20's
for patients with intracranial lesions.
--------------------
Rubinstein LJ. Tumors of the nervous system. Armed Forces Institute
of Pathology, Washington, D.C. p. 288, 1972.
key words: brain, JB
381
CYSTIC LESIONS OF THE CNS.
Arachnoid cyst.
Colloid cyst of third ventricle.
Craniopharyngioma.
Cystic astrocytoma.
Dermoid cyst.
Epidermoid cyst.
Hemangioblastoma.
Spinal epithelial cyst, enteric cyst.
key words: brain, JB
382
ACOUSTIC NEUROMA: OFTEN A MISNOMER.
The term vestibular schwannoma may be more appropriate,
because the tumors are principally composed of Schwann cells,
and typically involve the vestibular rather than the acoustic
division of the 8th cranial nerve.
key words: brain, JB
383
CLINICAL SYMPTOMS OF VESTIBULAR SCHWANNOMA (ACOUSTIC NEUROMA).
Progressive sensorineural hearing loss (98% of patients).
Late manifestations are due to mass effect on adjacent brain structures:
Headache.
Ataxia.
Cerebellar signs.
Cranial neuropathies.
key words: brain, JB
384
LISSENCEPHALY
Brain malformation
The cerebral surface is smooth
Agyria (absent gyri) is a type of lissencephaly, as is pachygyria (broad
gyri)
Due to neuronal migration defect in cerebral cortex. Grey matter
normally has well-defined neuron layers, but the lissencephalic grey
matter is widened, with dispersed (scattered) neurons.
Classic lissencephaly is associated with mental retardation and
neurologic abnormalities
--------------------
Dobyns WB, Reiner O, Carrozzo R, Ledbetter DH. Lissencephaly: a human
brain malformation associated with deletion of the LIS1 gene located at
chromosome 17p13. JAMA 270:2838-2842, 1993
key words: brain, malformation, JB
385
AMEBIC MENINGOENCEPHALITIS.
Usually due to Naegleria:
Acquired by swimming in fresh warm water.
Seen most often in children.
Almost always fatal.
Sometimes caused by Acanthamoeba:
Not always associated with fresh water swimming.
Produces a granulomatous response in the brain (unlike Naegleria).
key words: brain, microbiology, JB
386
IS THE TRANSGENIC MODEL OF ALZHEIMER'S DISEASE A VALID MODEL?
The transgenic model of Alzheimer's disease involves
inserting the beta-amyloid gene into the strain,
and studying the resultant lesions that occur in the CNS.
Gerald Higgins of the NIH is currently under investigation
for possibly misrepresenting the pathologic identity of lesions
in the brain of transgenic mice.
Dr. Higgins reported that the mouse lesions were plaques
and neurofibrillary tangles, like the human Alzheimer lesions.
Other researchers claim that no such lesion occurs
in the transgenic mouse model.
--------------------
Marx J. Major setback for Alzheimer's models. Science 255:1200-1201, 1992.
key words: brain, molecular biology, JB
387
CEREBRAL PALSY.
Cerebral palsy is a rather non-specific term encompassing
many non-progressive motor disorders (impairment of voluntary movement)
that result from gestational or perinatal CNS damage.
Occurs in about 1-2 per thousand children.
Occurs in up to 1 in 100 premature babies (particularly with
the manisfestation is spastic paraplegia).
A number of syndrome categories are described, including spastic,
athetoid, ataxic and mixed.
key words: brain, nervous system, paralysis, pediatric, JB
388
PATHOLOGY OF WERNICKE-KORSAKOFF SYNDROME.
Symmetric lesions of:
Anterior lobe of the cerebellum, particularly the vermis.
Floor of the 4th ventricle.
Mamillary bodies (always).
Paraventricular regions of the thalamus and hypothalamus.
Peraqueductal region of the midbrain.
Look for loss of neurons and a reactive gliosis in long-standing lesions.
Amnestic syndrome (Korsakoff) is due to lesions in the diencephalon.
key words: brain, neurology, alcohol, abuse, dementia, JB
389
SSPE.
Also known as:
Subacute sclerosing panencephalitis.
Dawson's inclusion body encephalitis.
Van Bogaert's encephalitis.
Subacute inclusion body encephalitis.
key words: brain, neurology, JB
390
PICK'S DISEASE.
There is no way during life (short of a brain biopsy)
of distinguishing Alzheimer's disease from Pick's disease.
Nor is it of any practical importance to the patient.
At autopsy look for:
Ballooned nerve cells in the atrophic regions.
Spherical intracytoplasmic inclusions that stain with silver.
key words: brain, neurology, JB
391
HALLEVORDEN-SPATZ DISEASE.
Often familial and autosomal recessive
Pigmented ferruginous material in the globus pallidus and substantia nigra.
Look for extrapyramidal dysfunction:
Rigid movements.
Choreoathetosis.
Beginning in childhood.
Death often occurs within 10 years of clinical onset.
At autopsy look for:
Rust-brown globus pallidus and substantia nigra.
On microscopy look for:
Axonal spheroids.
key words: brain, neurology, JB
392
SPINAL FORM OF MULTIPLE SCLEROSIS (MS).
MS may preferentially involve the spine.
In the differential diagnosis are:
Cervical spondylosis.
Subacute combined degeneration.
Spinal cord compression small vessel disease.
Transverse myelitis.
Tabes dorsalis.
key words: brain, neurology, JB
393
RILEY-DAY SYNDROME.
Look for:
Decreased lacrimation.
Transient skin blotching.
Attacks of hypertension.
Episodes of hyperpyrexia and vomiting.
Impairment of taste discrimination.
Relative insensitivity to pain.
Emotional instability.
key words: brain, neurology, JB
394
HUNTINGTON'S CHOREA.
At autopsy look for:
Atrophic brain.
Striking atrophy of caudate.
Less dramatic atrophy is seen in putamen and globus pallidus.
key words: brain, neurology, JB
395
PSEUDOBULBAR PALSY.
Can be caused by multiple lacunae (lacunar strokes)
of corticospinal and corticobulbar tracts.
Look for:
Bilateral upper motor neuron signs.
Dysarthria.
Dysphagia.
Paroxysms of excessive crying or laughing.
Short-stepped gait.
The term `bulbar' refers to the nuclei of the cranial nerves.
key words: brain, neurology, stroke, vascular, JB
396
MULTIPLE SCLEROSIS VERSUS ASTROCYTOMA.
MS can mimic glioma clinically, radiologically and even histologically.
On histology, look for:
Foamy macrophages.
Sheets of well-formed gemistocytes.
Prominent inflammatory infiltrate.
Most often seen in white matter.
Generally well defined borders.
Lack of vascular hyperplasia.
--------------------
Zagzag D, Miller DC, Kleinman GM, Abati A, Donnenfeld H, Budzilovich GN.
Demyelinating disease versus tumor in surgical neuropathology: clues to
a correct pathological diagnosis. Am J Surg Pathol 17:537-545, 1993.
key words: brain, neurology, tumor, glioblastoma, JB
397
CYTOLOGIC DEGENERATION RESULTING FROM CUT AXON.
Changes are not visible for about a day (by light microscope).
Look for:
Cell body swelling (the cell body is the portion
of the cell containing the nucleus).
Fragmentation of Nissl substance.
Nucleus becomes eccentric.
Angularity of the cell body lost (cell rounds up).
key words: brain, neuron, JB
398
MOBIUS SYNDROME.
Occurs following in utero or perinatal brain hypoxia.
Damage to brain stem structures limited to necrosis
of selected cranial nerve (especially 6 and 7) nuclei.
Very rare.
Look for ferrugination of neurons.
key words: brain, pediatric, ischemia, neonatal, newborn, JB
399
PLEOMORPHIC XANTHOASTROCYTOMA.
Usually seen in teenagers or young adults.
Usually superficial tumor (seems to sit atop the brain surface).
Usually seen as a firm plaque that often lies on a cyst
filled with clear fluid.
Histologic characteristics:
Closely packed pleomorphic cells with abundant pink cytoplasm.
Foci of perivascular lymphocytes.
Sometimes cells contain eosinophilic granular bodies.
--------------------
Burger PC, Scheithauer BW. Atlas of Tumor Pathology (Third Series,
Fascicle 10) Tumors of the Central Nervous System. Armed Forces Institute
of Pathology, Washington, DC, p. 96, 1994.
key words: brain, pediatric, JB
400
MILLER-DIEKER SYNDROME
Consists of:
lissencephaly
abnormal facial appearance
sometimes other birth defects
--------------------
Dobyns WB, Reiner O, Carrozzo R, Ledbetter DH. Lissencephaly: a human
brain malformation associated with deletion of the LIS1 gene located at
chromosome 17p13. JAMA 270:2838-2842, 1993
key words: brain, pediatric, malformation, JB
Last modified: December 5, 2006