Pathology Nervous System
Terms
undefined, object
copy deck
- What are neural tube defects
- A group of disorders characterized by incomplete closure of the neural tube in early gestation which results in dorsal midline defects at birth
- What structures can be involved with neural tube defects
- Vertebrae, skull, brain, spinal cord, and meninges
- Neural tube defects are associated with an increase in what in the maternal serum
- α-fetoprotein
- What are 3 possible reasons for neural tube defects
-
Presence of pathologic state in utero at time of neural tube closure (metabolic, nutritive, toxic, or infective causes)
Faulty implantation of placenta
Genetic abnormalities - What is the most common neural tube defect
- Spina bifida
- What is the defect in spina bifida
- Failure of posterior vertebral arches to close
- What is spina bifida occulta
- Same as spina bifida, but with no clinical abnormalities. Often there are only one or two vertebral arch defects
- What physical finding can be the only clue to spina bifida occulta
- Doral midline tuft of hair, overlying the site of defective vertebra
- What malformation can be associated with lumbar spina bifida
- Arnold-Chiari malformation
- What is a meningocele
- Herniation of meninges (arachnoid, dura) through a vertebral defect
- What is meningomyelocele
- Herniation of meninges and spinal cord through a vertebral defect
- What is the most severe neural tube defect
- Anencephaly
- Describe the clinical features of anencephaly
- Diminished or absent fetal brain tissue, usually associated with absence of overlying skull. Cerebral hemispheres, diencephalon, and midbrain can also be absent
- In anencephaly, what is exposed instead of fetal brain tissue
- A mass of undifferentiated vascular tissue
- What is hydrocephalus
- Increased volume of cerebrospinal fluid within the cranial cavity
- Name 4 types of hydrocephalus
-
Internal hydrocephalus
External hydrocephalus
Communicating hydrocephalus
Noncommunicating hydrocephalus - What is the difference between internal and external hydrocephalus
-
Internal: Increased CSF in the ventricles
External: Increased CSF in the subarachnoid space - What is the difference between communicating and noncommunicating hydrocephalus
-
Communicating: CSF can freely flow between ventricles and spinal subarachnoid space
Noncommunicating: The flow of CSF is obstructed between the ventricles and spinal subarachnoid space, causing proximal dilation of the ventricular system - What can often be seen in infants with hydrocephalus
- Marked enlargement of the skull
- Why does enlargement of the skull occur in infants with hydrocephalus
- Cranial sutures are not closed yet
- What are the causes of noncommunicating hydrocephalus
-
Anything can obstruct the CSF flow, including:
Congenital malformations
Inflammation
Tumors
Choroid plexus papilloma (rare; produces excess CSF) - What is hydrocephalus ex vacuo
- Apparent enlargement of ventricles because of decreased cerebral mass, not because of obstruction or increased CSF production
- Name two diseases characterized by decreased cerebral mass
-
Ischemic brain atrophy
Alzheimer disease (advanced) - What is Arnold-Chiari malformation
- Caudal (downward) displacement of medulla and cerebellum through foramen magnum into the cervical vertebral canal. It can be associated with lumbar spina bifida
- What defect is commonly associated with Arnold-Chiari malformation
- Thoracolumbar meningomyelocele
- Name 2 consequences of Arnold-Chiari malformation
-
Pressure atrophy of displaced brain tissue
Hydrocephalus, resulting from obstruction of CSF outflow tract - What is fetal alcohol syndrome
- A spectrum of characteristic dysmorphic features and developmental defects resulting from maternal alcohol intake during pregnancy
- Name 6 features that can be found in fetal alcohol syndrome
-
Interuterine growth retardation and subsequent growth failure
Microcephaly
Mental retardation
Micrognathia (small mandible)
Short palpebral fissures
Atrial septal defect - What is Bourneville disease
- Aother name for tuberous sclerosis syndrome
- What is the pathogenesis of the tuberous sclerosis syndrome
- Disorder of migration and arrested maturation of neural ectoderm, resulting in hamartomas (tubers) of the brain, retina, and viscera
- Name 4 features of tuberous sclerosis syndrome
-
Multiple tubers in the cerebral cortex and periventricular areas
Adenoma sebaceum of the skin (primarily facial)
Angiomyolipoma of the kidney
Rhabdomyoma of the heart - What is the pathology of the “tuber†in tuberous sclerosis
- Proliferations of atypical multinucleated astrocytes, appearing macroscopically as small, white nodules
- What is seen on the skin of a tuberous sclerosis patient under an ultraviolet Wood lamp
- Discrete areas of hypopigmentation known as “ash-leaf spotsâ€
- What is the common clinical presentation of patients with tuberous sclerosis syndrome
- Infantile seizures and mental retardation
- What is agenesis of the corpus callosum
- Complete or partial absence of the corpus callosum, wherein the only connection between the 2 cerebral hemispheres is at the brainstem. It is often asymptomatic
- What is von Recklinghausen disease
- An autosomal dominant disorder characterized by café au lait spots, multiple cutaneous neurofibromas, and Lisch nodules
- What is another name for von Recklinhausen disease
- Neurofibromatosis
- What are café au lait spots
- Small areas with irregular margins of increased pigmentation on the skin
- What are Lisch nodules
- Pigmented nodules of the iris, consisting of melanocytes
- Name the 2 types of neurofibromatosis, and the characteristics associated with each
-
Peripheral (Type 1): Skin lesions, dermal and peripheral nerve tumors
Central (Type II): Bilateral schwannomas of the acoustic nerve, and associated meningiomas, gliomas, and neurofibromas - Name 4 hereditary degenerative disorders of the nervous system and identify their pattern of inheritance
-
Huntington disease (AD)
Wilson disease (AR)
Lipid storage diseases (eg Tay-Sachs disease and Niemann-Pick disease)
Friedrich ataxia (AR) - What is the most common disorder of the central nervous system
- Cerebrovascular disease; third most common cause of death in the US
- Name 2 major categories of cerebrovascular disease
-
Infarction (more common)
Hemorrhage - What are transient ischemic attacks
- Episodes of focal neurologic defects caused by temporary lack of cerebral blood flow, with complete resolution of deficits
- How long do transient ischemic attacks last
- Normally, a few minutes, but they can last up to 24 hours
- What are some common neurologic defects seen in transient ischemic attacks
- Amaurosis fugax (temporary blindness), hemiplegia, and other cranial nerve defects
- If transient ischemic attacks are present, there is increased risk for what
- Increased risk of cerebral infarct (stroke)
- What are 2 mechanisms of brain infarction
- Occlusion of the arterial blood supply to the brain from thrombosis, or embolism
- What is the most common cause of vascular thrombosis
- Atherosclerotic plaques in blood vessels. They can rupture and initiate the coagulation cascade
- Name the 3 most common sites of cerebral thrombosis
-
Bifurcation site of common carotid into internal carotid and external carotid arteries
Branching sites of circle of Willis, especially the middle cerebral artery
Vertebral and basilar arteries, especially bifurcation sites - What clinical findings can be seen with arterial obstruction of the middle cerebral artery
-
Findings depend on extent of collateral circulation, but may include:
Contralateral paralysis
Motor and sensory deficits
Aphasias - Name 5 causes of embolic occlusion
-
Cardiac mural thrombi
Valvular vegetations, seen in infective endocarditis
Tumor cells
Air bubbles
Fat droplets - What is the most common site of embolic occlusions
- Middle cerebral artery
- What are lacunae
- Small healed infarcts that appear grossly as “pits†in brain matter
- What are some clinical manifestations of lacunar strokes if the obstruction of vessels occurs in the internal capsule
- Pure motor deficits
- What are some clinical manifestations of lacunar strokes if the obstruction of vessels occurs in the thalamus
- Pure sensory deficits
- Where are the 2 types of hemorrhagic brain disease
-
Intracerebral hemorrhage (brain substance)
Subarachnoid hemorrhage (subarachnoid space) - What are 4 predisposing conditions that increase the risk of intracerebral hemorrhage
-
Hypertension (most common)
Coagulation disorders, including thrombocytopenia
Hemorrhage within primary or metastatic cerebral neoplasms
Leukemia, in which neoplastic cells obstruct small vessels - Where are the 4 most common sites of intracerebral hemorrhage
-
Frontal lobe
Basal ganglia
Cerebellum
Pons - What develops in the brain as a result of chronic hypertension
- Charcot-Bouchard aneurysms
- Are Charcot-Bouchard aneurysms likely to rupture into brain parenchyma
- Yes
- What increases risk of Berry aneurysms rupturing
- Hypertension
- What type of aneurysm can rupture into the subarachnoid space
- Berry aneurysms, commonly found in the circle of Willis
- Name 3 other causes of subarachnoid hemorrhage
-
Arteriovenous malformation
Trauma
Hemorrhagic diatheses - What is the most common cause of subarachnoid hemorrhage
- Trauma
- What is the #1 cause of most head and spine injuries
- Motor vehicle accidents
- Name 4 types of injury to the brain in head trauma
-
Intracranial hemorrhage (epidural, subdural, subarachnoid)
Concussion
Contusion
Laceration - What artery is injured in an epidural hemorrhage
- Middle meningeal artery
- How is the middle meningeal artery injured
- Laceration from skull fracture
- What is the clinical presentation of epidural hemorrhage
- First, loss of consciousness immediately after the injury. Then, a lucid interval, followed by acute signs of increased intracranial pressure
- What causes intracranial pressure in an epidural hematoma
- Hematoma external to the dura mater presses inward, causing local brain compression
- What is the treatment for epidural hemorrhage
- Immediate surgical decompression to prevent subtentorial herniation
- What vessels are injured in a subdural hematoma
- Most commonly, the bridging veins from the cerebrum to venous sinuses in the dura mater
- Name 2 causes of subdural hematoma
- Blow to the head, commonly in the frontal or occipital regions; Birth injury
- What is the clinical presentation of subdural hematoma
- More insidious signs of decreasing mental status and enlargement of the hematoma can occur days to weeks after seemingly insignificant head injury
- Does the enlargement in a subdural hematoma result from the bridging vein still hemorrhaging days to weeks after the injury
- No; the enlarging hematoma is thought to result from osmotic properties of water movement into the collection of blood
- Describe the course of a concussion
- It is usually associated with loss of consciousness, characterized by temporary widespread brain paralysis without obvious organic pathology, usually associated with complete recovery
- What is hypothesized to be the mechanism of injury of a concussion
- Rotational or shearing strains on the brain
- What is a contusion brain injury
- Linked to a “bruise†on the brain, it results from torn capillaries from a blow to the calvarium
- What are 2 types of contusions
-
Coup: Lesion is located directly beneath area of impact
Contrecoup: Lesion is opposite to the area of impact - What is the clinical presentation of a contusion
- Loss of consciousness, possibly progressing to coma or death
- What is the gross appearance of an acute contusion
-
Swollen edematous gyri
Petechial hemorrhages - What is the gross appearance of an old contusion injury
- Sunken areas of brain, with small cysts
- What is the microscopic appearance of an old contusion injury
- Gliosis
- What is the microscopic appearance of an acute contusion injury
- Edematous cortex and subcortical white matter; fresh pericapillary hemorrhages
- What are Duret hemorrhages
- The petechiae seen in acute contusions
- What is a cord crush injury
- Compression and contusion of the spinal cord
- What is the common mechanism of injury in a cord crush injury
- Dislocation of vertebra, most commonly in lower cervical area, following forcible flexion as in a motor vehicle accident
- What is herniated in a “slipped diskâ€
- Nucleus pulposus, the center of the intervertebral disc, through a defect in the annulus fibrosis, causing pressure on nerve roots
- What is the most common area for a slipped disk
- Lumbrosacral: L4-5 or L5-S1 discs
- What is the common clinical presentation of a slipped disk
- Sciatica, or lower back pain after mild or moderate trauma
- What is the most common bacterial infection of the CNS
- Bacterial meningitis
- In what population is bacterial meningitis most common
- Children
- Name 6 causative microorganisms of bacterial meningitis
-
Neisseria meningitidis
Streptococcus pneumoniae
Haemophilus influenzae type b
Eschericia coli
Group B Streptococcus
Listeria monocytogenes - What organisms cause bacterial meningitis in newborns
- Group B Strep and E. coli
- What organisms cause bacterial meningitis in children
- S. Pneumoniae and H. influenzae
- What organisms cause bacterial meningitis in adolescents and adults
- Meningococcus and pneumococcus
- What organisms cause bacterial meningitis in the elderly
- Listeria monocytogenes and pneumococcus
- How do pathogens obtain access to the meninges
- Direct invasion (from facial sinuses or middle ear); Hematogenous seeding
- What are the 3 classic clinical signs of bacterial meningitis
-
Mental status changes
Fever
Nuchal rigidity (neck stiffness) - What are some other signs of clinical meningitis
- Vomiting, headache, confusion, and seizures
- What are the 3 findings in CSF diagnostic for bacterial meningitis
-
Increased protein
Decreased glucose (<2/3 serum glucose)
Many polymorphonuclear neutrophils (PMNs) - What will be noted about the opening pressure on lumbar puncture for a patient with bacterial meningitis
- Increased pressure
- What imaging test should be performed for bacterial meningitis if papilledema or focal neurologic signs are present
- Head CT scan before lumbar puncture, to rule out increased intracranial pressure from hydrocephalus or mass lesion
- What can occur if a mass lesion is present
- Risk for brain herniation into spinal canal when pressure is released at the site of a lumbar puncture
- What are the gross pathologic findings of bacterial meningitis in the subarachnoid space
- Purulent exudate
- What is the most common etiology of cerebral abscess
- Secondary infection from primary sources elsewhere in the body
- Name 5 common primary sources of cerebral abscess
-
Otitis media
Frontal sinusitis
Mastoiditis
Lung abscess, empyema, or other bronchopulmonary infection
Infective bacterial endocarditis - What are the clinical symptoms of cerebral abscesses
- Increased ICP and source of primary infection
- What are the CSF findings of cerebral abscesses
- Increased opening pressure, slightly increased protein and lymphocytes, and no change in glucose
- What organisms are seen in the CSF with brain abscesses
- None are usually seen, unless rupture of abscess has occurred
- What are the gross pathologic findings with brain abscesses
- Cavitary lesion in the brain filled with thick exudate, walled off by edematous tissue
- What can occur if infection spreads beyond abscess walls
- Encephalitis
- What part of the nervous system is the most common site of tuberculous infection
- Meninges
- How do mycobacteria gain access to the meninges
- Miliary dissemination from another source elsewhere in the body
- What are the clinical features of tuberculous infection of the meninges
- Gradual onset of anorexia, weight loss, and night sweats. Patient may also have mood changes, periods of drowsiness and delirium, and intermittent lucid intervals
- What are the CSF findings with meningeal tuberculosis
-
Increased lymphocytes
Significantly increased protein
Decreased glucose
Acid-fast bacilli in CSF - What are the gross pathologic findings in tubercular meningitis
- Gray-white thin exudate in meninges, pooling in the basilar cisterns and sylvian fissure; Tubercles (round white nodules) at the periphery
- What is the microscopic pathology in meningeal tuberculosis
- Granulomas composed of lymphocytes and large mononuclear cells; Tubercle bacilli
- What are common pathogens of fungal infection in the CNS
- Cryptococcus neoformans; Coccidioides immitis; Aspergillus; Histoplasma
- What predisposes an individual to fungal infection
- Impaired immunity
- What is toxoplasmosis
- Parasitic infection in which the pathogen is Toxoplasma gondii
- What is the source of toxoplasmosis in neonates
- Transmission transplacentally from infected mother
- What are some modes of toxoplasmosis infection
- Ingestion of foods contaminated by animal urine or feces; Contamination from household pets (ie cats)
- What are three neurologic characteristics of congenital toxoplasmosis infection
-
Hydrocephalus
Microcephaly
Seizures - What is the characteristic finding of toxoplasmosis on radiologic studies
- Periventricular calcifications
- Name the 3 areas of toxoplasma involvement in the brain
- Cerebral cortex; Basal ganglia; Retina
- What is the most common site of toxological infection in adults
- Lymph nodes
- What is another name for viral meningitis
- Aseptic meningitis
- How are the clinical findings in viral meningitis different from bacterial meningitis
- None; they are the same: fever, headache, and nuchal rigidity
- What are the CSF findings in viral meningitis
-
Increased lymphocytes
Moderate increase in protein
Normal glucose - What are the changes found in the brain substance occurring in meningoencephalitis or encephalitis
-
Perivascular cuffing (mononuclear cell infiltrate in the Virchow-Robin spaces around the vasculature)
Inclusion bodies in neurons or glial cells
Glial nodules (nonspecific proliferation of microglia) - Name 6 examples of CNS viral infection
- Arbovirus encephalitis (St. Louis, Eastern equine, Western equine); Herpes simplex; Poliomyelitis; Rabies; Cytomegalovirus; HIV
- What part of the brain is affected in Herpes simplex encephalitis
- Temporal lobe
- What happens to the brain in Herpes simplex encephalitis
- It becomes swollen, hemorrhagic, and necrotic
- What deteriorates in poliomyelitis
- Anterior horn cells of spinal cord
- What are the clinical manifestations of rabies
- Severe encephalitis with increased excitability of the CNS. Muscle contractions and convulsions can occur after minimal stimuli
- What are three histologic findings of rabies
-
Neuronal degeneration
Perivascular cuffing in brainstem and spinal cord
Negri bodies (eosinophilic intracytoplasmic inclusion bodies) - Where are Negri bodies found
- Hippocampus and cerebellum (Purkinje cells)
- What is the characteristic histology of CMV infection
- Giant cells with eosinophilic inclusions involving nucleus and cytoplasm
- What can be seen on radiologic evaluation of the brain in CMV infection
- Periventricular calcifications
- What is the most common clinical presentation of HIV nervous system involvement
- AIDS dementia complex
- Name 4 examples of suspected slow virus infection
- Kuru; Creutzfeldt-Jakob disease; Subacute sclerosing panencephalitis; Progressive multifocal leukoencephalopathy
- What characterizes slow virus infections
- Long incubation period, little inflammatory response, and progressive deterioration
- What is the histology of slow virus infections
- Spongiosis, with numerous clusters of small cysts in the CNS gray matter
- What 2 diseases do you suspect if dementia occurs acutely
-
Creutzfeldt-Jakob disease
Normal pressure hydrocephalus - Where was kuru first documented
- A cannibal tribe in New Guinea, which ritualized the practice of consuming the human brain
- What is subacute sclerosing panencephalitis
- Persistent infections with measles virus, usually infected in infancy but asymptomatic until late childhood or early adolescence. Prognosis is slowly progressive and usually fatal
- What is atypical about the measles virus
- Lack of M component of the virus, responsible for extracellular spread; perhaps responsible for slow infection
- What is PML
- Rapidly progressive demyelination in multiple foci throughout the brain
- What percentage of all nervous system disorders are neoplasms
- About 10%
- What is the incidence of neoplastic disease of the spinal cord
- Very rare
- In adults, are the majority of intracranial neoplasms above or below the tentorium
- Supratentorial
- In children, are the majority of intracranial neoplasms above or below the tentorium
- Infratentorial
- Are CNS tumors the most common malignancy in children
- No, but they are the 2nd most common after leukemia
- Where do most primary malignant CNS tumors metastasize
- They usually don’t metastasize
- What can be some direct effects of intracranial tumors
- Neurologic dysfunction, with focal deficits depending on location of neoplasm; Electrically unstable neurons, with predisposition to epileptiform activity
- Name 6 secondary effects of intracranial tumors
- Brain edema; Compression with resultant deficiency of vascular supply; Ischemia; Necrosis; Herniation of brain and/or cerebellar tonsils; Hydrocephalus
- What can often be seen on funduscopic examination in a patient with intracranial tumors
- Papilledema (swelling caused by edema of optic nerve papillae) and retinal vein engorgement
- Name the 4 most common intracranial tumors in adults
-
Glioblastoma multiforme
Metastatic tumors (from extracranial primary sites)
Meningioma
Acoustic neuroma - Name the 4 most common intracranial tumors in children
-
Medulloblastoma
Ependymoma
Craniopharyngioma
Astrocytoma - Name 3 other neoplasms of the CNS found in children
-
Retinoblastoma
Neuroblastoma
Hemangioblastoma - How does a glial tumor grow differently from a non-glial tumor
- Glial tumors grow by infiltration, and thus cannot be completely removed. Non-glial tumors grow by expansion and are more likely to be totally resected
- What is the function of a normal astrocyte
- In reaction to injury, astrocytes expand their cytoplasm and form glial fibrils
- What is the most common location of astrocytomas in adults
- Central white matter of the cerebrum
- What is the most common location of astrocytomas in children
- Cerebellum
- How are astrocytomas characterized
- Based on histology; Grade I-Grade IV
- What is the treatment of astrocytoma
- Surgical resection, with excellent prognosis if completely removed
- What is another name for Grade IV astrocytoma
- Glioblastoma multiforme, the most common primary intracranial neoplasm
- What is the peak age group for glioblastoma multiforme
- Later middle age
- Describe the histology of glioblastoma multiforme
-
Marked anaplasia and pleomorphism
Vascular changes with endothelial hyperplasia
Many mitoses - What pattern of tumor cells encompass areas of necrosis and hemorrhage
- Pseudo-palisade arrangement at the periphery
- What is the prognosis of glioblastoma multiforme
- Very poor, usually death within 1 year
- What is an oligodendrocyte
- A neuroglial cell, whose surface membrane coils around neuronal axons to form the myelin sheath in white matter
- How fast does oligodendroglioma proliferate
- Very slowly
- What age group is most commonly affected by oligodendroglioma
- Middle age
- What is the most common site of origin of oligodendroglioma
- Cerebral hemispheres
- Describe the typical morphology of oligodendroglioma
- Large round nuclei surrounded by a halo of clear cytoplasm, often called “fried egg appearanceâ€
- What is seen as typical morphology on oligodendroglioma
- Foci of calcification
- Where is the most common location of ependymoma
- Fourth ventricle
- What is the peak age group of ependymoma
- Children and adolescents, but any age group can be affected
- What may result from ependymoma growth
- Hydrocephalus due to obstructed CSF flow
- What is the pattern of the histology of ependymoma
- Rosettes with cells encircling vessels, or tubules with cells pointing toward a ventral lumen
- What is the proliferating cell type in a meningioma
- Arachnoid cell
- Characterize meningiomas
- Commonly benign and slow growing
- What is the second most common primary intracranial neoplasm
- Meningioma
- Why is surgery a feasible option with a meningioma
- Meningioma is external to the brain, and thus can be surgically removed
- Name common locations of meningioma
-
Convexities of the cerebral hemispheres
The parasagittal region
Falx cerebri
Sphenoid ridge
Olfactory area
Suprasellar region - What is the gross appeareance of meningioma
- Firm, rubbery tumors, white or reddish colored, clearly distinguished from brain parenchyma
- What is the appearance of a meningioma under the microscope
-
Whorled pattern spindle cells
Ovoid nuclei
Intranuclear vacuoles
Calcified psammoma bodies - What are psammoma bodies
- Microscopic concentric laminated mass of calcified material
- What is the age group most commonly affected by medulloblastoma
- Young children under 14 years of age
- Is medulloblastoma benign or malignant
- Highly malignant
- What area of the brain is usually involved in medulloblastoma
- Cerebellum
- What is the gross pathology of medulloblastoma
- Reddish gray, granular mass arising from roof of 4th ventricle
- What is the histology of medulloblastoma
- Rosette-patterned sheets of closely packed cells with little cytoplasm and a pseudorosette pattern
- What is meant by a pseudorosette
- Perivascular arrangement of tumor cells
- What does PNET stand for
- Primitive neuroectodermal tumor. Medulloblastoma is one of the small cell tumors of the nervous system
- What is the prognosis of medulloblastoma
- Poor; survival of 1-2 years after onset of symptoms is typical
- What is the age group most commonly affected by retinoblastoma
- Young children
- What percentage of cases of retinoblastoma results from sporadic mutation
- Approximately 60%
- How are 40% of retinoblastomas cases inherited
- Familial
- What is the genetic defect in retinoblastoma
- Homozygous deletion of retinoblastoma gene (chromosome 13)
- Is an attenuated form of retinoblastoma present if only one deletion exists
- No; both deletions are required for tumor to develop
- What is hemangioblastoma
- Tumor of blood vessel origin
- What area of the brain is most frequently affected by hemangioblastoma
- Cerebellum
- What are common clinical complaints of hemangioblastoma
- Difficulty with balance and walking
- What disease is associated with hemangioblastoma
- von Hippel-Lindau disease, with similar lesions in retina and other organs
- What are 3 neoplasms associated with von Hippel-Lindau disease
-
Hemangioblastoma
Renal cell carcinoma
Pheochromocytoma - What protein is sometimes produced by neoplastic hemangioblastoma cells
- Erythropoietin
- What can result from release of erythropoietin from hemangioblastoma cells
- Secondary Polycythemia
- What is the microscopic pathology of hemangioblastoma
- Variable presentation, from purely vascular to highly cellular, with large polygonal cells full of lipids
- What are two other names for schwannoma
- Neurilemoma, acoustic neuroma (if localized to CN VIII)
- What is the cell of origin in a schwannoma
- Schwann cell
- Are schwannomas benign or malignant
- Benign
- How fast do schwannomas proliferated
- They are slow growing, encapsulated tumors
- Where are schwannomas commonly located
- Posterior nerve roots and peripheral nerves
- What are 2 patterns of histology seen with schwannomas
-
Antoni type A neurilemoma: elongated cells with palisade nuclei, grouped in bundles
Antoni type B neurilemoma: less cellularity, similar pattern - What disease is associated with multiple neurofibromas
- von Recklinghausen disease
- From what cell are neurofibromas derived
- Schwann cells, involving peripheral nerves
- What are the 6 most common primary sites of malignancy that metastasize to the brain
- Lung; Breast (usually dura and skull); Skin; Kidney; GI tract; Thyroid
- How do most malignancies metastasize to the brain
- Usually metastasis to the brain is hematogenous, but direct invasion is also possible
- From what tissues is a craniopharyngioma derived
- The hypophyseal trunk or Rathke pouch
- What is a Rathke pouch
- Diverticulum from the embryonic buccal cavity, from which the anterior lobe of the pituitary develops
- What age group is most commonly affected by craniopharyngioma
- Children, averaging between 4-16 years old
- What clinical signs are evident with craniopharyngioma
- Visual complaints, hypothalamic syndromes
- What is the gross appearance of a craniopharyngioma
- Calcified, multiloculated mass of several centimeters, sometimes encapsulated by the surrounding brain, with cystic areas
- What is seen on skull radiograph of a craniopharyngioma that can suggest the diagnosis
- Plain films of the head will show characteristic calcifications
- What conditions increase the risk of developing primary lymphoma of the brain
- Conditions that cause patients to be Immunocompromised (eg AIDS, status post transplant)
- What is the most common primary brain neoplasm of Immunocompromised patients
- Lymphoma
- In the absence of immune deficiency, in what age group do primary lymphomas most commonly occur
- Patients in their 60s or 70s
- What are 3 clinical features of lymphoma of the brain
-
Headache
Seizures
Deficiency of higher neural function such as problems with memory - What is the gross pathology of lymphoma of the brain
- Usually multifocal, seen most often in the cerebrum, arising in the perivascular spaces
- What is the microscopic appearance of lymphoma of the brain
- Similar to the classic forms of lymphoma
- What are 2 characteristics of demyelinating diseases
-
Destruction of myelin
Preservation of axons - Which in primarily affected in demyelinating diseases, white or gray matter
- White matter
- Which is the most common of the demyelinating diseases
- Multiple sclerosis
- What are three common examples of demyelinating diseases
-
Multiple sclerosis
Acute disseminated encephalomyelitis
Guillain-Barre’ syndrome - What is the age group of peak incidence of MS
- 20-30 years old
- What is the etiology of MS
- Unknown; immune or viral theory postulated but not proven. It is thought to be multifactorial
- Is MS more common in men or women
- Slightly more common in women
- What evidence supports the theory of an immune system etiology in MS
- Increased incidence associated with HLA A3, B7, DR2, and DW2
- What is increased in the CSF in patients with MS and how is it detected
- Immunoglobulin, seen as multiple oligoclonal bands on electrophoresis
- What is the relationship of incidence of MS to geographic location
- Incidence is directly proportional to distance from the equator
- What are the morphologic changes of MS in the brain and spinal cord
- Multiple focal areas of demyelination known as plaques
- What is the microscopic appearance of areas of demyelination in MS
-
Localized edema, congestion, and microglial proliferation
Progressive astrocytosis and infiltration
Eventually, sclerotic plaque and reactive gliosis - What 3 sites are particularly affected in MS
-
Optic nerve
Brainstem
Paraventricular areas - What cells infiltrate MS plaques before reactive gliosis occurs
-
Helper CD4+ cells
Cytotoxic CD8+ T lymphocytes
Macrophages - What are the early clinical findings of MS
- Motor deficits of the distal lower extremities, visual disturbances and retrobulbar pain, sensory deficits, and sometimes bladder incontinence
- What is the classic Charcot triad of MS symptoms
-
Nystagmus
Intention tremor
Scanning speech