XXIII - The Nervous System (with pics) Flashcards
This pattern of neuronal cell injury leads to shrunken individual cell bodies and nuclei. They are prominently stained by eosin, leading to the term “red neurons.” SEE SLIDE 23.1.
Acute hypoxic/ischemic injury(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 860
These are round, faintly basophilic, PAS-positive, concentrically lamellated aggregates of polyglucosans that range between 5 and 50 micrometers, and are located wherever there are astrocytic end processes, especially in the subpial and perivascular zones, seen more frequently with advancing age. SEE SLIDE 23.2.
Corpora amylacea (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 861
Cells which produce myelin in the CNS.
Oligodendrocytes (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 861
Cells which line the ventricles, and are located in the region of the obliterated central canal of the spinal cord.
Ependymal cells (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 861
These are responsible for the secretion of CSF. It has a specialized epithelial covering with a fibrovascular stroma that may contain meningothelial cells.
Choroid plexus (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 861
These are bone marrow-derived cells that function as the phagocytes of the CNS.
Microglia (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 861
It is the accumulation of excess fluid within the brain parenchyma. The brain is softer than normal and often appears to “overfill” the cranial vault. In generalized edema the gyri are flattened, the intervening sulci are narrowed, and the ventricular cavities are compressed.
Cerebral Edema (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 861
This occurs when the integrity of the normal blood-brain barrier is disrupted. With increased vascular permeability, fluid shifts from the vascular compartment into the intercellular spaces of the brain.
Vasogenic edema (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 861
This is due to an increase in intracellular fluid secondary to neuronal, glial, or endothelial cell membrane injury, as might be encountered in an individual with a generalized hypoxic/ischemic insult or with exposure to some toxins.
Cytotoxic edema(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 861
Refers to the accumulation of CSF leading to dilation of the ventricular system which resulted from an obstacle or disruption of flow seen most commonly at the foramen of Monroe or aqueduct of Sylvius.
Noncommunicating hydrocephalus (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 862
Refers to the accumulation of CSF leading to dilation of the ventricular system due to reduced resorption of CSF. All of the ventricular system is enlarged.
Communicating hydrocephalus (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 862
This refers to dilation of the ventricular system with a compensatory increase in CSF volume secondary to a loss of brain parenchyma, as may occur after infarcts or with a degenerative disease.
Hydrocephalus ex vacuo (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 862
This ccurs when unilateral or asymmetric expansion of a cerebral hemisphere displaces the cingulate gyrus under the edge of falx. This may be associated with compression of branches of the anterior cerebral artery.
Subfalcine (cingulate) herniation(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 862
This occurs when the medial aspect of the temporal lobe is compressed against the free margin of the tentorium. As the temporal lobe is displaced, the third cranial nerve is compromised, resulting in pupillary dilation and impairment of ocular movements on the side of the lesion (“blown pupil”).
Transtentorial (uncinate) herniation (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 862
This refers to displacement of the cerebellar tonsils through the foramen magnum. This pattern of herniation is life-threatening, because it causes brain stem compression and compromises vital respiratory and cardiac centers in the medulla.
Tonsillar herniation (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 862
These linear or flame-shaped lesions usually occur in the midline and paramedian regions, which are hemorrhagic lesions that accompany transtentorial herniation. Presence of these lesion implies poor prognosis.
Duret hemorrhages(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 862
In the setting of this condition, the brain is swollen, with wide gyri and narrowed sulci. The cut surface shows poor demarcation between gray and white matter. Results from generalized reduction of cerebral perfusion, usually below systolic pressures of less than 50mmHg.
Global Cerebral Ischemia (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 863
These are wedge-shaped areas of infarction that occur in those regions of the brain and spinal cord that lie at the most distal fields of arterial perfusion. Usually seen after hypotensive episodes.
Border zone (“watershed”) infarcts. Most at risk: border zone between anterior and middle cerebral artery. (TOPNOTCH)Robbins Basic Pathology, 9th ed., p. 1264
Pattern of necrosis seen in nonhemorrhagic infarcts of the brain.
Liquefaction necrosis(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 863
The most frequent cause of subarachnoid hemorrhage. It is a thin-walled outpouching of an artery. At the neck of the aneurysm, the muscular wall and intimal elastic lamina stop short and are absent from the aneurysm sac itself; the sac is made up of thickened hyalinized intima. The adventitia covering the sac is continuous with that of the parent artery
Saccular (berry) aneurysm(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 866
Patients with this type of intracranial hemorrhage complains of having “the worst headache I’ve ever had”/ thunderclap headache.
Subarachnoid Hemorrhage (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 866
Most common location for berry/saccular aneurysms.
Anterior communicating artery in the Circle of WIllis (40%)(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 867
This is a disease in which amyloidogenic peptides are deposit in the walls of medium- and small-caliber meningeal and cortical vessels, which results in the weakening of the vessel wall and increases the risk of hemorrhage.
Cerebral amyloid angiopathy (CAA) (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 863
Hemorrhages associated with cerebral amyloid angiopathy (CAA) due to involvement of the cerebral hemispheres?
Lobar hemorrhages(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 863
A type of vascular malformation which are characterized by of ectatic venous channels.
Venous angiomas (varices) (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 868
Most common location for berry aneurysms.
Anterior communicating artery in the Circle of WIllis (40%)(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 867
The involved vessels in this condition resemble a tangled network of wormlike vascular channels. Microscopically, they are enlarged blood vessels separated by gliotic tissue, often with evidence of prior hemorrhage.
Arteriovenous malformations (AVM)(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 868
A type of vascular malformation which are characterized by microscopic foci of dilated, thin-walled vascular channels separated by relatively normal brain parenchyma and occurring most frequently in the pons.
Capillary telangiectasias(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 868
Minute aneurysms in vessels that are less than 300 micrometers in diameter, associated with chronic hypertension.
Charcot-Bouchard microaneurysms (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 868
This leads to accumulation of arterial blood between the dura and the skull. The expanding hematoma has a smooth inner contour that compresses the brain surface. Clinically, patients may experience a lucid interval between the moment of trauma and development of neurologic symptoms.
Epidural Hematoma. SEE SLIDE 23.3. (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 870
This is an inflammatory disorder that involves multiple small to medium-sized parenchymal and subarachnoid vessels and is characterized by chronic inflammation, multinucleated giant cells and destruction of the vessel wall. Affected individuals manifest a diffuse encephalopathic clinical picture, often with cognitive dysfunction; improvement occurs with steroid and immunosuppressive treatment.
Primary angiitis of the CNS (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 868
This describes reversible altered consciousness from head injury in the absence of contusion. The characteristic transient neurologic dysfunction includes loss of consciousness, temporary respiratory arrest, and loss of reflexes.
Concussion(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 869
Injury which may occur from collision of the brain with the skull opposite the site of impact.
Contrecoup injury(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 868
These are wedge shaped lesions of the brain parenchyma which occur secondary to trauma. The broad base of the wedge spans the surface and centered on the point of impact.
Contusions(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 868
Blood vessel involved in epidural hematoma.
Middle meningeal artery(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 870
Blood vessels involved in subdural hemorrhage.
Bridging veins(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 870
This is an extension of CNS tissue through a defect in the vertebral column, most commonly in the lumbosacral region. both The meninges and spinal cord parenchyma are included in the cystlike structure visible just above the buttocks.
Myelomeningocele. SEE SLIDE 23.4. (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 872
Herniation of the meninges through a defect in the vertebral column.
Meningocoele. SEE SLIDE 23.4. (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 872
This is a malformation of the anterior end of the neural tube, with absence of the brain and top of skull.
Anencephaly. SEE SLIDE 23.5. (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 872
This is a diverticulum of malformed CNS tissue extending through a defect in the cranium. It most often involves the occipital region or the posterior fossa.
Encephalocele. SEE SLIDE 23.5. (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 872
Characterized by an increased number of irregularly formed gyri that result in an irregular bumpy or cobblestone-like surface.
Polymicrogyria(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 872
Characterized by a disruption of the normal midline patterning. In severe forms the brain is not divided into hemispheres or lobes and may be associated with facial midline defects like cyclopia.
Holoprosencephaly (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 872
Consists of a small posterior fossa and a misshapen midline cerebellum with downward extension of vermis through the foramen magnum; hydrocephalus and a lumbar myelomeningocele are typically also present.
Arnold-Chiari malformation Type II(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 872
Consists of low-lying cerebellar tonsils which extend through the foramen magnum at the base of the skull. This can lead to obstruction of CSF flow and compression of the medulla, resulting in symptoms of headache or cranial nerve deficits.
Arnold-Chiari malformation type I(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 872
Cerebral malformation characterized by an enlarged posterior fossa. The cerebellar vermis is absent, and replaced by a large, midline cyst that is lined by ependyma and is contiguous with leptomeninges on its outer surface. SEE SLIDE 23.6.
Dandy-Walker malformation (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 872
Spinal cord abnormality characterized by a discontinuous or confluent expansion of the ependyma-lined central canal of the cord.
Hydromyelia(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 873
CSF findings in bacterial meningitis.
Increased pressureabundant neurophilsprotein - elevatedglucose - reduced(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 874
This is an inflammatory process of the leptomeninges and CSF within the subarachnoid space.
Meningitis (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 874
In acute cases of this condition, an exudate is evident within the leptomeninges over the surface of the brain. On microscopic examination, neutrophils fill the entire subarachnoid space in severely affected areas or may be found predominantly around the leptomeningeal blood vessels.
Acute meningitis(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 874
A form of neurosyphilis, resulting from damage to the sensory nerves in the dorsal roots producing impaired joint position sense and resultant ataxia, loss of pain sensation, leading to skin and “Charcot joints” (deformed bones). There is loss of both axons and myelin in the dorsal roots, with pallor and atrophy in the dorsal columns of the spinal cord.
Tabes dorsalis (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 875
Presents with generalized symptoms of headache, malaise, mental confusion, and vomiting. The subarachnoid space contains a gelatinous or fibrinous exudate, most often at the base of the brain, obliterating the cisterns and encasing cranial nerves. There may be discrete white granules scattered over the leptomeninges. Obliterative endarteritis may be seen.
Tuberculous meningitis (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 874
CSF findings in tuberculous meningitis.
Moderate pleiocytosis - predominantly monocytesprotein - elevatedglucose - moderately reduced/normal(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 874
Caused by invasion of the brain by Treponema pallidum and manifests as insidious but progressive loss of mental and physical functions with mood alterations (including delusions of grandeur), terminating in severe dementia.
Paretic neurosyphilis (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 874
This virus tends to localize in the paraventricular subependymal regions of the brain, which results in a severe hemorrhagic necrotizing ventriculoencephalitis and choroid plexitis.
Cytomegalovirus (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 877
These are discrete lesions with central liquefactive necrosis and a surrounding fibrous capsule. On microscopic examination, there is exuberant neovascularization around the necrosis that is responsible for the marked edema and formation of granulation tissue. Outside the fibrous capsule is a zone of reactive gliosis.
Brain Abscesses (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 876
The pathognomonic finding of this disease is a spongiform transformation of the cerebral cortex and deep gray matter structures (caudate, putamen); consists of a multifocal process that results in the uneven formation of small, empty, microscopic vacuoles of varying sizes within the neuropil and sometimes in the perikaryon of neurons. SEE SLIDE 23.7.
Creutzfeldt-Jakob Disease (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 880
Viral encephalitis which involves inferior and medial regions of the temporal lobes and the orbital gyri of the frontal lobes. Perivascular inflammatory infiltrates are usually present, and Cowdry type A intranuclear viral inclusion bodies can be found in both neurons and glia. SEE SLIDE 23.8.
Herpes Encephalitis(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 876
Reactivation of varicella in adults manifests as a painful, vesicular skin eruption in the distribution of one or a few dermatomes.
Shingles / Herpes Zoster(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 876
This lesion caused by JC virus, consist of patches of irregular, ill-defined destruction of the white matter that enlarge. Each lesion is an area of demyelination, in the center of which are scattered lipid-laden macrophages and a reduced number of axons.
Progressive Multifocal Leukoencephalopathy (PML) (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 877
These are predominantly benign tumors of adults, usually attached to the dura, and arising from the meningothelial cell of the arachnoid. Histologic patterns include syncitial, fibroblastic, psammomatous (SEE SLIDE 23.9), secretory and microcystic.
Meningiomas(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 885
Five most common primary sites of carcinoma which may metastasize to the brain.
LungBreastSkin (melanoma)KidneyGIT(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 885
These are infiltrative tumors that form gelatinous, gray masses, and may show cysts, focal hemorrhage, and calcification. On microscopic examination, the tumor is composed of sheets of regular cells with spherical nuclei containing finely granular chromatin (similar to normal oligodendrocytes) surrounded by a clear halo of cytoplasm. SEE SLIDE 23.10
Oligodendrogliomas(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 883
A nonimmune process characterized by loss of myelin involving the center of the pons, most often after rapid correction of hyponatremia.
Central pontine myelinolysis (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 889
These are inherited dysmyelinating diseases in which the clinical symptoms derive from either abnormal myelin synthesis or turnover.
Leukodystrophies (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 889
Profound memory disturbances as a result of thiamine deficiency.
Korsakoff syndrome(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 890
An autoimmune demyelinating disorder characterized by distinct episodes of neurologic deficits, separated in time, attributable to white matter lesions that are separated in space. Affected areas show multiple, well-circumscribed, slightly depressed, glassy, gray-tan, irregularly shaped lesions, termed “plaques”.
Multiple Sclerosis (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 887
This condition occurs in the setting of thiamine deficiency and chronic alcoholism. Characterized by foci of hemorrhage and necrosis, particularly in the mammillary bodies but also adjacent to the ventricle, especially the third and fourth ventricles.
Wernicke encephalopathy(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 890
Characterized by “flapping” tremor, depressed levels of consciousness, which may lead to coma. Result of decreased hepatic function.
Hepatic encephalopathy (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 891
It is the most common cause of dementia in the elderly, characterized by presence of plaques and neurofibrillary tangles, composed of tau proteins. SEE SLIDE 23.11.
Alzheimer’s disease(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 893
Mutation in Friedreich ataxia.
GAA trinucleotide repeat (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 895
This is a clinical syndrome characterized by masked facies, stooped posture, slowness of voluntary movement, festinating gait rigidity, and a “pill-rolling” tremor. There are single or multiple, intracytoplasmic, eosinophilic, round to elongated inclusions that often have a dense core surrounded by a pale halo or “Lewy bodies”. SEE SLIDE 23.12.
Parkinson disease (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 894
It is an inherited autosomal dominant disease characterized clinically by progressive movement disorders and dementia, with degeneration of the striatum (caudate and putamen).
Huntington Disease (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 894
Mutation in Huntington disease.
CAG trinucleotide repeats(TOPNOTCH)Robbins Basic Pathology, 8th ed., p 895
It is an autosomal recessive progressive illness, generally beginning in the first decade of life with gait ataxia, followed by hand clumsiness and dysarthria.
Friedreich ataxia (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 895
This is the most common form of neurodegeneration affecting the motor system. It is characterized by muscle atrophy and hypereflexia due to loss of both upper and lower motor neurons.
Amyotrophic Lateral Sclerosis (Motor Neuron Disease; Lou Gehrig’s Disease) (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 895
This is one of the most common life-threatening diseases of the peripheral nervous system. It may develop spontaneously or after a systemic infection (usually viral) or other stress. Usually presents with rapidly progressive, ascending motor weakness that may lead to death from failure of respiratory muscles.
Guillain-Barre Syndrome (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 899
These are benign tumors arising from Schwann cells, which are well-circumscribed encapsulated, firm, gray masses but may also have areas of cystic and xanthomatous change.
Schwannomas (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 899
Present in the dermis and subcutaneous fat, these well-delineated but unencapsulated masses are composed of spindle cells. The stroma of these tumors is highly collagenized and contains little myxoid material.
Cutaneous neurofibroma. SEE SLIDE 23.13. (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 899
These tumors may arise anywhere along a nerve, may be multiple, and is not easily separated from the nerve.
Plexiform neurofibroma. SEE SLIDE 23.13. (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 899
This autosomal dominant disorder is characterized by neurofibromas (plexiform and solitary), gliomas of the optic nerve, pigmented nodules of the iris (Lisch nodules), and cutaneous hyperpigmented macules (cafe au lait spots).
Type 1 Neurofibromatosis (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 901
This is an autosomal dominant disorder in which patients develop a range of tumors, most commonly bilateral vestibular (acoustic) schwannomas and multiple meningiomas.
Type 2 Neurofibromatosis (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 901
An autosomal dominant syndrome characterized by the development of hamartomas and benign neoplasms involving the brain and other tissues. The lesions are firm areas of the cortex that, in contrast to the softer adjacent cortex, have been likened to potatoes, hence the appellation “tubers.” SEE SLIDE 23.14.
Tuberous Sclerosis (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 901
An autosomal dominant inherited disease in characterized by development of hemangioblastomas within the cerebellar hemispheres, retina, and less commonly the brain stem and spinal cord. A cerebellar capillary hemangioblastoma, is the principal neurologic manifestation of the disease.
von Hippel-Lindau Disease (TOPNOTCH)Robbins Basic Pathology, 8th ed., p 901
What is the dominant histopathologic finding in Immune mediated neuropathies like Guillain- Barre Syndrome?
Inflammation of peripheral nerve, manifested as perivenular and endoneurial infiltration by lymphocytes, macrophages, and a few plasma cells. SEE SLIDE 23.15. (TOPNOTCH)
What is the most common type of peripheral neuropathy seen in adult-onset DM?
Symmetric neuropathy that involves distal sensory and motor nerves (TOPNOTCH)