A 30-year-old female is diagnosed with multiple sclerosis. What do the characteristic periventricular plaques on her MRI represent?
Areas of oligodendrocyte loss and reactive gliosis
Identify the histologic findings of this biopsy sample from an oligodendroglioma.
Fried egg cells (i.e., round nuclei with clear cytoplasm) and a chicken-wire capillary pattern
Identify the brain tumor associated with this MRI demonstrating a tumor in the cerebral hemispheres, crossing the corpus callosum.
What is the most common cause of dementia in the elderly?
Senile plaques and neurofibrillary tangles characterize what type of dementia?
The genes APP, presenilin-1, presenilin-2, and ApoE4 are associated with the familial form of what type of dementia?
Alzheimer's disease may cause amyloid angiopathy, which may result in what serious complication?
What is the difference between the Apo isoforms E2 and E4 in the pathogenesis of Alzheimer's disease?
The E4 isoform is a genetic risk factor for familial Alzheimer's disease, whereas the E2 isoform is protective against Alzheimer's disease
What is the second most common cause of dementia in the elderly after Alzheimer's Disease?
What degenerative disease of the cerebral cortex affects only the frontal and temporal lobes?
An elderly woman is increasingly socially inappropriate and inattentive, and she has difficulty speaking. What type of dementia is most likely to cause this her decrement in executive functioning?
What degenerative disease of the cerebral cortex is caused by an -synuclein defect?
Lewy body dementia
_____ bodies are characterized by intracellular aggregated τ-protein in neurons.
What degenerative disease of the cerebral cortex is associated with a rapidly progressive dementia (occurring over weeks to months), myoclonus, and a spongiform cortex?
What degenerative disease of the cerebral cortex is characterized by parkinsonism, dementia, and hallucinations?
Lewy body dementia
Name the pathologic proteins responsible for Creutzfeld-Jakob disease.
The intracellular neurofibrillary tangles found in patients with Alzheimer's disease are commonly made up of abnormally phosphorylated _____ protein.
What proportion of patients with Alzheimer;s disease have the familial form?
What potentially treatable forms of dementia must be ruled out before diagnosing a patient with Alzheimer's disease?
Wilson's disease, vitamin B12 deficiency, syphilis, and HIV
What will cerebrospinal fluid studies of a patient with multiple sclerosis show?
Increased immunoglobulin G protein; oligoclonal bands are considered diagnostic of multiple sclerosis
A patient presents with sudden loss of vision, internuclear ophthalmoplegia, hemiparesis, and bladder incontinence. What disease does she most likely have?
Histologically, what are the periventricular plaques seen in multiple sclerosis?
Areas of oligodendrocyte loss and reactive gliosis
Name five classic symptoms of multiple sclerosis. Use the mnemonic, SIN.
Scanning speech, Intention tremor, Incontinence, Internuclear ophthalmoplegia, Nystagmus
What is the treatment for multiple sclerosis?
-Interferon or immunosuppressant therapy, as well as symptomatic treatment for incontinence, pain, and spasticity
Which imaging modality is considered diagnostic of multiple sclerosis if it has a characteristic appearance?
Magnetic resonance imaging
Multiple sclerosis causes damage to which of the following: axons, neuron cell bodies, myelin?
What demographic group is most likely to be affected by multiple sclerosis (race, sex and age)?
White women 20-40 years of age
Is the course of multiple sclerosis usually rapidly progressive, chronic, insidious, or relapsing and remitting?
Relapsing and remitting
What syndrome is characterized by symmetric ascending muscle weakness that begins in the distal lower extremities and that typically occurs after or concurrent with an infection?
What is the mechanism by which the immune system is induced to destroy myelin in Guillan-Barr syndrome?
How long does it generally take patients to recover from Guillan-Barr syndrome?
Most patients recover in weeks to months
Findings in Guillain-Barr syndrome include a(n) _____ (elevated/low/normal) cerebrospinal fluid protein level with a(n) ______ (elevated/low/normal) cell count.
What causes Guillain-Barr syndrome?
An autoimmune attack on the myelin sheath due to molecular mimicry with a precipitating infection
What is the prognosis for patients with Guillain-Barr syndrome?
Almost never fatal, with most patients making a full recovery
How is Guillan-Barr treated?
Respiratory support is critical during paralysis; plasmapheresis and intravenous immune globulins are given
In Guillan-Barr syndrome, what tissue is the target of autoimmune attack?
Which gastrointestinal bacterial infection is a common inciting event for Guillain-Barr syndrome?
Which rapidly progressive disease is characterized by demyelination of the central nervous system due to destruction of oligodendrocytes in AIDS patients?
Progressive multifocal leukoencephalopathy
Which virus has been implicated in progressive multifocal leukoencephalopathy?
JC virus; almost all individuals have evidence of infection, but the virus is latent except in severely immunocompromised patients
In what percentage of AIDS patients is PML seen?
Which demyelinating disease may occur after infections with chickenpox or measles, or with rabies and smallpox vaccinations?
Acute disseminated (postinfectious) encephalomyelitis
Which demyelinating disease is characterized by multifocal perivenular inflammation and demyelination?
Acute disseminated (postinfectious) encephalomyelitis
What is the mode of inheritance of metachromatic leukodystrophy?
In metachromatic leukodystrophy, what is the consequence of sulfatide accumulation in cells?
Impaired production of the myelin sheath
In metachromatic leukodystrophy, which enzyme is deficient?
Which group of hereditary nerve disorders is characterized by defective production of proteins involved in the structure and function of peripheral nerves or the myelin sheath?
How do partial seizures differ from generalized seizures?
Partial seizures affect one area of the brain and are often preceded by an aura; generalized seizures affect the brain diffusely
How do complex and simple partial seizures differ?
Simple partial seizures do not impair consciousness, but can have motor, sensory, autonomic, or psychic effects; complex partial seizures impair consciousness
Name five possible causes of new-onset seizures in the elderly.
Stroke, tumor, trauma, infection, or metabolic abnormalities
From which part of the brain do partial seizures most commonly originate?
Mesial temporal lobe
What is epilepsy?
A disorder of recurrent unprovoked seizures
How does neuronal firing differ in seizure activity compared to normal function?
Firing is synchronized and high-frequency during a seizure
What are common causes of seizures in children?
Genetic disorders, fever (febrile seizures), trauma, congenital malformations, and metabolic insults
A young girl sometimes lapses into a blank stare and then resumes her conversation as if nothing had happened. What kind of seizure may this child be experiencing?
What type of seizure is characterized by quick, repetitive jerks?
What are common causes of seizures among adults?
Tumors, trauma, stroke, and infection
A spouse calls 911 and reports that her husband is on the floor thrashing with alternating stiffening movements. What kind of seizure might the patient be experiencing?
Tonic-clonic (grand mal) seizure
What type of seizure is associated with stiffening (as opposed to jerking)?
A 55-year-old woman presents to the emergency room with a seizure in which she first noted repetitive twitching of her left hand and left side of her mouth. Over 30 seconds, this twitching extended to her left shoulder and was followed by left thigh twitching. What is the most likely location of her seizure?
Right frontal lobe
Drop seizures are also called _____ seizures.
Atonic; atonic seizures can be confused with syncope
What are some physiological causes of headaches?
Irritation of dura, cranial nerves, and extracranial structures; brain parenchyma itself has no sensory receptors
A patient experiences 72 hours of unilateral pulsating pain accompanied by nausea and photophobia; which type of headache does he have?
Which disturbances may be associated with the aura preceding a migraine headache?
Visual, sensory and speech disturbances
Which cranial nerve is irritated in the etiology of migraine headaches?
The release of which three substances may be implicated in the etiology of migraine headaches?
Substance P, CGRP, vasoactive peptides
Which headache is characterized by at least 30 minutes of bilateral steady pain without aura?
Light and noise can aggravate _____ (migraine/tension/both) headaches.
_____ headaches are repetitive brief headaches characterized by unilateral periorbital pain and autonomic symptoms.
Which type of headache is more common in males than females?
Cluster headache may manifest with _____ (ipsilateral/contralateral) lacrimation, rhinorrhea and Horner's syndrome.
A patient presents with the sudden onset of the worst headache of his life. What etiology is suggested by his complaint?
Which concerning pathologies may present as headaches?
Meningitis, hydrocephalus, neoplasia, arteritis
A 49-year-old man presents with 2 weeks of excruciating, periorbital, left-sided head/face pain. The pain lasts 45 minutes and is succeeded by a dull ache that lasts hours. He admits to tearing and redness of the left eye and his wife says that his eye droops when he is in pain. The pain usually occurs twice a night at about the same time. He is afebrile with a normal exam when in the office. What is the most likely diagnosis?
What is vertigo?
The illusion of movement
Which is more common: peripheral or central vertigo?
Name three common etiologies for peripheral vertigo.
Semicircular canal debris, vestibular nerve infection, or Meniere's disease
A patient undergoes positional testing for vertigo and is found to have delayed horizontal nystagmus; what type of vertigo does she have?
Central vertigo is the result of a lesion in what parts of the brain?
Brain stem or cerebellum
A patient undergoes positional testing and is found to have immediate nystagmus that switches directions. He has _____ (peripheral/central) vertigo.
What syndrome is a congenital disorder characterized by facial port-wine stains and ipsilateral leptomeningeal angioma?
A toddler is diagnosed with seizures, mental retardation, and glaucoma. Her pediatrician notices a port-wine stain on the face and hemiparesis. What is the most likely diagnosis?
A toddler is diagnosed with seizures, mental retardation, and glaucoma. Her pediatrician notices a port-wine stain on the face and hemiparesis. What is the associated brain lesion?
Tuberous sclerosis is characterized by what three characteristic cutaneous manifestations?
Ash leaf spots, shagreen patch, and sebaceous adenomas
In addition to its cutaneous manifestations, tuberous sclerosis is characterized by which findings?
Hamartomas in the central nervous system, cardiac rhabdomyoma, renal angiomyolipoma, subependymal giant cell astrocytoma, mental retardation, and seizures
Name five manifestations of neurofibromatosis type 1 (von Recklinghausen's disease).
Caf au lait spots, neurofibromas in the skin, Lisch nodules, optic gliomas, pheochromocytomas
What mutation causes neurofibromatosis type 1 (von Recklinghausen's disease)?
Mutation of the NF-1 gene on chromosome 17
What mutation causes von Hippel-Lindau disease?
Mutation of the tumor suppressor gene VHL on chromosome 3
What is the inheritance pattern of von Hippel-Lindau disease?
What neurocutaneous disorder is associated with cavernous hemangiomas in skin, mucosa, and internal organs; renal cell carcinoma; and hemangioblastoma in retina, brain stem, and cerebellum?
von Hippel-Lindau disease
What is the inheritance pattern of tuberous sclerosis?
The majority of primary brain tumors in adults are _____ (infratentorial/supratentorial), whereas they are mostly _____ (infratentorial/supratentorial) in children.
What percentage of adult brain tumors are metastases? Where are they usually found in the brain?
50%; metastases appear as multiple well-circumscribed lesions at the gray-white junction
List the three most common primary brain tumors in order of prevalence.
Most to least common: glioblastoma multiforme, meningioma, schwannoma
Meningiomas arise from what cell type?
Intracranial schwannomas typically affect what cranial nerve?
Cranial nerve VIII
What are the histologic findings on biopsy of an oligodendroglioma?
Fried egg cells (ie, round nuclei with clear cytoplasm) and a chicken-wire capillary pattern
Most pituitary adenomas originate in the anterior pituitary, which is embryologically derived from what structure?
Rathke's pouch, which develops from nonneural ectoderm
What highly malignant primitive neuroectodermal tumor can compress the fourth ventricle and cause hydrocephalus in children?
What is the prognosis for a child diagnosed with an ependymoma?
What benign childhood tumor is often confused with a pituitary adenoma because it can present with bitemporal hemianopia?
What type of staining may help confirm the diagnosis of glioblastoma multiforme?
Glial fibrillary acidic protein staining (GFAP)
Bilateral schwannomas are typically found in patients with what congenital illness?
Neurofibromatosis type 2
Pilocytic astrocytomas are associated with what histologic findings?
Rosenthal fibers, which are eosinophilic corkscrew fibers
Psammoma bodies are commonly found in what type of primary brain tumor?
What rare and slow-growing primary brain tumor is most often found in the frontal lobes?
Pituitary adenomas most commonly secrete what hormone?
What is the prognosis for a pilocytic astrocytoma?
Good; this is a benign, resectable tumor
What primary brain tumor of childhood is most commonly found in the fourth ventricle?
Perivascular pseudorosettes are characteristic of what primary brain tumor?
A craniopharyngioma is embryologically derived from the remnants of what structure?
What type of brain tumor is characterized by rosettes or a perivascular pseudorosette pattern of cells?
True or False? Medulloblastomas are radiosensitive.
Hemangioblastomas are most often found in what region of the brain?
The histopathologic appearance of which brain tumor shows foamy cells and high vascularity?
Which brain tumor may produce erythropoietin and lead to secondary polycythemia?
What are three common presenting symptoms of a brain tumor?
Seizures, dementia, and focal neurologic deficits
What is the most common childhood supratentorial tumor?
What is the prognosis for glioblastoma multiforme?
The prognosis is typically grave
_____ bodies are laminated calcifications that may be found in a meningioma on histopathology.
_____ (Meningiomas/Schwannomas/Both) are resectable tumors.
Both are resectable
Hemangioblastomas are associated with which genetic disease that arises from a mutation on the third chromosome?
von Hippel-Lindau disease
Which primary brain tumor is typically found in the cerebral hemispheres and may cross the corpus callosum?
Tooth enamel-like calcification is common in what primary brain tumor?
Describe the histologic appearance of glioblastoma multiforme.
Pseudopalisading pleomorphic tumor cells which border central areas of necrosis and hemorrhage
Pilocytic astrocytoma will stain positive for what protein marker?
Spindle cells in a whorled pattern with psammoma bodies are characteristic of which primary intracranial tumor?
A cingulate herniation under the falx cerebri may compress which artery?
The anterior cerebral artery
How does cerebral herniation cause coma and death?
By compressing the brain stem
In which part of the brain is the uncus found?
The medial temporal lobe
Which structure can herniate through the foramen magnum as a result of increased intracranial pressure?
The cerebellar tonsils
Which cranial nerve is most likely to become stretched due to uncal herniation? What symptoms result?
Cranial nerve III; ipsilateral dilated pupil and ptosis
With uncal herniation, which artery is most likely to become compressed? What symptom can result?
The ipsilateral posterior cerebral artery; contralateral homonymous hemianopia
What type of hemorrhages may result from the caudal displacement of the brain stem due to an uncal herniation? Which artery is ruptured?
Duret hemorrhages from paramedian artery rupture
During uncal herniation, ipsilateral paresis may result from damage to what structure?
Contralateral crus cerebri
Name four brain lesions that are ring-enhancing on imaging.
Metastases, abscesses, toxoplasmosis, AIDS lymphoma
Name three uniformly enhancing lesions.
Lymphoma, meningioma, metastases (usually ring enhancing)
Name a heterogeneously enhancing lesion.