Unit 3: CNS Flashcards
Meningitis
Inflammation of the meninges
Viral (–> lymphocyte exudate into subarachnoid space) or bacterial (—> neutrophil exudate -pus- into subarachnoid space)
May lead to thrombosis, CSF blockage, increased intracranial pressure
Meningitis: Sx
Headache, neck stiffness, fever
Irritability, confusion, lethargy
Kernig’s sign (pain with hip flexion and knee extension)
Brudzinski’s sign (cervical flexion causes hip and knee flexion)
Most common cause of bacterial meningitis in adults
streptococcus pneumonia
Most common cause of bacterial meningitis in neonates
Group B strep
Encephalitis
Inflammation of the brain parynchyma
Localized or diffuse
Primary viral (in US most often HSV1) -- direct viral invasion of brain Also acute disseminated encephalomyelitis (autoimmune Type 2 ) 1-3 weeks after infection -- multifocal demyelination
Encephalitis: Sx
Meningeal signs
Seizures, focal neurological defects, personality changes
Possible GI or respiratory prodrome
May result in paralysis, weakness, movement disorders
Brain abscess
Uncommon
Expanding focal infections that act as space-occupying lesions (headache, focal neurological Sx, increased intracranial pressure)
Glioma
Most common primary brain tumour
Malignant
Astrocytes (80%), oligodendrocytes, ependymal cells
Astrocytomas – 80% infiltritive
The most common infiltritive astrocytoma is glioblastoma, making it the most common CNS tumour
Glioblastoma Multiforme
Grade 4 astrocytoma
Most common and most aggressive primary brain cancer
Meningioma
Mostly benign tumour of the meninges
2nd most common intracranial tumour
Amyotrophic Lateral Sclerosis
ALS. Lou Gehrig’s Disease
Loss and sclerosing of motor neurons in spinal cord, midbrain, and then cerebral cortex. Especially affects lateral cerebrospinal pathway.
Characterized by motor weakness and progressive wasting
Idiopathic (occasionally familial). Rare
Alzheimers
Common
Buildup of beta-amayloid plaque, tau proteins, in brain causing inflammation and destruction, primarily in frontal and temporal lobes.
Memory loss, clinical presentation of demential
4th leading cause of death in the elderly
Vascular dementia
Multiple small infarcts over time leading to widespread neural damage
Abulia
Lack of motivation
Lewy Body Dementia
Dementia caused by Lewy’s bodies, which are pathogenic aggregates of proteins which develop inside nerve cells.
Associated with Parkinson’s Disease. Appear within a year of motor symptoms
Increased sleep, disorganized speech, hallucinations
Multiple Sclerosis
Autoimmune demyelination, especially
Oligodendrocytes.
Atrophy of white matter
Progressive; relapse/remission patterns
MS: Sx
Often begins with sensory changes
Weakness spasticity
Pain dizziness
Brainstem Sx
Four patterns of MS course
Relapse-Remitting (most common)
Primary progressive
Secondary progressive
Progressive relapsing
Chorea
Brief, semi-directed, irregular movements
Irregular, migrating contractions
Atherosis
Involuntary convoluted, writhing movements of fingers, arms, legs, neck.
Choreoathetosis
Combination of chorea and athetosis
Seen in Huntingtons, among other paths
Dystonia
Increased muscle tone and spasm, often accompanied by writhing movements
Parkinson’s disease
Destruction of dopamine this neurons in substantia nigra
Common
Increased inhibition of movement, decreased facilitation of movement
Parkinson’s: Sx
Extrapyramidal type symptoms
Resting tremor
Rigidity
Bradykinesia/akinesia
Mask-like expression
Huntington’s
Huntington disease is an autosomal dominant disorder characterized by chorea, neuropsychiatric symptoms, and progressive cognitive deterioration, usually beginning during middle age.
Atrophy of caudate nucleus
Huntington’s: Sx
Chorea
Dysarthria
Neuropsychiatric symptoms (personality change, poor executive function, mood changes)
Ischemic stroke
Linked to hypertension and atherosclerotic disease
Thrombosis, embolism, hypofusion
Hemorrhagic stroke
Worst headache ever
Seizures LO
Often subarachnoid bleed from ruptured aneurysm or vascular malformation
High mortality rate
Middle cerebral artery stroke
Hemiplegia
Hemianaesthesia
Broca’s aphasia
Anterior cerebral artery stroke
CL hemiparesis
Lower extremity sensory loss
Cerebral palsy
Perinatal brain damage
Usually caused by hypoxia, ischemia, or trauma to cerebral blood vessels
Four categories of Cerebral Palsy
1 spastic
2 athetoid
3 ataxic
4 mixed (usually 1+2)
Fredrick’s ataxia
Friedreich’s ataxia is an autosomal recessive inherited disease that causes progressive damage to the nervous system, especially sensory neurons necessary for proper limb movement.
It manifests in initial symptoms of poor coordination such as gait disturbance; it can also lead to scoliosis, heart disease and diabetes, but does not affect cognitive function. The disease progresses until a wheelchair is required for mobility. Its incidence in the general population is roughly 1 in 50,000.
Spinal muscular atrophy
Weakness and wasting due to progressive anterior horn degeneration.
Atrophy, hypotonia, weakness, fatigue
Often fatal restrictive lung disease.
Paresis
Weakness
Central cord syndrome
Damage to centre of spinal cord, periphery unaffected
Hyperextension injury to c-spine
Motor/sensory impairment to Upper
Limbs; lower limbs less affected.
Brown-sequard syndrome
Damage to one side of the spinal cord
Trauma (stabbing, shooting)
IL: loss of motor function, proprioception, vibration, 2 point
Discrimination
CL: loss of pain and temperature perception
Anterior cord syndrome
Direct trauma, hyperflexion
Damage to corticospinal and spinothalamic tracts
BL loss of motor function, pain and temp, crude touch
Breathing affects if spinal lesion above
C5
Poliomyelitis
Viral
Destruction of motor cells; sensory intact
Asymptomatic
Non-paralytic
Paralytic
Usually full recovery
Postpoliomyelitis
In patients who have had paralytic poliomyelitis, muscle fatigue and decreased endurance, often accompanied by weakness, fasciculations, and atrophy, may develop years or decades later, particularly in older patients and in patients who are severely affected initially. Damage usually occurs in previously affected muscle groups. However, postpoliomyelitis syndrome rarely increases disability substantially.
The cause may be related to further loss of anterior horn cells due to aging in a population of neurons already depleted by earlier poliovirus infectio
Upper motor neuron lesion
CNS
Corticospinal or pyramidal tracts
Loss of voluntary movement Hemi/para/quadriplegia Spasticity Hyperreflexia Clonus
Lower motor neuron lesion
Affects nerves between anterior spinal horn and muscle
Flacid paralysis Paresis Fasciculations Hypotonia Hyporeflexia
Neuropraxia
Nerve injury
Complete recovery with removal of compression
Axonotmesis
Disruption of Myelin sheath bun axon intact
Wallerian degeneration
Neuronotmesis
Damage to sheath and axon body
Wallerian degeneration
Hyperkinetic disorder
Hyperkinetic disorder is a psychiatric syndrome emerging in early childhood that features an enduring pattern of severe, developmentally inappropriate inattention, hyperactivity and impulsivity across different settings (e.g., home and school) that significantly impair academic, social and work performance.
Extreme ADHD, combined type
Hyperkinesia
an increase in muscular activity that can result in excessive abnormal movements, excessive normal movements, or a combination of both
Basal ganglia damage
Hypokinesia
Partial or complete loss of
Muscle movement
Basal ganglia damage
Neuropathy
Damage, pathology involving PNS
Neuralgia
Pain along nerve path
Neuritis
Inflammation of nerve
Radiculopathy
Damage to nerve root
Plexopathy
Damage to nerve plexus
Herpes zoster
Shingles
Post herpetic neuralgia
Ramsey Hunt Syndrome
Shingles of the facial nerve
Neuralgia
Possible hearing loss and facial paralysis
