ch 26 - Neurological Disorders

left off on slide 15

what are the parts of a neurological exam?

patient history and physical exam

what is important about the patient history part of a neurological exam?

gather info about the patient and their family. Also observe behaviors while taking the history to assess mental status, motor control, and speech abnormalities.

what kinds of cognitive tests can a neurologist perform?

basic (such as memory and attention)

what types of assessment can be part of a neurological physical exam?

cranial nerve assessment, variety of assessment tools

after a neurological examination, what kind of follow-up testing can occur?

imaging (EEG, CT, MRI) and a variety of medical tests (including blood, saliva, stool tests)

most common form of injury in people under age 40

traumatic brain injury

20% of all TBI results from

sport activities

in addition to direct damage, TBI can affect brain functioning through…

disrupting blood supply, inducing bleeding, swelling, infection, scarring of the brain (seizures)

how does glucose metabolism change after TBI?

there is a long-term decrease in glucose metabolism

neurological signs of ___-head injuries are highly specific

open-head

what are the coup and countercoup?

in a closed-head injury, the coup is the site of impact and the countercoup is the opposite side.

what forces are at play in a closed head injury?

coup/countercoup

twisting and shearing of white matter fibers

bleeding + pressure

edema

what are the outcomes of closed-head injuries?

coma, behavioral effects

when coma results from a closed-head injury, the duration scales with 

severity of injury

how can closed-head TBI cause behavioral effects?

impairment of specific functions, generalized impairments (inability to concentrate, personality and social effects)

chronic traumatic encephalopathy

common in athletes. progressive brain disorder that results from multiple TBIs and can lead to dementia

CTE causes what pathology on the brain tissue?

tau pathology

what type of assessment is most valuable for a brain injury?

behavioral assessment

Objective indicator of the degree of unconsciousness and recovery of consciousness (eye, motor, verbal)

Glasgow coma scale

explain the scoring of the glasgow coma scale

8 or less = severe injury

9-12 = moderate

13+ = mild

post traumatic amnesia is a measure of

severity of injury

what are seizures?

spontaneous, abnormal discharges of neurons that result from injury, infection, or tumors

epilepsy can be diagnosed after how many seizures?

it can be diagnosed after one, but typically after multiple

symptomatic vs idiopathic seizures

symptomatic - associated with a known cause

idiopathic - spontaneous, without any known cause

what are the three common symptoms related to epilepsy?

aura

loss of consciousness

movement

epilepsy is diagnosed using

EEG

focal seizures

begins in one place and spreads

what are the types of focal seizures?

jacksonian focal seizures, complex partial seizures

what type of seizure is bilaterally symmetrical?

generalized seizures

types of generalized seizures

grand mal and petit mal (absence seizures)

what are the stages of a grand mal seizure

may have an aura

tonic (body stiffens)

clonic (rhythmic shaking)

postseizure/postictal (depression and confusion)

what happens during a petit mal seizure?

loss of awareness, no motor activity except blinking or rolling eyes or turning head.

akinetic seizures and myoclonic seizures are seen mostly in

children

describe akinetic seizures/myoclonic spasms

may collapse suddenly without warning. myoclonic spasms are massive seizures with sudden flexion or extension of entire body.

dissociative seizures

resemble focal seizures, but no EEG changes. patients report feeling cut off from their body and surroundings

Seizure state typically ends without intervention, although ___ can be administered to end the seizure

GABA agonists or glutamate antagonists

treatment for seizures should take place…

within 5 minutes of seizure onset

drugs are used in epilepsy to

inhibit the development of seizures or their propagation

what are diphenylhydantoin and phenobarbital?

anticonvulsant drugs

how can surgery improve treatment of epilepsy?

remove focal site

other than medication and surgery, what other (experimental) treatment is there for epilepsy?

deep brain stimulation

what are brain tumors?

neoplasms that have no physiological function that grow from glia and other support cells

can brain tumors grow from neurons?

no, just glia and other support cells

benign vs malignant brain tumor

benign - not likely to recur after removal

malignant - likely to recur after removal. progressive and life threatening

what is a glioma?

a tumor that grows in brain, below meninges (infiltrating)

45% of brain tumors are

gliomas

what is a meningioma?

a tumor that grows in the meninges (encapsulating)

what is a metastatic tumor?

transferred to brain from other organs (ex. lungs)

what is the treatment for a brain tumor?

surgery (best) and radiation. not chemo

tumor symptoms result from

increased pressure inside the skull

tumor symptoms

headache, vomiting, slowing of heart rate, mental dullness, double visions, and convulsions

where does headache pain come from?

cranial nerves (especially V, IX, X), pain sensors in arteries and dural sinuses.

classic migraine

visual aura from vasoconstriction for 20-40 minutes, then headache onset with vasodilation

what is a scotoma?

a visual field abnormality (or a blind spot) that may occur in migraines

most common neurological disorder

migraine headaches

migraine headache pain is associated with

blood flow returning to normal after

what is the difference between common migraine and classic migraine?

classic has an aura, common does not have a clear aura (but may have a sense of it coming on)

short episodes of unilateral pain in head or face, recurring for weeks

cluster headache

hemiplegic migraine

migraine that results in loss of movement from the limbs unilaterally

ophthalmologic migraine

migraine that results in loss of movement of the eyes

headaches that are symptoms of tumors, head trauma, infection, vascular malformation, or severe hypertension are called

Headaches Associated with Neurological Disease

muscle-contraction (tension) headaches

most common type of headache, felt broadly around the head and neck. results from stress

non-migrainous vascular headaches result from dilation of the ___

cranial arteries (induced by many causes, including fever, anoxia, anemia, and hypoglycemia)

vasomotor rhinitis

headaches that result from over congestion of nasal membranes and sinuses

how are migraines treated?

specific drugs at the time of the attack

ergotamine compounds are sometimes used to treat

migraine

why is caffeine often used in migraine treatment?

it reduces dilation

how are tension headaches treated?

pharmaceutical agents, stress management (behavioral therapy, lifestyle changes)

how do brain infections generally start?

from other parts of the body (e.g., inhaled)

how do infections kill neural cells?

interference with blood supply

disturb glucose/oxygen metabolism

edema

etc

how are brain infections diagnosed?

analyzing cerebrospinal fluid and taking cultures of blood

what are the four types of pathogenic microorganisms that can infect the brain?

viral, bacterial, mycotic infections, and parasitic infections

neurotropic viruses target ___. give examples

CNS cells. examples: polio, rabies

pantropic viruses target ___. give examples

CNS and rest of body. examples: herpes and mumps

west nile virus and Zika virus can cause

viral meningitis

give examples of bacterial brain infections

bacterial meningitis and brain abscesses (can result from HIV)

how do you treat a bacterial brain infection?

antibiotics, drainage of abscesses or spinal tap

what is a mycotic brain infection?

infection caused by a fungus (yeasts, molds, and mushrooms)

which is more severe: viral or bacterial brain infection

viral. difficult to treat, no antidote, can be fatal

how are mycotic infections treated?

no satisfactory treatment, but can be treated with antibiotics

amebiasis dysentery, malaria, and toxoplasmosis (T. gondii) are all

parasitic infections

amebiasis dysentery

infestation of a protozoan amoeba, causes encephalitis and brain abscesses

malaria

transmitted by mosquito bites, produces local hemorrhages and degeneration of neurons

toxoplasmosis (T. gondii)

transmitted from rats through domestic cats to humans

myasthenia gravis

severe muscular fatigue after minor exertion, worse at end of day.

myasthenia gravis results from

insufficient acetylcholine receptors on the muscles due to autoimmune attack

polio (myelitis)

virus that attacks lower motor neurons in the spinal cord. leads to paralysis and muscle wasting

multiple sclerosis

loss of myelin mainly in the motor tracts (and sensory), sclerotic plaques. many proposed causes.

what are sclerotic plaques?

small, hard scars where the myelin sheath has been destroyed

___ treatment seems promising for MS

autoimmune treatment

paraplegia

paralysis of the lower limbs (thoracic)

quadriplegia

paralysis of all four limbs (cervical)

paraplegia and quadriplegia result from

a complete transection of the spinal cord

after an injury that completely transects the spinal cord, how does this affect the transmission of motor and sensory information?

prevents transmission of motor commands down and sensory info up

what are the immediate symptoms of a spinal injury that leads to para/quadriplegia?

loss of movement, sensation, reflexes, thermoregulatory activity, and bladder control. spinal reflexes gradually return.

Brown–Séquard syndrome

one sided spinal injury where some ascending/descending pathways are impacted. pain and temperature sensation is lost contralaterally, fine touch and pressure are lost ipsilaterally.

hemiplegia

damage to cortex and basal ganglia resulting in loss of voluntary movements and changes to reflexes contralaterally.

how is hemiplegia diagnosed?

Babinski sign

what is the typical response to the babinski reflex test?

infants will extend their toes, adults will point their tows downward.

hemiplegia most often occurs in

older results after a stroke