Chapter 5 Flashcards
1
Q
The nervous system is comprised of which two basic systems? What organs are included in both?
A
- CNS- brain and spinal cord
2. PNS- nerves that connest CNS with sensory receptors, muscles
2
Q
What is the typical anatomy of a neuron?
A
cell body, which dendrites spead off of, a long spine called axons, moves down to synapses which are specialized junctions that connect to other neurons.
3
Q
What is myelin?
A
a white fatty substance that is wrapped around thee axon of the nerve cell to protect it and help with the conduction of nerve impulses.
4
Q
What is the difference between axons with white matter and grey matter?
A
White matter is axons that have myelin protection, and those that are not covered in myelin are called grey matter.
5
Q
The brain can be divided into what 3 regions?
A
- forebrain: cerebral cortext
- midbrain: connects spinal cords with the forebrain and forms the major part of brainstem
- hindbrain: medulla oblongata, cerebellum.
6
Q
What is the responsibility of the sensory roots and motor roots in the spinal cord?
A
- convey messages from the body to the brain,
2. covey messages from the brain to the rest of the body, (skeletal muscles)
7
Q
Define the difference between gray and white matter in the spinal cord?
A
inner core of spinal cord is the gray matter, outer layer is the white matter.
The white matter carries columns of sensory fibres and motor fibres
8
Q
Define the physiology of the PNS (ie. what nerve categories are there)
A
PNS- are nerves outside the brain or spinal cord.
- comprised of 12 cranial nerves
- 31 pairs of spinal nerves,
9
Q
The PNS is split into two main separate sxs. Name and define them.
A
- Somatic Nervous system: the nerves that connect the brain and spinal cord with skeletal muscles under voluntary control. Also connect sensory organs with the brain, including skin receptors
- Autonomic Nervous system:
connecta brain and spinal cord with internal organs that process within the body not under voluntary control .
10
Q
There are two parts of the autonomic nervous system of the PNS. Name and define them
A
- sympathetic nervous system: prepares body for flight/fright
- parasympathetic nervous system: maintains internal status quo
11
Q
Name different diagnostic investigations methods for neurological disorders. (13)
A
- observation
- history (personal/Fx)
- physical examination
- MRI
- CT
- MRA
- CTA
- Cerebral angiography
9, PET - lumbar puncture
- Evoked response test
- EEG
- Nerve conduction studies
12
Q
If a neurological disorder is suspected a physical examination will be conducted. Which tests are preformed on the pt at this time?
A
reflexes, sensation, motor movement, coordination, gait, and stance as well as for the internal body system regulated by ANS.
They will also question the cpt’s mental status by asking basic questions.
13
Q
What are the most common neurological sxs and signs?
A
- pain- headache/neck pain
- muscle problems-
- sensory problems
- altered consciousness - seizures/faiting/dizziness/confussion
14
Q
What imaging test is best used for diagnosing MS, brain tumors and strokes? why?
A
MRI, - d/t ability to provide detailed images of body parts surrounded by bone.
15
Q
What is fMRI?
A
functional MRI, (new), measured metabolic changes in the brain. Helps identify areas of the brain for specific processes.
16
Q
for which neurological disorder would you use a CT imaging scan?
A
Hydrocephalus to brain tumors.
Clearer images of skull and spin than MRI, and detects bleeding.
17
Q
Which imaging technique is best used to look at blood vessels withint the body, such as in the brain, head and heart and lungs?
Hint: it can also be used to identify atherosclerosis wihtin the carotid arteries, small aneurysms and arteriovenous malformations.
A
MRA-
18
Q
What is a CTA and what would a CT angiography be used for?
A
like a CT but with contract material
blood vessels in the body, and images of calcium deposits in blood vesles.
CTA exposes pt to radiation but has clearer imaging than MRA
19
Q
What imaging does a cerebral angiography provide ?
A
image of blood vessels and circulation in the brain
- contrast is used, and highlights these ares
- picture is VERY details.
20
Q
What is a PET?
A
produces 3D images.
Metabolic imaging procedure that uses radioactive substance (tracer) in the body which is absorbed at different rates for different types of tissues. Hotspots are tumors and they’re brighter than normal tissue.
21
Q
What is a Lumbar puncture?
A
A needle is inserted into the spinal canal to extract CSF from the subarachnoid space.
- detects: tumors, infection, injury, bleeding within brain/spinal. It can also measure the pressure of the fluid which can indicate tumors, bleeding and venous thrombosis
22
Q
What is an Evoked response test?
A
measures electrical activity in the brain in response to stimulation by sound, sight or touch. the electric activity is measured by EEG
23
Q
There are 3 types of Evoked response tests. Name them
A
- BAER- meausures hearing ability.
- VER- dx optic nerve problems
- SSER- dx problems with the spinal cord, as well as numbness or weakness of extremities.
24
Q
What is an EEG, and when is it used?
A
Measured abN acitvities in the brain
dx seizures and evaluating brain damage caused by stroke or brain injury
25
When would you want to preform an EMG? (electromyography)
assess and record the electrical activity of muscles, both at rest and during contraction.
- usually used in conjunction wiht nerve conduction study to dx disorders of muscles, peripheral nerves or neuromuscular junctions.
26
What is a Nerve conduction study?
measures the speed of conduction of nerve impulses in both sensory and motor nerves.
Dx muscle weakness as a result of nerve disorder ie. CTS (carpal tunnel syndrome)
27
carotoid stenosis arises as a result of what?
generalize atherosclerotic disease and sig causes TIAs and stokes.
28
How is carotid artery stenosis dx'ed?
Asxs: dx with detection of a carotid bruit on physical examination
dx confirmed by non-invasive techniques such as carotid duplex u/w, MRA, or CTA
29
How is carotid artery stenosis tx'ed
reducing co-existing cardiovascular risk factors, or by the use of anti-platelet drug, or by carotid endaterectomy, if severe
30
What are the most common sxs for a cerebrovascular accident and TIA
changes in vision/speech
| decreased movement or senstion, or changes in the level of consciousness
31
What is the definition of a stroke?
the clinic syndrome of rapid onset of focal cerebral deficit, lasting more than 24 hours or leading to death with no apparent cause other than a vascular one.
32
What are the two main pathological types of stokes?
1. primary ischemic stroke
| 2. primary intracerebral hemorrhage
33
What are the 3 causes of an ischemic stroke?
1. atherosclerosis
2. blood clot that forms in the brain (thrombus)
3. blood clot or piece of athromatous plaque or other material that travels to the brain from another location.
34
Does occlusion of the artery develop quickly or slowly?
slowly, arteries in the brain are large in diameter and can be blocked up to 75% and still provide adequate blood supply.
35
Ischemic strokes usually develop in the presence of atherosclerosis when what happens?
a small thrombus, often from disease in teh carotid arteries develops and becomes lodged in one of the smaller cerebral vesels.
36
Stokes caused by embolism are most common due to what?
cardiogenic emboli, ie clots that develop secondary to heart disorders such as valve defects or arrhythmia. On set is sudden severe neurological deficit. ITs worse if the blood vessel ruptures and blood leaks out
37
What areas of the brain are included in the vertebrobasilar system?
medulla, cerebellum, midbrain
20% of ischemic stokes occur in this system
38
What are the sxs of Vertebrobasilar strokes?
1. cerebella signs
2. dysarthria and dysphagia
3. Vertigo, nausea, and vomiting.
39
Name 4 causes of a primary intracerebral hemmorhage
1. as a result of HTN,
2. when a blood vessel affect by disease burst
3. when a blood vessel blocked by an embolism burst
4. AVM or aneurysm ruptures.
40
A hematoma of greater than 30 mm is associated with what?
a poor prognosis
an increased pulse pressure
reduced glasgow coma score
41
What are the sxs/residuals of a stoke in the R hemisphere of the brain?
```
L sided paralysis,
spatial and perceptual difficulties
judgement difficulties
behaviour style changes (impulse)
memory impaired,
```
42
What are the sxs/residuals of a stroke in the L hemisphere of the brain?
R sided paralysis
aphasia, (speech/language problems) but can be
unimpaired when it comes to writing, reading or understanding speech.
- slow and cautious behaviour changes
- memory impairments./
43
What is the tx for a stroke?
no cure, but tx the thrombolytic sxs with clot busting drugs (tPA), and rehabilitation based on sxs.
- surgery can done to remove blood or clots from the brain, to repair hemorrhage sports.
44
What is a TIA, ie when does it occur?
when blood supply to the brian is only breifly interrupted.
sometimes known as minor stoke, but sxs <24 hrs.
45
What are the sxs/residuals of a TIA?
leaves no permanent deficits, usually as a warning sign for increased risk of a more serious cerebrovascular event
46
What are the underwriting considerations for a TIA and stoke?
1. age at time of event
2. time elapsed since episode
3. persisting neurological defects
4. underlying cause
5. HTN BP <140/90
6. presence of co-existing factors.
47
Define subarachnoid hemorrhage.
indicates the presence of blood within the subarachnoid space, as a results of the rupture of an intracranial aneurysm, AVM, hematomas (trauma bleed)
48
What causes an intracranial aneurysm?
1. caused by the weakening of a blood vessel wall, causing bulging and potential rupture.
49
Define an ateriovenous malformation ( AVM)
congenital abN in the development of the vasculature of the brain and/or spinal cord- its a tangle of arteries and veins with abN connections between the two called fistulas.
50
What are the sxs of a subarachnoid hemorrhage?
1. sudden onset of severe headache
2. nausea and vomiting
3. photophobia
4. possible loss of consciousness or convulsions
5. possible neurological sxs-
51
How is a subarachnoid hemorrhage dxed?
CT- followed by a cerebral angiogram to identify the cause and precise location of the bleed, and if aneurysmal, whether there are other aneurysms present.
52
What is the tx for a subarachnoid hemorrhage?
depends on site and size,
clipping- most common
endovascular coiling- newer and better prognosis
53
What are the factors to consider when underwriting for a subarachnoid hemorrhage?
1. severity of the initial episode
2. results of investigations and treatment
3. presence of absence of continuing neurological sxs/epilepsy
4. control of co-existing risk factors
54
IS MS genetically linked?
it has both a genetic and environmental implication on increased risk development.
55
MS can be classified into a variety of subtypes. what are they?
1. relapsing-remiting form- characteries by exacerbations followed by remissions.
2. Secondary progressive form- characterized by insidious neurological deterioration, with or without superimposed relapses- leads to disability.
3. primary progressive- characterized by progression from onset, usually without any superimposed relapses.
56
What causes CIS (clinically isolated syndrome)
lasts >24 hrs, and is likely caused by inflammation of the myeling sheath of the nerve in one or more sites in the CNS
57
What are the sxs of MS?
loss of sensation in the arms or legs, or a tingling or pins and needles in the affected area.
- can also affect the nerve that controls eye movement, causing blurred or double vision.
>> SXS vary from person to person
58
What is optic neuritis?
- close relation to MS
| - characterized by loss of vision, dyschromatopsia, and eye pain
59
How is MS dx'ed?
combination of clinical sxs and MRI-
MRI typically shows areas of high signal, (white mater) especially in the peri-ventricular region or spinal cord.
There needs to be two attacks that are disseminated in time and space.
60
# Define the clinical requirements/ definition for the following diagnosis
1. multiple sclerosis
2. probable multiple sclerosis
3. possible multiple sclerosis –
4. not multiple sclerosis –
1. – There is evidence of dissemination of time and space, as well as clinical and paraclinical evidence to support a diagnosis of multiple sclerosis.
2. – Clinical and paraclinical evidence is strongly suggestive of multiple sclerosis, but maybe the MRI is clear, or only shows one lesion, i.e. there is no evidence of dissemination in time and/or space.
3. Symptoms are similar to those seen in multiple sclerosis, but the paraclinical evidence does not yet support this diagnosis. Additionally, alternate diagnoses cannot be held responsible for the symptoms.
4. Symptoms are able to be attributed to a cause other than multiple sclerosis.
61
What is the tx for MS?
no cure- disease-modifying drugs can reduce the number and severity of relapses or slow the rate of progression.
Physio and reflexology can be helpful in alleviating sxs.
62
What are some side effects with the tx options for MS?>
beta-interferons can produce flu-like sxs and fatigue
monoclonal antibodies and oral tx cause reactions, headaches, nausea and diarrhea
severe side effects: bradycardia, ^ LFT and idiopathic thrombocytopenia
63
How is disability in MS measured?
using the expanded disability status scale, which was developed in 1983. It ranges from 0-10. Scoring is based on examination by neurologist.
64
What are some considerations you should take when u/w MS?
1. definiet dx?
2. age of onset
3. subtype of MS
4. date of last attack
5. frequently of attacks
6. current level of disability
65
What is epilepsy?
a group of chronic disorders in which there is a tendency towards recurrent unprovoked and unpredictable seizures.
Ie. two or more unprovoked seizures.
66
What is a seizure?
an episodic disturbance of movement, feeling, or consicousness caused by sudden synchronous inappropriate and excessive electrical discharges in the cerebral cortex.
67
What are the major causes of epilepsy?
1. brain tumors
2. arteriovenous malformations
3. Stroke.
68
What can increase the risk of epilepsy by 10 times?
1. head injury with concussion plus 1 of:
- loss of consciousness >30 mins
- loss of memory after the injury
- neurological adbnormalities
- Skull fracture
2. CNS infections
3. cerebral palsy with mental handicap
4. febrile sizures that are long, and only involve one side of the body
5. ETOH abuse
69
Seizures can be either focal or generalized at onset. What does focal mean?
its confined to a localized are of the brain, This includes the following kinds
1. simple seizures ( temporal lobe, psychomotor, jacksonian siezure)- no loss of conciousnes
2. complex partial seizures, including focal seizures, that become generalized.
70
Define Generalized seizures
An abN elevtrical activity that is spread thorughout the brain. They are developmental in origin- ie and anomaly arises that predisposes the individual to sezures
71
Name the different kinds of generalized seizures
1, grand mal- any age
2. Absence seizures (petit mal)- childhood, characterized by altered consciousness (absence) can occur upto 100x a day unnoticed (atypical absence seizures)
3. other generalize (ie myoclonic seizures.
72
How is Epilepsy treated
drug therapy
1. carbamazepine
2. phenobarbitol
3. valproic acid
4. phenytoin
50% con't to experience sxs
73
What information should be considered by an underwriter when evaluating the risk of seizures?
1. type of epilepsy
2. results of investigations
3. frequency of attacks
4. date of last attack
5. type and level of tx
6. compliance with tx
7. occupational hx
74
Why are Intracraniel tumors considered to be malignancy?
1. invasion of local tissue- however they rarely metastasize to outside the brain
2. they dont fit the normal definition
3. they are rare
4. bening tumors do occur, they are slow and rarely spread to invade local tissue
75
How are most intracranial tumors treated (meningiomas and acoustic neuromas)?
how are medulloblastomas treated?
how are germ cell tumors treated?
how is lymphoma in the CNS treated?
1. surgery, unless it is located in a vital area.
2. radiotehrapy
3. radiotherapy and/or chemo
4. chemo.
76
Majority of Brain tumors arise from glial cells- thus known as gliomas. They are categorized into 4 groups based on malignancy. Name these groups
1. grade 1- pilocytic astrocytoma
2. grade 2- low-grade astrocytoma
3. Grade 3- anaplastic astrocytoma
4. Grade 4- gluoblastoma multiforme
77
```
Which out of the following have a more favourable prognosis and which have a less favourable prognosis?
Meningioma
Astrocytoma
Glioma
Acoustic neuroma
Pinealoma
medulloblastoma
Neuroblastoma
sarcoma
```
More:
Meningioma
Acoustic neuroma
Pinealoma
```
Less:
medulloblastoma
Neuroblastoma
sarcoma
Astrocytoma
Glioma
```
78
What information should be ask/considered by an underwriting when assessing the risk of intracranial tumors?
1. precise histology
2. results of investigations
3. tx given
4. time since dx and completion of tx
5. any residual neurological or psychological impairment
79
What is an hemiplegic migraine?
a migraine where sxs including sudden onset of unilateral weakness, or even loss of speech or consciousness.
- rare
80
What are some concerning causes of headaches?
1. AVM or ruptured cerebral artery aneurysm
2. tumors and temporal arteritis
3. inflammation of the arteries supplying the scalp.
4. cervical disc disease can radiate neck pain to headaches sxs.
81
What should an underwriter consider when underwriting the risk of headaches
1. type of headache
2. results of investigations
3. tx
4. any hx of neurological sxs
82
What is Encephalitis?
inflammation of the brain, usually d/t viral infection, but can also be bacterial, parasitic or fungal.
common causes:
1. herpes virus infection
2. common childhood illness
3. insect-born viruses.
83
What are the sxs of encephalitis?
1. severe headaches
2. sudden onset of fever
3. photophobia
4. stiff neck
5. nausea and vomiting
6. drowsiness and confusion
7. seizures
84
What is the treatment for encephalitis?
rest and pain reflief including anti-inflammatories.
occasionally anti-viral drugs can be administered.
85
What is meningitis?
Inflammation of the meninges, the membranes that surround the brain and the spinal cord.
Cause by virus or bacterial
86
Which has a better prognosis bacterial or viral meningitis?
Viral.
87
What are the symptoms of meningitis?
1. severe headaches
2. high fever
3. photophobia
4. stiff neck
5. nausea and vomiting
6. drowsiness and confusion
7. rash- in some cases
8. seizures
88
What is the treatment for bacterial and viral meningitis?
bacterial: abx IV
viral: rest and pain relief.
89
What should an underwriter consider when underwriting the risk for a history of encephalitits and meningitis?
1. cause of infection
2. results of investigations
3. details of tx given
4. details of ongoing/ neurological complications
90
Define hydrocephalus
Accumulation of cerebrospinal fluid within the skull. This causes ventricles to swell, compressing the normal brain tissue.
91
What are some causes of hydrocephalus?
1. congenital malformation (spinal bifida)
2. infection
3. injury to brain
92
What are the treatment options for hydrocephalus?
relive the increased intracranial pressure- may require a shunt which can lead to blockage and investion. - revisions and or replacements are common.
93
What should an underwriter consider when assessing the risk of hydrocephalus?
1. underlying cause
2. type of treatment and response to tx
3. if a shunt is in place- are there complications
4. whether there are residual problems as a result of the hydrocephalus
94
Individuals who suffer a stoke are at risk for what additional 5 disabilities post 6 months ?
1. depressive sxs
2. inability to walk unassisted
3. social disability
4. institutionalization
5. bladder incontinence
95
What scale is widely used to measure functional independence and is considered a "core metril" in stroke assessment?
Modified ranking scale,
| - scored 0-6 based on disability sxs. 0 being none at all, and 6 being dead.
96
What does the Barhel Index (BI scale) measure?
```
measured self-care and physical dependency, a score of 100 is considered normal,. BI <40 is severe dependance. Activities are listed below and are scored 0,5,10
feeding
bathing
grooming
dressing
bowels
bladder
toilet use
transfers (bed to chair)
mobitily (on level surface)
stairs
```
