16. Neuro: Disorders of CNS and PNS Flashcards
Most common locations of vertebral injuries
- cervical (1,2,4-7) - T1-L2
bleeding within the brain
intracerebral hematoma
spinal injury due to direct contusion of the spinal cord by bone/disk material in the spinal canal (crushed vertebral body); caused by forced applied at top of head
vertical/axial compression
spinal injury that includes shearing force to the acceleration force and ruptures support ligaments in addition to producing fractures
rotational injury
displacement of the nucleus pulposus or annulus fibrosis beyond the intervertebral disk space -> nucleus pulposus extrudes and compresses nerve roots
herniated intervertebral disk
aneurysm that results from diffuse arteriosclerotic changes and are found most commonly in the basilar arteries or terminal portions of the internal carotid arteries
fusiform (giant) aneurysms
inflammation of the brain and spinal cord; can be viral, fungal, or bacterial
meningitis
mass of dilated vessels between the arterial and venous system without an intervening capillary bed; usually present at birth but symptoms have delayed onset (before 30 y/o)
arteriovenous malformation (AVM)
causes of cerebral infarction
- abrupt vascular occlusion (thrombosis/emboli) - gradual vessel occlusion - partial occlusion of stenotic vessels - may also be hemorrhagic in nature
spinal injury that causes wedge/compression fracture of vertebral body and compresses spinal cord parenchyma or vascular structures
hyperflexion spinal injury
straitening of knee w/ hip and knee flexed produces pain in back and neck regions
Kernig sign
How is myasthenia gravis diagnosed and treated?
AChE inhibitors (Tensilon)
clinical manifestations meningitis
- headache and AMS - phonophobia - photophobia - neck stiffness - high fever - petechial rash (if meningococcal infection)
results when an area of the brain loses its blood supply
cerebral infarction
stroke usually caused by occlusion of a single, deep perforating artery that supplies small penetrating subcortical vessels; will have pure motor or sensory deficits
lacunar stroke
brain injury at the site of impact
coup injury
acquired inflammatory disease causing demyelination of the peripheral nerves w/ relative sparing of axons; acute onset w/ ascending motor paralysis that usually occurs after respiratory or GI infection
Guillain-Barre syndrome
most common type of brain aneurysm that is usually due to congenital abnormalities in the arterial wall; occur in large intracranial vessels and will cause subarachnoid hemorrhage if ruptured
saccular (berry) aneurysms
bleeding between the dura mater and the skull; artery usually source of bleeding and usually accompanied by a skull fracture
epidural hematoma
ballooning and weakening of a blood vessel in the brain
intracranial aneurysm
trauma that penetrates the dura mater; involves compound skull fractures
open brain injury
symptoms of intracranial tumors
- focal deficits depending on location - cerebral edema - IICP sxs (AMS, headache, vomiting, seizures, unsteady gait, loss of sphincter control)
passive flexion of neck produces neck pain and increased rigidity
Brudzinski sign
associated w/ systemic hypo perfusion caused by heart failure, pulmonary embolism, or bleeding that causes inadequate blood supply to the brain
hypoperfusion/hemodynamic stroke
most common causes of autonomic dysreflexia
distended bladder or rectum; also caused by pain receptors in the skin, penis, and uterus
spinal injury that causes dislocation of posterior elements and compression of spinal cord
hyperextension spinal injury
Most common area of the head epidural hematomas are seen
temporal fossa
a mass of blood is formed as bleeding continues into the brain -> adjacent brain tissue is displaced and compressed -> causes ischemia, edema, IICP, and necrosis
hemorrhagic stroke
normal activity of the spinal cord ceases at and below the level of injury due to lack of continuous nervous discharges from the brain; transient
spinal shock
most common cause of spinal cord trauma
vertebral injuries
in autonomic dysreflexia, what parasympathetic response will occur above lesion (4)?
- arterial dilation - flushed skin - headache - sweating
causes of spinal shock
presence of hemorrhage or edema at the spinal cord; also due to transection of the cord which would not be transient
clinical manifestation of spinal shock
complete loss of reflex function (skeletal, bladder, bowel, sexual function, thermal control, and autonomic control) below level of lesion
a process of normal aging as a response to continuous vertical compression of the spine (axial loading)
degenerative disk disease (DDD)
occurs when there is obstruction to arterial blood flow to the brain from thrombus formation, an embolus, or hypo perfusion related to decreased blood volume or heart failure
ischemic stroke
acute febrile illness, usually of viral origin, with nervous system involvement
encephalitis
condition due to a compressed nerve in the spine that can cause pain, numbness, tingling, or weakness along the course of the nerve/dermatome
radiculopathy
involves fragments that break from a thrombus formed outside the brain (usually heart, aorta, or common carotid)
embolic stroke
Blunt trauma to the head can result in what types of brain injuries that can occur at the same time?
focal brain injury and diffuse axonal injury
fracture that opens a communication between cranial contents and the environment -> increased risk of infection
compound skull fracture
where do embolic strokes usually occur?
small brain vessels or bifurcations (narrowing)
escape of blood from a defective or injured vessel into the subarachnoid space; often due to ruptured aneurysms
subarachnoid hemorrhage (SAH)
syndrome of sudden, massive reflex sympathetic discharge associated w/ spinal cord injury at T6 or above where descending inhibition is blocked
autonomic hyperreflexia (dysreflexia)
episode of neurological dysfunction lasting no more than 1 hour and resulting from focal cerebral ischemia
transient ischemic attack (TIA)
chronic autoimmune disease where IgG antibodies are produced against ACh receptors -> block binding of ACh and decrease muscle contraction
myasthenia gravis
in autonomic dysreflexia, stimulation of the sympathetic nervous system will cause what (4)?
- vasoconstriction - hypertension - skin pallor - pilomotor spasms (goosebumps)
symptoms of myasthenia gravis
- weakness and fatigue - ptosis (drooping of eyelid) - diplopia - difficulty chewing
chronic inflammatory disease involving degeneration of CNS myelin, scarring (sclerosis or plaque formation), and loss of axons
multiple sclerosis
Most common causes of encephalitis
- bites from mosquitoes, ticks, or flies - HSV1
bleeding between the dura mater and the brain; vein usually source of bleeding
subdural hematoma
fracture at the base of the skull; pts can leak spinal fluid from their ears/nose and have raccoon eyes
basilar skull fracture
4 types of vertebral injuries
- simple fracture - compressed fracture (wedge; vertebral body compressed anteriorly) - comminuted fracture (vertebral body shattered into several fragments) - dislocation
fracture of the lamina (usually in the lumbar region; L5) and it causes a separation between adjacent vertebrae
spondylolysis
secondary to spondylolysis; anterior displacement (sliding) of the inferior vertebral segment
spondylolisthesis
arise from arterial occlusions caused by thrombi formation in arteries supplying the brain or intracranial vessels
thrombotic stroke
3 types of back pain and what causes them
- muscular: result of spasm in tissue producing ischemia - joint: usually due to osteoarthritis or disease arthritis - fibroskeletal: usually due to fractures/dislocation of ligamentous structures
Explain the cause of autonomic dysreflexia
- sensory receptors below level of cord lesion are stimulated - intact autonomic nervous system reflexively responds -> increase BP (sympathetics) - baroreceptors in cerebral vessels, carotid sinus, and aorta sense HTN and stimulate parasympathetics - HR decreases but vessels don’t dilate because efferent impulses can’t pass through cord
injury from the brain rebounding and hitting opposite side of skull after impact
contrecoup injury
narrowing of the spinal canal that causes pressure on the spinal nerves or cord and can be congenital or acquired (more common); associated w/ trauma and arthritis
spinal stenosis
