Unit 4 - Neurological & sensory disorders Flashcards
Myopia
Excess curvature of the lens causes the image to focus in front of the retina
Hyperopia
An eye lens that is not curved enough causes the image to focus behind the retina
Symptoms of mild otitis media
Itching in the ear canal
Slight redness in the ear canal
Mild discomfort that worsens if the outer ear is pushed or pulled
Clear, odorless drainage
Which type of stroke (CVA) is responsible for 85% of strokes?
Ischemic stroke
Thrombotic stroke
Plaque contributes to development of a blood clot (thrombus),
leading to atherosclerosis that reduces blood flow to the brain.
Types of ischemic stroke
Thrombotic and embolic
Embolic stroke
An embolus forms in a part of the body away from the brain before
traveling and lodging itself into the narrow brain arteries.
Hemorrhagic stroke
A blood vessel leaks or bursts inside the brain, leading to bleeding in the
brain. This can be the result of uncontrolled hypertension, aneurysms, or the rupture of an
abnormality known as an arteriovenous malformation (AVM).
Types of hemorrhagic stroke
Subarachnoid hemorrhage and intracerebral hemorrhage
Intracerebral hemorrhage
Blood spills into the brain tissue as a result of a burst blood
vessel in the brain. Appropriate blood flow is shut off to surrounding cells, which become damaged.
Subarachnoid hemorrhage
Blood spills into the brain tissue due to a ruptured artery,
usually due to a ruptured aneurysm. After the hemorrhage, the blood vessels in the
brain spasm, leading to additional cell damage and reduced blood flow. A sudden,
excruciating headache usually signals a subarachnoid hemorrhage.
What type of stroke often presents with a sudden, excruciating headache?
A subarachnoid hemorrhage
Transient ischemic attack (TIA)
TIAs are known as ministrokes. A temporary blockage reduces
blood flow, leading to stroke-like symptoms. TIAs do not leave permanent symptoms and lasts
less than 5 minutes.
Risk factors for CVA
- Hypertension
- High cholesterol
- Diabetes
- Overweight or obese
- Physically inactive
- Cardiovascular disease
- Obstructive sleep apnea
- Smoking/secondhand smoke
- Heavy or binge drinking
- Illicit drug use
- Use of some birth control pills or hormone replacement therapies that include estrogen
- Advanced age (most over 55).
- Ethnicity - African descent
- Sex - men have more strokes than women but women have strokes later in life and are more likely to die as a result.
- History - personal or family history that includes strokes, heart attacks, or TIAs
Symptoms of a stroke (CVA)
Sudden dizziness Sudden loss of balance Sudden loss of coordination Confusion Slurring of words Difficulty understanding speech Numbness, weakness, or paralysis of the arm, face, or leg, particularly in one side of the body Blurred or blacked-out vision Double vision Headache accompanied with vomiting or altered consciousness
Effects of a CVA
Paralysis Loss of muscle movement and/or control Dysarthria Aphasia Difficulty swallowing or eating Memory loss Difficulty with thinking, making decisions, reasoning, and understanding Loss of control over emotions Depression Pain Numbness or tingling, increased sensitivity to temperature changes Behavioral changes
Tests for CVA
Physical exam: An examination including blood pressure check and use of a stethoscope. An ophthalmoscope can uncover cholesterol crystals or clots at the back of the eyes.
Blood test: Blood clotting time and levels of sugar and chemicals in the blood must be managed as part of stroke treatment.
CT scan: A CT scan can reveal areas of hemorrhage, stroke, or tumors.
MRI: The area of brain damage is assessed with an MRI.
Cerebral angiogram: Arteries and blood vessels in the brain are imaged to find blockages and plaques.
Echocardiogram: can reveal clots that may have traveled from the heart to the brain in cases of embolic stroke.
Treatment for ischemic stroke
Blood flow must be restored to the brain.
- Thrombolytics must begin within 4.5 hours of onset of symptoms. Aspirin may also be given to guard against the
occurrence of another stroke. Other blood-thinning medicines like clopidogrel or warfarin can be given, although usually not in an emergency room. - Tissue plasminogen activator (TPA) can be
given intravenously to break up the clot.
Doctors may also opt to deliver medication directly to the brain through a catheter. A catheter can also aid in clot removal with a tiny mechanical device. A carotid endarterectomy (CEA) or
angioplasty with stents can also be performed to prevent future strokes.
Treatment for hemorrhagic stroke
Controlling bleeding and reducing pressure in the brain
- Drugs to lower intracranial pressure and blood pressure and prevent seizures
- Once bleeding stops, medical care is provided as the body reabsorbs the blood
- Surgical removal may be needed if the area is large or if there is excessive pressure on the brain.
- Treatment of abnormalities in the blood vessels may be required to prevent future CVAs.
Clipping can keep an aneurysm from bursting or bleeding from a previously ruptured aneurysm.
Endovascular embolization (coiling) blocks blood flow to an existing aneurysm. AVM removal is
possible if the AVM isn’t large and is not deep inside the brain.
What does rehabilitation after a stroke include?
Physical therapy, occupational therapy, and
speech therapy may be part of a stroke rehabilitation plan.
What causes migraines?
The exact cause of migraines is not understood. Migraines seem to be associated with
environmental and genetic factors. Changes in the brainstem, particularly interactions with the
trigeminal nerve, can lead to migraines. An imbalance of serotonin may also be associated, as
serotonin levels drop during a migraine headache. The drop causes neuropeptides to travel to
the meninges, triggering a migraine.
Triggers for migraines
Food: chocolate, alcohol (particularly red wine/beer), aged cheeses, aspartame, MSG, salty foods, processed foods, and high amounts of caffeine.
Fasting
Stress
Hormones: when estrogen levels fluctuate before or during their period, or when estrogen levels drop. Hormones associated with pregnancy and menopause. Usually worse during the first trimester and improve as pregnancy progresses.
Sensory stimuli: Loud sounds, strong smells or odors, bright lights, pulsing lights, or glare from the sun
Physical factors: Physical exertion, especially exertion more intense than usual, including sexual activity.
Medication: oral contraceptives and vasodilators.
Changes in sleep patterns: Too much or too little sleep. Jet lag
Environmental changes: Changes in barometric pressure or weather
Which demographic is affected by migraines?
- Migraines occur in people of all ages, with most people experiencing their first migraine during adolescence.
- People with migraines almost always have an attack before age 40.
- Women are three times more likely than men to have migraines. In childhood, boys develop more headaches, but more girls are affected by the onset of puberty.
- Around 90% of people with a family history of migraines will develop migraines.