Neuromuscular and Brain Dysfunction

Infections: encephalitis - etiology + symptoms

• inflammation of brain tissue

• caused by bacteria, viruses, measles, mumps + chicken pox

• Symptoms include headache, fever, stiff neck and back, progress to lethargy, confusion or even coma

• risk factors: young kids and older adults (above 40)

Infections: encephalitis (diagnosis + testing)

• diagnosis: examining CSF obtained via LP

• treatment: supportive. Severe cases can leave patients with neuro deficits.

-early diagnosis and treatment is best to avoid permanent

infections: meningitis - etiology

• inflammation of meninges (membranes of brain + spinal cord)

• Variety of causes including bacterial, viral, fungal, and toxins such as lead and arsenic

• Most common cause is Neisseria meningitides

• Viral meningitis resolves on its own in about 10 days

• risk factor: young kids and older adults (above 40)

infections: meningitis- symptoms

• onset of a high fever, severe headache, photophobia (fear of light),

stiffness in the neck that resists bending the neck forward or sideways (nuchal rigidity)

• progression of disease: drowsiness, stupor, seizures, and coma

infections: meningitis- diagnosis + testing

• examination of CSF obtained via Lumbar puncture

• antibiotics if bacterial (start empiric therapy then adjust with Culture and sensitivity results)

• Can lead to permanent neuro damage such as hearing loss, learning and developmental issues (pediatric patients), and epilepsy

Brudzinski vs Kernig sign (used to display signs of meninges infection)

• flexion of the hips and knees in response to neck flexion

• resistance to extension of leg in response while hip is flexed

• however lumbar puncture is needed to confirm diagnosis

meningoencephalitis

• inflammation of both the brain tissue and meninges

Cerebrovascular accident (CVA) stroke: causes

• lack of blood flow to brain causing brain tissue death

• Three causes for lack of blood flow: ischemic vs hemorrhagic

• Cerebral thrombus – clot in a brain artery. Symptoms

are gradual (ischemic)

• Cerebral embolism – a small piece of clot breaks off

and travels in a vessel until it gets lodged and occludes

the vessel. Symptoms usually appear quite suddenly.(ischemic)

• Cerebral hemorrhage – the rupture of an artery in the

brain, usually due to either HTN or arteriosclerosis. Symptoms are very sudden.

(hemorrhagic)

ischemic stroke: symptoms

• numbness/weakness often in one side of the body

• confusion

• vision issues

• loss of coordination/balance

• severe headache

• nausea

hemorrhagic stroke: symptoms

• severe headache at back of head

• numbness/weakness mostly on one side of the body

• vision changes’

• loss of consciousness may occur

• loss of coordination/balance

symptoms of both ischemic vs hemorrhagic stroke

• sudden weakness/numbness on one side of the body

• confusion

• headaches

• seizures

CVA diagnosis + treatment

• confirmed by H&P, CT or MRI

• Indicator of the location of brain damage is shown by the pattern

  of hemiparesis (weakness on one side of the body), if present

  − Hemiparesis affecting the left side of the body indicates right-

  sided brain injury and vice versa

• Treatment of CVA – anticoagulants (control clot formation),clot buster therapy, and antihypertensive meds (to lower BP), rehab/PT/OT/speech therapy

transient ischemic attacks-etiology

• sudden, mild mini stroke attacks

• temporary interruption of blood flow to the brain that

  causes neurological symptoms like a CVA but typically resolve

  within 24 hours

• vessel narrowing by atherosclerotic plaque

• warning sign of a CVA

transient ischemic attacks: symptoms, diagnosis, treatment

• symptoms are like CVA but resolve within 24 hours (does not cause permanent damage but is a stroke indicator)

• diagnosis: check BP (HTN), auscultate neck veins (check for

  blood flow irregularities – bruits), arteriogram, CT scan

• Treatment: surgery to open/bypass blocked vessels, carotid

  endarterectomy (CEA) surgical procedure to open carotid vessel

Dementia: alzheimer’s disease: what it is + etiology

• form of dementia characterized by death of neurons and replacement of these neurons by microscopic amyloid plaques and neurofibrillary tangles

• AD is a progressive, irreversible brain disorder, most common cause of dementia of 65 yrs+

• Etiology is unknown, age is the greatest risk factor

Stages of alzheimers (3)

1. Symptoms begin with mild mental impairment characterized by loss of short-term memory, inability to concentrate, personality changes

2. patient struggles with communication skills

3. become restless, disoriented, incontinent, hostile, combative, and totally

dependent on a caregiver.

4. death is usually by secondary cause

Dementia: alzheimer’s disease: diagnosis

• diagnosis cannot officially be made until brain autopsy

• based on symptoms diagnosis can be made after ruling out other brain disorders

• final stages of the disease, CT or MRI may reveal the characteristic brain atrophy and microscopic amyloid plaques

what are amyloid plaques?

• made up of beta-amyloid proteins.

• Beta-amyloid is a small piece of a larger protein called amyloid precursor protein (APP)

• APP is normally found in the body, but when beta-amyloid builds up it causes brain issues

comparision of healthy brain vs alzheimers brain

• compared to a healthy brain, AD brain has fewer synapses/neurons

• AD disrupts neurons ability to repair itself

Brain shrinkage in AD in early stage

• brain naturally shrinks as we age, however more neurons die from AD, causing significant shrinkage

• cell damage usually starts in the hippocampus and entorhinal cortex (in temporal lobe) , key parts for memory

• hippocampus helps form new memories, but it’s less involved in keeping older ones. (many with AD can remember things years ago and forget the day memory)

Brain shrinkage in AD in last stages

• damage moves to the cerebral cortex, which is the area in charge of reasoning, behavior and language (AD patients forget old memories)

• loss of brain activity/tissue is significantly seen in last stage via MRI

Trauma: Epidural and Subdural Hematomas (where it happens)

• epidural hematoma: blood filling in above dura mater (between skull and dura)

• subdural hematoma: blood filling in below dura mater (between dura and arachnoid)

• subdural hematomas occur twice as much (older and anti-clotting meds)

Epidural and Subdural Hematomas-etiology

• epidural: blow to the head as obtained in a fight or accident

• Blood vessels are ruptured and hemorrhage

• Subdural hematoma: result of the head hitting a stationary object as in

a fall

• develops more slower, blood fills up between dura and arachnoid

Trauma: Epidural and Subdural Hematomas symptoms

epidural: within few hours after injury

• headache, dilated pupils, n/v, dizziness

• hematoma grows, the patient may lose consciousness and develop intracranial pressure

• -subdural: usually more chronic (develop slowly/gradual and present as personality changes/confusion)

• hemiparesis, n/v, dizziness, convulsions, loss of

  consciousness

Trauma: Epidural and Subdural Hematomas: diagnosis + treatment

• diagnosis: H&P, x-ray, CT or MRI scan

• treatment: decreasing ICP (if not treated can be fatal)

• special craniotomy called burr holes to drain

blood and cauterization (used to stop bleeding) (small holes drilled into skull)