Nervous System

Flashcards covering key neurological conditions, diagnostic tests, symptoms, and treatments from the lecture notes.

Which populations are at the highest risk for acute bacterial meningitis?

Neonates, infants, and older patients.

What are the two most common pathogens causing community-acquired bacterial meningitis?

Streptococcus pneumoniae (50%) and Neisseria meningitidis (30%).

What are the classic symptoms of acute bacterial meningitis?

Acute onset of high fever, severe headache, stiff neck (nuchal rigidity) with altered mental status, and potentially purple petechial rashes.

What are the two main classifications of acute stroke and their approximate incidence percentages?

Ischemic (about 80%) and hemorrhagic (20%).

How does an ischemic stroke typically present?

Acute onset of stuttering/speech disturbance, one-sided facial weakness, and one-sided weakness of the arms and/or legs (hemiparesis), often with a thunderclap-type acute headache.

What is a common characteristic of patients with hemorrhagic stroke, and how do they often present?

Poorly controlled hypertension; they present with abrupt onset of severe headache, nausea/vomiting, and nuchal rigidity (subarachnoid hemorrhage).

What is a chronic subdural hematoma (SDH), and how does it typically present?

Bleeding between the dura and subarachnoid membranes; it presents gradually with symptoms like headaches and gradual cognitive impairment (apathy, somnolence, confusion) a few weeks after head trauma.

Which populations are more prone to chronic subdural hematoma?

Those with alcohol use disorder, older adults, and those on anticoagulation or aspirin therapy.

List characteristic signs of a 'dangerous headache' warranting urgent evaluation.

Thunderclap headache, 'worst headache of my life,' first onset at age 50 or older, sudden onset after coughing/exertion/straining/sex, sudden change in LOC, focal neurologic signs, or headache with papilledema.

What is Giant Cell Arteritis (GCA), and what are its key symptoms?

A systemic inflammatory disorder of medium and large arteries (vasculitis); symptoms include new headache or change in preexisting headache (often unilateral temporal pain), abrupt visual disturbances, jaw claudication, unexplained fever, and an indurated, reddened, cord-like temporal artery that is tender and warm.

What laboratory findings are markedly elevated but nonspecific for Giant Cell Arteritis?

Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP).

What condition is associated with Giant Cell Arteritis, occurring in approximately 40% to 50% of patients?

Polymyalgia rheumatica (PMR).

What is the critical complication of untreated Giant Cell Arteritis?

Permanent blindness.

What are the classic presenting symptoms of Multiple Sclerosis in an adult female patient?

Episodic visual loss or diplopia, problems with balance and walking, numbness and paresthesia on one side of the face, accompanied by urinary incontinence and/or bowel dysfunction. The Lhermitte sign (electric shock sensation down the back on neck flexion) may also be present.

What defines a Subarachnoid Hemorrhage (SAH) and its classic headache description?

Bleeding into the subarachnoid space and CSF. It is characterized by sudden and rapid onset of severe headache described as 'the worst headache of my life.'

What are the accompanying symptoms of Subarachnoid Hemorrhage?

Nausea/vomiting, neck pain or stiffness (positive Brudzinski and/or Kernig signs), photophobia, visual changes, and a rapid decline in level of consciousness.

What is a 'sentinel headache' in the context of SAH?

A sudden intense headache that can precede a spontaneous SAH by days to weeks.

What is the initial imaging study of choice to detect SAH within the first 24 hours?

An non-contrast CT scan.

What general areas are assessed in a neurologic exam?

Mental status, cranial nerves, and motor, reflex, and sensory examination.

What function does the cerebellum coordinate?

Unconscious regulation of balance, muscle tone, and voluntary movements.

How is cerebellar gait ataxia described?

A wide-based staggering gait.

What does a positive 'tandem gait' test indicate?

The patient is unable to walk a straight line with one foot in front of the other, loses balance, and falls.

What is dysdiadochokinesia?

Difficulty performing rapid alternating movements (e.g., pronation and supination of hands on thighs).

What does a positive 'finger-to-nose' or 'finger-to-finger' test, also known as dysmetria, indicate?

The patient is unable to touch or misses touching their nose and/or the examiner's finger accurately.

What is the Romberg test designed to assess?

Proprioception (the sense of body position) and balance; a positive test suggests cerebellar ataxia/dysfunction or sensory loss when the patient cannot remain steady with eyes closed.

What mnemonic can be used to remember the names of the Cranial Nerves in order?

'On Old Olympus Towering Tops, A Finn And German Viewed Some Hops.' (Olfactory, Optic, Oculomotor, Trochlear, Trigeminal, Abducens, Facial, Acoustic, Glossopharyngeal, Vagus, Spinal Accessory, Hypoglossal).

What mnemonic helps remember the function (sensory, motor, or both) of each Cranial Nerve?

'Some Say Marry Money, But My Brother Says Big Brains Matter Most.' (S=Sensory, M=Motor, B=Both).

How is Cranial Nerve I (Olfactory) typically tested?

By using a familiar scent (e.g., coffee, peppermint) and blocking one nostril at a time.

How is Central Distance Vision tested for Cranial Nerve II (Optic)?

Using a Snellen chart with the patient standing 20 feet away.

What three cranial nerves are usually tested together to control extraocular muscles (EOM)?

CN III (Oculomotor), CN IV (Trochlear), and CN VI (Abducens).

What major functions are controlled by Cranial Nerve V (Trigeminal)?

Muscles of mastication and sensory nerves to the face, scalp, cornea, mucous membranes, and nose.

What is Bell's Palsy caused by, and which cranial nerve is affected?

Inflammation of the motor portion of the facial nerve (CN VII), leading to unilateral facial paralysis.

How is Cranial Nerve IX (Glossopharyngeal) and X (Vagus) typically tested?

By telling the patient to open their mouth and yawn, observing for uvula midline symmetry, and checking the gag reflex.

What does Cranial Nerve XI (Spinal Accessory) control?

Shoulder shrug and head rotation.

Which cranial nerve controls tongue movement?

CN XII (Hypoglossal).

What is monofilament testing used for in the sensory system?

To assess nerve sensation, particularly in diabetic peripheral neuropathy, by bending a filament on the plantar and dorsal surfaces of the foot.

What does a positive result in sensory system testing (monofilament, sharp-dull, temperature, vibration) indicate?

Inability to feel the monofilament, discriminate sensations, or sense vibration; vibration sense is often the earliest affected in peripheral neuropathy.

What is stereognosis?

The ability to recognize familiar objects through the sense of touch only, with eyes closed.

What is graphesthesia?

The ability to identify figures 'written' on the skin (e.g., palm) with eyes closed.

What is the pronator drift test, and what does a positive result suggest?

The patient stretches arms with palms up and closes eyes; a positive result is one arm drifting downward, suggesting upper motor neuron diseases (e.g., stroke, ALS).

What are the signs of lower motor neuron lesions?

Muscle weakness, muscle wasting/atrophy, and fasciculations.

How are deep tendon reflexes graded?

0 (no response), 1+ (low response), 2+ (normal), 3+ (brisker than average), and 4+ (very brisk/sustained clonus).

What is the reflex center for the quadriceps reflex (knee-jerk response)?

L2 to L4.

What is the reflex center for the Achilles reflex (ankle-jerk response)?

L5 to S2 (tibial nerve).

What is a positive Babinski's sign in adults, and what does it indicate?

Toes spread like a fan when the plantar surface of the foot is stroked; in adults, it is an abnormal finding, while it is normal in young infants.

What does acute onset of cerebellar ataxia represent medically?

A medical emergency, potentially an acute vascular event, requiring neuroimaging and screening for causative drugs/toxins.

What neurologic maneuvers are used to assess for meningeal irritation?

Kernig's Sign, Brudzinski's Sign, and Nuchal Rigidity.

How is Kernig's Sign tested, and what indicates a positive result?

Flexing the patient's hip then attempting to straighten the leg; positive if resistance due to painful hamstrings or back pain.

How is Brudzinski's Sign tested, and what indicates a positive result?

Passively flexing the patient's neck toward the chest; positive if the patient reflexively flexes the hips and knees.

What is a positive finding for nuchal rigidity?

Inability to touch the chest with the chin due to pain.

What are the common pathogens for bacterial meningitis in adults?

Streptococcus pneumoniae, N. meningitidis, and Haemophilus influenzae.

What is the classic presentation of bacterial meningitis?

Acute onset of fever >100.4°F (38°C), severe headache, stiff neck (nuchal rigidity), and rapid changes in mental status and LOC (confusion, lethargy, stupor).

When is a CT scan of the head performed before a lumbar puncture in suspected bacterial meningitis?

In patients with risk factors like papilledema, focal neurologic deficit, abnormal LOC, new-onset seizure, history of CNS disease, or immunocompromise.

What are the characteristic CSF findings in bacterial meningitis?

Large numbers of WBCs (cloudy CSF), elevated protein, and low glucose levels, with bacteria isolated in culture.

What is the empiric antibiotic treatment for bacterial meningitis in adults, especially those over 50?

Third-generation IV cephalosporin (e.g., cefotaxime/ceftriaxone) PLUS vancomycin PLUS ampicillin (for adults >50 years), along with dexamethasone.

What are the early symptoms of acute mild traumatic brain injury (concussion)?

Confusion, headache, dizziness or vertigo, poor balance, and nausea and vomiting; most do not lose consciousness.

How is mild TBI defined by the Glasgow Coma Scale (GCS)?

A GCS score of 13 to 15 (measured 30 minutes after injury).

What are the indications for hospital admission after a head trauma?

GCS score <15, seizures or other neurologic deficit(s), recurrent vomiting, abnormal head CT, or abnormal bleeding.

What is the cause of Bell's Palsy, and what are its characteristic symptoms?

Dysfunction of the motor branch of the facial nerve (CN VII), causing abrupt onset of unilateral facial paralysis, difficulty chewing/swallowing, and inability to fully close the eyelid on the affected side, with intact skin sensation.

What is the first-line treatment for Bell's Palsy?

Early treatment with high-dose oral glucocorticoids (prednisone 60–80 mg/day for 1 week), potentially coadministered with antiviral therapy (valacyclovir or acyclovir) for severe cases.

What is Carpal Tunnel Syndrome (CTS)?

Compression of the median nerve as it travels through the carpal tunnel.

What are the classic symptoms of Carpal Tunnel Syndrome?

Gradual onset of numbness and tingling (paresthesia) in the median nerve territory (thumb, index finger, middle finger), weaker hand grip, and symptoms worsened by repetitive actions or at night.

How is Tinel's sign elicited for diagnosing Carpal Tunnel Syndrome?

Tapping over the anterior wrist (carpal tunnel), which elicits 'pins and needles' or tingling in the median nerve distribution.

How is Phalen's sign elicited, and what does a positive result indicate?

Engaging in full wrist flexion for 60 seconds; a positive sign is numbness or tingling sensation of the median nerve over the hand.

What are the major modifiable risk factors for ischemic stroke?

Hypertension, dyslipidemia, diabetes, smoking, and physical inactivity.

What are major risk factors for hemorrhagic strokes?

Older age, hypertension, cigarette smoking, family history, alcohol use, sympathomimetic drug use, and use of antithrombotic therapy.

How does an embolic stroke typically present?

Abrupt onset of difficulty speaking, unilateral hemiparesis, and weakness of the arms or legs (or both).

What mnemonic is used to recognize stroke symptoms, and what does each letter stand for?

FAST: F-Face drooping, A-Arm weakness, S-Speech difficulty, T-Time to call 911.

What is the initial imaging study in the ED for suspected stroke?

CT scan (without contrast).

What is the time window for IV thrombolytic therapy with alteplase for acute ischemic stroke?

Within 4.5 hours of symptom onset.

What is a common visual field loss complication of stroke?

Homonymous hemianopia (visual field loss involving either the two left halves or the two right halves).

What is Broca's aphasia?

Also known as 'expressive aphasia,' where the patient comprehends speech but has extreme difficulty with the motor aspects of speech; speech length is usually less than four words.

What is Wernicke's aphasia?

Also known as 'receptive aphasia,' where the patient has difficulty with comprehension but no problem with producing speech.

What is the definitive diagnostic test for Giant Cell Arteritis?

Temporal artery biopsy.

What is the initial treatment for Giant Cell Arteritis?

High-dose systemic glucocorticoids (e.g., prednisone 40–60 mg PO daily) to preserve vision.

What are the symptoms of a migraine without aura?

Throbbing pain behind one eye, photophobia, phonophobia, and nausea/vomiting.

What are the typical symptoms of Trigeminal Neuralgia?

Intense, very brief, sudden, usually unilateral sharp stabbing pain in one or more branches of CN V (trigeminal).

What are the characteristic symptoms of a Cluster Headache?

Severe 'ice-pick' piercing pain behind one eye, with tearing, eye redness, rhinorrhea, ptosis, and miosis on one side (Horner's syndrome).

Which headache type is more common in middle-aged males and occurs in clusters?

Cluster Headache.

What describes a Tension-Type Headache?

Bilateral 'band-like' pain, vise-like or tight in quality, continuous dull pain usually generalized, lasting several hours, possibly with trapezius muscle spasms.

What is a Medication Overuse Headache (Rebound Headache)?

Headache occurring 15 or more days per month due to overuse of acute headache medications for more than 3 months.

What is Lhermitte sign, often seen in Multiple Sclerosis?

An electric shock-like sensation running down the back when bending the neck forward/flexion.

What is the imaging test of choice for Multiple Sclerosis lesions?

MRI of the brain and spinal cord.

What are the key signs and symptoms of Polymyalgia Rheumatica (PMR)?

Bilateral joint stiffness and aching (lasting 30 minutes or longer, especially mornings) in the posterior neck, shoulders, upper arms, and hips (pelvic girdle), with severe morning stiffness (gel phenomenon).

What characterizes an episode of a Cluster Headache?

Abrupt onset of recurrent 'ice-pick,' severe, lacerating periorbital pain along with autonomic symptoms like tearing and clear nasal discharge (rhinitis), and sometimes drooping eyelid (ptosis).

What is the acute treatment for Cluster Headaches?

High-dose oxygen (100% at 12 L/min by mask for 15 minutes) and/or triptans (sumatriptan, zolmitriptan).

What is the prophylactic treatment of choice for frequent Cluster Headache attacks?

The calcium channel blocker verapamil.

What are the four phases of a migraine attack?

Prodrome, aura, headache, and postdrome.

What nonpharmacologic interventions are recommended for migraines?

Acupuncture, rest in a quiet/darkened room, ice pack, ginger ale or cola for nausea, aerobic exercise, transcutaneous electrical nerve stimulation, and avoiding precipitating foods/activities.

What medications are used for mild-to-moderate migraine attacks?

Analgesics (acetaminophen or NSAIDs alone or in combination), often with an antiemetic.

What medications are used for moderate-to-severe migraine attacks, and what are their contraindications?

Oral triptans or sumatriptan–NSAID combination, or non-oral triptans with antiemetics. Contraindicated in ischemic heart disease, Prinzmetal’s angina, ischemic stroke, uncontrolled hypertension, hemiplegic/basilar migraine, and pregnancy.

Which drugs are used for migraine prophylaxis?

Beta-blockers (propranolol, metoprolol), CCBs (verapamil, nifedipine), ACE inhibitors/ARBs (lisinopril, candesartan), TCAs (amitriptyline), SNRIs (venlafaxine), and anticonvulsants (valproate, topiramate, gabapentin).

What is the primary characteristic that distinguishes a tension-type headache from most other headaches?

It is typically bilateral, non-throbbing, and of mild to moderate intensity.

What is the common acute treatment for tension-type headaches?

NSAIDs (naproxen, ibuprofen, aspirin) or acetaminophen; combination drugs with caffeine are an option.

What are generalized tonic-clonic seizures?

Also called grand mal seizures, they involve abrupt loss of consciousness, stiff extremities (tonic phase), followed by rhythmic jerking (clonic phase), and potential tongue biting.

What characterize absence seizures?

Common in childhood, usually lasting 5-10 seconds, and marked by behavioral arrest ('petit mal').

Which diagnostic tests are essential for epileptic seizure diagnosis?

Electroencephalogram (EEG) and MRI (preferred over CT for detecting causes), along with blood tests for electrolytes, glucose, etc.

When should antiseizure medication be initiated for seizures?

In patients with two or more unprovoked seizures.

What are common triggers or precipitating factors for seizures to be avoided?

Sleep deprivation, alcohol use, infection, and certain medications.

What is a Transient Ischemic Attack (TIA)?

A transient episode of neurologic dysfunction caused by focal ischemia (brain, spinal cord, or retinal) without acute infarction of the brain, serving as a major stroke warning sign.