MBB EXAM 3

seizures, anti seizure medications, headaches, MS, TMJ, neuroinfectious diseases

Seizure

hyperexcitable, excessively synchronous electrical activity of cortical neurons resulting in change of behavior or subjective experience

Provoked seizure

seizures caused by triggers

provoked seizure

seizure due to fever, hyponatremia, head injury, stroke, or meningitis would be an example of:

Unprovoked seizure

seizures may have remote cause

unprovoked seizure

seizure after stroke 2 years ago would be an example of:

Focal seizure

initial activation of seizure limited to a one region of the brain

Generalized seizure

initial activation involves neural network in both hemispheres

Generalized seizures

typically results in loss of consciousness and full body convulsions

Aware focal seizure

a type of seizure where the person remains conscious during the episode

Unaware focal seizure

a type of seizure where the person is not conscious during the episode, often resulting in automatism.

tonic

seizure with stiffening

Clonic

seizure with rhythmic jerking

Myoclonic

seizure with rapid ISOLATED jerk

Atonic

seizure with sudden loss of muscle tone

Generalized tonic-clonic

seizure characterized by both stiffening and jerking phases, typical manifestation of gerneralized seizure

Frontal lobe seizure

seizure presents with contralateral clonic movements, tonic posturing, or atonia, origin?

Parietal lobe seizure

seizure presents with somatosensory changes (e.g. tingling),origin?

Temporal lobe seizure

seizure presents with smell (e.g. burning), taste (e.g. metallic), emotion (e.g. fear), or visceral sensations (“rising”), origin?

Temporal lobe seizure

seizure presents with dissociation/deja vu and blank staring, origin?

Occipital lobe seizure

seizure presents with flashing lights and visual hallucinations/distortions, origin?

Status epilepticus

continuous seizure activity that is abnormally prolonged (≥5 min)

risk for brain damage (potentially longer term)

Why is status epilepticus a medical emergency?

benzodiazepines (lorazepam, diazepam, midazolam)

First-line treatment for if a patient is seizing for OVER 5 MIN (STATUS EPILEPTICUS)

benzodiazepines

increase GABA activity, first line for status epilepticus

Aura

 brief stereotypic prodrome (“warning”) that precedes the more obvious clinical seizure by seconds to minutes

aura (ex: rubber smell)

Implies focal onset of seizure (seizure orgin)

Postictal state

residual neurologic dysfunction following seizure

Automatism

semi-purposeful repetitive “automatic” behaviors during a seizure while consciousness is impaired

Epilepsy

neurological disorder characterized by predisposition for seizures

2+ unprovoked seizures (separated by 24 hrs) or single seizure (w/ 60% recurrence risk)

epilepsy diagnosis criteria 

Abnormal excitation and excessive synchronization

Cause of seizure

Glutamate and aspartate

Main EXCITATORY neurotransmitters involved in a seizure

GABA and glycine

Main inhibitory neurotransmitters involved in a seizure

Alcohol withdraw, hyponatremia, hypoxic-ischemic injury

Conditions that can lower seizure threshold (increase likelihood of seizure)

Alcohol withdraw seizure

seizure due to loss of chronic GABA stimulation

Hyponatremia seizure

seizure due to decrease in intercellular space due to low sodium

Hypoxic-ischemic injury (e.g. stroke, drowning, birth injury) seizure

seizure due to extracellular accumulation of glutamate

Inhibition loss, synaptic function changes, intrinsic excitability (decreased hyperpolarizing current), increase synchronization (gliosis) 

Potential mechanisms of EPILEPTOGENESIS (epilepsy development)

Epileptogenesis

sequence of events that converts a normal neural network into an abnormally hyperexcitable and hypersynchronous one

EEG

can detect or confirm seizures by measuring electrical activity in the brain

Neuroimaging (MRI)

Identifies structural abnormalities that might cause seizures

Decrease excitatory and increase inhibitory signaling

How do antiseizure medications work?

Focal seizure originating in the frontal lobe

A woman has uncontrollable rhythmic left leg jerking, what is the seizure type /origin?

Focal seizure originating in the temporal lobe

A man feels an aura of intense fear, associated with a rising sensation in his chest, then loses awareness and has a generalized seizure, what is the seizure type /origin?

absence seizure generalized 

A child is playing, then suddenly stops and stares blankly for several seconds, then resumes playing as if nothing had happened, what is the seizure type /origin?

inhibit ion channels (Na and Ca) or decrease glutamate activity 

How are excitatory signals dampened by anti seizure meds

glutamate

What neurotransmitter activates EXCITATORY pathways?

Na and Ca

What electrolytes are important for excitatory pathway signaling? 

GABA

What neurotransmitter activates INHIBITORY pathways?

inhibit excitatory and excite inhibitory

What is the desired effect of antiseizure medications on inhibitory and excitatory pathways?

Carbamazepine and oxcarbazepine

block voltage-gated Na channels

Valproic acid

blocks voltage-gated Na channels, and enhances GABA activity

Gabapentin

blocks pre-synaptic calcium channels

Lamotrigine

inhibits voltage gated Na channels, some GABA potentiation

Topiramate

inhibits voltage-gated Na channels, decreases glutamate activity, enhances GABA effects, weak carbonic anhydrase inhibitor

Levetiracetam

decreases glutamate activity and inhibits Ca channels 

Lacosamide

enhances slow inactivation of Na channels (extends hyperpolarization period)

Lamotrigine 

first-line therapy for FOCAL seizures

valproic acid, carbamazepine, levetiracetam (val can’t levitate)

first-line therapies for generalized tonic-clonic seizures

valproic acid

 first-line therapy for myoclonic seizures

ethosuximide or valproic acid

first-line therapy for ABSENCE seizures

Lamotrigine, Oxcarbazepine, Valproic acid

Antisiezure medications that may BENEFIT patients with DEPRESSION

Valproic acid, gabapentin

Antiseizure medications that may BENEFIT patients with ANXIETY

Gabapentin, levetiracetam, topiramate

Antiseizure medications that may BENEFIT patients with MIGRAINE

Topiramate and levetiracetam

Antiseizure medications that may WORSEN DEPRESSION/ANXIETY

Carbamazepine, oxcarbazepine, lamotrigine, lacosamide, phenytoin

drugs with adverse reaction of cutaneous rash (SJS/TEN)

stevens johnson syndrome (SJS)

a patient has been taking lamotigine and develops a blistering rash, most likely diagnosis?

lacosamide and lamotrigine

anti seizure meds with Cardiac rhythm disturbances

Carbamazepine and oxcarbazepine

anti seizures drugs that may cause HYPONATREMIA 

Carbamazepine and Valproic acid

antiseizure medication with great potential for DDIs

tension

Most common type of headache

migraine

Most common headache seen by medical professionals

Primary headache

a headache not caused by another medical condition

tension, migraine, and cluster 

main types of PRIMARY headaches 

Secondary headache

a headache caused by an underlying medical condition such as injury, infection, or tumor

secondary

Headache associated with malignancy or infection would be what type of headache

migraine

pulsating headache with light and sound sensitivity, nausea, and vomiting

systemic symptoms, neurologic symptoms, onset (sudden), other conditions (ex: head trauma), postion affects severity

what does SNOOP criteria for headache red flags stand for?

first/worst headache, thunderclap, fever, papilledema (w/ focal neurologic signs), reduced consciousness, hx of acute glaucoma

Headache features that require EMERGENT evaluation

Papilledema w/o focal signs, reduced consciousness in elderly, temporal arteritis signs

Headache features that required URGENT evaluation

ICHD-3

Online resource to help with headache diagnosis

calcitonin gene-related peptide (CGRP)

neuropeptide released from trigeminal sensory nerve endings during a MIGRAINE attack; target of a new generation of migraine treatments

migraine 

moderate-severe UNILATERAL PULSING headache aggravated by exercising

4-72 hours

duration of MIGRAINE

tension-type 

mild-moderate bilaterate pressure headache, ACTIVITY does NOT WORSEN

30min-7 days

duration of TENSION-type headache

cluster

EXTREMELY SEVERE unilateral orbital/supraorbital/temporal headache at predictable times (usually NIGHTIME) (circadian rhythm key) w/ same side autonomic symptoms (nasal congestion, tearing, eyelid edema ect. )

15-180 min 

duration of cluster headache

cluster

which type of headache most commonly presents with Ipsilateral tearing, nasal congestion, ptosis , mios sis, and eyelid edema

secondary headache 

pregnant patient presents with pressure heaache that “feel like a band around head”. patient is having trouble sleeping and the headache has gradually worsened over. the past two weeks. the headache is worse when she coughs, strains, or bends down. most likely diagnosis?

migraine w/o aura

Patient presents with 3-4 severe, debilitating headaches per month over two years. Pain: Deep ache; throbbing when severe. HAs last 1-2 days; located at right temple >> bilaterally; associated with runny nose and nasal congestion. Associated with nausea, light sensitivity. No auras. No neurologic features. DIAGNOSIS?

cluster headache 

patient presents with DISABLING left eye PAIN that lasts 90 minutes at a time. NO light or sound sensitivity, nor nausea or vomiting. There are no vision changes with the headache. The headache attacks occur EVERY NIGHT. DIAGNOSIS?

tension-type headache

Patient presents with mild, pressure-like pain located on both sides of head. NO light or sound sensitivity, nor nausea or vomiting. NO associated autonomic features (tearing of the eyes, nasal congestion, or runny nose). The headache can last up to 3 days. DIAGNOSIS?

Headaches, seizures, focal neurological deficits, cognitive/personality changes, and increased intracranial pressure

how do brain tumors present?

secondary

Which type of headache would be cause for concern

morning headaches with nausea, worse when laying flat/bending over, increased frequency/severity, onset after 40

What  characteristics of a headache would raise concern for brain tumor (red flags)

Glioblastoma multiforme

most AGGRESIVE and COMMON type of MALIGNANT primary brain tumor in ADULTS?

poor (12-15 mo survival) 

What is the general prognosis for GLIOBASTOMA tumors?

Meningioma

most common PRIMARY CNS TUMOR overall?

dura (arachnoid cells)

From what part of the CNS do MENINGIOMAS (most common CNS tumor)  arise?