What are the main side effects of acetazolamide
Hyperammonemia & paresthesia, renal tubular acidosis (hypokalemia), NAGMA
A patient with IIH develops papilledema due to comprehension of what structure?
Optic nerve sheath -> causing congestion and the optic nerve head (site of arterial supply to the eye)
What is the most common demographic for IIH?
Females of childbearing age with obesity
Upper motor neuron lesions cause increased reflexes and this pathologic reflex, while lower motor neuron lesions cause decreased reflexes and visible muscle twitching called this.
Babinski sign (or extensor plantar response) and fasciculations
in terms of homunculus organization, describe the spatial location of sensation for the leg, arm and face
leg: medial
Arm: lateral
Face: most lateral
Triptans are migraine medication used for _______ therapy, and work via ________ agonism, causing vaso_______ of cranial vessels
abortive; 5-HT1B/1D; constriction
Also inhibit trigeminal nerve activation, some CGRP release inhibition
What is the correct order of flow for CSF in the brain? (don't have to get everything, just basic ideas)
Lateral ventricles -> Third ventricle (via intraventricular foramen) -> cerebral aqueduct - >fourth ventricle -> diffusion/transfer to subarachnoid space -> spinal cord/meninges (via foramen of luchka/magendie) -> reabsorption via arachnoid granulations -> drainage into dural venous sinuses
A thunderclap headache prompts emergent evaluation for what severe pathology?
Subarachnoid hemorrhage
ALS patients often develop this condition characterized by inappropriate laughing or crying that is disproportionate to emotion, caused by loss of cortical inhibition, and treated with dextromethorphan-quinidine
pseudobulbar affect
During evaluation for causes of increased intracranial pressure, why must LP be deferred until mass lesions are excluded?
Withdrawal of CSF decreased counter pressure on masses, leading to possible brain herniation due to pressure differences -> brain shift and compression
Which anticonvulsant is a second-line therapy for IIH? How does it work?
Topiramate:
Seizures: Na+ channel inhibition -> inhibits rapidly firing neurons + GABA-A activation & glutamate activity reduction
IIH: weak CA inhibitor -> also has appetite suppression and weight loss effects
What is the Monro-Kellie Principle of intracranial pressure?
the total volume of brain tissue, blood, and CSF within the skull is rigid -> an increase in one requires a decrease in the others to maintain stable ICP. If compensation fails, ICP rises rapidly and can lead to severe brain injury or herniation
Language deficits, spatial neglect, visual field cuts.
Subcortical lesions are pure motor or pure sensory (internal capsule: contralateral hemiplegia; Thalamic stroke: contralateral sensory loss) - no aphasia, neglect, visual field cuts
In ALS, the combination of spastic dysarthria from UMN involvement and tongue fasciculations with atrophy from LMN involvement produces this clinical syndrome affecting speech and swallowing.
Bulbar palsy
What cranial nerve is known as a false localizer, and what pathology must be considered in a "pure" deficit of it
CN 6 - IIH
How does acetazolamides carbonic anhydrase inhibition lead to decreased intracranial pressure?
Decreased H+ and HCO3- availability -> less water and Na+ is drawn into the CSF
A patient presents with a history of 5 attacks of headache lasting 4-72 hours, accompanied by unilateral, pulsating pain. The patient does not report episodes of nausea, vomiting, photophobia, or phonophobia.
Does this fit the ICDH-3 criteria for migraine?
No, patient needs at least one of the following:
1. nausea or vomitting
2. photophobia/phonophobia
Migraine with aura patients are at an increased risk for stroke, what cardiovascular complication associated with migraines with aura further predisposes patients to greater stroke risk
Atrial fibrillation
A 28-year-old woman experiences recurrent episodes where she sees flashing zigzag lines in her right visual field that gradually expand over 15 minutes, followed by a severe left-sided throbbing headache with nausea. The visual symptoms completely resolve before the headache begins. What pathophysiologic mechanism explains her visual aura?
Cortical spreading depression
________, atypical antidepressant that works via norepinephrine and dopamine reuptake inhibition, is commonly used for smoking cessation
Bupropion
A patient presents to the ER with a chief complain of unilateral, pulsating headache with visual "floaties". Following migraine diagnosis, they are started on a class of medication contraindicated for patients with a history of coronary artery disease, what medication was most likely started?
Triptans - due to vasoconstriction function
Nicotine addiction is caused by binding to nicotinic Ach receptors in the brain, causing Na/Ca2+ influx and release of dopamine. What major reward center is associated with dopamine release, causing pleasurable sensations and reinforcement
Nucleus accumbens
Unlike all other migraine subtypes which require at least 5 attacks for diagnosis, this rare variant can be diagnosed after just 2 attacks, and if a first- or second-degree relative also has it, you add the word 'familial' to the name.
Hemiplegic migraine (familial):
A 58-year-old woman with a history of Crohn's disease status post terminal ileum resection 8 years ago presents with 6 months of progressive difficulty walking and numbness in her feet. She describes feeling "like I'm walking on cotton" and has fallen twice recently. She also reports some memory problems and occasional confusion that her family has noticed.
MCV: 112, WBC shows hypersegmented neutrophils
What is the most likely cause of this patients symptoms?
Vitamin B12 deficiency
Triptans should not be combined with this class of medication due to risk of serotonin syndrome
ergotamines