Neurology Flashcards
(24 cards)
The bleeding in a subarachnoid hemorrhage occurs between?
the arachnoid and pia mater.
Multiple system atrophy (MSA)
A degenerative neurologic disorder that presents with symptoms of Parkinsonism, unresponsive to levodopa, cerebellar ataxia, orthostatic hypotension, incontinence, impotence, and other autonomic symptoms. Definitive diagnosis may only be made on autopsy evaluation, with CNS tissue showing numerous glial cytoplasmic inclusions.
Neurofibromatosis Type I
Mutation in NF1 tumor
suppressor gene on
chromosome 17.
Café-au-lait spots, Intellectual disability,
Cutaneous neurofibromas, Lisch
nodules (pigmented iris hamartomas),
Optic gliomas, Pheochromocytomas,
Seizures/focal neurologic Signs (often
from meningioma), bone lesions (eg,
sphenoid dysplasia).
Neurofibromatosis Type II
Mutation in NF2
tumor suppressor
gene (merlin) on
chromosome 22.
Bilateral vestibular schwannomas, juvenile
cataracts, meningiomas, ependymomas.
Electrolyte disturbance in subarachnoid hemorrhage
Hyponatremia after SAH (occurring in an estimated 10-40% of cases).
Manifests within 10 days of initial presentation.
The 2 primary/suspected causes of hyponatremia in SAH include syndrome of inappropriate antidiuretic hormone secretion (SIADH) versus cerebral salt wasting.
Epidural vs subdural hematoma
Epidural hematoma:
-High velocity head trauma.
- Patients will have an initial loss of consciousness at the time of injury, followed by a lucid interval lasting minutes to hours, and then rapid deterioration in mental status and loss of consciousness.
- Rupture of the middle meningeal artery which runs along the inside of the skull.
-CT will demonstrate a lens shaped hyperdenisty with or without overlying skull fracture or scalp hematoma.
Subdural hematoma:
- Rupture of cortical veins
- Somnolent and comatose
- Crescent shaped hyperdense collection between the brain and skull.
Lacunar Stroke
Thalamus: unilateral motor weakness and dysarthria.
Other typical lacunar syndromes include sensory stroke if the putamen is involved, ataxic hemiparesis, and dysarthria-clumsy hand syndrome.
The most significant risk factor for lacunar stroke is hypertension
Cauda equina syndrome
affects the spinal nerve rootlets.
Asymmetric motor weakness, saddle anesthesia, hyporeflexia, and late-onset bowel and bladder dysfunction.
Conus medullaris syndrome
Sudden-onset severe back pain with perianal anesthesia, symmetric motor weakness, hyperreflexia, and early onset bowel and bladder dysfunction.
The most appropriate treatment for myasthenia gravis is?
a long-acting acetylcholinesterase inhibitor such as pyridostigmine.
Lhermette sign
electrical pain with neck flexion is seen in multiple sclerosis.
Tourette disorder is often treated with?
A neuroleptic drug such as risperidone.
Neurogenic shock
Organ tissue hypoperfusion resulting from the disruption of normal sympathetic control over vascular tone.
Often arises from spinal cord injuries and frequently occurs in the cervical and upper thoracic spinal cord, especially those above the T6 level.
Leading to hypotension and bradycardia, Hypothermia may occur from reduced peripheral vasoconstriction.
Indications for neuroimaging before lumbar puncture?
Closed fontanelle with signs of elevated intracranial pressure (papilledema, focal neurologic deficits and coma)
Diffuse axonal injury
Impairment greater that imaging findings
MRI: punctate hemorrhages in white matter and blurring of white-gray matter junction.
Postconcussion syndrome
Persistent concussion symptoms for over 4 weeks, such as headaches and sleep disturbances, dizziness, mood changes, and cognitive impairment, without intracranial injury. Management focuses on symptomatic care, with most patients improving within 3 months.
Types of cerebral herniation
Sulfalcine: congulate gyrus is push beneath falx cerebri (contralateral leg weakness)
Tonsillar (fixed, midposition pupils from disrupted innervation)
Uncal (ipsilateral fixed and dilated pupil due to oculomotor nerve compression)
Central cord syndrome
Incomplete spinal cord injury, in older individuals with cervical stenosis following hyperextension neck injuries: anterior compression of the spinal cord, damaging the central grey matter.
Symptoms: primarily affect the upper extremities, including weakness from alpha motor neuron damage, sensory loss from posterior column damage, and reflex loss at the injury site.
The lateral spinal tracts controlling bowel, bladder, and lower limbs are usually unaffected.
Dx: spinal imaging, often revealing cervical spondylosis, cervical myelogram.
Treat: glucocorticoids and surgery.
Tick-borne paralysis
Rapidly progressive ascending paralysis, no fever or sensory issues, and normal CSF. Ticks must feed for 4-7 days and are usually found on patients after careful searching. Tick removal typically leads to spontaneous improvement.
Cervical myelopathy
Occurs due to spinal cord compression in older adults with cervical spondylosis, leading to canal narrowing from osteophytes and ligament ossification.
Neck pain radiating to arms (lower motor neuron signs) and unsteady gait with increased reflexes (upper motor neuron signs). Lhermitte sign (electric shock sensation) may also be present.
MRI is the preferred diagnostic test, and surgical decompression may be needed for severe symptoms.
Internuclear ophthalmoplegia
Is a disorder affecting horizontal gaze due to damage to the medial longitudinal fasciculus (MLF).
The eye on the same side as the lesion cannot adduct, while the opposite eye abducts with nystagmus.
Multiple sclerosis frequently affects the MLF, either unilaterally or bilaterally.
Medications to avoid in myasthenia gravis
Magnesium sulfate
Fluoroquinolones, aminoglycosides
Neuromuscular blockers
CNS depressants
Muscle relaxants
Calcium channel blockers
Beta blockers
Opioids
Statins
The pharmacotherapy of Tourette syndrome
Antidopaminergic drugs, with VMAT2 inhibitors like tetrabenazine preferred over antipsychotics such as risperidone due to lower risks of side effects.
Alpha-2 adrenergic receptor agonists (e.g., guanfacine, clonidine) may be used for patients with comorbid ADHD or behavioral symptoms.
Head CT in cryptococcal meningitis
Noncontrast head CT may appear normal in cryptococcal meningitis but can show leptomeningeal enhancement, micronodules, gelatinous pseudocysts, and ventriculomegaly.
