Neuro Flashcards
Nondominant vs dominant parietal lobe lesions
Most people (90% of righties and 60% of lefties) have Left hemispheric dominance for speech and language.
Construction apraxia is seen with non-dominant (Right usually) parietal lesions. Marked difficulty copying simple line drawings.
Difficulty wearing clothes with struggling as they get into coat or pants is Dressing apraxia and is seen with bilateral or nondominant (right) parietal lesions.
You will also see confusion with nondominant lesions.
Damage to the dominant (usually L) parietal lobe, esp inferiorly leads to Gerstmann Syndrome. Trouble performing arithmetic tasks (acalcula), iniabilty to name individual fingers (finger agnosia), impaired writing (agraphia) and R/L confusion (can’t tell which side is right or left)
Nondominant vs dominant temporal lobe lesions
Nondominant temporal lobe can cause visual disorders (homonymous upper quadrantanopia) and impaired perception of complex sounds (auditory agnosia)
Dominant temporal lobe has homonymous upper quadrantanopia, and almost always involves the language functions leading to aphasia. Wenicke’s aphasia (impairment in comprehension of spoken or written language). Patients have trouble expressing thoughts in a meaninful manner. Apraxia is not seen in temporal lobe lesions
Pseudotumor cerebri
Idiopathic intracranial hypertension
Arises from chonically elevated ICP. Papilledema is evident on exam and may lead to progressie optic atrophy and blindness.
Most common in obese premenopausal women, but may also be associated with endocrine disorders (hypoparathyroidism, hypothyroidism, adrenal insufficiency, Cushing) and the usage of some meds (isotretinon, all trans retinoic acid, minocycline, tetracycline, cimetidine, corticosteroids, danazol, tamoxifen, levothyroxine, lithium, nitrofurantoin)
Reversible causes of falls in the elderly and potential interventions
Vision
- Correction of visual acuity if less than 20/60
- Cataract removal
- ample lighting without glare
Postural BP
- removal of offending meds
- modification of salt and fluid intake
- behavioral strategies (slow change in position)
- compression stockings
Med use
- removal of offending meds (benzos, neuroleptics, sleep meds)
- reduction of polypharmacy
Balance and gait (get up and go test)
- enviornmental modifications
- physical therapy for gait and balance training
- assessment for assistive device
- exercise program
Targeted cardiovascular, msk, and neuro exam
- diagnose and trest underlying cause if identified
home hazard eval
- enviornmental modifications (adjust poor lighting, remove loose rugs, place non-slip bathmats and rails)
get up and go test
Assesses for postural instability in the elderly
Instruct patient to stand up from an armless chair without assistance, walk a short distance, turn around and sit down again. if patient is unsteady, further eval is needed
Wallenberg Syndrome
Lateral medullary infarct (likely from intracranial vertebral artery)
Vestibulocerebellar symptoms
- vertigo, falling to the side of the lesion
- dfficulty sitting upright without support
- diplopia and nystagmus (horizontal and vertical)
- ipsilateral limb ataxia
Sensory
- abnormal facial sensation or pain (early)
- loss of pain and temp in ipsilateral face and contralateral trunk and limbs
Ipsilateral bulbar muscle weakness
- dysphagia and aspiration
- dysarthria, dysphonia, and hoarseness (ipsilateral vocal cord paralysis)
Autonomic dysfunction
- ipsilateral Horner’s (miosis, ptosis, anhidrosis)
- intractable hiccups
- lack of automatic respiration (esp during sleep)
lesions of thalamus or cortex vs brainstem
Sensory loss contralateral face and body. Cortical lesions can also be specific with aphasia, neglect, or agraphesthesia
Brainstem lesions involve cranial nerves and impair sensory perception over ipsilateral face and contralateral body
medulla vs pontine lesion
Pattern of cranial nerve involvement gives it away
Lateral mid-pontine lesions affect ipsilateral trigeminal nerve, causing weakness of muscles of mastication, diminished jaw jerk reflex and impaired tactile and position sensation.
Dysphagia, hoarseness, diminished gag is more likely lateral medullary due to CN IX and X. Motor function is typically spared in lateral medullary infarcts.
Medial medullary: branch occlusion of vertebral or anterior spinal artery. Contralateral paralysis of arm and leg and tongue deviation toward the lesion. Can also see contralateral tactile and position sense loss
Medial pontine: contralateral ataxia and hemiparesis of the face, trunk, and limbs (ataxic hemiparesis).
Traumatic LP
RBC above 6000 without xanthochromia. Can also have WBCs (about 1 per 750-1000 RBCs)
diaphragmatic paralysis
Can lead to orthopnea, which can easily be confused with CHF. Most common causes of b/l diaphragmatic paralysis are neuro diseases like ALS.
Parkinson Disease
Clinical diagnosis. Bradykinesia and tremor or rigidity are essential features. However, these can have diagnostic accuracy of only 26% at initial visit.
Levodopa or dopamine agaonists (pramipexole, bromocriptine) are typically used for initial treatment of PD symptoms. Levodopa is the most effective controlling symptoms but there are concerns about long time use. There may also be limited period of response to levodopa and a higher incidence of levodopa-related dyskinesia in patients with early-onset PD.
Therefore, some people recommend favoring levodopa in patients over 65 who have severe symptoms affecting quality of life. Dopamine agonists like pramipexole can help to save levodopa for a later time when the patient’s symptoms are more severe and it might be preferred as initial treatment in patients less than 65
Entacapone (catechol-O-methyl transferase inhibitor) can extend efficacy of L-dopa
Erythropoiesis in B12 deficiency
Ineffective erythopoiesis is a well known phenomenon in patients with B12 deficiency. Defective DNA synthesis due to megaloblastic transformation of bone marrow and intramedullary hemolysis.
Intense erythroid hyperplasia occurs but erythroid cells are not matured normally and die in the marrow. Markers of hemolytic anemia (LDH, low haptoglobin, indirect hyperbili) may become evident but reticulocyte response is typically absent in these patients.
GBS
GI illness with subsequent development of severe symmetric muscle weakness and absent deep tendon reflexes
GBS usually occurs after GI (campy) or respiratory infection generates cross-reacting antibodies to peripheral nerve components. Resultant immune-mediated polyneuropathy causes:
- symmetric muscle weakness that usually begins in the legs
- paresthesias
- dysautonomia (tachy, urinary retention) that may be life-threatening
- decreased or absent deep tendon reflexes
Patients with GBS are at high risk for deveoloping rapid onset respiratory failure due to respiratory muscle weakness. Frequent measurement of vital capacity is needed. 30% require ventilation
May want EMG and LP, but check vital capacity (tital volume and neg insp force too) first
Disease modifying treatment with plasma exchange or IVIG speeds recovery and reduces need for MV. Patients with GBS received plasma exchange or IVIG if
- nonambulatory
- within 4 weeks of symptom onset
Those who are ambulatory and recovering dont need treatment.
Evolution
- 2 weeks progresssive motor weakness that an lead to paralysis
- 2-4 weeks of plateu’d symptoms
- slow, spontaneous recovery over months
Patients with GBS tend to have impaired neuro recovery if infection was from campy, they had severe motor weakness on admission or required ventilation
IVIG/plasma reduce recovery by 50%
Criteria for thrombolytics in stroke
Inclusion
- Ischemic stroke with measurable deficits
- Symptoms onset less than 3-4.5 hrs before treatment initiation
Strict exclusion
- hemorrhage or multilobar infarct involving over 33% of cerebral hemisphere on CT
- stroke/head trauma in past 3 months
- history of intracranial hemorrhage, neoplasm, or vascular malformation
- recent intracranial/spinal surgery
- active bleeding or arterial puncture in last 7d at noncompressible site
- BP over 185/110
- platelets less than 100 or glucose less than 50
- anticoagulant with INR over 1.7, PT over 15, or increased active PTT
Relative exclusion
- minor or rapidly improving neurodeficits
- major surgery/trauma in last 14d
- MI in last 3 months
- GU or GI bleeding in last 21d
- seizure at stroke onset
- pregnancy
DVT in stroke patients
DVT/PE is a common cause of morbidity/mortality in patients with acute stroke (highest risk at 2-7d, very high in patients with hemiparesis). For hemorrhagic stroke, use compression devices for ppx. All else get subq heparin. Don’t need full anticoagulation (risk of hemorrhagic transformation of infarct)
BP goals in stroke
If you didn’t get tPA it’s 220/120
If you did get tpa it’s 185/105 for at least 24h
DDx of stroke in young adult
Cardiac
- patent foramen ovale
- congenital heart disease
- arrythmia
Heme
- heparn induced thrombocytopenia
- inherited or acquired hypercoaguable state
- sickle cell disease
Infectious
- endocarditis
- varicella zoster virus
- menigovascular syphilis
- bacterial meningitis
- TB meningitis
Other
- Inflammatory arteritis (Takayasu)
- Cocaine, amphetamine use
- cerebral artery dissection
Clinical features of MS
Features suggesting MS
- Onset at age 15-50
- optic neuritis
- Lhermitte’s sign
- Internuclear ophtalmoplegia
- Uhthoff’s phenomenon (heat sensitivity)
- Sensory symptoms (numbness and paresthesia)
- Motor symptoms (paraparesis and spasticity)
- Bowel/bladder dysfunction
Disease pattern
- Relapsing remitting (most common)
- primary progressive
- secondary progressive
- progressive relapsing
Diagnosis
- T2 MRI (preferred modality) lesions disseminated in time and space (periventricular, juxtacortical, infratentorial or spinal cord)
- Oligoclonal IgG bands on CSF
Optic neuritis: monocular visual loss accompnied by eye pain that worsens with eye movement
Transverse myelitis: upper motor neuron signs and sensory loss below the level of spinal involvement
Treatment of MS
Acute MS exacerbation
- oral and IV corticosteroids are equally as effective
- patients with optic neuritis should get IV though (oral has increased risk of recurrent optic neuritis). Oral staper can be considered after IV
- Plasmaphoreis if not responsive to steroids
Chronic maintenance
- disease modifying agents (beta interfon, glatiramer acetate) for relapsing remitting.
Treatment doesn’t really change in pregnancy (unless they’re on teriflunomide or mitoxantrone which are contraindicated in pregnancy)
Symptomatic treatment of common MS findings
Depression - SSRIs, SNRIs
Spasticity
- PT
- Massage
- Baclofen
Fatigue
- sleep hygiene, regular exercise
- amantadine
- stimulants (methylphenidate, modafinil)
Neuropathic pain
- gabapentin or duloxetine
Urge urinary incontinence
- timed voiding
- fluid restriciton less than 2L/d
- antiCh (oxybutynin, tolterodine)
Pediatric traumatic brain injury
High risk features age less than 2
- AMS (fussy)
- LOC
- severe mechanism of injury - fall over 3ft, high impact, MVC
- nonfrontal scalp hematoma (large (over 3cm) parietal and temporal hematomas have highest risk))
- palpable skull fracture
High risk features age 2-18
- AMS (somnolence, agitation)
- LOC
- severe mechanism of injury - fall over 5ft, high impact, MVC
- Vomiting, severe HA
- basilar skull fracture signs (like CSF rhinorrhea)
Mangement of high risk featurs is CT
Manifestations of sarcoid
Pulmonary
- bilateral hilar adenopathy
- interstitial infiltrates
Cutaneous
- papular, nodular or plaquelike lesions
- erythema nodosum
Ophtho
- anterior uveitis (iridocylitis or iritis)
- posterior uveitis
- keratoconjunctivitis sicca
Reticuloendothelial
- peripheral LAD
- Hepatomegaly
- Splenomegaly
MSK
- acute polyarthritis (esp ankles)
- chronic arthritis
CV
- AV block
- Dilated or restrictive cardiomyopathy
CNS/endocrine
- Facial nerve palsy!!!
- Central DI
- HyperCa
Lofgren syndrome
- erythema nodosum
- hilar adenopathy
- migratory polyarthraliga
- fever
Screening of suspected sarcoid begins with CXR!
Biopsy whatever you can easily get to. LAD perferred. Will show noncasseating granulomas.
Danger signs indicating life threatening cause of headache
SNOOP
- Systemic symptoms (fever) or illness (cancer)
- Neuro signs/symptoms
- Onset is new
- Other associated conditions (trauma)
- Previous headaches with change in frequency, severity or presentation
Patients with these findings should get urgent investigation, often with imaging.
Ataxia, weakness, and absent deep tendon reflexes after a camping trip
Tick paralysis
Rare, potentially life threatening disorder n Australia and western US. Neurotoxins from the tick saliva are transmitted to host over 4-7d of tick attachment.
brief prodrome of fatigue and parasthesias. Gait ataxia and ascending paralysis that develop over hours. Absent DTRs.
Next step is meticulous skin exam. Treatment is manual removal of tick. Clinical improvement is within hours. Most will completely recover without further treatment.
Note GBS develops over several days or weeks (not hours) and is often preceded by GI/URI
Benign Essential Tremor
Most common cause of postural tremor. Incidence increases with age. familial cases are auto dominant and present younger
Present in distal upper extremities and becomes much more pronounced with outstretching of arm. Also increases at the end of an activity or movement. All patients typically have no other neuro symptoms.
Presence of family history and a slight head tremor are also seen.
Normal life expectancy. No significant disability. Treatment isnt needed and should be delayed as long as possible due to need for permanent treatment. But if causing distress or interfering with tasks/work, use propranalol (BB)
Absence of a resting tremor (worsens at rest but improves with movement), rigidity, bradykinesia or gait difficulty differentiats from tremors in parkinson.
HA red flags and common diagnoses
Sudden onset, WHOML - SAH
Age 50 and up
- mass
- giant cell arteritis
Increased frequency or severity
- med overuse
- mass
- SDH
worsened by physical activity
- mass
- SAH
FND, papilledema
- mass
- idiopathic intracranial hypertension
- AVM
Personality changes
- CNS infection
- mass
- intracerebral hemorrhage
Systemic symptoms (fever, rash)
- encephalitis
- meningitis
Lateral femoral cutaneous nerve entrapment
Meralgia paresethetica
Small, purely sensory nerve off the lumbar plexus. Area of decreased sensation over the anterolateral thigh without muscle weakness or DTR issues
Reassurance and Advise weight loss and to avoid tight clothes
Local steroid injection and anticonvulsants if persistent after conservative measures
Femoral nerve lesion
Anterior and anteromedial thigh paresthesia with quads muscle weakness and decreased knee jerk
Obturator nerve lesion
Sensory loss over medial thigh and weakness in leg adduction
Diagnostic featurs of Dementia with Lewy Bodies
Central (required) - Progressive cognitive decline, dementia
Core
- Fluctuating cognition!!
- Visual hallucinations (detailed, recurrent)
- Spontaneous parkinsonism features
- REM sleep behavior disorder (dream enactment)
Suggestive
- Severe antipsychotic sensitivity
- SPECT or PET showing low dopamine transporter uptake in basal ganglia
Supportive
- repeated falls
- syncope or near syncope
- severe autonomic dysfunction
- delusions
- depression or anxiety
Conflicting (make DLB less likely)
- Neuroimaging showing cerebrovascular disease
- Parkinsonism appearing FIRST with dementia LATER
Survival time after diagnosis is 8 years. Second most common dementia
Summary: Dementia plus at least 2 of fluctuating cognition, visual hallucination, Parkinsonism, REM sleep disorder