I like to Move it Move It
List all of the innervations and actions for the extraocular muscles
Lateral rectus - abducens nerve; abduction
Superior oblique - trochlear nerve; depression & intorsion
Medial rectus - oculomotor nerve; adduction
Superior rectus - oculomotor nerve; elevation & intorsion
Inferior rectus - oculomotor nerve; depression & extorsion
Inferior oblique - oculomotor nerve; elevation & extorsion
*Honorable mention: levator palpebrae superioris - oculomotor nerve; pulls eyelid superiorly
(1) What are the functions of the direct and indirect pathways? (2) What are the functions of the striatum, pallidum, thalamus, and subthalamic nucleus?
(1) Direct pathway - disinhibits the thalamus; indirect pathway - disinhibits subthalamic nucleus
(2) Striatum - receives input; pallidum - sends output; thalamus - acts as gate to cortex; subthalamic nucleus - modulator of basal ganglia output
(1) What are the 3 A's of consciousness? (2) What are the other important contributors to the consciousness system?
(1) Alertness, attention, awareness
(2) Frontoparietal cortical association areas; arousal circuits in upper brainstem & diencephalon
(1) What arteries supply the thalamus? (2) Which are more common, infarcts or hemorrhages?
(1) Thalamic arteries, originating from the posterior communicating artery supply anterior-lateral thalamus
(2) Infarcts are more common than hemorrhages
Describe the emotional disturbances produced by the following lesions: septal area, right orbitofrontal region, epileptogenic foci in left temporal lobe, right fronto-parieto-occipital & orbitofrontal region
Septal area: irritability
Orbitofrontal region: anxiety, depression, rage
Epileptogenic foci in left temporal lobe: aggression, antisocial & paranoid behavior
Right fronto-parieto-occipital & orbitofrontal region: alexithymia (inability to identify & describe one's own feelings)
Describe right-way eyes and wrong-way eyes
Right-way eyes: eyes look the opposite direction as paralyzed side (left cortical lesion affecting corticospinal pathways & frontal eye fields)
Wrong-way eyes: eyes look towards paralyzed side (left pontine lesion affecting corticospinal pathways and PPRF)
(1) What is the etiology of Parkinson's Disease? (2) What is the histopathology of Parkinson's Disease?
(1) Loss of pigmented dopaminergic neurons in substantia nigra pars compacta
(2) Pallor of substantia nigra, marked depletion of cells & replacement gliosis, Lewy bodies (some remaining cells have inclusions & a faint halo)
(1) What neurotransmitters promote wakefulness? (2) What neurotransmitters promoting sleepiness?
(1) Histamine, Orexin, Acetylcholine, Norepinephrine, Serotonin
(2) GABA, Adenosine
What are the signs/symptoms of ACTH secreting adenomas?
Cushing's syndrome (excess glucocorticoids)
Moon face, buffalo hump, skin striae, acne, hirsutism, easy bruising, diabetes, osteoporosis, amenorrhea, mania or depression
(1) What are alexia and agraphia? (2) What lesions can cause them?
(1) Alexia: impaired reading; agraphia: impaired writing ability
(2) Lesions that cause aphasia (subcortical or cortical lesions in dominant hemisphere)
(1) Axial disequilibrium, staggering gait with little to no limb ataxia, sometime spontaneous nystagmus & rotated head postures
(2) Flocculonodular lobe disease (medulloblastoma in children)
Progressive Supranuclear Palsy; ophthalmoplegia, axial distonia, bradykinesia, shuffling gait, postural instability, procerus sign, NO tremor
What are the similarities and differences between a minimally conscious state and a vegetative state?
Both have severely impaired cortical function with preserved diencephalic-upper brainstem activating functions; a vegetative state is persistent (longer than a month), but the minimally conscious state is variable
What issues are associated with lesions to the paramedian territory (1), anterolateral thalamus (2), lateral & inferolateral thalamus (3)
(1) Problems with alertness, attention, & behavior
(2) Primarily neuropsychological problems
(3) Sensorimotor; contralateral deficit signs
(1) What is Capgras syndrome? (2) What is Fregoli syndrome? (3) What causes these disorders?
(1) Patients insist that their friends/family have all been replaced by identical-looking imposters
(2) Patients believe that different people are actually all the same person in disguise
(3) Right hemisphere lesions
(1) What is pancerebellar syndrome? (2) What can cause pancerebellar syndrome?
(1) Combination of all cerebellar syndromes - involves trunk, limbs, & cranial musculature
(2) Secondary to infection, hypoglycemia, hyperthermia, cerebellar degeneration, cancer, toxic-metabolic disorders, etc.
(1) Define chorea (2) Define athetosis
(1) Chorea: sudden, brief, involuntary, unpredictable jerks affecting the face, trunk, or limbs; "milkmaids grip"
(2) Athetosis: slow, purposeless movements most pronounced in hands & fingers; patient is unable to sustain a position
Describe Locked-In syndrome
Lesion/infarct in ventral pons affecting bilateral corticospinal & corticobulbar tracts; patients are fully aware & able to feel, hear, & understand everything in their environment but is unable to move
Describe Kleine-Levin syndrome
Compulsive eating behavior in adolescent males; hyperphagia, hyperactivity, hypersexuality, exhibitionism; often preceded by some viral illness
Usually resolves by 3rd decade of life with no abnormal endocrinological workup results
Describe Gegenhalten paratonia
Frontal lobe lesions of premotor cortex that cause the patient to tighten muscles when asked to relax so the examiner can move their limbs
*The degree of resistance correlates with the speed of movement*
What are the three rules for cerebellar lesions?
1. Ataxia is ipsilateral to the side of the cerebellar lesion
2. Midline lesions of cerebellar vermis/flocculonodular lobes mainly cause truncal ataxia & eye movement abnormalities
3. Lesions lateral to cerebellar vermis mainly cause appendicular ataxia
(1) What is Wilson's disease? (2) What are the signs/symptoms of Wilson's disease? (3) What are the key lab values in Wilson's disease?
(1) Mutation of ATP7B gene; error in copper metabolism
(2) Degeneration of liver & basal ganglia, Kayser-Fleischer rings, tremors, rigidity, behavioral issues, dystonic movements
(3) Decrease ceruloplasmin; increased serum copper & greatly increased liver copper
What tests can be used to assess for conversion disorders?
Hand-dropping test, saccadic eye movements, variable resistance, Hoover test, unconscious movements, midline change in vibration sense
(1) What are the signs/symptoms of growth hormone secreting adenomas in adults? (2) What are the signs/symptoms of growth hormone secreting adenomas in children (before adolescence)?
(1) Acromegaly; progressive overgrowth of bones & soft tissues, coarsened facial feature, enlarged hands & feet, protuberant jaw
(2) Gigantism; infertility, diabetes, HTN, carpal tunnel syndrome; elevated IGF-1, GH >2 mg/L
(1) What are treatable infectious disorders that can present as dementia? (2) What should be included in your dementia workup?
(1) Cryptococcus, neurosyphilis, Lyme disease
(2) CBC, urinalysis, electrolytes, B12 & folate levels, LFTs, thyroid function tests, drug screen, MRI, EEG, etc.