Nervous System - Specific Findings Flashcards
Markus-Gunn Pupil
Noted on swinging flashlight test, due to optic nerve defect - the affected eye does not sense incoming light via CNII and so fails to constrict appropriately; the unaffected eye constricts appropriately and so the affected eye seems to relatively dilate
Multiple Sclerosis - Findings
Increased protein and oligoclonal bands in CSF
MRI shows periventricular plaques (areas of oligodendrocyte loss and reactive gliosis)
Multiple white matter tract lesions in spinal cord separated in space and time
Associated with HLA-DR2
Neuroleptic Malignant Syndrome
Adverse reaction to typical psychotics
Characterized by hyperpyrexia, encephalopathy, autonomic instability (hypotension), muscular rigidity, myoglobinuria
Treated with D2 agonists (bromocriptine), dantrolene
Senile Plaques
Extracellular B-amyloid plaque deposition seen in Alzheimer Disease
Neurofibrillary Tangles
Intracellular deposition of insoluble tau protein
Seen in Alzheimer Disease
Pick Bodies
Spherical tau protein aggregates
Seen in Pick Disease (frontotemporal dementia)
Lewy Bodies
a-synuclein inclusions
Seen in Lewy Body Dementia and Parkinsonism
In Parkinson Disease, eosinophilic cytoplasmic inclusions of alpha-synuclein are seen in the pigmented dopaminergic neurons of the substantia nigra
Hydrocephalus Ex Vacuo
Appearance of excess CSF within the ventricles due to cortical atrophy; intracranial pressure is actually normal
Seen in Alzheimer Disease, advanced HIV, Pick Disease
Romberg Sign
Patient is asked to close their eyes and maintain a standing posture; loss of balance is considered a positive Romberg test
Evaluates the proprioceptive functioning of the spinal dorsal columns; positive test indicates sensory ataxia, i.e. as seen in Tabes Dorsalis
Argyll-Robertson Pupil
Bilateral, small pupils that constrict with convergence (i.e. they accommodate), but do not constrict to light (either direct or consensual)
Highly specific sign of neurosyphilis
Charcot Joint
i.e. Neuropathic Arthropathy
Progressive degeneration of a weight-bearing joint associated with decreased peripheral sensation/proprioception; results in bony destruction/resorption, deformity, and ulceration
Common causes include diabetic neuropathy, Tabes Dorsalis (syphilis)
Tabes Dorsalis
Bilateral demyelination of the spinal dorsal columns seen in tertiary syphilis; causes impaired sensation/proprioception with progressive loss of coordination (sensory ataxia)
Findings: Decreased/absent DTRs, Positive Romberg Test
Negri Bodies
Cytoplasmic inclusions seen inside cells infected with Rabies virus; often seen in Purkinje cells of cerebellum and hippocampal neurons
CSF Findings - Bacterial meningitis
Elevated WBC count (predominantly neutrophils)
Elevated opening pressure
Elevated protein
Low glucose
Most common causes of bacterial meningitis - neonates (3)
Group B Strep (Strep agalactiae)
E. coli
Listeria
Most common causes of bacterial meningitis - kids (3)
Strep pneumo
H. influenzae
N. meningiditis
Most common causes of bacterial meningitis - teens/adults (2)
Strep pneumo
N. meningiditis (#1 in teens)
Most common causes of bacterial meningitis - elderly (3)
S. pneumoniae
Gram negative rods
Listeria
Epidural hemorrhage
“Lens-shaped” hyperdensity on CT
Does not cross suture lines; can cross falx and tentorium, causing transtentorial herniation w/ CNIII palsy
Subdural hemorrhage
“Crescent-shaped” hyperdensity on CT
Crosses suture lines but does not cross falx / tentorium; causes sub-falcine herniation with mid-line shift
Subarachnoid hemorrhage
Hyperdense accumulation of blood within the sulci or ventricles on CT
+ blood in CSF on spinal tap
Intraparenchymal hemorrhage
Hyperdense accumulation of blood most frequently within the basal ganglia and internal capsule
Which HLA type is associated with MS?
HLA-DR2
Winged Scapula
Caused by damage to the long thoracic nerve; vulnerable to damage during breast surgery, injury to the axilla or lateral wall of the thorax
Claw hand
Caused by damage to the ulnar nerve; vulnerable to damage with fracture of the medial epicondyle of the humerus (“funny bone”)
Presents with hyper-extension of the MCP and flexion of the DIP and PIP joints of the 4th and 5th digits
Large, well-circumscribed, supra-sellar mass +/- calcifications in a child - most likely Dx?
Craniopharyngioma
Cushing’s Triad
Irregular respiration (due to compromised function of respiratory center in the brainstem)
Bradycardia
Hypertension
Trendelenburg Gait
Caused by damage to the superior gluteal nerve which innervates the gluteus medius and minimus, responsible for pelvic stabilization during walking
The pelvis sinks to the opposite side with the patient standing still; on walking, the trunk lurches to the side with the lesion
Often seen as a result of polio
