Pathoma - CNS Review Flashcards
Horner Syndrome
Loss of sympathetic innervation on the affected side of the face secondary to stroke
Due to damage to the lateral horn of the hypothalamospinal tract (above T1)
Presents with ptosis, miosis, and anhydrosis No mydriasis (dilation) response to cocaine drops
Function of cerebrocerebellum (aka neocerebellum)
Found in the lateral cerebellum
Responsible for fine movements of the hands and face
Lesions here would cause dysdiadochokinesis (impairment of rapidly alternating hand movements) and intention tremor
Function of spinocerebellum
Found in the anterior vermis (central) of the cerebellum
Responsible for trunk balance, vocal control, and saccades of the eye
Area most damaged by chronic alcohol use
Function of vestibulocerebellum (aka archicerebellum)
Mostly responsible for eye movements
Damage to this area lead to problems of pursuit an nystagmus (but not saccades)
Fanconi Syndrome
Caused by taking expired Tetracyclines
Type 2 renal tubular acidosis
Histology of Parkinsons
Loss of pigment in substantia nigra
Lewy bodies – round, eosinophilic inclusions composed of alpha-synuclein
Parkinson’s dementia vs. Lewy Body dementia
Both have Parkinsonian features
Parkison’s:
- Dementia occurs LATE in disease
- Affects the substantia nigra
Lewy Body:
- Dementia occurs EARLY in disease
- Lewy bodies found in CORTEX
Dandy-Walker malformation
Congenital failure of the cerebellar vermis to develop
Presents as massive dilation of the 4th ventricle with absent cerebellum
Often accompanied by hydrocephalus
Arnold Chiari malformation
Herniation of cerebellar tonsils through the foramen magnum
Type II – obstruction of the CSF resulting in hydrocephalus
Often associated with meningiomyelocele
Syringomyelia
Cystic degeneration of the spinal cord
Caused by trauma or Arnold Chiari Type I
Occurs at C8-T1 (most inferior nerves of the arms)
Spinal involvement
- Anterior white commissure of the spinothalamic tract (bilat loss of temp and pain in upper extremities with sparing of fine touch and proprioception)
- May extend to anterior horn (LMN signs)
- May disrupt lateral horn or hypothalamospinal tract (Horner syndrome)
Friedrich Ataxia
Degenerative disorder of the cerebellum and spinal cord
Cerebellum - ataxia
Spinal cord - loss of vibrations, proprioception, muscle weakness and loss of DTRs
Due to expansion of trinucleotide repeat (GAA) on the frataxin gene (impairment of mitochondrial function)
Associated with cardiomyopathy
Poliomyelitis
Cause by poliovirus (fecal-oral)
Damage to anterior horn (LMN signs)
Will be asymmetric weakness
Werdnig-Hoffman disease
Same as poliomyelitis (damage to anterior horn - LMN) but due to inherited degeneration of anterior horn
Will be symmetric weakness (vs. Poliomyelitis which will be asymmetric)
ALS (Amyotrophic lateral sclerosis)
Disorder of upper (lateral corticospinal tract) and lower motor neurons (anterior horn damage)
Can differentiate from syringomyelia because there is no loss of pain and temp
Progression of liquefactive necrosis secondary to ischemia in the brain
- Red neurons (eosinophilic cytoplasm, pyknotic nuceli, loss of Nissl substance) appear first (12 hours after infarction)
- Necrosis occurs at 24 hours
- Neutrophils and microglia arrive between 1 day and 1 week
- Healing around 1 week (reactive gliosis and vascular proliferation around the necrotic area)
- Gliotic cyst around 1 month
Charcot Bouchard microaneurysm
Affects small vessels (such as lenticulostriate which provide to the basal ganglia)