-
Hirschsprung's disease
- NCC: missing rectal ganglia
- myentreric plexus dysfunction
-
Horner's
- (all ipsilateral)
- Ptosis
- Anhydrosis
- Miosis
- Peripheral: T1, stellate, carotid endorectomy
- cervical rib, apical lung tumor, pancoast
-
Descending hypothalamic axons or hypothalamospinal
- drive all preganglionic sympathetic neurons
- CENTRAL HORNER'S SYNDROME
-
central vs. peripheral
peripheral: face only decreased sweating vs. whole body
-
Pancoast tumor
- pulmonary sulcus tumor or superior sulcus tumor
- tumor of the pulmonary apex
- Most Pancoast tumors are non-small cell cancers.
- Can compress of a brachiocephalic vein, subclavian artery, phrenic nerve, recurrent laryngeal nerve, vagus nerve, or, characteristically, compression of a sympathetic ganglion resulting in a range of symptoms known as Horner's syndrome.
-
Nissle bodies
- rough ER: synthesis neurotransmitter
- NOT in axon->
-
subcellular neuron transport
- anterograde (400mm/day): microtubules, kinesin move proteins to axon terminal
- retrograde (200mm/day): microtubules, dynein transport lysosomes and recycled membrane
- retrograde: neurotrophic viruses, zoster, herpes, polio, rabies, tetanus(toxin)
- mainly via motor
-
What kind of nerves can regenerate?
- PNS & myelinated by schwann cells
- endoneurium
- rate of 1-3mm per day about the rate of diffusion
-
Which cranial nerve cannot regenerate if severed?
CN II: extension of brain-> oligodendrocytes and meninges
-
What are the most common brain neoplasms?
- Glioblastoma: supratentorial, compress portion of cerebral hemisphere
- Meningioma:
- Schwannoma: MC (VIII) can compress facial CN V
-
craniopharyngioma
- Rathke's pouch
- histology: adamantioma
- optic chiasm compression
- calcified
-
choroid plexus
in all 4 ventricles
-
3 openings in 4th ventricle
- 2 foramena of luschka (lateral aperture)
- 1 foramen of Magendie (median aperture)
-
cerebral aqueduct features
- midbrain
- connect 3rd & 4th ventricles
-
CSF production
400-500cc with space 90-150cc
-
What feature of Normal pressure hydrocephalus is common with Parkinsons?
- apraxic (magnetic) gait
- NPH: wacky, wobbly, wet -> dementia, apraxic gait, (infantile) incontinence
-
Bladder control
- 1. sacral spinal cord (autonomic)
- 2. brainstem: inhibit emptying reflex allow filling
- 3. cortex: voluntary
-
Defects in neural crest cells can cause which of the following
- A. Cyanotic cardiac malformation
- B. Carniopharyngioma
- C. Septum secundum atrial defect
- D. Mutliple Sclerosis
- E. Tracheoesophageal fistula
-
-
- A.
- A. Cyanotic cardiac malformation
- B. Carniopharyngioma: oral ectoderm of Rathke's pouch
- C. Septum secundum atrial defect: septum primum not secundum
- D. Mutliple Sclerosis: NCC form schwann cells not oligodendrocytes
- E. Tracheoesophageal fistula: mesoderm
-
What is Clarke's nucleus?
- relays proprioception to cerebellum
- dorsal spinocerebellar tract
- lower limb
- Friedreich's ataxia: ataxia, dysarthria, muscle weakness or paralysis and skeletal defects
-
Renshaw cells
- tetanus toxin target
- inhibitory interneurons
- gray matter of the spinal cord
- associated w/ alpha motor neuron.
- receive an excitatory collateral from the alpha neuron's axon as they emerge from the motor root, and are thus "kept informed" of how vigorously that neuron is firing.
- They send an inhibitory axon to synapse with the cell body of the initial alpha neuron and/or an alpha motor neuron of the same motor pool.
- negative feedback mechanism.
- may be supplied by more than one alpha motor neuron collateral and it may synapse on multiple motor neurons.
-
corticospinal tract (pyramidal)
- UMN axons down spinal cord
- contains mostly axons originated from the motor cortex
- made up of: the lateral corticospinal tract and the anterior corticospinal tract
- contains the Betz Cell (the largest pyramidal cells)
- discrete voluntary skilled movements, such as precise movement of the fingers and toes
- decuss in the medulla oblongata (medulla-spinal cord junction)
-
What is the UMN effect on muscle stretch reflexes?
- net inhibitory (on future or excessive contractions)
- therefore lesion will lead to clonus, spasticity of reflexes
- net inhibitory on golgi tendon organs too (hypersensitive)
- clasp knife
-
When a neuron undergoes wallerian degeneration how does it present clinically?
- fasiculations: random twitches of denervated.
- then atrophy
-
Pt falls and after cannot spread fingers, what bone is fractured or dislocated?
hamate->ulnar nerve
-
Important wrist bones
- hamate->ulnar nerve, spread fingers
- lunate->carpal tunnel syndrome
- scaphoid->most freq fractured carpal bone, avascular necrosis
-
Tabes dorsalis
- syphilitic myelopathy
- slow degeneration (specifically, demyelination) of the sensory neurons that carry afferent information
- in the dorsal columns (posterior columns) of the spinal cord
- (proprioception), vibration, and discriminative touch.
- parasthesia
- pain
- polyuria
- "sensory ataxia"
- positive Romberg's test (close eyes->sway)
- impaired response to light (Argyll Robertson pupil)
-
Romberg's test
person requires at least two of the three following senses to maintain balance while standing: proprioception (the ability to know one's body in space); vestibular function (the ability to know one's head position in space); and vision (which can be used to monitor [and adjust for] changes in body position).
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