CNS Flashcards
Cause of neural tube defects?
Low folate prior to conception
What is elevated AFP seen in ?
Neural tube defects
What does failure of posterior vertebral arch cause?
Spina bifida
Foramen of monro?
CSF from lateral to third ventricle
Cerebral aqueduct?
Drains 3rd - 4th ventricle
Presentation of aqueduct stenosis?
Enlarging head circumference in infant
Dandy walker?
- Failed cerebellar vermis
- Dilated 4th
- Absent cerebellum
Arnold chiari?
Cerebellar tonsils through foramen magnum
Type 1: asymptomatic
Type 2: obstructed CSF flow
Cause of syringomyelia?
Cystic degeneration of spinal cord from:
- Trauma
- Arnold chiari
Where does syringomyelia usually occur?
C8 - T1
Presentation of syringomyelia?
- Loss of pain and temp
- Intact proprioception
- LMN signs in expands to lower motor horn
- Horner’s if lateral horn knocked out
* **STT knocked out as this crosses in center where syrinx is DCP is preserved as syrinx is not hitting dorsal spinal cord
What occurs is syrinx knocks out lateral horn?
Horner’s
Polio?
Anterior motor horn damage = LMN signs
- Atrophy
- Weakness
- Flaccid paralysis
- Imparied reflexes
What is werdnig hoffman?
“Floppy baby syndrome”
Inherited degeneration of anterior motor horn: presents just like polio buy in baby
What is ALS?
- ## Degenerative UMN and LMN (think ALS is hitting “all the motor horns”)
Destruction of what causes UMN and LMN signs?
LMN: anterior motor horn
UMN: lateral corticospinal tract
What is atrophy / weakness of hands early sign of?
ALS
How to tell ALS form syringomyelia?
In ALS, there is not loss of pain and temperature sensation
Cause of familial ALS?
Zinc-copper superoxide dismutase mutation
What is SOD?
“Superoxide dismutase”
- Converts Oxide to hydrogen peroxide to prevent free radical damage
- Loss of enzyme implicated in familial cases of ALS
What is friedreich ataxia?
- Degeneration of spinal cord and cerebellum:
1. Ataxia: cerebellar
2. Vibratory / proprioceptive loss
3. Lower extremity weakness
4. Absent DTRs
5. HOCM
Cause of freidrichs?
AR: GAA repeat in frataxin gene
- Responsible for iron regulation if out of order leads to ROS via fenton rxn
What are the leptomeninges?
“Light meninges”
- Pia and arachnoid that surround brain - what is inflamed in meningitis
Meningitis in non vaccinated infant?
H flu