General anatomy Flashcards
What are the functional divisions of the cerebellum?
Vestibulocerebellum
Spinocerebellum
Pontocerebellum
What does the vetibulocerebellum do?
Balance, spatial orientation and muscular tone
What does the Spinocerebellum do?
Sensing proprioceptive input
Adapting the body to changing circumstances
What does the Pontocerebellum do?
Regulate small limb movements, inhibits involuntary movements
What is dura matter?
Stong, thick dense membrane
supports and surrounds dura sinuses
What is arachnoid matter?
Middle layer
Surrounds spinal cord and brain
What is pia matter?
Innermost layer
Thin fibrous tissue, covering outside by flat cells
What is extradural space?
Potential space inside the cranial vault
Only noticable if underlying pathology
What is subdural space?
Space that can opened by separation of arachnoid mater from dura matter
Result from trauma
Pathologic absence of CSF
Sulcus
Grooves in cortex
TWO S’s
Fissure
Large furrow that divides the brain lobes
Gyrus
Ridge of cerebral cortex
Insula
Small region of cerebral cortex located deep within lateral sulcus
Longitudinal fissure
Deep groove that separates the left and right hemisphere
Lateral fissure
Divide both the frontal and parietal lobe from temporal lobe
Corpus collosum
Nerve fibre bundle between left and right hemispheres- beneath cerebral cortex
Folia of cerebellum
Little folds or gyri- sectioned either parallel to their long axis or transverse
Vermis of cerebellum
Located medial, corticonucelar zone
Lobes of the cerebellum
Anterior- Closer to the cerebrum, smaller lobe
Posterior- More posterior
Flocculomondular- comes off posterior towards the brainstem
Production and reabsorption of CSF
Produced in choroid plexus, located in lining of ventricles
Capillaries and connective tissue surround
Plasma filtered out by blood by epithelial cells to produce CSF
Functions of the CSF
- protection- act as cushion
- Buyoncy- immersed in CSF the net weight of brain is reduced approx 25 grams
- Chemical stability- CSF creates an environment to allow it
What are the 3 different ventricles
lateral ventricle
Third ventricle
Fourth ventricle
Drainage of CSF
Subarachnoid cisteras
What are the 2 protrusions of the 3rd ventricle
Supra-optic recess- optic chiasm
Infundibular recess- optic stalk
How does 4th ventricle receive CSF?
Cerebral aquaduct
4th ventricle drains to:
- cerebral spinal cord
2. subarachnoid cisteras
2 classifications of hydrocephalus
- Communicating (non abstructive)- functional impairment of arachnoid granulations- following haemorrhage
- Non-communicating (obstructive)- Flow obstructed within the ventricle
Blockage in the cerebral aquaduct
Bones of neurocranium
- Occipital
- temporal
- frontal
- parietal
- sphenoid
- ethmoid
*8 all together- temporal and parietal each have 2
Bones of viscercranium
- mandibular
- zygotmatic
- maxilla
- nasal
- lacriminal
- palatine
- inferior nasal concha
- vomer
Main sutures
Coronal- fuses frontal bone with 2 parietal bones
Sagittal- fuses parietal bones with each other
Lambdoid- fuses the occipital bone with 2 parietal bones
2 main fontanelles
Frontal= between coronal and sagittal occipital= between sagittal and lambdoid
Laterality
Ipsilateral- same side
Contralateral- Opposite side
Male and female skull comparison
Male
- Cranial mass more bulky
- Zygomatic bone more prominent
- mandible more squared
- deeper cranial mass
- Supercillary arch is males is large and pronounced
- External occipital protuberance larger
Female
- Suproorbital margin is sharper
- More pointed chin
What are the 4 pairs of parasinal air sinuses
- maxillary- cheeks
- ethmoid- nose
- sphenoid- by ears
- frontal- forehead
What is the most delicate part of the skull?
Pterion- where frontal bone , sphenoid greater wing, temporal and perietal articulate
