Flashcards in Case 1 Deck (24):
What are the three layers of meninges (from outermost inwards)?
Dura, Arachnoid, Pia
What are the four dural partitions?
1. Falx cerebri 2.Tantorium cerebelli 3.Falx cerebelli 4.Diaphragm sellae
What are the attachments of the Flax Cerebri?
A: Crista Galli of ethmoid, frontal crest of frontal bone. P:Tentorium cerebelli. Projects downwards between cerebral hemispheres
What are the attachments of the tantorium cereblli?
P: transverse sinuse grooves of occipital bone A+M are free and form an oval opening called the tentoria notch through which the midbrain passes. Horizontal projection seperating the cerebellum from the cerebral cortex
What are the attachments of the Flax Cerebelli?
P: Internal occipital crest of occipital bone A: Free,
Outline the Arachnoid mater
Thin avascular membrane, against but not adherent to dura mater, trabeculae extend through subarachnoid space and become continuous with pia mater, does not enter grooves of brain
Outline Pia Mater
Thin delicate membrane, that adheres to the brains contours.
What is the ventricular system in the brain?
4 - 2 lateral, a 3rd and 4th, interconnected by chennels and continuous with central canal.
What is the shape and location of the lateral ventricles?
Located in cerebrum, C-shaped, large, roughly wrap around dorsal aspect of basal ganglia. 3 horns extend into different lobes, anteriorly into frontal, inferiorly into temporal, and posteriorly into occipital.
Where is the third ventricle located and how does it communicate with the lateral ventricles?
Midline, below two lateral, appears as a thin slit on coronal sections. Communicates through interventricular foramen in diencephalon
Where is the fourth ventricle located and how does it communicate with the third?
Hindbrain, communicates through cerebral aqueduct.
What cells migrate to the head of the embryo to form the notochoral process and where to they come from?
Mesodermal cells from the primitve node
What does the notochord stimulate?
Ectordermal cells to form the neural plate.
What is the small intermediate horn?
accumulation of neurones between the two areas, contains sympathetic portion of autonomic nervous system and is only present at thoracic and upper lumbar levels
What secretes sonic hedgehog (Shh), where does it travle to and what is its effect?
Secreted by the notochord, travles extracellularly to the ventral region of the neural tube and insturcts the cells to form the floor plate and diverse ventral cell types.
What is the receptor for Shh
What bone morphogenic proteins (BMP) are relevent in spinal cord formation and where are the secreted from?
4 + 7, from the overlying ectoderm
What test of maternal blood can show a neural tube defect?
alpha-fetoprotein levels, main source of whic is the foetal liver, an open NTD can allow extra leakage into the mothers blood. An increase is best detected at 16-18 weeks of pregnancy. Can not be used to detect closed NTD and is less sensitive for women taking sodium valporate.
Other than blood, how else can alpha-fetoprotein levels be measured?
What percentage of children suffering spina bifida have mylomeningocele?
What are some common symptoms of spina bifida?
Varying degrees of paralysis, loss of bowel and urinary control, loss of skin sensation, hydroencephalus, tethered spinal cord (from scar tissue of initial surgery) can lead to lower body pain, leg weakness, incontinence and scoliosos.
What are the risk factors leading to spina bifida?
Obestiy, folic acid deficiency, anticonvulsant medicine, possibly genetic basis (first child suffers spina bifida, 4-5% chance subsequent children will too) insulin dependent diabetes, female babies.
Lifetime risk and onset of bipolar disorder?
1% life time risk, with onset usually during teeanage years.