Anatomy Flashcards
How many layers compose the cranial dura? What are there names?
External Periosteal Layer and Inner Meningeal layer
How many layers compose the spinal dura? What composes the spinal dura? Where does the spinal dura end?
One layer
The inner meningeal layer of the cranial dura
Ends at S2
What two layers compose the leptomeninges? Which one is characterized by the presence of tight junctions?
Arachnoid (tight junctions) and Pia
What are the two layers of the pia?
Initmal and Epipial Layers
The outer layer of the pia is covered by _____
simple squamous epithelium
What is the dentate ligament?
thickening of the pia that stretches from the midpoint between the dorsal and ventral roots on the lateral spinal cord to attach to the surface of the arachnoid and dura
What is the filum terminale? Where is it and what derives from it?
extension of epipia which condenses and continues from S2 down; ends as the coccygeal ligament
What are Virchow Robin Spaces?
a perivascular potential space existing between the blood vessels and the leptominges as the vessels enter the CNS tissue
Name the midbrain cisterns.
Interpeduncular
Crural
Ambient
Quadrigeminal
What vessels are contained within the ambient cistern?
vein of Galen
Posterior Cerebreal Artery (PCAs)
Superior Cerebellar Arteries (SCAs)
What are the three meningeal arteries and what vessels are they branches of?
Anterior Meningeal Artery branch of the Ophthalmic Artery
Mindle Meningeal Artery branch of the Maxillary Artery
Posterior Meningeal Artery branch fo the Occipital and Vertebral Arteries
Which nerves innervate the supratentorial dura?
V1 - Anterior Fossa
V2 - Middle Fossa
V3 - Posterior Fossa and mastoid air cells
What is the embryologic origin of the dura, subarachnoid, and pia?
Dura - Mesoderm
Leptomeninges - Neuroectoderm
What innervates the infratentorial dura?
CN X, C2-C3
What is Froin’s Syndrome? What triad characterizes is?
Characterized by the triad of: 1. Xanthrochromia 2. CSF coagulation 3. CSF protein increased (up to 1000)
Generally occurs whenever there is obstruction to flow causing stasis or if the CSF becomes loculated
What RBC to WBC ratio defines a traumatic tap?
at least 700 RBCs per 1 WBC
What cellular mechanism is fundamental to CSF production?
Na/K ATP pump
What nucleus and molecule control CSF production?
Raphe Nucleus sends serotonin to periependymal vessels
What two factors can increase production of CSF?
Volatile Anesthetics and CO2
What two factors decrease production of CSF?
Carbonic anhydrase inhibitors (acetazolamide) and Norepinephrine
How much CSF is produced per hour? Per day? What is the total volume of CSF?
20 mL/h
450 mL/day
150 mL total
What comprises the choroid plexus?
single layer of cuboidal epithelial cells surrounding blood vessels
Where are the primary locations of choroid plexus?
- Roof of the 4th ventricle
- Inferior Medullary Vellum
- Lateral Recess to the foramen of Luschka
- Posterior roof of the 3rd Ventricle
- Floor of the body of the Lateral Ventricle
- Roof of the temporal horn of the lateral ventricle
What three components make up the Blood Brain Barrier?
- Capillary endothelial tight junctions (primary)2. Pinocytic Activity in endothelial cells3. Astrocytic foot processes