1.4.3 Skull, Cranial Cavity, and Suboccipital Region Flashcards
ID these dural sinuses
ID this bone and its key features
ID this area and what sits in it
Sella Turcica; Pituitary gland
Under pathological conditions an increase intracranial pressure above (or decreased pressure below) which structure can lead to herniation of the brain?
Tentorium cerebelli
Results from a tear in an artery located within the periosteal layer of the dura mater that supplies the bone (ex. middle meningeal artery). Blood accumulates in the epidural space b/t dura and bone`
Epidural hemorrhage
If a fracture occurs along these red lines, what are their classifications?
What type of hemorrhage is often produced by HTN and results in paralytic strokes?
Intracerebral hemorrhage
Which joint is responsible for the “yes” head movement? Which joint for the “no” head movement?
Yes: Atlanto-occipital joint
No: Atlantoaxial joint
What is the term for the breakage of the posterior arch of the axis?
“Hangman’s’ Fracture
What are the 3 layers of the cranial meninges and their characteristics?
Dura mater- tough connective tissue
Arachnoid mater - cobweb-like connective tissue
Pia mater - covers the brain surface: according to the “gross anatomy” definition it is the “vascular layer” that covers the external brain surface
What passes through the foramen magnum of the occipital bone?
Medulla oblongata, spinal roots of CN XI, two vertebral arteries, one anterior and two posterior spinal ateries, plus meninges
Hypertrophy of the arachnoid villi resulting in ___ which may form pits on the inner table of the cranial bones along the superior sagittal sinus
Arachnoid granulations
ID
What produces 60% of the CSF?
Choroid plexus within the lateral ventricles
ID meningeal arteries
Bottom: Middle meningeal artery
Top: anterior branch
What can be torn due to hyperextension of the neck, often caused by sudden forward acceleration of the body (i.e. getting rear ended)?
Anterior longitudinal ligament; anterior neck muscles are stretched +/or torn
Which part of the temporal bone?
Petrous
What is the term for sites of fibrous sutures where several bones meet?
Fontanelles
ID this cranial bone and some of its key landmarks
Results from a tear in a vessel located “deep to” the dura yet outside the arachnoid layer. Blood accumulates b/t the dura and arachnoid layer
Subdural hemorrhage
Term: combination of the pia and arachnoid meninges. When a brain is removed from the skull the ____ with some cerebral blood vessels cover the brain.
Leptomeninges
What type of craniosynostosis results from early closure of the sagittal suture? early closure of the coronal suture?
Sagittal: Scaphocephaly
Coronal: Oxycephaly or Turricephaly
ID these features of the sphenoid
What types of ossification contribute to skull development?
Both intramembranous and endochondral
Typically due to rupture of an aneurysm as arteries pass within the subarachnoid space. This produces blood within the CSF and causes severe headache, stiff neck, and often LOC.
Subarachnoid hemorrhage
Identify 25, 6, 24, 20, 2, and 4
25: super ciliary arch
6: gabella - smooth area b/t super ciliary arches
24: Supraorbital notch (passage of supraorbital nerve and artery)
20: nasion - medial junction of frontal and nasal bones
2: Coronal suture - b/t frontal and parietal bones (not from this picture)
4: supratrochlear notch
When does the anterior fontanelle close? Posterior fontanelle?
Anterior: 18-24 months; becomes the bregma
Posterior: 9 months; becomes lambda
Time of closure determines head shape
Which layers of the meninges participate in this fold? What is the name of the fold?
all 3 layers of the meninges, falx cerebri
What muscle flexes the atlanto-occipital joint?
Rectus capitis anterior
What part of the occipital bone articulates with the atlas?
Occipital condyles
What is the term for premature closure of the sagittal, lambdoind, and coronal sutures leading to deformities of the head which inhibit proper brain development?
Craniosynostosis
ID this bone and its features
