- Meninges and Ventricular System 15
Hemorrhages & Innervation (Advanced)
■ In epidural hematoma, blood collects between the
periosteal dura and skull.
■ Epidural hematoma assumes a biconvex lens shape.
■ In subdural hematoma, blood collects within the
dural border cell layer, external to the underlying
arachnoid layer.
■ Subdural hematoma assumes a crescent shape.
■ Epidural hematomas are unaff ected by the dural folds
whereas subdural hematomas pool at the site of dural
refl ections.
■ Th e trigeminal nerve innervates the supratentorial
meninges, which includes the meninges of the
anterior and middle cranial fossae.
■ Posterior cranial fossa meningeal innervation is
derived, most notably, from the second and third
cervical spinal nerves and a minor branch of the
v a g u s n e r v e.FornixSeptum
pellucidumFrontal pole
Pituitary glandMidbrain
Pons
Medulla oblongata
Fourth ventricle,
median apertureFourth ventricleCerebellum,
hemisphereCerebellum,
vermisOccipital
poleStraight
sinusCerebral
aqueductThird ventricleInterthalamic adhesionInterventricular foramenSuperior
sagittal sinusArachnoid
granulations181716
1514
13
12 11 10987654319 1 220
Corpus callosumCentral sulcus
Choroid plexus
of lateral ventricle
Lateral sulcus
Lateral
ventricle,
trigone
Lateral
ventricle,
occipital
horn
Lateral
ventricle,
temporal
horn
Fourth
ventricle
Cerebellum,
hemisphere
Choroid plexus of
fourth ventricle
Fourth ventricle,
median apertureMedulla
oblongataFourth ventricle,
lateral aperturePonsCerebral
aqueductChoroid
plexus of
lateral
ventricle,
temporal hornFrontal poleLateral
ventricle,
frontal hornInterventricular
foramenThird ventricleLateral ventricle, body 40 21
39
3837363534
33(^323130)
29
28
27
26
25
24
23
22
A
B
FIGURE 2-1 A. Flow pattern of cerebrospinal fl uid. B. Anatomy of the ventricular system. Used with permission from Woolsey, Th omas A., Joseph
Hanaway, and Mokhtar H. Gado. Th e Brain Atlas: A Visual Guide to the Human Central Nervous System. 3rd ed. Hoboken, NJ: Wiley, 2008.