Download Neurosonography Part ONE

Neurosonography Part ONE
Harry H. Holdorf PhD, MPA, RDMS (Ab, OB/Gyn, BR), RVT, LRT
Introduction
7-10 MHz transducer
 Scans are performed through
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The anterior fontanelle;
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The coronal suture or the squamous portion of
the temporal bone;
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Coronal planes
sagital planes
Axial plane , to identify extracerebral fluid
Doppler studies of the “Circle of Willis”
Posterior fontanelle;
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Evaluation of the posterior fossa
Embriology, Color page 169

Centeral nervous system develop from
ectoderm; it folds back and forms the “neural
tube” which makes the CNS:
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
Surrounding mesoderm forms:
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
brain and spinal cord
Cranium, vertebral column, muscles
After 3 weeks development- three regions:
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Fore brain (prosencephalon)
Midbrain (Mesencephalon)
Hindbrain (Rhombencephalon)
Embriology images
Embriology
Embriology images
Embriology
Forebrain( Prosencephalon)

Forms:

Telencephalon- forms
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Cerebrum
Surrounds the Lateral ventricles
Diencephalon
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Thalamus
Hypothalamus
Epithalamus
Surrounds the 3rd ventricle
Midbrain

Forms Mesencephalon which develops
into:
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Cerebral peduncles
Colliculi
The Aqueduct of Sylvius is located at this
level.
Hindbrain (Rhombencephalon)

Forms:
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Metencephalon (Upper)
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Pons
Cerebellum
The Upper part of the 4thventricle is located at
this level.
Myelencephalon (Lower)

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Spinal cord
Medulla Oblongata
The Lower part of the 4th ventricle is located at
this level.
Bones of cranium
Color pages 24-25
One frontal bone- Form forehead
 Two parietal bones- Form top
 Two Temporal bones- Form sides
 One Ethmoid bone - between eyes
 One Sphenoid bone
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Anterior to temporal bone
Wing-like shaped “sella tursica” holds pituitary
gland-located: @ center of Sphenoid bone
One occipital bone; large hole(Foramen
Magnum) for passage of the spinal cord
Bones of cranium lateral view
Bones of cranium top view
Cranium bones interior view
Sutures, Page 24 of coloing book

Bones are connected by sutures, which
are fibrous movable joints.

Allow for molding of the skull during birth.
Sutures cont.

Sagital suture
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Coronal suture
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Between frontal and parietal bones
Perpendicular to sagital suture
Lambdoidal suture
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Between parietal bones- Form ant. And pos. fontanels
Closes from posterior to anterior
Fuses when frontal fontanels closes
Between parietal and occipital bones
Courses from mastoid portion of temporal bone to
posterior portion of sagital suture
Squamosal suture

Between temporal and parietal bones
Skull of new born
Skull sutures and fontanels in neonates
Skull sutures top view
Skull sutures lateral view
Skull sutures lateral view
Skull sutures posterior view
Fontanels:

Anterior Fontanel
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Posterior Fontanel
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Junction of sagital and coronal sutures called
Bregma
Closes between 5-18 months
Junction of sagital and lambdoidal sutures
called Lambda
Closes between 2-6 months
Lateral Fontanels

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Sphenoidal/squamosal fontanels- Ant., closes
@ 2-3 months.
Mastoid fontanels-post., closes @ 12 months
Fontanels
Fontanels
Cranial Meninges: Page 81

There are three layers of meninges:
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Dura Mater- Outer layer
Arachnoid- Middle layer
Pia Mater- Innermost layer, highly vascular
The cerebral meninges are continious with
the spinal meninges
 The main function of meninges and CSF
(cerebrospinal fluid) is to protect the brain
and cord

Cranial Meninges:
Dura Mater

Folds inward and divide the cranial cavity.
These folds include:
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Falx cerebri- Between the cerebral
hemispheres
Falx cerebelli- Between the cerebellar
hemispheres
Tentorium cerebelli- Between cerebrum and
cerebellum
Diaphragma sellae- Forms a bridge over the
Sella Turcica
Cranial Meninges cont.
Dura Mater is separated from Arachnoid
by the subdural space.
 Arachnoid is separated from Pia Mater
by the subarachnoid space.
 Note- Subarachnoid space is where fluid
is sampled for a spinal tap in the lumbar
region.

Cranial Meninges cont.
The convolutions of the surface of the
brain are called Sulci and Gyri.
 The hills are gyri while the furrows are
sulci.
 The pia mater and arachnoidnare in close
contact with gyri. Pia mater follows the dip
of sulci while arachnoid bridges over the
top of gyri and make subarachnoid
spaces.

Grey and White matter organization
of the brain and cord:
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White matter:
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Found on The inner portion of the crebrum
Found on The outer portion of the spinal cord
Mostly axons
Grey matter:
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Grey matter of cerebrum divides into:
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Grey matter of the cerebral cortex
Grey matter of the basal ganglia
Grey matter of the cerebellar cortex
Grey matter of the inner portion of the spinal
cord
Mostly cell bodies
Regions of the brain (CNS)
Cerebrum
 Diencephalon
 Cerebellum
 Brain stem

CNS
Cerebrum
Largest portion of the CNS
 Has two hemispheres.
 There is a deep cleft between the cerebral
hemispheres called Longitudinal Fissure
or Interhemispheric Fissure.
