Anatomy Workbooks Flashcards
Briefly describe the process of neurulation and division of the neural tube
- Neural plate formation
- Neural folds form
- Neural folds fuse forming the neural tube
Neural tube closure proceeds in cranial and caudal directions
Be able to name structures of a fully formed brain derived from each of the vesicles and neural tube cavity (ventricles)
3 primary vesicles: forebrain, midbrain, hindbrain
What brain structures are derived from the forebrain?
Telencephalon, Diencephalon:
- Cerebrum
- Thalamus
- Hypothalamus
What brain structures are derived from the midbrain?
Mesencephalon:
- Midbrain
What brain structures are derived from the hindbrain?
Metencephalon, Myelencephalon:
- Pons
- Cerebellum
- Medulla oblongata
What ventricles are associated with the forebrain?
Lateral ventricle
Third ventricle
What ventricles are associated with the midbrain?
Mesencephalic aqueduct
What ventricles are associated with the hindbrain?
Fourth ventricle
Define the terms rostral, caudal, anterior/ventral, posterior/ dorsal in relation to the brain and spinal cord.
Rostral- towards the nose
Caudal- towards back of brain/bottom of spinal cord
Ventral- front
Dorsal- back
Define the term peduncle
Band of neurons connecting parts of the brain.
Cerebral peduncle- connect cerebrum and mid brain
Cerebellar peduncles- connect cerebellum and brain stem (superior, middle, inferior)
Define the term commissural fibres
Run horizontal
Create corpus callosum
Connect corresponding gray areas of right and left hemispheres
Define the term association fibres
Connect different parts of the same hemisphere
Define the term projection fibres
Run vertically ascending and descending to form the spinal cord
Connect at the decussation of pyramids
Define the terms decussation and chiasm
Decussation- crossing of two tracts that form the letter X
Name the arteries entering the cranial cavity to supply the brain and describe their course and branches.
Vertebral arteries
Internal carotid arteries
Arise in the neck and ascend to the cranium
Describe the formation of the circle of Willis and its clinical importance
Joining area of the internal carotid arteries and vertebral arteries
Maintains adequate cerebral perfusion
List the blood vessels supplying the different parts of the brain
Anterior cerebral
Middle cerebral
Posterior cerebral
Describe the arterial supply to the spinal cord
Anterior spinal arteries
Posterior spinal arteries
Describe the venous drainage of the brain
Venous sinuses
Great cerebral vein of Galen
Name and locate the dural venous sinuses
Superior sagittal
Inferior sagittal
Straight
Occipital
Transverse
Sigmoid
Cavernous
Intercavernous
Superior and inferior petrosal
Describe the location and anatomy of the cavernous sinus
Located in middle cranial fossa either side of the body of the sphenoid bone
Identify the three meninges and state what is found between the layers of meninge
Dura
Arachnoid
Pia
CSF is in subarachnoid space
Describe the arterial supply of the dura mater and the origin and course of this artery.
Middle meningeal artery
Branch of Maxillary artery, one of the 2 terminal branches of the ECA
Name the folds of dura mater
Falx cerebri
Tentorium cerebelli
Falx cerebelli
Diaphragm sellae
Identify the dural venous sinuses within the folds of dura
Falx cerebri: superior sagittal, Inferior sagittal, straight sinus
Tentorium cerebelli: transverse sinus, superior petrosal sinus, straight sinus
Falx cerebelli: occipital sinus
Define the term haematoma and distinguish between extradural and subdural haematoma in terms of their anatomical basis.
Collection of blood outside the blood vessels
Extradural- between dural mater an dinner surface of the skull
Subdural- blood collects under the dura mater
State the location of the cerebrospinal fluid in the central nervous system
Subarachnoid space
Describe how and where the cerebrospinal fluid is formed
Formed in the choroid plexus of lateral ventricles
Describe the circulation and reabsorption of the CSF.
Produced in lateral ventricles
Circulates through interventricular foramens into the 3rd ventricle
Passes via cerebral aqueduct to 4th ventricle
Passes from 4th ventricle into subarachnoid space by a sign median aperture (of Magendie) and paired lateral apertures (pf Lushka)
Reabsorbed by arachnoid granulations
Identify on a bony skull where the dural folds attach.
Falx cerebri: crista galli anteriorly
Tentorium cerebelli: dorsum sellae of sphenoid bone anteriorly
