Neuroanatomy and imaging Flashcards
What are nerve fibers in the CNS called?
Tract
What are nerve fibers/axons in PNS called?
Nerve
What does diencephalon include?
Thalamus
Hypothalamus
Third ventricle
Interventricular foramen
Cerebral aqueduct
Fourth ventricle
Median apertur
What are the 3 primary vesicles in the brain?
Forebrain (Prosencephalon), MIdbrain (Mesencephalon) and hindbrain (Rhombencephalon)
What are the secondary vesicles?
Forebrain –> Telencephalon, diencephalon
Midbrain –> Mesencephalon
Hindbrain –> Metencephalon, myelencephalon
What are the derivatives of the telencephalon?
Cerebral hemisphere
What is the cavity found in the cerebral hemispheres?
Lateral ventricles
What is the derivative of the diencephalon?
Thalamus, hypothalamus, epithalamus, subthalamus
What is the cavity found in the Thalamus, hypothalamus, epithalamus, subthalamus?
third ventricle
What is the derivative of the mesencephalon?
Midbrain
What is the cavity found in the midbrain?
Cerebral aqueduct
What is the cavity found in the pons and medulla oblongata ?
Pons, medulla oblongata
What is the derivative of the metencephalon?
Pons
What is the derivative of the myelencephaon?
Medulla oblongata
What makes the CSF?
Choroid plexuses, largely in the lateral ventricles
What happens if the cerebral aqueduct is blocked?
Hydrocephalus
Which ventricles would swell if the aqueduct were blocked?
Third and lateral ventricle
What are some landmarks seen?
Cerebellar peduncles on axial and saggital view are on each side of midline they connect the cerebellum with other parts of the brainstem
What is the finction of the ligamentum denticulatum?
Preventing displacement of spinal cord within vertebral column
What does the anterior root of the spinal cord contain?
Motor fibers from the anterior horns and autonomic fibers from the lateral horns
What is found in the posterior root?
Purely sensory carries post. roo ganglion (spinal ganglion)
What does the posterior ramus supply?
Muscles and skin of the back
Why do babies show positive babinski sign?
The corticospinal tract are not myelinated
What is lamina II of the spinal cord?
Substantia gelatinosa In dorsal horn
What are the neurons of lamina IX?
motor neurons in ventral horn
Where are preganglionic sympathetic neurons found?
Laeral horn only in the thoracic cord part of lamina VII
What does injury to the lower motor neuron lesion cause?
Nerve injury; poliomyelitis: flaccid paralysis, rapid muscle wasting, fibrillation and fasiculation
What does upper motor neuron lesions cause?
Spinal injury –> spastic paralysis, little muscle wasting, babinsky sign
What do degenerated corticospinal tracts get replaced by?
Astrocytes (glial cells)
What happens if a branch of the basilar artery supplying the corticospinal tract is blocked?
Locked in syndrome
Where does the brain form from?
The rostral end of the neural tube
What forms the brain vesicles in embryology?
The cavity of the tube
What forms the spinal cord in the neural tube?
The caudal part
When do the anterior and posterior neuropores close?
Anterior on 25th day and posterior on 27th day
What is the brainstem formed of?
Midbrain, pons and medulla oblongata
Where does the 4th ventricle lie?
In between PONS and MO infront and cerebellum behind
What is the extent of the medulla oblongata?
From the lower border of the foramen magnum below to the lower border of the pons above
What are the parts of the medulla ?
Closed medulla: Is the lower part and encloses the central canal
OPen medulla : is the upper part and opens into the 4th ventricle and forms the lower part of its floor
What are the 3 elevations of the medulla found on the antereo lateal surface?
1.Pyramid : formed by pyramidal tract
2.Olive: formed by the inferior olivary nucleus
3.Inferior cerebellar peduncle (ICP): Lies postereo-lateral to olive. It communicates between: cerebellum and medulla
Where does the antereolateral sulcus lie?
Between pyramid and olive
Which nerve exits from the antereo-lateral sulcus?
Hypoglossal nerve
Where does the postero-lateral sulcus lie?
Between olive and inferior cerebellar peduncle
Which nerves exit through the postero-lateral sulcus?
9th and 10th cranial accessory (11th)
What are the posterior median sulcus found on closed medulla ?
- Gracile tract: medial & ends in gracile tubercle (nucleus)
2.Cuneate tract: in the middle & ends in cuneate tubercle (nucleus)
3.Inferior Cerebellar peduncle (ICP)
What forms the base (above) in the open medulla?
Formed by medullary stria
