Transcript Clinical Case

Clinical Case
A patient delays initiation of movement,
displays an uneven trajectory in moving her
hand from above her head to touch her nose,
and is uneven in her attempts to demonstrate
rapid alternation of pronating and supernating
movements of the hand and forearm. Which
regions of the brain is most likely contains the
lesion?
Clinical Case
A 55-year-old male had been complaining about his having
difficulty in coordinating the use of his arms in meaningful
ways. For example, when examined by a neurologist, the
patient was unable to move his finger accurately to his nose
from his side when requested to do so but instead he would
undershoot or overshoot the target. He also had difficulty in
making Rapid alternating rotational movements of the hand.
The neurologist believed that the patient was suffering from a
disorder that resulted in a lesion of a region of the cerebellum
or structures related to it. Which regions of the cerebellum is
most likely contained this lesion
Cerebellum External features
1. located in posterior cranial fossa.
2. Communicate with brain stem by cerebellar
peduncles.
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Superior cerebellar peduncles( Brachium
conjunctiva)
Middle cerebellar peduncles (Brachium pontis)
Inferior cerebellar peduncle (Restiform Body
Crebellum External features cont..
Cerebellum Classification
Classification
Archicerebellum
Paleocerebllum
Neocerebellum
(Equilibrium, Tone & Posture of trunk Muscles)
(Tone & Posture of limb Muscles)
(Smooth performance of skilled act by coordination of move)
Classification by its Connections
Vestibulocerebellum
Spinocerebellum
cerebrocerebellum
Crebellum External features cont..
Subdivision of Flocculonodular Lobe
Nodulus
Flocculus
Subdivision of Anterior Lobe
Vermis
Lingula
Central Lobule
Hemisphere
Ala Central Lobule
postcentral fissure
Culmen
Quadrangular Lobule
Crebellum External features cont..
Subdivision of Posterior Lobe
Vermis
crebellar Hemisphere
Declive
Simple Lobule
postcentral fissure
Folium
Superior Semilunar Lobule
horizontal fissure
Inferior Semilunar Lobule
Tuber
Gracile Lobule
prepyramidal fissure
Pyramid
Biventer Lobule
secondary fissure
Uvula
Tonsil
Crebellum Internal features cont..
Cerebellar Cortex
Molecular Layer
Purkinje Cell Layer
Granular Layer
Deep Cerebellar Nuclei
Fastigial Nuclei
(Nucleus Interpositus)
Emboliform Nucleus
Globose Nucleus
Dentate Nucleus
Crebellum Internal features cont..
Cerebellar Cortex
I. Molecular Layer
Stellate Cell (inhibitory)
afferent: parallel fiber
efferent: Purkinje cell dendrite
Basket Cell ---- GABA (inhibitory)
afferent: parallel fiber
efferent: Purkinje cell soma
Parallel Fiber
granule cell axon
Purkinje Cell Dendrite
Cerebellum Internal features cont..
II. Purkinje Cell Layer
Purkinje Cell
-- 15,000,000 in number
-- GABA (inhibitory)
afferent: parallel fiber
climbing fiber
stellate cell
basket cell
efferent: deep cerebellar nuclei nuclei
Cerebellum Internal features cont..
III. Granular Layer
Granular Cell
-- 50,000,000,000 in number
-- glutamic acid (excitatory)
afferent: mossy fiber
efferent: Purkinje cell dendrite
basket cell, stellate cell
Golgi cell
Golgi Cell
-- GABA (inhibitory)
afferent: parallel fiber, mossy fiber rosette
efferent: granule cell dendrite
Cerebellum Internal features cont..
Synaptic Glomerulus
Afferent terminals on granular layer
 Mossy Fiber Rosette
-- afferent fibers except
inferior olivary input
-- 2/3 of medullary center
 Granular Cell Dendrite
-- main afferent input
 Golgi Cell Axon
-- synapse on granule cell dendrite
-- GABA (inhibitory)
- Surrounded by Astrocyte Foot Process
Cerebellum
Connections
1. Inferior Cerebellar Peduncle
Restiform Body
Posterior Spinocerebellar Tract
Olivocerebellar tract
Cuneocerebellar Tract
Reticulocerebellar Tract
Juxtarestiform Body
Vestibulocerebellar Tract
Primary Vestyibular Fiber
Cerebellum
Afferent Connections (2):
2. Middle Cerebellar Peduncle
Pontocerebellar fiber
Corticopontocerebellar Fiber
Reticulocerebellar Fiber
3. Superior Cerebellar Peduncle
Anterior Spinocerebellar Tract
Cerulocerebellar fiber
Raphecerebellar fiber
Rubrocerebellar fiber
Hypothalamocerebellar fiber
Connections
Cerebellum
Connections
Efferent Connections:
1. Superior Cerebellar Peduncle
Cerebellothalamic fiber
- From 3 deep nuclei to VPLo, VLc, CL
Cerebellorubral fiber
- From nucleus globusus
And dentate nucleus
2. Inferior Cerebellar Peduncle
Fastigiovestibular fiber
Descending portion of
Uncinate fasciculus
Cerebellar Pathway
Main Connections of the Vestibulocerebellum
Vestibular
Organ
Floculonodular
Lobe
VESTIBULAR NUCLEUS
Vermis
vestibulospinal tract
MLF
lower motor neuron
LMN
FASTIGIAL
NUCLEUS
ARCHICEREBELLUM
Main Connections of the Paleocerebellum
RED
NUCLEUS
rubrospinal
tract
NUCLEUS
INTERPOSITUS
Inferior
Olivry
Nucleus
lower motor neuron
SPINAL CORD
ANTERIOR
LOBE
PARAVERMAL
ZONE
PALEOCEREBELLUM
spinocerebellar tract
Main Connections of the Neocerebellum
CEREBRAL
CORTEX
pyramidal
tract
lower motor neuron
LMN
THALAMUS
Pontine
Nucleus
DENTATE
NUCLEUS
POSTERIOR
LOBE
CEREBELLAR
HEMISPHERE
NEOCEREBELLUM
Pyramidal Tract and Associated Circuits
upper motor neuron
UMN
BASAL
GANGLIA
Cerebellum
pyramidal
tract
lower motor neuron
UMN
Cerebellum and Automatic Motor Control
Motor Cortex
CEREBELLUM
Red Nucleus
Reticular
Formation
Lower Motor Neuron (LMN)
Vestibular
Nucleus
Proprioceptors
Functions Of Cerebellum
 Maintenance of Equilibrium
- balance, posture, eye movement
 Coordination of automatic movement of
walking and posture maintenance
- posture, gait
 Adjustment of Muscle Tone
 Motor Leaning – Motor Skills
 Cognitive Function
Cerebellum
Disorders
• Ataxia: incoordination of movement
- decomposition of movement
- dysmetria, past-pointing
- dysdiadochokinesia(Adidydakokinesia)
- rebound phenomenon of Holmes
- gait ataxia, truncal ataxia, titubation
• Intention Tremor
• Hypotonia, Nystagmus
Cerebellum
Disorders
• Archicerebellar Lesion: medulloblastoma
• Paleocerebellar Lesion: gait disturbance
• Neocerebellar Lesion: hypotonia, ataxia,
tremor