.CEREBELLAR DISEASES- CLINICAL ASPECTS
(By Dr.S.UMA DEVI.MD)
Diagnosis:
Most important and diagnostic physical signs are:
I.Ataxia- ( meaning poor coordination of movements)
-gait ataxia
-Truncal ataxia
-Limb ataxia
- Ocular ataxia-Nystagmus (not an essential feature of cerebellar
disease)
II. Rapid alternative movements affected.-Disdiadokokinesia
III. Dys arthria
IV. Hypotonia
Points to note: -
Signs and symptoms of cerebellar disease depends on if it is-
✱1.Acute or chronic
✱2.Midline lesion (Vermis) or hemispherical lesion
✱3.Unilateral or bilateral
and
4.✱Involvementof cerebellar connection in brain stem.
The effects are best seen in acute lesion rather than in chronic lesion.
-because in chronic disease compensation occurs and signs are less marked.
In vermis affection mainly equilibrium is affected.
In an unilateral lesion, signs are made out on the same side of the lesion
because cerebellar fibres cross the midline twice.
Role of cerebellum in genesis of voluntary movements
As a first step the idea of performing the movement takes place in association
area of cortex
2. Then appropriate cells are stimulated in the cortex
3. Impulses then travel via pyramidal tract to anterior horn cells and
movement is performed.
4. Smooth and coordinated nature of these movements is brought on by
cerebellum.
When cerebellum is affected,
Muscle tone and movements are affected.
Hypotonia:
It is an important sign of cerebellar disease.
Hypotonia is more obvious in acute lesion than in chronic.
It is due to loss of control held by cerebellum normally upon the stretch
reflex.
Hypotonia is made out by
1. Passive movements of the limbs.
2. . By tapping an outstretched arm upon which the arm shows greater
displacement than normal. This is due to failure of hypotonic muscle to fix
the arm at the shoulder.
3.When the affected limb is shaken, the hand flaps. This flapping movement
makes a wider excursion on abnormal side.
4.The stretch reflexes are either diminished or pendular.
5.When a knee jerk is elicited, a series of (more than 3) diminishing
oscillations are made.
Alteration of Movements in cerebellar diseases.
Direction
Distance
Synergy
Force and rate of contraction in the movement are affected,
manifesting with the following signs
CEREBELLAR SIGNS:
1.Dyssynergia
2. Dysmetria
3.Dis diadokokinesia
4. Intension tremor
5. Incoordination or inaccurate movements
Gait ataxia
Truncal ataxia
Dysarthria
6.Nystagmus.
1. DYS SYNERGIA:
-Failure of synergy
-Failure of harmonious action of synergistic muscles.
Leads to fragmentation
i.e. Movement is broken down into component parts sequentially.
2.DYSMETRIA
Distance of movement altered.
Hypermetria: Excessive range of movements
Hypometria: Dificient range of movement.
Occurs due to inability to determine the strength and duration of muscular
contraction in accomplishing a movement.
PAST POINTING:
With eyes closed if the patient is asked to move his limb and bring it back to its
original position especially in vertical plane,finger overshoots
-towards the side of cerebellar lesion. There is disturbance in range of
movement.
3.DISDIADOKOKINESIA:
➤Force and rate of contraction impaired
➤So rapidly alternating movements are performed clumsily.
➤ There is no coordination of agonists and antagonists.
➤Agonist do not stop acting at the precise moment and antagonists do not
start acting at the precise moment.
So rapid alternating movements become clumpsy.
4. INTENSION TREMORS:
❋ Comprises of Dys synergia plus dysmetria;
❋It is a form of action tremor,
-consisting of side-to-side oscillations as the finger reaches the target.
i.e. as the finger approaches the target it either overshoots or
-under shoots the target.
❋Then a series of corrective movements take place.
❋This side to side movements assumes rhythmical quality and
is called intension tremor.
❋Principally proximal muscles are involved,
-but tremor is transmitted distally, mechanically.
5.ATAXIA:
In coordinated or inaccurate movements.
5A. Gait ataxia:
❖Patient cannot walk on straight line.
Patient tilts to or staggers or falls on the side of the lesion.
❖Or reels from side to side.
❖Patient is frightened to stand – He spreads his feet apart
and holds on to support.
Gait ataxia in mildest form is demonstrated by making the patient to walk on
a line heel to toe. i.e. tandem walking.
The defect in gait lies in failure of coordination of proprioceptive, labyrinthine
and visual information.
So the reflex movements specially the ones that are required to make quick
adjustments while walking on irregular ground are affected.
5B. Truncal Ataxia;
❤Inability sit or stand without support.
❤ Tendency to fall backwards.
❤ Occurs in midline lesion.
❤This may be the only sign at times,
when only mid line structure is involved.
Disturbance of posture and stance:
In unilateral cerebellar lesions the head is tilted to the side of the lesion,
The shoulder droops and to accommodate this spine adopts a scoliotic posture
with concavity towards the affected side.
6.Speech:
Dysarthria:
✤Auto regulation of breathing is affected,
✤Coordination of speech and breathing is impaired.
✤Hence spluttering or Staccato speech.
-Certain words or syllables are ejaculated explosively.
✤Scanning speech is most typical of combined cerebellar and pyramidal lesion.
e.g. Multiple sclerosis.
Scanning Speech is slow,
Syllables are separated.
Enunciation imprecise,
Irregular
7. Hypotonia:
8.Nystagmus (Impaired ocular tone in extrinsic ocular muscles.)
Etiology of Cerebellar dysfunction:
I. Developmental cause (congenital)
Dandy walker’s malformation
Arnold chiari malformation
Von hippel lindu disease
Cranio vertebral anomaly.
Cerebellar agenesis. (Rare)
II,.Demyelinating :
Multiple sclerosis
III.Degenerative
Ataxia telengectasia
Friedrick’s ataxia
IV Drugs /toxins:
Phenytoin
Alcohol.
Carbon monoxide.
V.Neoplastic :
Medullo blastoma,(common in children)
Hemangio blastoma
Astrocytoma-
Metastasis from lung and breast
Paraneoplastic.
Non-neoplastic space occupying lesion:
Abscess
Hydatid cyst
VI Infective:
Acute cerebellitis
Acute disseminated encephalomyelitis
Abscess formation
Gullian- Barre Variation
VII.Metabolic:
Myxedema
Paraneoplastic syndrome.
Alcohol
VitB1 deficiency.
Inborn errors of metabolism
VIII.Vascular:
Cerebellar hemorrhage; cerebellum is especially prone.
Cerebellar infarction
PICA Syndrome.(Posterior Inferior Cerebellar Artery Syndrome)
Atherosclerosis, angitis rarely
.
Common degenerative conditions with family history:
Progressive cerebellar degeneration:
Primary parenchymatous degeneration of cerebellum
Olivo rubro cerebellar atrophy
Olivo pontine cerebellar atrophy
Delayed cortico cerebellar atrophy
Spinocerebellar Degeneration:
1.Friedreich’s ataxia
2. Roussy- Levy Syndrome.
3. Bassin Kornwig ‘s syndrome.
4. Hereditary spastic paraplegia.
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(By Dr.S.UMA DEVI.MD)
Diagnosis:
Most important and diagnostic physical signs are:
I.Ataxia- ( meaning poor coordination of movements)
-gait ataxia
-Truncal ataxia
-Limb ataxia
- Ocular ataxia-Nystagmus (not an essential feature of cerebellar
disease)
II. Rapid alternative movements affected.-Disdiadokokinesia
III. Dys arthria
IV. Hypotonia
Points to note: -
Signs and symptoms of cerebellar disease depends on if it is-
✱1.Acute or chronic
✱2.Midline lesion (Vermis) or hemispherical lesion
✱3.Unilateral or bilateral
and
4.✱Involvementof cerebellar connection in brain stem.
The effects are best seen in acute lesion rather than in chronic lesion.
-because in chronic disease compensation occurs and signs are less marked.
In vermis affection mainly equilibrium is affected.
In an unilateral lesion, signs are made out on the same side of the lesion
because cerebellar fibres cross the midline twice.
Role of cerebellum in genesis of voluntary movements
As a first step the idea of performing the movement takes place in association
area of cortex
2. Then appropriate cells are stimulated in the cortex
3. Impulses then travel via pyramidal tract to anterior horn cells and
movement is performed.
4. Smooth and coordinated nature of these movements is brought on by
cerebellum.
When cerebellum is affected,
Muscle tone and movements are affected.
Hypotonia:
It is an important sign of cerebellar disease.
Hypotonia is more obvious in acute lesion than in chronic.
It is due to loss of control held by cerebellum normally upon the stretch
reflex.
Hypotonia is made out by
1. Passive movements of the limbs.
2. . By tapping an outstretched arm upon which the arm shows greater
displacement than normal. This is due to failure of hypotonic muscle to fix
the arm at the shoulder.
3.When the affected limb is shaken, the hand flaps. This flapping movement
makes a wider excursion on abnormal side.
4.The stretch reflexes are either diminished or pendular.
5.When a knee jerk is elicited, a series of (more than 3) diminishing
oscillations are made.
Alteration of Movements in cerebellar diseases.
Direction
Distance
Synergy
Force and rate of contraction in the movement are affected,
manifesting with the following signs
CEREBELLAR SIGNS:
1.Dyssynergia
2. Dysmetria
3.Dis diadokokinesia
4. Intension tremor
5. Incoordination or inaccurate movements
Gait ataxia
Truncal ataxia
Dysarthria
6.Nystagmus.
1. DYS SYNERGIA:
-Failure of synergy
-Failure of harmonious action of synergistic muscles.
Leads to fragmentation
i.e. Movement is broken down into component parts sequentially.
2.DYSMETRIA
Distance of movement altered.
Hypermetria: Excessive range of movements
Hypometria: Dificient range of movement.
Occurs due to inability to determine the strength and duration of muscular
contraction in accomplishing a movement.
PAST POINTING:
With eyes closed if the patient is asked to move his limb and bring it back to its
original position especially in vertical plane,finger overshoots
-towards the side of cerebellar lesion. There is disturbance in range of
movement.
3.DISDIADOKOKINESIA:
➤Force and rate of contraction impaired
➤So rapidly alternating movements are performed clumsily.
➤ There is no coordination of agonists and antagonists.
➤Agonist do not stop acting at the precise moment and antagonists do not
start acting at the precise moment.
So rapid alternating movements become clumpsy.
4. INTENSION TREMORS:
❋ Comprises of Dys synergia plus dysmetria;
❋It is a form of action tremor,
-consisting of side-to-side oscillations as the finger reaches the target.
i.e. as the finger approaches the target it either overshoots or
-under shoots the target.
❋Then a series of corrective movements take place.
❋This side to side movements assumes rhythmical quality and
is called intension tremor.
❋Principally proximal muscles are involved,
-but tremor is transmitted distally, mechanically.
5.ATAXIA:
In coordinated or inaccurate movements.
5A. Gait ataxia:
❖Patient cannot walk on straight line.
Patient tilts to or staggers or falls on the side of the lesion.
❖Or reels from side to side.
❖Patient is frightened to stand – He spreads his feet apart
and holds on to support.
Gait ataxia in mildest form is demonstrated by making the patient to walk on
a line heel to toe. i.e. tandem walking.
The defect in gait lies in failure of coordination of proprioceptive, labyrinthine
and visual information.
So the reflex movements specially the ones that are required to make quick
adjustments while walking on irregular ground are affected.
5B. Truncal Ataxia;
❤Inability sit or stand without support.
❤ Tendency to fall backwards.
❤ Occurs in midline lesion.
❤This may be the only sign at times,
when only mid line structure is involved.
Disturbance of posture and stance:
In unilateral cerebellar lesions the head is tilted to the side of the lesion,
The shoulder droops and to accommodate this spine adopts a scoliotic posture
with concavity towards the affected side.
6.Speech:
Dysarthria:
✤Auto regulation of breathing is affected,
✤Coordination of speech and breathing is impaired.
✤Hence spluttering or Staccato speech.
-Certain words or syllables are ejaculated explosively.
✤Scanning speech is most typical of combined cerebellar and pyramidal lesion.
e.g. Multiple sclerosis.
Scanning Speech is slow,
Syllables are separated.
Enunciation imprecise,
Irregular
7. Hypotonia:
8.Nystagmus (Impaired ocular tone in extrinsic ocular muscles.)
Etiology of Cerebellar dysfunction:
I. Developmental cause (congenital)
Dandy walker’s malformation
Arnold chiari malformation
Von hippel lindu disease
Cranio vertebral anomaly.
Cerebellar agenesis. (Rare)
II,.Demyelinating :
Multiple sclerosis
III.Degenerative
Ataxia telengectasia
Friedrick’s ataxia
IV Drugs /toxins:
Phenytoin
Alcohol.
Carbon monoxide.
V.Neoplastic :
Medullo blastoma,(common in children)
Hemangio blastoma
Astrocytoma-
Metastasis from lung and breast
Paraneoplastic.
Non-neoplastic space occupying lesion:
Abscess
Hydatid cyst
VI Infective:
Acute cerebellitis
Acute disseminated encephalomyelitis
Abscess formation
Gullian- Barre Variation
VII.Metabolic:
Myxedema
Paraneoplastic syndrome.
Alcohol
VitB1 deficiency.
Inborn errors of metabolism
VIII.Vascular:
Cerebellar hemorrhage; cerebellum is especially prone.
Cerebellar infarction
PICA Syndrome.(Posterior Inferior Cerebellar Artery Syndrome)
Atherosclerosis, angitis rarely
.
Common degenerative conditions with family history:
Progressive cerebellar degeneration:
Primary parenchymatous degeneration of cerebellum
Olivo rubro cerebellar atrophy
Olivo pontine cerebellar atrophy
Delayed cortico cerebellar atrophy
Spinocerebellar Degeneration:
1.Friedreich’s ataxia
2. Roussy- Levy Syndrome.
3. Bassin Kornwig ‘s syndrome.
4. Hereditary spastic paraplegia.
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