BASAL GANGLIA & PARKINSONISM Flashcards
Basal Ganglia is a MISNOMER
Basal Nuclei
Structural & Functional Components of BASAL GANGLIA
Parts of Substantia Nigra
- Pars Reticulata: Homologous to GP internus
- Pars Compacta
Wilson’s Pencil
Thin Myelinated (OR) Unmyelinated axons which are afferents & afferents passing through Straitum
⭐ Direct Pathway in Basal Ganglia does
⭐ Indirect Pathway in Basal Ganglia does
🧠⚡INdirect ⚡
⭐ Direct Pathway in Basal Ganglia does
🎯 Stimulates MOVEMENT
⭐ Indirect Pathway in Basal Ganglia does
🎯 INhibits MOVEMENT
Functions of BASAL GANGLIA
⭐ Inhibitory at REST ⭐
✨ TIMING & SCALING the intensity of movement
✨ Planning & Programming movement
✨ Cognitive component of Motor Activity
✨ Tone adjustment
✨ Movement Enhancer
2 EXTRA THINGS PRESENT in INDIRECT PATHWAY than DIRECT PATHWAY
- Globus pallidus Externus
- Subthalamus
Glutamate is EXCITATORY neurotransmitter, Released in BASAL GANGLIA by
- Cerebrum
- Subthalamus
- Thalamus
GABA is INHIBITORY neurotransmitter, Released in BASAL GANGLIA by
Corpus Straitum
✨ Caudate nucleus
✨ Putamen
✨ Globus pallidus
⭐ DOPAMINE is Released in BASAL GANGLIA
⭐ ACETYLCHOLINE is Released in BASAL GANGLIA
⭐ DOPAMINE is Released in BASAL GANGLIA
🎯 Substantia Nigra
⭐ ACETYLCHOLINE is Released in BASAL GANGLIA
🎯 Putamen
Direct pathway in BASAL GANGLIA
Indirect pathway in BASAL GANGLIA
Nigrostraital Pathway
Releases Dopamine
✨ D1 Receptor: Direct Pathway: Stimulate Movements
✨ D2 Receptor: Indirect Pathway: Inhibit Movements
Athetosis is DUE TO LESION in
Globus Pallidus
Athetosis
Slow
INVOLUNTARY
IRREGULAR
FORCEFUL
WRITHING movement
HANDS, ARM, NECK & FACE
Chorea is DUE TO LESION in
Caudate Nucleus
(OR)
Putamen
Chorea
Dancing like movement
Involuntary
Flicking movement
Hand, Face & Shouldera
Hemiballismus is DUE TO LESION in
Subthalamus
⬇️
Sudden Flailing movement of Entire limb
Parkinson’s disease is DUE TO LESION in
Substantia Nigra
Neurological Manifestation of WILSON DISEASE DUE TO
Copper Deposition in Lentiform nucleus
Only EXCITATORY NUCLEUS OF BASAL GANGLIA
Subthalamus
🚦DIFFERENTIAL DIAGNOSIS🚦 of HYPOKINETIC MOVEMENT
- Parkinson’s
- Non-Parkinson’s etiology
✨ Hypothyroidism
✨ Catatonia
⚡⚡ MOST COMMON NEURODEGENERATIVE DISEASE
⚡⚡ 2nd MOST COMMON NEURODEGENERATIVE DISEASE
⚡⚡ MOST COMMON SUBCORTICAL NEURODEGENERATIVE DISEASE
⚡⚡ MOST COMMON NEURODEGENERATIVE DISEASE
🎯 ALZHEIMER’S DISEASE
⚡⚡ 2nd MOST COMMON NEURODEGENERATIVE DISEASE
🎯 PARKINSON’S DISEASE
⚡⚡ MOST COMMON SUBCORTICAL NEURODEGENERATIVE DISEASE
🎯 PARKINSON’S DISEASE
Age of Parkinson’s presentation
≥ 65 yrs
If age of presentation of Parkinson’s DISEASE is ≤ 60yrs, known as
Familial Parkinson’s Disease
⚡⚡ MOST COMMON CAUSE of FAMILIAL PARKINSON’S
🧬 MODE OF INHERITENCE 💉
PARK8
⭐ AD
⭐ LRRK2 mutation
FAMILIAL Forms of PARKINSON’S
Function of Alpha Synuclein
Lipid Binding Protein ASSOCIATED with Synapses
Substantia Nigra is Pigmented DUE TO:
Presence of NEUROMELANIN Granules
⬇️
Synthesis of Dopamine
Lewy Body
Accumulation of Alpha Synuclein
Synuclein deposition occurs 1st in
Lower BRAINSTEM (MEDULLA)
⬇️
PONS
⬇️
MIDBRAIN
⬇️
SUBSTANTIA NIGRA
Prion like spread within Brain is ASSOCIATED with
PARKINSON’S DISEASE
✨ Alpha Synuclein aggregates can be released from 1 neuron & taken uup by another
Absent Swallow Tail Sign is seen in
MRI: PARKINSON’S DISEASE
MRI Signs of PARKINSON’S DISEASE
- Loss of Pigmentation in SUBSTANTIA NIGRA
- ABSENT SWALLOW TAIL SIGN
- B/L HYPERINTENSE GREY MATTER on upper Midbrain
Lewy Bodies can be seen in
- Other Pigmented nuclei in Brainstem
- Dorsal Nucleus of Vagus
- Nucleus BASALIS
- Other Cortical ASSOCIATION Areaa
Primary & Secondary PARKINSON’S Disease
🧠⚡2° causes: We Will Have DPT² ViaL⚡
- WILSON’s disease
- Whipple’s DISEASE
- Head Trauma: Dementia pugilistica
- Drug induced
- Post-encepahlitic
- Toxins: Manganese, MPTP, CO, Cyanide
- Tumour / Thyroid Function ⬇️ ⬇️
- Vascular
- Liver Failure
Symptoms of PARKINSON’S DISEASE
🧠⚡Be SMART⚡
ASYMMETRICAL
➕
1. Bending Forward (OR) Tilt
2. Shuffling Gait
3. Mask like facies
4. Akinesia / Bradykinesia
5. Rigidity
6. Tremors
Earliest Symptom of PARKINSON’S DISEASE
Tremor
⬇️
Akinesia
⬇️
Axial Skeleton: Gait & Posture
⬇️
Sleep, ANS, Sensory
⬇️
Cognitive Symptoms