3. Parkinson's Disease

• Parkinson's Disease is a neurodegenerative disorder that affects predominantly dopamine producing (dopaminergic) neurons in a specific area of the brain called substantia nigra.
• Parkinson's Disease develops slowly over the years.
• The symptoms of Parkinson's Disease are different from one person to another.
• The pathophysiology of Parkinson's Disease involves a gradual loss of cells in the substantia nigra.
• Dopamine connects the substantia nigra and the corpus striatum to regulate muscle activity.
• Levodopa is the Gold Standard in PD therapy, combined with Carbidopa (prevents levodopa from being metabolized into the gastrointestinal tract), reducing slowness, stiffness and tremor.
• The Unified Parkinson's Disease Rating Scale (UDDRS) is a more comprehensive tool used to account for non motor functioning.
• Changes in posture, walking, and facial expression occur in stage 2 of PD.
• Selegiline slows down the activity of the enzyme MA0-B, the enzyme that metabolizes dopamine in the brain, delaying breakdown of levodopa-induced and naturally occurring dopamine.
• PD stages 1 and 2 are characterized by mild symptoms that don't interfere with activities of daily living, including tremor, which occurs on one side of the body only.
• Stage 3 of PD, also known as mid stage, is characterized by loss of balance and slowness, with falls common.
• COMT Inhibitors, such as Entacapone and Tolcapone, treat fluctuations in response to levodopa by inhibiting the Catechol-0-Methyltransferase enzyme, which metabolizes levodopa in the bloodstream.
• Patients in stage 4 of PD may require a walker for movement and are unable to live alone.
• Dopamine agonists, such as Bromocriptine, Pergolide, Pramipexole, and Ropinirole, mimic the role of chemical messengers and can be prescribed alone or with levodopa.
• Hoehn and Yahn stages are a rating scale that describes motor symptoms progress in PD.
• Stage 5 of PD is characterized by stiffness in the legs that makes it impossible to stand or walk, requiring a wheelchair or bedridden status.
• Anticholinergic Medications, such as Amantadine, can be used in PD.
• Parkinsonism is the clinical syndrome that results from degeneration of dopaminergic neurons
• Cramping (dystonia): Sustained/repetitive twisting or tightening of muscle.
• Drooling (sialorrhea)
• Dyskinesia: Involuntary erratic, writhing movements of the face, arms, legs, or trunk.
• Festination: Short, rapid steps during walking; often seen in association with freezing.
• Freezing: appearance of being stuck in place.
• Masked face (hypomimia): Results from the combination of Bradykinesia and rigidity.
• Micrographia: small, untidy, and crumpled handwriting due to Bradykinesia.
• Soft speech (hypophonia): Soft, sometimes horse, that can occur in PD.
• Low dopamine levels, low norepinephrine levels, Lewy Bodies, autoimmune factors, and genetic factors are causes and risk factors of Parkinson's Disease.
• Early Warning Signs of Parkinson's Disease

  
• Bradykinesia + Tremor or Rigidity = Parkinson's Disease.
• Amantadine is an antiviral medication that reduce symptoms of PD.
• Dopamine agonists mimics the role of chemical messengers in the brain.
• COMT Inhibitors like, entacapone and tolcapone, treat flunctuations in response to levodopa.
• Anticholinergic Medications blocks acetylcholine (a chemical in the brain) whose effects become more pronounced when dopamine levels drop.
• Surgeries to treat Parkinson's Disease:

  • Stereotactic surgery
  • Pallidotomy
  • Thalamotomy
  • Deep Brain Stimulation (DBS)
• Deep Brain Stimulation (DBS): Electrodes are implanted into specific areas of the brain to stimulate nerve cells and improve motor function.
• Pallidotomy: A surgical procedure where part of the globus pallidus is destroyed to relieve tremors.
• Thalamotomy: A surgical procedure where part of the thalamus is destroyed to relieve tremors.