Parkinsons Society Ottawa Serving Ontario

DEFINITION

Progressive Supranuclear Palsy (PSP)

This is a drug resistant parkinsonism. It is characterized by the inability to move the eyes in an up and down movement, neck dystonia (a peculiar posturing of the neck causing the head to be fixed skyward), dysphagia (difficulty swallowing) and dysarthria (difficulty speaking), and a tendency to suddenly lose balance. Early symptoms are often vague and include mild disequilibrium with slowing, easy fatigability, minor personality changes and subtle visual symptoms such as blurring or double vision. With disease progression, walking becomes slow and deliberate with broad-based steps and progressive loss of balance. The facial expression is fixed and associated with frowning, and rapid blinking can occur.

Cortico-basal-ganglionic Degeneration (CBD)

This is a rare drug resistant parkinsonism. It is characterized by the marked asymmetry of the Parkinsonian features until late in the disease. The patients will frequently have apraxia (inability to properly use a limb for complex tasks despite normal power and only mild incoordination), action myoclonus (i.e. jerky abnormal movements superimposed on normal movements), "alien limb phenomenon"(one limb seems to have a mind of its own, sometimes actively interfering with planned movements), and stimulus sensitive myoclonus (involuntary jerking in response to light touch).
Early on the condition may be misdiagnosed as Parkinson's disease. Marked often painful rigidity may occur late in this disorder. Tremor is not as common as in Parkinson's disease.

Multiple System Atrophy (MSA)

The Multi-System Atrophies are a group of progressive neurodegenerative disorders that early on can mimic, or be mistaken for, Parkinson's Disease. This diagnosis is often made only after patients fail to improve with medication or develop atypical features. In Parkinson's only one main group of nerve cells die at an abnormally fast rate. In Parkinson's Disease replacing dopamine in pill form results in improved mobility.
In the Multi-System Atrophies a variety of groups of nerve cells die off. The cells that dopamine stimulates are involved. In this situation the "motor is damaged and just putting more oil in doesn't usually help". Thus dopamine replacement doesn't resolve the many problems associated with these disorders account for approximately 20% of all cases of parkinsonism.

Dementia with Lewy Bodies (DLB)

Parkinsonism preceding dementia by an arbitrary interval of 1 year or more is termed PD-D, and dementia that precedes or accompanies the onset of parkinsonism is labeled DLB. Patients with DLB have an older age at onset and shorter disease duration than patients with typical PD. Resting tremor is less common (55% verses 85%).
Patients with DLB have deficits in memory, attention, language, executive functions, and visuospatial and visuoconstructional abilities. They typically fall in the mild range on the MMSE (22-26). Visual hallucinations are reported (usually well formed, often benign, but sometimes threatening) in 40% to 75% of patients with DLB. They are usually unprovoked but may be seen in the setting of antiparkinsonian medications.
Rapid eye movement sleep behavior disorder (RBD) is a sleep disturbance (acting out dreams) that has been associated with Lewy Body disorders (PD and DLB). Supranuclear gaze palsies, although uncommon, have been reported.