| خلاصه مقاله | Most patients (about 80-85%) diagnosed with Parkinson's disease
have what is called primary parkinsonism or idiopathic Parkinson’s
disease (meaning that the disease has no known cause). This type
tends to respond well to drugs that work by increasing or substituting
dopamine molecules in the brain.
Secondary parkinsonism does not respond well to dopaminergic
medications such as levodopa and include drug-induced
parkinsonism, vascular parkinsonism, normal _ pressure
hydrocephalus (NSA), corticobasal degeneration (CBD), progressive
supranuclear palsy (PSP) and multiple system atrophy (MSA). In
most cases, the diagnosis of probable PD can be made on clinical
grounds, and no ancillary investigations are needed, However, in
early PD the full triad of clinical symptoms and signs (bradykinesia,
tremor at rest and rigidity) may not yet be manifested. The lesion in
PD has been localized to the dopaminergic cells of the pars compacta
of the substantia nigra and definitive diagnosis of idiopathic PD,
requires histologic demonstration of intraneuronal Lewy body
inclusions in this area.
Most suitable sequences for diagnosis this disease are T2*-GRE and
SWI and then T1W images and Loss of the normal swallow tail
appearance of susceptibility signal pattern in the substantia nigra on
axial imaging is perhaps the most promising diagnostic sign.
PSP is more common forms of secondary parkinsonism and Main
radiologic feature is midbrain atrophy. MSA is a rare neurological
disorder characterized by a combination of 1. parkinsonism, 2.
cerebellar and pyramidal signs, and 3. autonomic dysfunction. CBD
present with cognitive dysfunction, usually in combination with
Parkinson-like symptoms. |