Parkinson's disease: Diagnosis and therapy

• Publisher: John Wiley and Sons
• Year: 1992
• Tongue: English
• Weight: 467 KB
• Volume: 7
• Category: Article
• ISSN: 0885-3185
• DOI: 10.1002/mds.870070565

✦ Synopsis

p.:. ,ilkinson's disease (PD) is associated with Lewy body degeneration of the substantia nigra, ventrolateral dopaminergic projections to the lptitaiiien being particulalry targeted. In other tlcgenei-~tive disorders causing parkinsonism, viicli as striatonigral degeneration (SND), progressive supranuclear palsy (PSP), and coi-ticobasal degeneration (CBD), the nigral dopaminergic projections to the caudate are sifnificantly more involved. By measuring striatal IWdopa uptake with positron emission toniogiaphy (PET) atypical parkinsonian syndromes can be distinguished from PD by their relatively greater loss of caudate signal. Sti-iatal D2 receptor levels are normal or raised in untreated PD, while these receptors degeiielate it1 SND and PSP. Non-demented PD Ixilients have normal striatal and frontal mettiholism, while this is reduced in SND and PSP. CBD patients show a characteristic asymmetrical focal loss of inferior parietal and tlialaniic metabolism. Atypical parkinsonian syndromes can, therefore, be also distinguished fiom Parkinson's disease by using PET to meiisure striatal D2 receptor density, and striatal iind cor~ical metabolism. On average PD patients show a 50% loss of put;imen IWdopa uptake, with at least a 35% loss at the onset of symptoms. PET can detect sub-clinical n i g a l pathology in at-risk relatives of patients with familial parkinsonism and in sub.iects exposed to toxins such as MPTP. PET can also show evidence of underlying PD in patients with isolated tremor, and i n patients with sever-e rigidity taking conventional doses of iieiiroleprics. Wirh the advent of neuroprotective agents for PD PET can help identify subjects with early disease who could potentially benefit from these compounds.