The Role of Functional Dopamine-Transporter SPECT Imaging in Parkinsonian Syndromes, Part 2

Abstract

SUMMARY:The functional imaging technique most widely used in European clinics to differentiate a true parkinsonian syndrome from vascular parkinsonism, drug-induced changes, or essential tremor is dopamine-transporter SPECT. This technique commonly reports dopamine-transporter function, with decreasing striatal uptake demonstrating increasingly severe disease. The strength of dopaminetransporter SPECT is that nigrostriatal degeneration is observed in both clinically inconclusive parkinsonism and early, even premotor, disease. In this clinical review (Part 2), we present the dopamine-transporter SPECT findings in a variety of neurodegenerative diseases, including multiple system atrophy, progressive supranuclear palsy, corticobasal degeneration, and dementia with Lewy bodies. The findings in vascular parkinsonism, drug-induced parkinsonism, and essential tremor are also described. It is hoped that this technique will be the forerunner of a range of routinely used, process-specific ligands that can identify early degenerative disease and subsequently guide disease-modifying interventions.

Imaging analysis of Parkinson’s disease patients using SPECT and tractography

“…Single-photon emission tomography (SPECT) is commonly used for PD diagnosis7. SPECT imaging using 123 I-Ioflupane ( 123 I-Ioflupane-SPECT) provides information based on local binding of presynaptic dopamine transporters (DaTs) with 123 I-Ioflupane, which has been shown to be highly correlated with PD progression78.…”

“…SPECT imaging using 123 I-Ioflupane ( 123 I-Ioflupane-SPECT) provides information based on local binding of presynaptic dopamine transporters (DaTs) with 123 I-Ioflupane, which has been shown to be highly correlated with PD progression78. This binding measure is quantitative and assesses the spatial distribution of dopamine transporters.…”

Neuromagnetic investigations of mechanisms and effects of STN-DBS and medication in Parkinson's disease

“…DaT is confined to the presynaptic nerve endings and generally lead to a maximal signal in the putamen and caudate where they innervate striatal GABAergic projection neurons expressing either D1 or D2 receptors. The degeneration of nigrostriatal innervations leads to a decreased signal in PD patients compared to patients with other disorders like essential tremor (ET) Booth et al, 2015).…”

“…PD, as we know now, is principally caused by the degeneration of dopaminergic neurons in substantia nigra pars compacta which are situated in the mid brain along with the loss of dopamine transporters (DaT) located on dopaminergic terminals in striatum, that play a major role in transporting excess dopamine back into the presynaptic neuron (Jankovic, 2008;Booth et al, 2015). Clinical diagnosis is largely based on manifestation of bradykinesia with either rigidity or tremor or both (Postuma et al, 2015).…”

“…2.2). (Booth et al, 2015) and compared to an ET patient (bottom) 2.2 Basal ganglia-cortical motor loop and PD…”